Construction Works for the Rehabilitation of Centralized Irrigation Systems Along Nistru River

BIDDING DOCUMENTS IFB #PP6/THVAP/W/CB/03

CONSTRUCTION WORKS FOR THE REHABILITATION OF CENTRALIZED IRRIGATION SYSTEMS ALONG NISTRU RIVER

Section IX TECHNICAL SPECIFICATIONS

LOT #1 – CIS ‘JORA DE JOS’ PARTICULAR TECHNICAL SPECIFICATIONS

______Rehabilitation Works on CISs along Nistru River IFB #PP6/THVAP/W/CB/03 Millennium Challenge Account – Moldova

PARTICULAR SPECIFICATION TABLE OF CONTENTS

______Section IX. Specifications – Lot #1 / CIS ‘Jora de Jos’ 2 Rehabilitation Works on CISs along Nistru River IFB #PP6/THVAP/W/CB/03 Millennium Challenge Account – Moldova

1. PARTICULAR TECHNICAL SPECIFICATIONS

The Particular Technical Specifications (PTS) cover only those items that are specific to a particular scheme and includes:  The scope of work  Site information  Pipe’s detailed specification  Mechanical and electrical works in terms of specific performance and duty characteristics of pumping plant, motors and switchgear

The Particular Specification should be read in conjunction with the General Specification, which includes specifications and standards applicable to all work, materials, plant and equipment which are common to all schemes.

2. SCOPE OF WORKS

1.1 INTRODUCTION

The objectives of the contract is the construction, testing, commissioning and subsequent training of operation and maintenance staff in respect of the Rehabilitation of the Centralized Irrigation System in Jora de Jos (1215 ha). The Contract includes the furnishing of all labour, plant, equipment and materials required to complete the entire works, pre-commissioning, commissioning, testing, reinstatement of the Sites, preparation of working, shop and as-built drawings, training of operation and maintenance staff and the rectification of defects during the maintenance period specified in the Contract.

1.2 LOCATION OF WORKS

Jora de Jos village is located some 80 km North-East of the capital, Chisinau close to the Nistru River in Orhei district. Access is via a reasonable but variable standard asphalt road network as far as the Orhei town, then via village Susleni following a gravel road up to Jora de Jos village. The irrigation scheme lies between Nistru River on east side and along both sides of the road Susleni – Jora de Jos. The access to pumping station SPP-1 and SPP-2 is possible via an unpaved road. The access to pumping station SP-1 and SP-2 is possible via a gravel-paved road starting from Susleni village or Jora de Jos village.

1.3 SHORT DESCRIPTION OF THE WORKS

The works comprise:  The rehabilitation of the river intake and pressure pumping stations SPP-1, located on the right bank of the Nistru River, including: o Replacing the intake works, including installation of new fish protection devices and ice protection measures;

o Refurbishing the existing buildings and strengthening the structures to meet prevailing earthquake legislation; o Supply and installation of new pumps, motors, associated pipe-work and electric switch gear; o Landscaping, installing the fence and install water removal on the land around pumping stations SPP-1; o Rehabilitate the access road to the pumping stations SPP-1 and SPP-2;  The construction of some 4.36 km of a new pipe network supplied by SPP-1, running in parallel with the existing system and comprising: o 80 m of steel pipeline of 400 mm diameter; o 873 m of HDPE pipeline of 315 mm diameter; o 3393 m of HDPE pipeline of 400 mm diameter; o all necessary fittings, including new irrigation hydrants.  The rehabilitation of the river intake and lifting pumping stations SPP-2, located on the right bank of the Nistru River, including: o replacing the intake works, including installation of new fish protection devices and ice protection measures; o refurbishing the existing buildings and strengthening the structures to meet prevailing earthquake legislation; o supply and installation of new pumps, motors, associated pipe-work and electric switch gear; o landscaping, installing the fence and install water removal on the land around pumping stations SPP-2;  The rehabilitation of some 1,63 km of existing main pipe between SPP-2 and SP-1 comprising: o 200 m of steel pipeline of 800 mm diameter which will not be replaced (near SPP-2); o 1,435 m of cast iron pipeline of 800 mm diameter which will not be replaced; o Install all necessary air release valves and dewatering manholes.  The rehabilitation of the pressure pumping stations SP-1, located on the right bank of the Nistru River on the gravel road between Jora de Jos and Viscauti villages, including: o refurbishing the compensation basin; o refurbishing the existing buildings and strengthening the structures to meet prevailing earthquake legislation; o supply and installation of new pumps, motors, associated pipe-work and electric switch gear; o landscaping, installing the fence and install water removal on the land around pumping stations SP-1;

 The construction of some 11, 73 km of a new pipe network running in parallel with the existing system and comprising: o 368 m of steel pipeline of 400 mm diameter; o 2516 m of HDPE pipeline of 400 mm diameter; o 3053 m of HDPE pipeline of 315 mm diameter; o 927 m of HDPE pipeline of 250 mm diameter; o 2981m of HDPE pipeline of 225 mm diameter; o 218 m of HDPE pipeline of 200 mm diameter; o 1667 m of HDPE pipeline of 160 mm diameter; o all necessary fittings, including new irrigation hydrants.  The construction of some 4, 1 km of a new rising main pipe between SP-1 and SP-2 comprising: o 4106 m of steel pipeline of 700 mm diameter; o all necessary fittings, including new irrigation hydrants.  The rehabilitation of the pressure pumping stations SP-2, located on the right bank of the Nistru River on the gravel road between Susleni and Jora de Jos villages, including: o refurbishing the compensation basin; o refurbishing the existing buildings and strengthening the structures to meet prevailing earthquake legislation; o supply and installation of new pumps, motors, associated pipe-work and electric switch gear; o landscaping, installing the fence and install water removal on the land around pumping stations SP-2;  The construction of some 28, 6 km of a new pipe network running in parallel with the existing system and comprising: o 2113 m of steel pipeline of 500 mm diameter; o 999 m of steel pipeline of 400 mm diameter; o 3071 m of HDPE pipelines of 400 mm diameter; o 8234 m of HDPE pipelines of 315 mm diameter; o 4344 m of HDPE pipelines of 250 mm diameter; o 9335 m of HDPE pipelines of 225 mm diameter; o 129 m of HDPE pipelines of 200 mm diameter; o 453 m of HDPE pipelines of 160 mm diameter; o all necessary fittings, including new irrigation hydrants.

1.4 SITE INFORMATION

2.1.1 Limits of the sites

For the purpose of carrying out the Works the Contractor shall limit his installations and operations to the defined working areas described on the Contract drawings. The Contractor shall be responsible for complying with all relevant bylaws of related Municipalities, Utilities and Authorities and obtaining all necessary permits and licenses.

2.1.2 Access to sites

The projects area is located on right bank of the Nistru River along both sides of the gravel road between Susleni and Jora de Jos. Access to the river intakes and pumping stations is via several non paved roads. Access to the pipelines is either via the working easement along the existing pipelines or via the farm tracks which intersect the area.

2.1.3 Topography

The Jora de Jos irrigation areas are mostly on large terraces, with slopes not exceeding 8%. The absolute elevations of the relief vary within 27.00 - 224.00 m Baltic System. There are no settlements inside the project area.

2.1.4 Geology

Under geomorphologic zoning, this territory is located on the Dniester River terrace plain and is confined to the Middle-Dniester sub-district being zone bordering with the Trans- Dniester swell-like upland. The Middle-Dniester sub-district is represented almost completely by the late Pliocene terraces of the Dniester River.

This region is featured by prevailing valley-terrace shapes of relief dissected by the Pleistocene-Holocene age and modern erosion processes into the series of smaller areas.

Peculiarity of the territory consists in the dense network of well-developed gully and ravine- gully systems featured by vast morphologic diversity. Ravine-gully watersheds will define strength features of terrain, while gully ones will form the slope of runoff. In geomorphologic aspect, the territory is referred to several geomorphologic elements: the Dniester River floodplain, adjacent slopes and watersheds (multiple terraces of the Dniester River). On individual areas, slopes are affected by erosion processes; ravine depth achieves 7-10 m. Right bank of the Dniester River is abrupt and bold (more than 5 meters in some sections). Within boundaries of the area, there are deposits of middle and upper Pliocene represented by sands with gravel lenses (rare by clays) at the bottom and conglomerates, pebble gravel, sands, loams and fossil soils at the top.

The information Document attached to the Tender Documents contains Surveys from a 2012 investigation in the project areas. The studies indicate that in general the ground water table stands at some 8-10 meters below ground level except in proximity to the main intake pumping station SPP-1 and SPP-2, where the level tends to equate to the prevailing river level. However, the Contractor is required to undertake his own investigations and to satisfy himself as the geological conditions in the project area in so far as these may affect the Works.

2.1.5 Seismic activity

The current and official documents concerning seismic design parameters of Moldova are included in the Decree #25 dated 23 December 2009 of the Ministry of Construction and Regional Development "Approval of the Seismic Regions in the Republic of Moldova at scale 1:400,000". The Seismic Regionalization Map shows that all the Jora de Jos project area is included in the “7-degree seismic zone”.

2.1.6 Temperature

The temperature regime is temperate continental climate, characterized by hot summers and cold winters. Tables 1.1and 1.2 shows the average monthly temperatures for the project area sites.

Table 1.1-Montly average air temperatures

Districts Jan Feb Ma Apr May Jun Jul Aug Sep Oct No Dec Year r v Orhei/Jora de jos -3,3 -2,0 2,7 9,8 16,0 19,4 21,4 20,8 16,0 10,1 4,0 -0,8 9,5

Table 1.2-Minimum air temperatures

Districts Jan Feb Mar Apr Ma Jun Jul Au Sep Oct Nov Dec Year y g Orhei/Jora de ------1,8 3,6 7,8 5,5 10,8 -31,5 jos 29,8 31,5 23,0 8,5 2,4 21,7 22,4

2.1.7 Rainfall

Average monthly rainfall for the project area sites are indicated in Table 1.3.

Table 1.3-Montly average rainfall

Districts Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year Orhei/Jora de jos 32 32 31 39 52 71 65 50 41 35 41 37 526

2.1.8 Definitions

The following terms shall have the meanings hereby assigned to them:— ‘Topsoil’ any surface material capable of supporting vegetation and suitable for use in soiling areas to be grassed or cultivated. ‘Rock’ naturally-occurring material which in the opinion of the Engineer would normally have to be loosened either by blasting or by the use of pneumatic tools (other than clay spades) or by other rock quarrying methods or, if excavated by hand, by the use of wedges and sledge hammers. An isolated solid boulder or detached piece of rock shall qualify as Rock only if it exceeds 0.2m³ in volume. ‘ Bulk excavation in open cut (excluding Trench Excavation) down Excavation’ to levels specified in the Drawings or otherwise as being the general levels after completion of excavation other than Incidental Excavation. ‘ Trench excavation, to levels and limits specified in the Drawings or Excavation’ otherwise, of trenches into which pipes and the like are to be laid. ‘ Incidental excavation (generally in small quantities) below or outside the Excavation’ limits of Bulk Excavation and Trench Excavation, but excluding Excess Excavation. ‘ Excess excavation outside the limits specified for Bulk, Trench or Excavation’ Incidental Excavation. “HDPE” High Density Polyethylene

2.1.9 SUBMISSIONS BY THE CONTRACTOR

Submissions which the Contractor is required to make in relation to earthworks include, where relevant, the following:—

Drawings and survey notes: — Contractor’s record drawings of the ground level survey prior to the start of any earthwork; — information obtained from trial holes ordered by the Engineer; — Contractor's record drawings of any other level surveys taken for the purposes of measurement of quantities of excavation or filling, such as Rock level surveys; (Survey record drawings as specified above shall be submitted within 7 days of the completion of the survey work recorded on them.) — survey notes on depths of Trench Excavation; — proposals to excavate with sloping faces without support. — general arrangements; — general assembly, detailed shop and erection drawings; — detailed manufacturing drawings.

Data: — calculations for connection details, where requested by the Engineer; — welding procedure sheets.

Certificates: — mill tests, factory tests; — laboratory tests; — field tests; — conformity certificates.

Details of proposed methods: — proposed methods of excavation, transport of materials, filling and compaction; — proposed method of asbestos-cement handling and disposal; — proposed source of free-draining fill and methods of selective excavation or processing; — program for quality control of earthworks and proposals for the use of off- Site laboratories.

Samples:

— materials proposed for filling and for geotextiles, where specified or where specifically required by the Engineer; — materials proposed for filling joints between concrete slabs, pipes and concrete walls, any other joints requested by the Engineer.

2. PIPELINE AND PIPEWORK

2.1 PIPE’S SUMMARY

The pipelines are briefly described and quantified in Table 3.1 below:

______Section IX. Specifications – Lot #1 / CIS ‘Jora de Jos’ 10 Rehabilitation Works on CISs along Nistru River IFB #PP6/THVAP/W/CB/03 Millennium Challenge Account – Moldova Table 3.1 Breakdown of pipelines length for each material, diameter and type BoQ items GROUP 1 -JORA DE JOS CIS: QUANTITY HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, HPDE100, ASSESSMENT ND140/ ND160/ ND160/ ND180/ ND180/ ND200/ ND225/ ND225/ ND225/ ND225/ ND280/ ND280/ ND280/ ND315/ ND315/ ND315/ ND355/ ND355/ ND400/ ND400/ ND400/ Steel NP10 NP8 NP10 NP6 NP10 NP10 NP6 NP8 NP10 NP6 NP6 NP8 NP10 NP6 NP8 NP10 NP6 NP10 NP6 NP8 NP10 PIPE Pipe Length 140 160 160 180 180 200 225 225 225 250 280 280 280 315 315 315 355 355 400 400 400 300 400 500 700 800 # [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] [m] Main pipes HT 23 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 23 0 0 0 HT-1 201 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 201 HT-2 4144 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4144 0 MT-1 1107 0 0 0 0 0 0 0 0 0 0 0 0 1078 0 0 0 0 0 0 0 0 27 0 2 0 0 MT-2 623 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 17 0 0 0 0 606 0 0 0 0 0 MT-3 1611 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1611 0 0 0 0 0 0 0 MT-4 131 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 131 0 0 0 0 0 MT-5 2069 0 0 0 0 0 0 0 0 0 2069 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Sub-tot. [m] 9909 0 0 0 0 0 0 0 0 0 2069 0 0 1078 0 0 17 0 0 1611 0 736 27 23 2 4144 201 Secondary pipes 1KP2 1430 0 0 0 0 0 0 0 966 0 0 0 0 0 0 0 0 0 0 0 464 0 0 0 0 0 0 1KP1 1778 0 0 0 0 0 0 0 38 0 0 0 731 0 0 390 0 0 0 0 618 0 0 0 0 0 0 KP 1609 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1609 0 0 0 3KP 328 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 328 0 0 0 0 0 0 0 0 PT 808 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 430 0 0 378 0 0 0 0 0 PT-7 2402 0 0 0 0 0 0 218 0 0 0 1079 0 0 564 0 0 540 0 0 0 0 0 0 0 0 0 PT-8 923 0 0 0 0 0 357 0 0 377 0 0 0 188 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-11 2238 0 0 190 0 0 0 0 0 376 0 0 0 446 0 0 0 0 309 0 0 916 0 0 0 0 0 PT-13 733 0 0 98 0 0 0 0 0 452 0 0 0 0 0 0 183 0 0 0 0 0 0 0 0 0 0 2KP 3533 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 541 0 0 0 0 208 34 884 1866 0 0 Sub-tot. [m] 15780 0 0 288 0 0 357 218 1004 1206 0 1079 731 634 564 390 724 540 1068 0 1082 1502 34 2492 1866 0 0 Tertiary pipes 1KP1-1 397 0 397 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1KP1-2 427 0 427 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1KP1-3 413 0 413 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1KP1-4 427 0 427 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1KP1-5 390 0 390 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1KP1-6 427 0 427 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1KP1-7 914 0 243 0 0 0 0 0 671 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1KP2-1 1386 0 355 0 0 0 0 0 503 0 0 0 529 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1KP2-2 1019 0 379 0 0 0 0 0 640 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1KP2-3 922 0 640 0 0 0 0 0 281 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1KP2-4 505 0 505 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 KP-1 1029 0 0 543 0 0 486 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 KP-2 677 0 0 237 0 0 440 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 KP-3 1695 0 0 0 0 0 403 0 0 0 0 0 0 1292 0 0 0 0 0 0 0 0 0 0 0 0 0 3KP-1 637 22 0 0 0 0 615 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3KP-2 824 0 0 301 0 0 523 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3KP-3 1124 0 0 465 0 0 659 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-1 459 0 0 423 0 0 0 0 0 36 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-2 367 0 0 367 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-3 921 0 0 0 0 0 0 0 0 0 0 0 0 921 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-4 291 0 0 291 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-5 876 0 0 0 0 0 876 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-7-1 290 0 0 0 290 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-7-2 267 0 0 0 267 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-7-3 302 0 0 0 302 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-7-4 398 0 0 0 398 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-7-5 146 0 0 0 146 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-7-6 257 0 0 0 257 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-7-7 284 0 0 0 0 0 0 284 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-8-1 260 0 0 260 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-8-2 271 0 0 271 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-8-3 271 0 0 271 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-8-4 926 0 0 191 0 0 543 0 0 192 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-10 613 0 0 0 0 0 307 0 0 306 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-11-1 549 0 0 549 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-11-2 261 0 0 261 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-11-3 550 0 0 0 0 550 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-11-4 253 0 0 0 0 253 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-11-5 565 0 0 0 0 565 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-11-6 257 0 0 0 0 257 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-11-7 247 0 0 247 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-11-8 628 0 0 628 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-11-9 1030 0 0 0 0 0 368 0 0 470 0 0 0 192 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-13-1 243 0 0 243 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-13-2 528 0 0 528 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-13-3 229 0 0 229 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-13-4 244 0 0 244 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-15 641 0 0 0 0 0 641 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PT-15-1 110 0 0 0 0 0 110 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2KP-1 415 0 0 0 0 0 0 0 0 415 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2KP-1-1 419 0 0 419 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2KP-1-2 347 0 0 347 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2KP-2 1340 0 0 429 0 0 164 0 0 0 0 0 0 0 0 0 747 0 0 0 0 0 0 0 0 0 0 2KP-2-1 813 0 0 532 0 0 281 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2KP-3 1080 0 0 518 0 0 563 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2KP-4 477 0 0 216 0 0 261 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2KP-5 226 0 0 0 0 0 226 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2KP-6 878 0 0 617 0 0 0 0 0 0 0 0 0 0 0 0 261 0 0 0 0 0 0 0 0 0 0 Sub-tot. [m] 32745 22 4604 9627 1660 1624 7465 284 2095 1420 0 0 529 2405 0 0 1009 0 0 0 0 0 0 0 0 0 0 Tot [m] 58433 22 4604 9915 1660 1624 7822 503 3099 2626 2069 1079 1260 4118 564 390 1749 540 1068 1611 1082 2238 61 2516 1868 4144 201

2.2 STEEL PIPES

2.1.10 General

The pipelines must be manufactured according to General Technical Specification requirements, as per clause 5.2.2. The pipelines are briefly described and quantified in Table 3-1.

Steel pipes and fittings shall be manufactured by a spiral or longitudinal weld process and shall conform to the requirements of EN 10224. Steel quality shall conform with EN 10025 grade S275JR. Outside diameters and wall thicknesses shall comply with EN 10024, where otherwise specified, with wall thicknesses as shown on the drawings.

Pipes shall either be coated externally when laid underground as per clause 3.2.2, or painted externally with epoxy lining of 400 micron in thickness when laid above ground, in ducts or inside buildings. In both cases they shall be internally lined at the manufacturer's works with either an approved epoxy-based or similar lining. The finished internal lining shall be continuous across all welded joints.

Pipes shall be supplied with plain ends either to fit flexible couplings or suitable for butt welding.

All pipes and specials to be joined by welding shall have the external protection stopped back at the ends at a distance sufficient to permit welding of the joints without damage to the protection, as further detailed hereafter.

For other than welded joints, the external protection shall, if necessary, be stopped back at a distance sufficient to permit assembly of the joint.

The internal protection shall extend to the end of pipes to be jointed by flexible couplings, and shall be stopped back as specified hereafter for pipes to be butt welded.

For pipes jointed by welding or by flanged joints, external protection shall be completed using the identical coating and lining material and material profile used on the main pipe barrel. Alternatively, the joint may be wrapped to a similar standard and thickness of protection using appropriate tape and paste or other protective material, all of which subject to the approval of the Engineer.

Straight pipes shall be supplied in nominal lengths of 12 m or as otherwise agreed with the Engineer.

Branches shall be formed by welding and shall be welded before the pipe is erected.

Pipe flanges shall be either “steel welding neck flanges” or “steel plate flanges for welding”, both conforming to up to 40 bar, or to other equivalent and approved standard, and welded on in accordance with UNI-EN 2277-2278 or to other equivalent and approved standard.

The pipes shall be supplied with plain ends, and should be coupled by butt welding according UNI-EN 10520, if not otherwise specified elsewhere.

2.1.11 Coating & Lining of underground pipe and Fittings

The steel pipes to be laid underground shall be coated as following specified:  Passive external protection of pipes and fittings shall be provided by the application of polyethylene and polyurethane-modified coating, respectively;  Internal protection of pipes and fittings shall be provided by the application of a liquid epoxy lining (400 microns dry thickness).

Save as otherwise prescribed by this Specification, the following Standards shall apply:  DIN 30670/91 (Polyethylene coating for steel pipes and fittings);  UNI 9099/89 (Steel pipes and fittings for buried or submerged pipelines - External polyethylene coating applied by extrusion);  DIN 30671/92 (Thermoset plastic coatings for buried steel pipes);  NF A 49-706/86 (Revêtement externe en poudre époxydique sur tubes);  NF A 49-709/92 (Pitch based polyurethane and epoxy painting for internal coating of steel water pipelines);  AWWA C210/92 (Liquid epoxy coating system for the interior and exterior of steel water pipelines);  ISO 527-3/95 (Plastics - Determination of tensile properties - Test conditions for films and sheets);  ISO 868/85 (Plastics and ebonite - Determination of indentation hardness by means of a durometer);  ISO 2808/91 (Paints and varnishes - Determination of film thickness);  ISO 4287-1/84 (Surface roughness - Terminology - Surface and its parameters);  ISO 8501-1/94 (Preparation of steel substrates before application of paints and related products - Visual assessment of surface cleanliness).

This Specification covers the minimum technical requirements for the preparation and application of the coating and lining of the steel pipes and fittings, and the Contractor shall submit fully detailed proposals of the coating and lining systems for the Engineer's approval.

The results of previous tests performed at the factory may be considered by the Engineer when reviewing the proposed coating and lining procedure; such results shall be made available to the Engineer well in advance of the start of coating and lining operations.

The Engineer may require delivery, at no cost to the Employer, of pipe sections coated and lined previously in accordance with the proposed procedure, for his inspection and approval. These pipe sections shall be chosen at random by the Engineer and shall be submitted to all the tests listed in this Specification.

All work at the coating and lining factory shall be subject to inspection by the Engineer who shall be given 30 days’ notice before the commencement of said work.

Any defective work shall be made good by the Contractor at no additional cost to the Employer.

The Engineer shall have the right to reject any and all tools, instruments, materials, staging, equipment, or work which do not conform with or impair the Specification.

Any rejected tools, instruments, materials or equipment shall be replaced or made good at no additional cost to the Employer.

2.2.1.1 Preparation of Metal Surfaces At the time of application of the coating and of the lining, the surface to be coated or lined shall be dry and free from soiling (such as previous coatings, paint and loose particles, grease, oil, salts, etc.) and surface defects (slivers, laminations, etc.) harmful to surface preparation or to adhesion. Abrasive blast cleaning shall be carried out to ensure suitable preparation of the external and internal surfaces of the pipe to be coated and lined. This treatment shall be carried out by the impact of an abrasive so as to obtain an overall surface condition corresponding at least to Sa 2½ as defined in DIN 55 928 Part 4. (Equivalent to SIS 055900 - Swedish Standard).

2.2.1.2 External Polyethylene Coating for Pipes (PE) The principle of this coating is that it shall consist of three layers: epoxy primer, adhesive, polyethylene according DIN 30 670/91. The coating shall be applied at the factory in accordance with the established procedure and in full compliance with the specifications of the manufacturer of the epoxy primer, adhesive and polyethylene. (a) Preheating Coating application may require preheating of the pipe as recommended in the specifications of the manufacturer of the epoxy primer, adhesive and polyethylene. Application temperature shall be less than 250°C. If the surface is affected by color change or contamination, the pipe shall be allowed to cool in air to ambient temperature and re-cleaned. Pipes heated above 250°C shall not be coated. (b) Layer 1

This layer shall be formed by a film of liquidepoxy resin or powder epoxy resin. If fusion-bonded powder epoxy is applied, particular care shall be taken to ensure that the temperatures required during the application process do not damage coatings and/or linings previously applied. The minimum dry thickness of the liquid epoxy and powder epoxy resin shall be respectively 30m and 60m. (c) Layer 2 This layer shall be formed by a polymer adhesive intended to provide adhesion between layers 1 and 3 and be compatible with those layers. The minimum thickness shall be between 150m and 200m, depending on the type of adhesive and the application. The thickness shall be uniform and shall be such as to satisfy the tests specified in DIN 30 670/91. (d) Layer 3 This layer shall be formed by the polyethylene coating. The thickness shall be uniform and the minimum total thickness shall satisfy the requirements of DIN 30 670/91. Pigments and additives may be added to the basic polyethylene, provided that all the required properties of the coating are obtained. Pigment shall be uniformly dispersed. When the coater adds pigments and additives to the basic polyethylene, the required properties must be certified by a documented quality programme. The following tests shall be undertaken, as a minimum: - quantitative analysis of the raw-material components before coating - determination of dispersion of pigments and additives.

2.2.1.3 Thickness of external Polyethylene Coating for Pipes (PE) Coating thickness shall be measured in accordance with the method defined in DIN 30670/91. The minimum thickness of the coating system at any point shall correspond to the values given below:  DN 500 mm pipe 2.5 mm  DN 600 to 750 mm pipe 2.8 mm  DN > 750 mm pipe 3.0 mm The thickness may be reduced by 10%, for welded pipes, at the weld reinforcement. For pipes laid in steep conditions, the minimum thickness of the coating shall be 3.5 mm, as instructed by the Engineer.

2.2.1.4 Composition and Application of Internal Epoxy Lining Lining material shall be liquid epoxy, solvent free, of the two component type. It shall also satisfy all current applicable health and safety requirements with regard to suitability for use in potable water services.

The principle of this lining is that it shall consist of one layer of epoxy resin. The lining shall be applied in the factory in accordance with the established procedure and specifications of the manufacturer. The content of technical data sheets and certificates of materials for liquid epoxy lining shall be submitted to Engineer for approval. (a) Mixing Resin and hardener shall be supplied in separate containers. Each pack shall be stirred or agitated to a homogeneous state before any material is withdrawn from its container. Resin and hardener shall be thoroughly mixed in the proportions specified by the product manufacturer. The two packs shall be supplied in different colours, if possible, and evidence of complete mixing shall be when a uniform colour is achieved without any "streaking". The quantity of material made up at one time shall not exceed that which can be used within the pot life stated by the product manufacturer or that necessary to ensure complete coverage of the area to be coated. (b) General application procedure Immediately after the abrasive blast cleaning, a layer of liquid thermosetting lining shall be applied by brush, by the airless spray technique or by other methods in accordance with the product manufacturer’s instructions. Particular care shall be taken to avoid damage to the liquid epoxy lining if applied prior to other coatings which might require high processing temperatures. Lining shall be carried out using the equipment recommended by the manufacturer. The lining shall be uniform. If a second layer is required to reach the specified thickness, this shall be applied in accordance with the over coating time prescribed by the product manufacturer. Wet thickness shall be measured according to ISO 2808/91. Particular attention shall be paid to the recommended dry film thickness, which shall be measured in accordance with the method defined in UNI 9099/89. If pre-heating of one or more of the coating material packs prior to mixing and application, or a post-heating of the coating after application, is required, this shall be done according to the product manufacturer's recommended procedure. No thinners shall be used unless recommended by the product manufacturer and tools and equipment shall be cleaned using only such solvents as are recommended by the product manufacturer.

Particular care shall be taken in the handling of the components before the coating has reached the minimum value of the hardness recommended by the product manufacturer.

2.2.1.5 Dry thickness Internal Epoxy Lining Lining thickness shall be measured in accordance with the method defined in UNI 9099/89. The dry thickness of the lining system at any point shall correspond to 400m  25m.

2.2.1.6 Inspection (a) Documentation Inspection operations shall be carried out by the coater and liner as agreed at the time of procurement and submitted to the prior written approval of the Engineer. A representative appointed by the Engineer may witness these operations. The results of these inspection operations shall be recorded by the coater and liner and shall be made immediately available to the Engineer. (b) Sampling The Engineer’s representative shall select the pipes on which the specified tests shall be carried out. The test pieces for destructive testing shall be taken, if possible, from the ends of the pipes. Samples and the test pipes shall be marked in order to be fully and easily identifiable. (c) Unit of product and material traceability A unit shall be taken as meaning a set of pipes coated and lined under the following conditions: - the same type of manufacturing technique and same production line - the same outside diameter and same thickness of pipe - the same production run - the same production batch of material. (d) Nature and frequency of testing and control The nature and frequency of the testing and control on factory shall be as stated in DIN 30670/01. The procedures and frequency for the testing of the field lining of the internal and external surface shall be submitted to the prior approval of the Engineer. (e) Marking Each pipe and fitting shall be uniquely marked ; the marking shall include the following:  identification;  code or name of the producer of the steel ;  applicator code, if it differs from the preceding code;

 reference to the steel standard;  reference to this Specification followed by the thickness of the pipe wall, of the coating and of the lining, in this order. Marking shall be carried out using a suitable method such as stencil painting or printing, making legible and indelible identification possible, using durable materials compatible with the subsequent use of the pipes and components.

2.2.1.7 Field Completion of the Internal Epoxy Lining at Welded Pipe Joints (a) General This part of the Specification shall govern the surface preparation, material application and inspection requirements for the field completion of the internal epoxy lining, at welded pipe-joints. The details given herein shall be construed as minimum guidelines only and the Contractor shall submit for the Engineer's approval a fully detailed system for field completion of linings. Lining applied in the field shall be carried out in compliance with the liquid epoxy manufacturer’s recommendations. All work shall be subject to inspection by the Engineer who shall be given 7 (seven) days notice prior to its commencement. The Engineer shall have the right to condemn any and all tools, instruments, materials, equipment or work which does not conform to the Specification. Any condemned lining application or any defective work shall be replaced or rectified by the Contractor at no additional cost to the Employer. In cases where the Contractor wishes to deviate from this Specification, all relevant details concerning materials, components, equipment, application and testing procedures, and remedies, shall be submitted for the Engineer's approval. Proposals for changes shall be made within such time that should said proposals not be approved by the Engineer, the work, when executed in full accordance with this Specification, shall not affect or delay completion of the Works. (b) Raw material The material utilized shall be liquid epoxy applied cold by spraying in such manner as to produce an effective bond with the underlying steel. It shall also satisfy all current applicable governmental health and safety requirements with regard to suitability for use in potable water services and shall be fully compatible with the epoxy previously applied in the factory to line the internal surface of the pipes and fittings. (c) Joint lining (i) Preparation of the internal pipe joint surface before joint welding

All corrosion products and any pre-existing lining shall be removed from the internal pipe surface for a length of 150 to 200 mm from the pipe edges until the metal surface is clearly visible and dry. The metal surface shall then be thoroughly cleaned by scraping and wire-brushing or sand-blasting. The surface shall have a pronounced metallic sheen and correspond to C St 3 of ISO 8501-1/94. (ii) Preparation of the internal pipe joint surface after joint welding All sharp edges on welds shall be removed. The surface to be lined shall be roughened with a wire brush. The adjacent lined surface shall also be lightly roughened. All traces of dust and of loose or foreign particles shall be removed using a suitable aspirator. (iii) Lining of the internal pipe joint surface after welding The lining shall be applied by a suitable system (e.g. cross-spraying) in such a way that the resulting film shall not be so heavy that it will run on vertical surfaces. An appropriate number of layers shall be applied to obtain the dry film lining thickness specified hereafter. Each layer shall provide an effective bond between the preceding and the subsequent layer. The lining shall overlap the main body of the pre-existing lining on each side of the weld, for a length of at least 50 mm, to form a continuous lined surface free from defects. (iv) Lining thickness The dry film thickness shall be 450  m ± 25  m. The dry film shall be uniform and shall not contain bare spots or holidays. (d) Testing and inspection The procedures for the testing of the field lining of the internal surface of welded pipe-joints shall be submitted to the prior approval of the Engineer. (i) Test samples The Engineer may require delivery (at no cost to the Employer) of samples of internally lined welded joints, having a length of approximately 1m, cut from welded pipe sections, for his inspection and approval. The Engineer's representative may require to be present at the welding, internal lining of pipe-joints and cutting of the samples. During construction of the pipeline the Engineer may, at no cost to the Employer, require cutting of a joint sample every 2000 welded joints and performance thereon of the following internal joint surface lining tests, to check:

a) length of overlap between the joint lining and the pre-existing lining b) lining uniformity c) lining thickness d) bond between linings e) adherence of the lining to the underlying metal f) surface preparation. If the results of one of these tests fails to meet any of the specified requirements, two additional joint samples shall be cut every 2000 completed joints after the preceding satisfactory test. If the results of one of the tests on one of these joints do not meet the specified requirements, the Contractor shall cut an additional two joints and so forth. (ii) Lining thickness Lining thickness of field lined joints shall be assessed on the basis of the quantity of material sprayed per square meter of lined surface. Lining thickness of joint samples shall be evaluated as the mean of the thicknesses measured in 10 randomly selected points. In all cases, each thickness value shall not be less than 425 m. Dry film thickness shall be measured by a non-destructive test instrument (e.g. Elcometer, Mikrotest). (iii) Adhesion Adhesion tests shall be performed in accordance with the requirements of AWWA C210/32 (V-cut adhesion). (iv) Holiday detection The procedures for the performance of the holiday detection test shall be proposed by the Contractor and shall be subject to the approval of the Engineer. The test shall be considered satisfactory if the lined joint surface does not give rise to any defects. If the test has failed, the Contractor shall apply another layer to the lining and a further test shall be carried out until the test is satisfactory.

2.2.1.8 Field Completion of the External Coating at Welded Pipe Joints The Contractor shall provide full details of the materials and methodology to be utilised for the completion of the external coating at welded pipe joints, so as to ensure compatibility with, and protection characteristics not inferior to, those required for the external coating of the tubes, all of which shall be subject to the prior written approval of the Engineer who may also require prior testing on welded joint specimens.

2.1.12 Handling Transportation and Storage of Coated and Lined Steel Pipes and Fittings

Handling : Pipes and fittings shall be handled so as not to cause damage to chamfers or coating or lining. The direct use of steel or hemp slings or of any equipment of a shape or nature likely to damage to the coating or lining is prohibited. Coated and lined pipes shall be handled using aluminum, brass or padded end hooks, wide non-metallic slings or padded calipers, taking such care as required to ensure their integrity at all times. Separation of pipes during transport: Suitable precautions, such as padding placed horizontally and vertically, shall be taken to ensure that pipe coatings are not damaged during transport. Trucking : Suitable hauling equipment shall be provided to minimize coating damage. All chains and pipe supports shall have sufficient padding between them and the coated pipe to prevent damage. Binders, straps and belts shall be padded where required. Truck trailers shall be free of obstructions which may cause damage to the coated pipe. Rail transport: The bottom of rail cars shall be cleaned so that they are free of any obstructions which may cause damage to the coated pipe. Rail transportation of coated pipes shall be in conformity with API Recommended Practice 5L1 (RP5L1), Third Edition, April 1972. Marine transportation: Marine transportation of coated pipes shall be in conformity with API Recommended Practice RP 5L5, First Edition, March 1975. Storage: Storage areas shall be free from rocks, stones, sticks and other protrusions, and shall be well drained. The contact area of skids shall be padded, e.g. with rubber, canvas, belting, pressed fiber board, etc. A padded wedge shall also be used to prevent side-roll movement of bottom row pipes. A suitable covering shall be provided to coated pipes for their protection from ultraviolet deterioration when pipes are expected to be stored or exposed in the open for a period of 6 months or more. At all times storage conditions shall be such that each pipe and fitting is not in direct contact with the ground and the coatings and linings are not damaged in any manner.

2.3 HDPE PIPE

The pipelines must be manufactured in according General Technical Specification requirement, as per clause 5.2.2.3.

The pipes shall be supplied with plain ends, and should be coupled by butt welding according UNI 10520, if not otherwise specified elsewhere.

2.4 FITTINGS

2.1.13 Steel elbow

The pipelines must be constructed on site as is indicated in drawings. The material, diameter and wall thickness of the steel elbow shall be the same as the pipes to connect with and shall comply with the General Technical Specification requirement, as per clause 5.2.2.2. Connection of steel elbows to the pipe to connect with shall be butt welding and shall comply with the General Technical Specification requirement, as per clause 5.2.2.2. Steel elbow shall not be measured as a separate item and shall be deemed fully included in the unit price of steel pipe.

2.1.14 HDPE elbows

The elbows must be manufactured according clause 5.2.2.3 of General TS.

Elbows shall be supplied with plain ends suitable for welding. The elbows shall be manufactured according UNI EN 12201-3, and the welding coupling shall be according UNI 10520. The shape, dimensions and sizes of all the fittings shall be as shown on drawings.

2.1.15 HDPE reduction

The reduction must be manufactured in according clause 5.2.2.3 of General TS.

Reductions shall be supplied with plain ends suitable for welding. The reductions shall be manufactured according UNI EN 12201-3, and the welding coupling shall be according UNI 10520. The shape, dimensions and sizes of all the fittings shall be as shown on drawings.

2.1.16 Steel flanged reduction

The reductions must be manufactured in according clause 5.2.2.2 of General TS. Steel reductions shall be welded to steel flat flanges, according UNI-EN 15614-1. The shape, dimensions and sizes of all the fittings shall be as shown on drawings.

2.1.17 HDPE Tee piece

The tee piece must be manufactured in accordance with clause 5.2.2.3 of General TS.

Tees shall be supplied with plain ends suitable for welding. The HDPE Tee fittings shall be manufactured according UNI EN 12201-3, and the welding coupling shall be according UNI 10520. The shape, dimensions and sizes of all the fittings shall be as shown on drawings.

2.1.18 HDPE flange adaptor

The flange adaptor must be manufactured in according clause 5.2.2.3 of General TS.

The flange adaptors shall be supplied with plain ends suitable for welding. The adaptors shall be manufactured according UNI EN 12201-3, and the welding coupling shall be according UNI 10520. The shape, dimensions and sizes of all the fittings shall be as shown on drawings.

2.1.19 Steel flanged Tee/Cross

The steel tees must be manufactured in according clause 5.2.2.2 of General TS. Steel tees shall be welded to steel flat flanges, according UNI-EN 15614-1. The shape, dimensions and sizes of all the fittings shall be as shown on drawings.

2.1.20 Steel flange

The steel flanges for stub end must be manufactured and jointed according UNI-EN 1092. Steel flanges shall be supplied with all connecting components: bolts, nuts, washers, gasket. The shape, dimensions and sizes of all the flanges shall be as shown on drawings.

2.1.21 Special flanged HDPE T-piece

The special flanged T-piece will be used to construct hydrants as is indicated in drawings. The connection to the HDPE pipeline is by but welding. Material will be HDPE 100. The flanged branch of T-piece will be of 100 mm in diameter and will be used for connection to the flanged hydrant riser of 100 mm in diameter. The flange material shall be of HDPE 100 or Steel.

2.1.22 Special flanged pipes

The flanged steel pipes must be manufactured in according clause 5.2.2.2 of General TS. Pipes shall be welded to steel flat flanges, according UNI-EN 15614-1.

2.1.23 Double flanged steel pipes for hydrant risers

The flanged steel pipes must be manufactured in according clause 5.2.2.2 of General TS. Pipes shall be welded to steel flat flanges, according UNI-EN 15614-1. The diameter of pipe will be of 100 mm. Flanges will be attached by welding to both end of the pipe. The length of riser shall be at least 50 cm above the ground level. On top of the hydrant riser the hydrant valve and a Signalling rod will be installed as indicated on the drawings. Drawings, Method of manufacturing and Connection to the underground pipes shall be approved by the Engineer before ordering.

2.1.24 Special hydrant valve

The hydrant valves will be of 100 mm or 150 mm in diameter as indicated on drawings. Material can be of HDPE 100 or steel or aluminum. The hydrant valve shall be approved by the Engineer before ordering. Sample of hydrant valves and connection to the irrigation equipment shall be submitted to the Engineer, for approval. The special hydrant valve will be installed on top of hydrant risers and will be used for connecting irrigation equipment. The irrigation equipment will be provided by water users. The irrigation equipment will be provided with adequate valve connection and will allow opening the hydrant valves. The hydrant valve shall be of NP 10 and will be provided with adequate gasket to provide water tightness while in close position.

2.1.25 Hydrant

Hydrants shall be installed on tertiary pipelines every 50 m. First and last hydrant shall be installed as is indicated in drawings. The hydrant shall consists of one riser as per clause 3.4.12 of Particular Technical Specifications equipped with one special hydrant valve as per clause 3.4.13 of Particular Technical Specifications. The hydrant riser shall be connected to the tertiary pipeline by special flanged HDPE T-piece as per clause 3.4.10 of Particular Technical Specifications. All components of hydrant shall be of nominal pressure 10 bar (NP 10). The height of hydrant shall be sufficient to exceed the ground elevation by 50 cm and shall be equipped with a warning rod as indicated in drawing. Method of installation, materials, fittings and connecting fasteners shall be approved by the Engineer before ordering.

2.1.26 Air valves

Air release shall be of automatic float type designed to release accumulated air in the water pipeline under pressure and to allow air entering into pipelines for dewatering or in case of negative pressure. The dimensions and capacity shall be those specified in drawings. Air valves shall be installed above the ground level of at least 100 cm and shall be equipped with a warning rod as indicated in drawings. After releasing the air he valve shall provide water tightness for minimum pressure of 1 bar and maximum pressure of 10 bar.. The valve will be NP 10. Method of installation, materials, fittings and connecting fasteners shall be approved by the Engineer before ordering.

2.1.27 Washout

The washout shall be installed on all pipelines to allow dewatering of pipeline for repair or before cold season. The location of washouts is indicated in the drawings. The steel double flanged drain pipe shall be of DN 80, NP 10. For dewatering the pipe a mobile diesel pumping unit of 5.5 CP/3600 rpm, suction depth of minimum 4 m, discharge pressure of min 3 bar, equipped with flexible suction hose and mobile hand moving lateral for discharge the water over the irrigation area. The flexible suction hose shall be of 80 mm in diameter and shall have enough stiffness to maintain its original shape of cross section at negative pressure up to 0.8 bar and enough flexibility to allow connection to the drain pipe of the washout. The discharge lateral shall be equipped with 10 sprinklers of impact type of 0.8 l/s each. The length of lateral shall be at least 120 m and shall have a minimum diameter of 80 mm. The material of hand moving lateral shall be HDPE 80 or aluminum. Two brand new mobile diesel pumping units equipped as described above shall be procured and handed to WUA management for use during operation for dewatering of the irrigation network before cold season or for dewatering of any pipeline for repairing. Equipment, materials, fittings and connecting fasteners shall be approved by the Engineer before ordering.

2.5 VALVES

2.1.28 Valves - general

EN Standards have generally been referred to in this Specification. Any other equivalent national or International standard` may be used, subject to the Engineer's approval.

All valves shall be best waterworks quality and shall be suitable for use with water or waterworks sludge at temperatures of up to 45o C.

Valve bodies shall give the following information: manufacturer's name hydraulic test pressure size of valve direction of flow ‘arrow’ (where flow in only one direction is permitted).

The operating gear of valves shall be such that one person can open and close the valve against an unbalanced head 15% in excess of the maximum likely to be encountered in service.

Gate valves shall be provided with renewable seats. Gates shall be capable of being removed without removing the valve body from the pipework.

All valves shall have a pressure rating as designated on the drawings, the rating of a particular valve being equal to or greater than the maximum working pressure (including surge) to which the valve may be subject under pipeline operational conditions.

The operation of all valves shall be such that they are closed by turning the hand-wheel or tee-key in a clockwise direction. The hand-wheel or tee-key shall be large enough to allow operation by one person.

All materials shall comply with the appropriate EN Standards and shall be subject to the Engineer's approval. All castings shall be free of blowholes and other defects.

All standard valves shall be suitable for frequent operation, and for infrequent operation after long periods in the open or closed condition, and shall satisfy the requirements of the open and closed end tests.

Butterfly valves shall be installed in the pipework in such a manner that they can easily be removed from the line for dismantling and replacement of the seats and seals, and shall be designed to give minimum leakage. Check (non-return or reflux) valves shall possess high speed closing characteristics, with minimum shock on closing.

(a) Gate valves Gate valves shall be of the double-flanged ductile iron or steel wedge-gate type, unless otherwise specified, and shall have a ductile iron or steel body with renewable non-ferrous faces on body and wedge and a bolt-on cast iron or steel bonnet to facilitate gate removal. Valve spindles shall be of the internal, non-rising type. Valves shall carry identification marks and/or plates in accordance with the British Standard, stating the valve identification and giving a brief description of its functions. Inscriptions shall be in the English language. The valve manufacture shall conform to the following standards: ISO 7259; hydrostatic test according to ISO 5208; Face to face dimension according to ISO 5752 series 15 DIN3202 part 1 series F4; flanges according to ISO, ISO 7005-2, DIN 2501. All materials used in the manufacture of the valves shall conform to the following minimum standards or other equivalent and approved standards: Materials of Construction: Body and cap: Ductile iron GG50 to DIN 1693 Bolt and clamp: Ductile iron GG50 to DIN 1693 Gate: Ductile iron GG50 to DIN 1693 Operating stem: Stainless steel Operating nut: Brass Bush: BronzeBody-cap joint: EPDM Surface protection Body and cap: Epoxy powder thickness minimum 250 microns; Bolt and clamp: Thermoplastic resin; Gate: EPDM.

(b) Butterfly valves Butterfly valves double flanged shall conform to ISO 5752S, or equivalent and approved standard, and shall be to the pressure ratings stated on the Drawings. Except as otherwise specified, all butterfly valves shall be resilient-seated and shall give tight closure against unbalanced water pressure in either direction. The unbalanced water pressure shall be the design pressure rating of the valve. The valve seat shall be replaceable and be formed of rubber or other approved resilient and durable material. The valve seat shall be securely clamped into a machined groove on the valve body or to the edge of the disc by a seat retention device, so as to prevent leakage of water under the seats and to hold the seat securely in position during opening and closing of the valve disc. Disc edges shall be machined with rounded corners and be polished to a smooth finish. The valve disc shall rotate through an angle of 90 degrees from the fully-opened to the fully closed position and the seat shall be of such design as to allow the valve disc to seat at an angle normal to the axis of the pipe when the disc is in the fully-closed position. The shaft shall be fabricated of stainless steel and may be in one piece or attached as two stub ends on opposite sides of the disc. The means of attachment of the shaft to the disc shall be fixings of a homogeneous corrosion-resistant material to a pattern which precludes the assembly becoming loose in service. The shaft and disc fixing shall be capable of absorbing full operating torque with a minimum design safety factor of 5. Shaft seals, when used, shall be of the rubber O-ring type. Packing shall be either of the ribbed O-ring or self adjusting chevron type. The Contractor shall provide details of the design and materials for the manufacture of butterfly valves, and shall provide evidence to show that the proposed seating design and materials have given satisfactory performance in conditions similar to those applying under the Contract. Valves shall carry identification marks and/or plates. The butterfly valve manufacture shall conform to the following standards: BS EN 593, EN 1074, DIN 3354 parts n° 1 and n° 2; Face to face dimension according to ISO 5752 series 14 DIN3202 part 1 series F4; Flanges according to ISO 2531-1998, EN 1092-2, BS 4504, ISO 7005-2; drilling according to table 8 ISO PN 10; hydrostatic test according to ISO 5208. All materials used in the manufacture of the valves shall conform to the following minimum standards or other equivalent and approved standards: Materials of Construction: Body: Ductile iron, GG50 to DIN 1693 Disc: Ductile iron, GG50 to DIN 1693 Disc seal: EPDM Disc seal retaining ring: Carbon Steel Shafts: Stainless Steel AISI 420B Bearing: Bronze

Shaft gasket cover : Bronze CuSn5Zn5Pb5 CC491K to BS EN 1982 Shaft cover: Steel Shaft pin: Stainless Steel 630 Ring: Bronze CuSn5Zn5Pb5 CC491K to BS EN 1982 Retaining ring fixing screws: Stainless steel AISI 304 Seat: Stainless steel AISI 304 L Outside construction bolting: Steel galvanized class 8.8. Surface protection Inside and outside (including disc and sealing surface of flanges): fusion bonded epoxy, minimum DFT of 300 microns (c) Check valves (non-return or reflux) Check valves shall comply with BS 5153 or equivalent and approved standard and be double- flanged cast iron or steel, unless otherwise specified. They shall be of the quick acting, non- slam single or multi-door type designed to minimize slam on closure by means of heavy, gunmetal-faced doors, weighted as necessary and provided with stainless steel hinge pins. Valves shall carry identification marks and/or plates in accordance with BS 5153. They shall have flanges to BS 4504 up to NP 40, or to other equivalent and approved standard for higher pressure ratings. All materials used in the manufacture of the valves shall conform to the following minimum standards: Cast Iron BS 1452 Grade 220 Gunmetal BS 1400 Grade LG2 Stainless Steel BS 970 Pt. 4 Grade 431 S29

______Section IX. Specifications – Lot #1 / CIS ‘Jora de Jos’ 28 Rehabilitation Works on CISs along Nistru River IFB #PP6/THVAP/W/CB/03 Millennium Challenge Account – Moldova or other equivalent and approved standards.

2.1.29 Setting of Valves, etc.

Care shall be taken to prevent damage to all valves, hydrants and penstocks and their ancillary equipment. Where directed, headstocks, motors, gearing or indicators shall be removed, adequately labelled for identification, stored carefully in weather-proof premises and be reconnected when required.

Drain cocks shall be kept clean and free from obstruction. Electrical equipment shall be protected from damp; damp-proofing seals shall remain intact until the equipment is finally connected.

Gunmetal faces and seats of all valves shall be kept clean. No valve shall be closed unless the faces have first been wiped clean. The cavity beneath the valve door shall be thoroughly cleaned by hand. In the event of accident, fouling matter shall either be dissolved or carefully removed by an approved method that shall not involve scraping of the gunmetal faces.

Where gate valves are supplied with scour plugs screwed into the bottom of the valve body (or into a cleaning door studded to the bottom of the valve body), the plug shall be left out when the gate is shut for the first time on Site. When the gate has been set down on the seat, the plug shall be screwed up to make contact with the underside of the gate and shall then be turned back to clear the gate. In no case shall a plug be inserted without ensuring that the gate clears the plug on closing.

All valves shall be set so that operating spindles are truly vertical unless otherwise detailed or directed. Spindles shall turn anti-clockwise to open, unless otherwise required.

Before each valve is put into service, all gears, bearings and spindles shall be lubricated as recommended by the valve maker. Oil baths shall be topped up to appropriate levels and all grease nipples charged with grease of approved manufacture. No deleterious matter shall be allowed to come into contact with the working faces and oil sumps shall be maintained clean. Each stuffing box shall be examined when the main is charged with water, and leaking boxes shall be adjusted or replaced with square-plaited lubricated hemp packing of approved manufacture. The stuffing box shall not be packed so tightly that it materially affects the operation of the valve by friction of the packing on the spindle.

Air valve shall not be stored upside down exposing the balls and air cavities. Air valves shall be checked before the main is charged to ensure that the balls and faces are not scored or split and that there is no dirt or other deleterious matter in the cavities of the body. All air nozzles shall be probed, with approved probes, to ensure their cleanliness.

The installation of special types of valve and metering equipment shall be strictly in accordance with the manufacturer's instructions.

Valves and ancillary equipment shall be stored in a clean condition in a tidy and weather- proof store, and shall only be installed in their positions when adequate security and protection from the weather are possible.

2.1.30 Gaps for Valves, hydrants, Air valves,

If a delay, or other valid reason, in the delivery of valves or specials shall make it necessary for temporary gaps to be left in pipelines, the Engineer's approval shall be sought prior to the commencement of each such pipeline. The Contractor shall submit dimensioned sketches to the Engineer for approval, showing details of the pipe and jointing arrangements to be adopted to effect ultimate closure. Care shall be taken to preserve the accurate alignment of the pipeline across all such temporary gaps.

3. DETAILED ELECTROMECHANICAL AND ELECTRICAL WORKS FOR PUMPING STATION SPP-1

3.1 INTRODUCTION

3.1.1 General description of the SPP-1 pumping station

The SPP-1 pumping station is located on right bank of the Nistru River, 1 km downstream Jora de Jos village. The pumping station is a pressure pumping station and serves for in- taking water and delivering it to the irrigation network. The total rated flow is 219 l/s at 79 m. The facilities consist of the main following equipment:  Upstream the pumping station: o Water intakes in the river; o The connecting pipes between the intakes and the pumping station;  In the pumping station: o The pumping units; o The pipes and fittings; o The valves: suction gate valves, discharge gate valves, non return valves, flushing gate valves; o Ancillaries: vacuum pumps, dewatering pumps, compressors, handling devices, ventilation, heating, etc.; o Low voltage electrical switch gears; o Instrumentation and metering devices;  Downstream the pumping station: o The connecting pipes between the pumping station and a flow-meter chamber; o The flow-meter chamber.

3.1.2 General principle of operation

The operation of the pumping station will be fully automatic, without requiring intervention by operating staff, except for contingencies, maintenance, repair, etc. and for the first filling of the network, by manual operation. An initial start of a pump, after the network is filled, is also manual and manual refilling of the system following electric power interruption during operation may also be required. It will be mainly controlled by adjusting the pressure according to the water flow in the network. Emergency operation of the pumping station in manual mode will also be possible in case any of the components for automation are out of order.

The command, the number of pumps needed and their speed are determined according to the water flow measured by a flow meter installed in a chamber downstream the pumping station. The pumps will automatically shut down above a maximum pressure and below a minimum pressure in the network and below the minimum water level in the river.

In case of failure, an alarm will be recorded and transmitted by SMS through the GSM network to on-call personnel of the Operator.

3.1.3 Scope of Work

The main hydro- and electro-mechanical works comprise of:  Dismantling of existing water intakes with fish protection devices in the river;  Installation of a new water intakes with fish protection devices in the river;  Dismantling of 3 existing pumping units;  Installation of 2 new pumping units;  Dismantling of the existing vacuum system;  Installation of a new vacuum system, including 2 vacuum pumping units, a water tank, pipes and valves;  Installation of a new dewatering system, including 2 dewatering pumping units, pipes and valves;  Installation of a water hammer protection system, including 2 compressors, a pressure vessel, pipes and valves;  Dismantling of existing pipes and fittings between the fish protection device and the river bank, at the pumping station inlet, in the pumping room and between the pumping station and a flow-meter chamber outside the pumping station;  Installation of new pipes and fittings between the fish protection device and the river bank, at the pumping station inlet, in the pumping room and between the pumping station and a flow-meter chamber outside the pumping station;  Dismantling of 2 existing suction gate valves and 2 existing discharge gate valves;  Installation of 2 new suction gate valves, 2 new discharge gate valves and 2 non return valves in the pumping room;  Mechanical and electrical overhaul of the handling device and change of wearing parts;  Installation of 2 air inlets and 2 fans in the pumping room and 1 air inlet and 1 fan in the electrical room;  Installation of 2 flushing gate valves in a manhole outside the pumping station.

The main electrical works comprise of:

 Dismantling of 7 existing main low voltage electrical switch gears and ancillaries’ switch gears;  Installation of 5 new main low voltage electrical switch gears, including an automation and remote control switch gear;  Installation of the interface equipment (electricity counter and auxiliaries) to the power supply company;  Dismantling of the existing lights and sockets equipment;  Installation of a new lights and sockets equipment;  Dismantling of the existing cables and cable trays;  Installation of new cables and cable trays;  Dismantling of the existing grounding system;  Installation of a new grounding system;  Dismantling of the existing lightning protection system;  Installation of a new lightning protection system.

The main automation and SCADA works comprise of:  Dismantling of the existing instrumentation and metering equipment;  Installation of new instrumentation and metering equipment, including a flow-meter;  Installation of a Programmable Logic Controller (PLC) and a Remote Terminal Unit (RTU) at the pumping station;  Installation of a remote control centre at the location defined by the contractor, including a working station with a SCADA software and a printer;  PLC programming;  RTU programming;  SCADA working station programming.

The works also comprise of:  Commissioning of the facilities;  Providing the Operator with O&M manual and as built drawings;  Training of the operating staff.

The Contractor is obliged to bring the dismantled equipment to the warehouse of STI Orhei located in the town of Orhei, 74 Unirii street, which is located at an estimated maximum one way distance of 32 km. Material (i.e. PTC containing oil), which could have negative impact to the environment, must be designated and special treated accordingly.

The particular specifications of the new equipment to install are detailed in the following chapters. The general specifications of this equipment are detailed in the Technical Specification booklet. Other design information is available on drawings.

3.2 HYDRO- AND ELECTRO-MECHANICAL EQUIPMENT

3.2.1 Intake structures

The Contractor shall build and install on the suction pipe heads, ecologic hydraulic fish- protection devices of umbrella type– one device per line as is indicated on the drawings. The diameter of fish protection device is calculated based on the rated flow of 138 l/s and an inlet velocity of 0.1 m/s. A structure of ND 1,600 mm is providing the water inflow through lateral sides of 0.30 m width. The suction pipe ND 350 mm enters into a metal shell of ND 1000 mm diameter and of 800 mm height. The pipes shall be butt-welded to the metal shell.

The top elevation of the umbrella-type fish protection device is determined based on its location below the minimum water level in the river which is equal to 26.50 m above the Baltic Sea. Taking into account the potential ice thickness and a reserve, the corresponding top elevation of the umbrella is assumed to be 25.70 m above the Baltic Sea.

The type and size of the fish-protection devices and structures is agreed with the Fishery Service, under the Ministry of Environment.

In order to reach a greater depth of water, the fish protection devices will be shifted some 100 m towards the centre of the river as shown in the detailed drawings. The new pipes will be welded to the existing one and will be installed to the depth indicated in the longitudinal profile, requiring for this to excavate the layer of sediment accumulated during the years after the entering of operation of the Dubasari dam. The layer of sediment is estimated to be approximately 1.0 to 1.5 m thick but the Contractor shall make his own estimation of the nature of the sediment and/or of the river bed materials. No claim will be accepted for any deviation from the above indicative values.

Pipes will be laid on or below the original river bed. In no case inversion of slopes will be permitted to avoid accumulation of air in the suction pipes. Deviations from the actual slopes shown in the drawings can be permitted but only if authorised by the Engineer to better cope with the actual field situation.

Underwater excavation works will be carried out in accordance with the general provisions of the GTS.

Excavated material will be dumped in the water at the indicative location shown in the map overleaf which was based on a bathimetric survey carried on in May-June 2012.

The material shall be dumped in any case below elevation 22.00 (Baltic Sea System) and in layers not exceeding 0.50 m. The Engineer may require the Contractor to prove by underwater survey that the above conditions are met, and to remove all materials dumped irregularly.

Methods to be used for executing the underwater excavation and for laying the pipes and the fish protection devices shall be included in the Contractor bidding documents as well as before any actual work will start.

Information to be provided include:  List and specification of main equipment to be used for dredging and for disposing the excavated materials  List and specifications of the ancillary equipment to be used such as pontoon, etc.  Planning of the works taking into account the following monthly average water elevations

______Section IX. Specifications – Lot #1 / CIS ‘Jora de Jos’ Rehabilitation Works on CISs along Nistru River IFB #PP6/THVAP/W/CB/03 Millennium Challenge Account – Moldova

3.2.2 Pumping units

The output of the hydraulic calculation states a total flow of 219 l/s at 77 m. Taking into account usual head losses in a pumping station of about 1.5 m and an additional head loss of 0.5 m for the intake device, the rated pumping head is 79 m.

The total flow of the pumping station is split into 2 pumps. There is no stand-by pump. The rated point of each pump is thereby 110 l/s at 79 m.

The pump is of axial split case type, horizontally mounted, with dual flows’ radial impeller. The design pressure is not less than 16 bars. The pump velocity is not more than 1,500 rpm.

The pump casing is in gray cast iron (GG-25). The impeller is in stainless steel (austeno- ferritic / duplex steel). The pumps’ sealing type is gland packing with square cross-sectioned rope.

The pumps’ ball bearings are greased for life. They are fitted with digital thermal probes to detect unusual heating.

The following diagram indicates the pumping network curve with an example of pumps’ curve.

H (mWC) Pump Diagram - Group 1: Jora de Jos SPP-1 100 Qmin Network max. curve 90 1 pump 1500 tr/min

80 2 pumps 1500 tr/min

1 pump 1248 tr/min 70 Network min. curve 60

0 Q (l/s) 0 0 0 0 0 0 0 5 0 5 0 0 5 1 1 2 2 3

The mathematical equation of the network curve resulting from the hydraulic simulation is: H=0.00026xQ²-0.0031xQ+67.2 (at Min. water elevation H90%). The equation of the network min. curve is: H=0.00026xQ²-0.0031xQ+64.6 (at Max. water elevation H5%).

The Contractor shall update the pumping diagram according to the characteristics of the proposed pumps and define the corresponding technical requirements, including electrical values (motors’ power, contactors’ calibration, etc.).

The hydraulic efficiency of a pump is not less than 75% for all the range of operation, whatsoever with 1 or 2 pumps simultaneously in operation at fixed speed. The pumping station is design to operate between 20% and 100% of the nominal capacity. The suction capacity of the pump NPSHr shall not be above 5.7 m for all the range of operation, and particularly with a single pump in operation, at a flow around 138 l/s.

The pumps motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 80 K, degree of protection IP55, natural cooling with fan. The rated motor efficiency is according to IEC 60034-30 class high efficiency IE2. The pump constructor shall supply the motors: the proper operation of the whole pumping unit (pump + motor) is under the responsibility of the pump constructor.

The motor power is selected taking into account the system efficiency and a security factor of 10% above the restrictive functioning point. In the present case this is with a single pump in operation according to the above diagram. The calculated rated motor power is thereby 149 kW. The actual rated power according to constructor standard will not be less than this value. The Contractor shall update this calculation according to the actual hydraulic efficiency of the proposed pump and offer the corresponding motor standard size. The calculation of the motor electrical protections shall be conducted with this selected value.

The windings are equipped with thermal probes and anti-condensation heaters. The motors ball bearings are greased for life.

3.2.3 Vacuum system

The vacuum system comprises of:  A vacuum pumping unit plus one for quicker start-up of the system and for spare;  A vacuum tank;  An opened water tank;  Ancillary equipment.

The vacuum pump is sized so that the time of the main pump priming is in average 20 min and in the worst conditions will not exceed 30 min. Taking into account a pipes’ length of about 250 m with a ND 350 mm, the volume to depressurize is 31.5 m3 for a suction pipe. The rated point of each pump is thereby 298 m3/h at 33 mbar, taking into account a leakage factor of 20%.

The pump is of liquid ring type, horizontally mounted. The impeller is of stainless steel. The pumps’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V- 50 Hz voltage, insulation class F, temperature rise 80 K, degree of protection IP55, natural cooling with fan. The motor power is selected taking into account the system efficiency and a security factor of 15%.

The vacuum tank is 1.5 m high with a ND 700 mm, resulting a volume of 577 l. It is equipped with a ball non-return valve and a manual drain valve, all in ND 65 mm. The level of the tanks’ bottom is 0.2 m above the top level of the main pumps. For regulation purposes, the vacuum tank is equipped with 6 adjustable water level sensors, a vacuum gauge and an external level visualization system by transparent tube, with 2 isolating valves and a drain valve.

The opened water tank is required for the supply of the liquid ring, for the water discharge of the vacuum pump and for emptying the vacuum tank. It has a volume of 192 l and is located at a level under the vacuum tank. An overflow pipe is connected to the drainage system.

These devices of the vacuum system are interconnected with 2 non-return valves and 2 manual gate valves ND 65 mm and connected to the 3 main pumps by pipes with ND 65 mm. For separated priming of each main pump, 3 electric gate valves ND 65 mm are installed, with manual backup system.

3.2.4 Dewatering system

The dewatering system comprises of:  A dewatering pumping unit plus one for quicker start-up of the system and for spare;  Ancillary equipment.

The rated point of each pump is 10 l/s at 10 m. The pump is of centrifugal submersible type, vertically mounted. The pumps’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP68. The motor power is selected taking into account the system efficiency and a security factor of 20%.

The pumps are installed in a sump pit volume 0.5 m3, size 0.9 m x 0.9 m x 0.6 m depth, which is sized for 15 starts per hour of the motors, alternatively used for each pump. The dewatering pumps are interconnected and connected to a discharge pipe with ND 80 mm. For separated discharge of each pump, 2 non-return valves and 2 manual gate valves ND 80 mm are installed, with dismantling joints in between.

For dewatering regulations’ purposes, the sump pit is equipped with 6 adjustable water level sensors.

3.2.5 Water hammer protection system

The water hammer protection system comprises of:  A pressure vessel 7,000 l ND 1,500 mm NP 10 bars, with an initial pressure of 1.9 bars. The air volume at dynamic pressure will be 2.5 m3;  1 air valve ND 60 mm, installed at high point at the end of the branch KP1. Air Inlet: for a depression of -0.2 bar, should the Air Valve bring an air flow of 0.15 m 3/s and Air outlet: for overpressure of +0.2 bar, should the air valve discharge an air flow of 0.3 m3/s.  1 air valve ND 60 mm special anti-shock (without abrupt closure) against surge alleviation, installed at high point at the end of the branch KP2. Air Inlet: for a depression of -0.2 bar, should the Air Valve bring an air flow of 0.15 m3/s and Air outlet: for overpressure of +0.2 bar, should the air valve discharge an air flow of 0.3 m3/s;  A compressor plus one for quicker start-up of the system and for spare;  Ancillary pipes and equipment.

The rated point of each compressor is 2 m3/h at 6.5 bars. These devices are interconnected with 2 non-return valves and 2 manual gate valves ND 25 mm and connected to the pressure vessel by pipes with ND 25 mm. The compressors’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. The motor power is selected taking into account the system efficiency and a security factor of 20%.

The pressure vessel is equipped with a safety electric break-pressure valve with manual backup and a drain valve, all in ND 50 mm. The pressure vessel is equipped with a pressure gauge and for regulation purposes with 6 adjustable level sensors mounted on an external level visualization system by transparent tube and a magnetic visual float or equivalent system.

3.2.6 Pipes and fittings

The diameter of the pipes upstream the pumps is chosen to have a velocity of 1.0 - 2.0 m/s and the diameter of the pipes downstream the pumps is chosen to have a velocity of 2.0 - 3.0 m/s.

The pipes and fittings between the river and the pumping station have the following characteristics: steel NP 10 bars ND 350 mm.

The main pipes in the pumping room have the following characteristics:

 Pipes and fittings upstream the pumps are of steel NP 10 bars ND 350 mm;  Asymmetrical cones upstream the pumps have an angle of 10°;  Symmetrical cones downstream the pumps have an angle of 10°;  Pipes and fittings downstream the pumps are of steel NP 10 bars ND 250 mm.

The ancillary pipes in the pumping room have the following characteristics:  Pipes and fittings for the vacuum system are of steel NP 10 bars ND 65 mm;  Pipes and fittings for the dewatering system are of steel NP 10 bars ND 80 mm;  Pipes and fittings for the water hammer protection system are of steel NP 10 bars ND 25 mm;  Pipes and fittings to drain the discharge pipes are of steel NP 10 bars ND 50 mm.

The pipes and fittings outside the pumping station have the following characteristics:  Flushing pipes and fittings are of steel NP 10 bars ND 300 mm. This system is used to backwash the suction pipes and fish protection devices to clean them and avoid accumulation of sand and silt.

The pipes and fittings between the pumping station and the flow-meter chamber have the following characteristics:  Discharge pipes and fittings are of steel NP 10 bars ND 250 mm;  Main pipe is of steel NP 10 bars ND 400 mm;  Pipe connection from the main pipe to the pressure vessel is of steel NP 10 bars ND 300 mm.

3.2.7 Valves

The diameter of the valves is chosen according to the diameter of the corresponding pipes.

The main valves in the pumping room have the following characteristics:  2 valves upstream the pumps are of gate valve type, manually driven NP 10 bars ND 350 mm. They are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 valves downstream the pumps are of gate valve type, electrically driven with manual backup system NP 10 bars ND 250 mm. They are fitted with visual position indicator, torque limiter and digital position switches “Open” and “Close”. The valves are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 non-return valves downstream the pumps are of flapper type, NP 10 bars ND 250 mm.

The ancillary valves in the pumping room have the following characteristics:  Valves for the vacuum system: o 1 ball non-return valve NP 10 bars ND 65 mm for the vacuum tank; o 1 manual drain valve NP 10 bars ND 65 mm, for the vacuum tank; o 2 non-return valves NP 10 bars ND 65 mm, for the vacuum pumps; o 2 gate valves, manually driven NP 10 bars ND 65 mm, for the vacuum pumps; o 2 gate valves, electrically driven with manual backup system NP 10 bars ND 65 mm. They are equipped with 2 dismantling joints, self-locked with flanged sleeves;  Valves for the dewatering system: o 2 non-return valves NP 10 bars ND 80 mm; o 2 gate valves, manually driven NP 10 bars ND 80 mm;  Valves for the water hammer protection system: o 1 gate valve, manually driven NP 10 bars ND 300 mm, for the pressure vessel. It is equipped with 1 dismantling joint, self-locked with flanged sleeves; o 1 break-pressure valve, electrically driven with manual backup NP 10 bars ND 50 mm, for the pressure vessel; o 1 drain valve manually driven NP 10 bars ND 50 mm, for the pressure vessel; o 2 non-return valves NP 10 bars ND 50 mm, for the compressors; o 2 gate valves, manually driven NP 10 bars ND 25 mm, for the compressors;  2 gate valves, manually driven NP 10 bars ND 50 mm, for discharge pipes drainage.

The main valves outside the pumping station have the following characteristics:  2 flushing valves are of gate valve type, manually driven NP 10 bars ND 300 mm. They are equipped with 2 dismantling joints, self-locked with flanged sleeves;

3.2.8 Overhead travelling crane

An electrical hoist shall replace the manual hoist with a capacity of 1 ton with a capacity of 2 tons.

3.2.9 Ventilation

The capacity of the ventilation devices is calculated as all the efficiency losses of the motors are converted into heat and to limit de internal temperature elevation of 5 degrees compared with the external temperature. The efficiency losses are estimated at 7% of the required power of the motors i.e. 18 kW. The corresponding capacity of the ventilation system is 14,743 m3/h.

The total ventilation of the pumping room is divided into 2 fans. The rated point of each fan is thereby 7,371 m3/h at 1 mbar, taking into account head losses of 50 Pa for each air inlet and outlet. The fan is of window type, vertically mounted. It is equipped with an external protection grid with inclined flaps, which can be closed in winter. The fans’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55.

An air inlet is provided across from each fan on the other side of the pumping room. It is sized for a maximum air speed in the effective area of the grid of 3 m/s, what gives 0.8 m2 per air inlet, taking into account a reduction factor of 20% between gross area and effective area. It is equipped with an external protection grid with inclined flaps, which can be closed in winter.

The electrical room is equipped with a fan with duty point of 1,000 m3/h at 1 mbar. The fan is of window type, vertically mounted. It is equipped with an external protection grid with inclined flaps, which can be closed in winter. The fans’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. An air inlet of 0.1 m2 is provided. It is equipped with an external protection grid with inclined flaps.

For ventilation regulations’ purposes, the pumping room and the electrical room are equipped with analogical temperature sensors and another sensor is located outside the building.

3.3 ELECTRICAL EQUIPMENT

3.3.1 Power supply

The pumping station shall be supplied by low voltage three-phase 400 V-50 Hz. The grounding system is TN-C-S according to IEC standard. These outdoor utilities are under the responsibility of the electric supply company.

3.3.2 Power requirements

For the purpose of the power requirement calculation, the average power of the main pumps’ motors is taken into account when all the pumps are operating together. It differs from the maximum power calculated in the “Pumping units” chapter as the unitary flow is much less with all the pumps operating together than with a single one.

The main pumps motor average consumption is 141 kW when all the pumps are operating together, taking into account a rated motor efficiency at 93%. The ancillary equipment requires 48 kW, including a safety margin of 15 kW for maintenance purposes. The total power requirement of the pumping station is thereby 329 kW.

The calculated not compensated power factor of the pumping plant is around 0.85. It shall be rectified by reactive power compensation to 0.92. The detail of the active and reactive energy meters are shown on drawings.

3.3.3 Low voltage electrical switch- and control gears

The low voltage electrical switch- and control gears include power and control equipment to be clearly separated in the cabinets. They are equipped with safety features according international and national regulations and comprises of:  1 main switch- and control gear comprising o 1 incoming unit and general protection for the 400 kVA incoming power supply; o 1 feeder unit for the switch- and control gear for ancillaries; o 2 motor starter units for the main pumps with variable frequency drive; o 1 automatic reactive power compensation unit for the pumping station;  1 switch- and control gear for ancillaries;  1 pumping station control gear (control panel) for automation, monitoring and manual control;  1 switch gear for the operation in the non-irrigation period comprising: o 1 incoming and protection unit for the 40 kVA power supply; o Power distribution for lighting and sockets; o Power distribution for the anti-condensation heaters; o Motor starters for the drainage pumps;  5 remote control panels IP 65 in the pumping room, for the main pumps, the vacuum pumps, the drainage pumps and the compressors;  1 wall insulating switch for the crane, according to local safety regulation.

The switchgears for power equipment (general input and protection and motor starter) shall be combined by using a single section of busbars.

The operation in manual mode and the emergency actions for protection shall be hard-wired meaning it shall be function without using the PLC.

3.3.4 General incoming and protection switch gear

 The general incoming and protection switch gear comprises of (not limited to): o 1 main circuit breaker 630 A for the main power incoming; o 1 monitoring and protection device for input voltages and currents (voltage fluctuations, cuts and phase reversal, isolation defect, etc.);

o 1 multifunction data-logger: voltage, current, active and reactive power, power factor, frequency, peak values; o 1 general surge protection; o 1 circuit breaker 125 A for the automatic plant for reactive power compensation of 60 kVAR; o 1 circuit breaker 100 A for the switch- and control gear for ancillaries; o 1 busbar Cu 50x10 mm per phase, Icc = 11,9 kA; o 1 ground bus; o Heating, ventilation and lighting inside the switch gear, including control and protections.  The front door of the general incoming and protection switch gear includes: o 1 white LED indicating the presence of voltage from the main power incoming; o 1 red LED indicating a default from input voltages and currents; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 display of the data-logger; o 1 socket 230 V + G 16 A, 1 socket three-phase 400 V + G 32 A, 1 socket 24 V; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

3.3.5 Motor starter switch gear with Variable Frequency Drive

 The motor starter switch gear comprises of (not limited to): o 1 motor protection circuit breaker 315 A; o 1 multifunction Motor Protection Relay (MPR) to protect the motor either with use of Variable Frequency Drive (VFD) or by direct starting (by-pass of the VFD) for: - Overload; - Stator winding over-temperature; - Short Circuit; - Locked Rotor; - Too frequent start; - Unbalance/single phasing; - Phase reversal; - Under-voltage; o 1 contactor 315 A; o 1 double switch 315 A with mechanical interlock. This device enables to by-pass manually the Variable Frequency Drive in case of default and to operate the motor with direct starting with auxiliary contact to signal position to PLC;

o 1 Variable Frequency Drive (VFD) enabling to modify the motors speed from 60% et 100%; o 1 double switch 315 A with mechanical interlock. This device enables to isolate the Variable Frequency Drive when using the by-pass; o Control circuits comprises of relays and control voltage protections; o Part of the busbar Cu 50x10 mm; o Cable termination equipment; o Part of the switchgear ground bus; o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the motor starter switchboard includes: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 ammeter with a selector switch 4-position “0 – Phase 1 – Phase 2 – Phase 3”, including current transformer; o 1 green LED indicating the pump is operating; o 1 red LED indicating a default from Motor Protection Relay (MPR); o 1 red LED indicating a default from Variable Frequency Drive (VFD); o 1 yellow LED indicating that the by-pass is operating;

o 1 potentiometer for the Variable Frequency Drive (VFD); o 1 hour-meter; o 1 selector switch 3-position "Manual - 0 - Auto" for the pumps’ operating mode; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation. 3.3.6 Switch- and control gear for ancillaries

 The switch- and control gear for ancillaries comprises of (not limited to): o 1 main circuit breaker 80 A; o 2 motor starter devices comprising motor protection circuit breaker and 2 reversing contactors for the main valves’ actuators; o 2 motor starter devices comprising motor protection circuit breaker and 2 contactors for the vacuum pumps; o 2 motor starter devices comprising motor protection circuit breaker and 2 contactors for the compressors; o 2 motor starter devices comprising motor protection circuit breaker and 2 contactors for the fans in the pumping room;

o 1 thermo-magnetic motor protection circuit breaker and 1 contactor for the fan in the electrical room; o 1 circuit breaker for the command, automation and remote control switch- and control gear; o Circuit breakers for the vacuum system and water hammer protection system valves’ actuators; o Control circuits comprises of relays and control voltage protections; o 1 busbar Cu 10x4 mm per phase; o 1 ground bus o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the cabinet for ancillaries includes: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 2 green LED indicating the vacuum pumps are operating; o 2 red LED indicating a default of the vacuum pumps; o 2 hour-meters for the vacuum pumps; o 5 blinking white LED indicating the vacuum systems’ valves are opening. The LED remain stationary when the valves are fully opened; o 5 blinking white LED indicating the vacuum systems’ valves are closing. The LED remain stationary when the valves are fully closed; o 5 red LED indicating a default from vacuum systems’ valves; o 1 selector switch 3-position "Manual - 0 - Auto" for the vacuum systems’ operating mode; o 2 green LED indicating the compressors are operating; o 2 red LED indicating a default from the compressors; o 2 hour-meters for the compressors; o 1 blinking white LED indicating the water hammer protection systems’ valve is opening. The LED remain stationary when the valve is fully opened; o 1 blinking white LED indicating the water hammer protection systems’ valve is closing. The LED remain stationary when the valve is fully closed; o 1 red LED indicating a default from water hammer protection systems’ valve; o 1 selector switch 3-position "Manual - 0 - Auto" for the water hammer protection systems’ operating mode; o 2 blinking white LED indicating the main pumps’ valves are opening. The LED remain stationary when the valves are fully opened;

o 2 blinking white LED indicating the main pumps’ valves are closing. The LED remain stationary when the valves are fully closed; o 2 red LED indicating a default from the main pumps’ valves; o 2 selectors switch 3-position "Manual - 0 - Auto" for the main pumps’ valves’ operating mode; o 2 green LED indicating the fans of pumping room are operating; o 2 red LED indicating a default from the fans of pumping room; o 2 selectors switch 3-position "Manual - 0 - Auto" for the fans’ operating mode of pumping room; o 1 green LED indicating the fan of electrical room is operating; o 1 red LED indicating a default from the fan of electrical room; o 1 selector switch 3-position "Manual - 0 - Auto" for the fans’ operating mode of electrical room; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation. 3.3.7 Command, automation and remote control switch- and control gear

 The command, automation and remote control switch- and control gear comprises of (not limited to): o 1 Programmable Logic Controller (PLC) for managing the automatic operation and safeties (manual operation is not dependent of the controller). This unit has the necessary digital and analogical input and output cards as well as memory to monitor and store vital data and communication cards ensuring dialogue with the Remote Terminal Unit (RTU); o 1 Remote Terminal Unit (RTU) for SCADA purposes, with GSM telecommunication modem and antenna; o The terminal blocks for connecting all the equipment to the Programmable Logic Controller (PLC); o 1 Uninterruptible Power Supply (UPS) 50 Ah allocated to the Programmable Logic Controller (PLC), the Remote Terminal Unit (RTU) and the instrumentation; o Arresters’ modules for the measuring equipment (power and signal), for the Programmable Logic Controller (PLC) and for the Remote Terminal Unit (RTU); o Control circuits comprises of relays and control voltage protections; o 1 ground bus; o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the command, automation and remote control switch- and control gear includes: o 1 white LED indicating the presence of main voltage;

o 1 white LED indicating the presence of voltage from the Uninterruptible Power Supply (UPS); o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 Human Machine Interface (HMI) for: - Visualization of alarms; - Visualization of sensors’ states and analogical measurements; - Visualization and adjustment of control parameters: level thresholds, flow threshold, pressure thresholds, timers, etc.; o 1 numerical indicator for the measured flow; o 1 numerical indicator for the water level in the river; o 1 red LED indicating an alarm for low water level in the river; o 2 red LED indicating alarms for high and low pressure in the discharge main pipe; o 1 red LED indicating a default from the Programmable Logic Controller (PLC); o 1 red LED indicating a default from the Remote Terminal Unit (RTU); o 1 red LED indicating a default from the Uninterruptible Power Supply (UPS); o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

3.3.8 Secondary incoming and protection switch gear common with SPP-2

 The secondary incoming and protection switch gear comprises of (not limited to): o 1 main circuit breaker 63 A for the secondary power incoming; o 1 monitoring device for input voltages, currents and power, according to the requirements of the electrical supply company; o 2 circuit breaker 25 A downstream the monitoring device.

3.3.9 Lighting and sockets switch gear

 The lighting and sockets switch gear comprises of (not limited to): o 1 main switch 32 A for connection to the switch- and control gear for ancillaries. This device enable to switch manually from the secondary power supply used in winter to the main power supply used during the irrigation period; o 1 surge protection; o 2 motor starter devices comprising motor protection circuit breaker 10 A and 2 contactors for the drainage pumps; o 1 circuit breaker 6 A for the crane; o Branch circuit breakers for the different sockets and lighting groups; o Branch circuit breakers for anti-condensation resistors for the main motors and for the switch gears.

 The front door of the lighting and sockets switch gear includes: o 2 green LED indicating the drainage pumps are operating; o 2 red LED indicating a default from the drainage pumps; o 2 hour-meters for the drainage pumps; o 1 selector switch 3-position "Manual - 0 - Auto" for the drainage pumps’ operating mode. 3.3.10 Remote control panels for the main pumps

 These panels are located in front of the main pumps and comprise of: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 1 green LED indicating the pump is operating; o 1 red LED indicating a default from motor or pump (bearings temperature); o 1 red LED indicating a default from the switchgear; o 1 push-button "Start" to start the pump; o 1 push-button "Stop" to stop the pump; o 1 blinking white LED indicating the main valve is opening. The LED remain stationary when the valve is fully opened; o 1 blinking white LED indicating the main valve is closing. The LED remain stationary when the valve is fully closed; o 1 red LED indicating a default from the main valve; o 1 push-button "Open" to open the main valve; o 1 push-button "Stop" to let the main valve partially opened (for first filling of the network by manual operation); o 1 push-button "Close" to close the main valve; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

3.3.11 Remote control panel for the vacuum system

 This panel is located near the vacuum system and comprises of: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 2 green LED indicating the vacuum pumps are operating; o 2 red LED indicating a default of the vacuum pumps; o 2 push-buttons "Start" to start the pumps; o 2 push-buttons "Stop" to stop the pumps;

o 5 blinking white LED indicating the vacuum systems’ valves are opening. The LED remain stationary when the valves are fully opened; o 5 blinking white LED indicating the vacuum systems’ valves are closing. The LED remain stationary when the valves are fully closed; o 5 red LED indicating a default from vacuum systems’ valves; o 5 push-button "Open" to open the valves; o 5 push-button "Close" to close the valves; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation. 3.3.12 Remote control panel for the drainage pumps

 This panel is located near the drainage pumps and comprises: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 2 green LED indicating the drainage pumps are operating; o 2 red LED indicating a default from the drainage pumps; o 2 push-buttons "Start" to start the pumps; o 2 push-buttons "Stop" to stop the pumps; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation. 3.3.13 Remote control panel for the water hammer protection system

 This panel is located near the compressors and comprises of: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 2 green LED indicating the compressors are operating; o 2 red LED indicating a default from the compressors; o 2 push-buttons "Start" to start the compressors; o 2 push-buttons "Stop" to stop the compressors; o 1 blinking white LED indicating the water hammer protection systems’ valve is opening. The LED remain stationary when the valve is fully opened; o 1 blinking white LED indicating the water hammer protection systems’ valve is closing. The LED remain stationary when the valve is fully closed; o 1 red LED indicating a default from water hammer protection systems’ valve; o 1 push-button "Open" to open the valves; o 1 push-button "Close" to close the valves; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

3.4 AUTOMATION AND SCADA SYSTEM

3.4.1 Instrumentation and metering

 The instrumentation and metering devices at the pumping station SPP-1 have the following characteristics: o 1 level sensor transmitting analogical signal in the river, for water level measurement. The device includes sensor/transmitter and suitable transducer into 4-20 mA signal as input into the PLC. The distance between sensor and PLC shall be considered. The level for alarm transmission is as follows: 26.50 m, which corresponds to 90% of the ranked flows in the river; o 2 pressure sensor/transmitters with analogical signals installed on the discharge pipes of each pump, for pressure measurement. They deliver measurement values of the discharge pressure at each pump. These sensors/transmitters delivers 4-20 mA signal as input into the PLC; o 2 pressure gauges downstream the pumps; o 2 pressure gauges downstream the discharge gate valves; o 1 double pressure switch with digital signals installed on the discharge main pipe, for pressure detection. It shall switch if the discharge pressure is too low or too high. The pressure for alarms transmission is 1 bar above and below the extremes values of the discharge curve shown on the pump diagram: - 89 m = 8.7 bars: high pressure alarm; - 54 m = 5.3 bars: low pressure alarm; o 1 pressure sensor/transmitter with analogical signals installed on the discharge main pipe, for pressure measurement. It delivers measurement values of the discharge pressure at the pumping station outlet. The transmitter shall be installed in or near the manhole for local monitoring and shall deliver the information as 4-20 mA for the PLC; o 1 ultrasonic flow-meter with analogical signal installed in the manhole on the discharge main pipe, for water flow measurement and integration capability to count and store the data of water volumes taken from river and delivered to the network. The flow meter will be of a type and model approved for use in Moldova for billing purpose. It delivers measurement values of the discharge flow at the pumping station. The transmitter shall be installed in or near the manhole for local monitoring and shall deliver the information as 4-20 mA for the PLC. Two indicators for flow and volumes are installed: one in the manhole and the other on the front door of the automation switch gear; o 6 conductive water level switches with digital signal installed in the drainage sump pit, for water level detection. They deliver 4 water regulation signals and alarm signals if the water level is too low or too high. The level for signal transmission is as follows: - - 2.35 m: high level alarm;

- - 2.40 m: Start pump Nr. 2; - - 2.45 m: Start pump Nr. 1; - - 2.55 m: Stop pump Nr. 2; - - 2.60 m: Stop pump Nr. 1; - - 2.75 m: low level alarm; o 6 conductive water level switches with digital signal installed in the vacuum tank, for water level detection. They deliver 4 water regulation signals and alarm signals if the water level is too low or too high. The level for signal transmission is as follows: - 1.50 m: high level alarm; - 1.21 m: Stop pump Nr. 1; - 1.06 m: Stop pump Nr. 2; - 0.60 m: Start pump Nr. 1; - 0.30 m: Start pump Nr. 2; - 0.15 m: low level alarm; o 6 conductive water level switches with digital signal installed in the pressure vessel, for water level detection. They deliver 4 water regulation signals and alarm signals if the water level is too low or too high. The level for signal transmission is as follows from the bottom (for a vessel ND 1,500 mm): - 1.06 m: high level alarm; - 1.01 m: Start compressor Nr. 2; - 0.96 m: Start compressor Nr. 1; - 0.91 m: Stop compressor Nr. 2; - 0.86 m: Stop compressor Nr. 1; - 0.81 m: low level alarm; o Temperature sensors with analogical signals, the first installed in the pumping room, the second in the electrical room and the third outside the building, for temperature measurement. They deliver measurement values in 4-20 mA to a transducer that allows converting the information of the temperature at each location.

3.4.2 Automation and Control philosophy

3.4.2.1 Operating modes  The pumping station can be operated in 3 different modes: o Local manual mode: through the remote control panels and the cabinet for ancillaries. This level of control is widespread. The control is performed by switches in general 3-positions "Manual - 0 - Auto", push buttons "Start" - "Stop" or "Open" - "Close" for equipment controlled by the PLC. The hard wire basic safety devices are active for this mode (protections of the motor protection relay, temperatures in the motor windings or pump bearings, starting frequency, etc.);

o Local automatic mode: command through the PLC Human Machine Interface (HMI). The pumping station can run fully automatically. This level enable to have an overview of the status of the equipment, of alarms, to visualize measured values; o Remote control mode: no commands through the remote control centre are foreseen. The dispatching centre will have only monitoring and data processing and storage functions. Data will be displayed on a screen of the supervision computer. At this level will also be performed the functions of alarm management, editing, archiving, diagnostic and maintenance support.

3.4.2.2 Control philosophy The regulation of the pumping station is made according to the water flow and the pressure required by the irrigation devices. The flow/pressure equation of the network resulting from the hydraulic simulation is: H=0.00026xQ²-0.0031xQ+67.2 when the water level in the river is at its low level (26.50 m corresponding to Min. water elevation H90%). The number of operating pumps and the frequency drive of the motor will be determined to follow this network curve, minus the actual level measured by the level sensor in the river. For instance, if the water level is 1 m higher than the low level (27.50 m), the flow/pressure equation will be H=0.00026xQ²-0.0031xQ+67.2 -1=0.00026xQ²-0.0031xQ+66.2. The determination of the flow/pressure equation according to the river level shall be made once a day when the pumping station is started or at 8:00 if it was not stopped the day before. The system is designed to supply water between 20% and 100% of the rated flow. The pumping station shall be stopped if the measured flow goes under 20%. The adjustable parameter below shall be adjusted at the HMI of the PLC. The status change of the different sensors must remain during 5 s (adjustable temporization for each sensor) before the PLC undertakes an action. The instruction for manual starting of pumping station operation is as follows:  Check that all relevant equipment (water hammer system, vacuum pump system, pumps, valves, electrical supply, instrumentation and control, etc. ) is available;  Assure that the selector switches of the pumps and the vacuum system is in manual mode and of the other equipment is in automatic mode;  Assure that the discharge valve is closed;  Check that the water level measurement in the river is not triggered with alarm signal for low level;  Switch the vacuum system into automatic mode to depressurize all the suction pipes : the vacuum pumps are operating until the beginning of the regulation phase (1st stop of all vacuum pumps indicating that the water raised the upper part of the vacuum tank);

 Fill the main delivery pipe with water by starting one pump in manual mode (if it is not already filled). Some of the most distant hydrants have to be open. The gate valve downstream the operating pump has to be open at 25% to maintain a counter-pressure (monitored at the gauge) to create a head loss and enable a smooth filling;  Open a minimum of 20% of the hydrants;  Open completely the gate valve downstream the operating pump;  Switch the pump to automatic mode. The VFD shall automatically adjust its frequency to reach the set point corresponding to the flow after checking that the double pressure switch on the main delivery pipe indicates that the pipe is full of water;  The water hammer system starts in automatic mode: the compressors are operating until the beginning of the regulation phase (1st stop of all compressors indicating that the air raised the lower part of the pressure vessel);  The regulation phase of the pumps begins. The particular automatic control philosophy for the vacuum system is as follows: o Assure that the selector switch of the vacuum system is in automatic mode; o Check that the water level switch in the vacuum tank is not triggered with alarm signal for high water level; o Select the vacuum pump Nr. to operate according to the last pump which was in operation: the other pump is selected; o Start the vacuum pump; o Wait until the water level switch to stop the pump is triggered. If it is not triggered after 30 min (adjustable parameter), start the second vacuum pump. Stop the second vacuum pump when the corresponding water level switch is triggered; o Regulate the stop and start of the first vacuum pump according to the activation of the corresponding water level switches; o When the pump planned is not available (in "Manual" or "0" position or in default) the other available pump shall start. The particular automatic control philosophy for the water hammer system is as follows: o Assure that the selector switch of the water hammer system is in automatic mode; o Check that the water level switch in the pressure vessel is not triggered with alarm signal for low water level; o Select the compressor Nr. to operate according to the last compressor which was in operation: the other compressor is selected; o Start the compressor; o Wait until the water level switch to stop the compressor is triggered in the pressure vessel. If it is not triggered after 30 min (adjustable parameter), start the second compressor;

o Regulate the stop and start of the compressor according to the activation of the corresponding water level switches in the pressure vessel; o When the compressor planned is not available (in "Manual" or "0" position or in default) the other available compressor shall start. The particular automatic control philosophy of starting a pump in automatic mode is as follows: o Assure that the selector switch of the pump is in automatic mode; o Alternate the pump to start according to the last pump which was in operation: the other pump is selected; o Check that the positions’ switch of the gate valve downstream the pump is triggered on the "Close" position. If it is not triggered, launch a "close" order of the valve and wait until the positions’ switch is triggered on the "Close" position; o Close the valve of the vacuum pipe for priming the pump; o Start the pump at minimum speed (i.e. 60% of the rated frequency) and increase the speed gradually; o Increase the speed until the discharge pressure sensor of the pump delivers a measured value equal to the minimum pressure according to the equation of the network curve (64 m = 6.2 bars, adjustable parameter); o Open the gate valve downstream the pump and wait until the positions’ switch is triggered on the "Open" position; o Another pump cannot be started before the end of this sequence; o Begin the regulation phase: - According to the water flow measured by the flow-meter, accelerates or decelerates the frequency controlled drive to reach the pressure of the set point calculated with the flow/pressure equation. This pressure is measured by the pressure sensor of the discharge main pipe. The set point is calculated every 30 s (adjustable parameter) and implemented with the Proportional/Integral/Derivative function of the PLC (PID controller); - If the required pressure cannot be reached after 30 s (adjustable parameter) at the maximum frequency reduce the speed of the pump to the minimum frequency (i.e. 60% of the rated frequency) and start the other pump at the minimum frequency; - According to the water flow measured by the flow-meter, accelerates or decelerates the frequency drive of both pumps at the same speed to reach the pressure of the set point calculated with the flow/pressure equation; - If the required water flow is reduced to 125 l/s (adjustable parameter), the first running pump will be stopped and the other shall be set to its maximum speed before decelerating to meet the pressure of the set point; o Check each 60 s (adjustable parameter) that the double pressure switch installed on the discharge main pipe is not out of the limits (see the chapter "Instrumentation and metering");

o A cool down time set for 10 min (adjustable parameter) will be used to ensure that the pump cools down after each stop prior to automatic restart based on the flow in the network. This can be by-passed by the operator if required by using the push-button "Default reset" on the motor starter switchboard; o When the pump planned is not available (in "Manual" or "0" position or in default) another available pump shall start. o If the VFD is out of order, it can be manually by-passed using the double switches provided for this purpose. When the pump station will be switched in the automatic mode again a pump with VFD will be first selected and the following regulation phase will be implemented: - According to the water flow measured by the flow-meter, accelerates or decelerates the frequency drive to reach the pressure of the set point calculated with the flow/pressure equation. This pressure is measured by the pressure sensor of the discharge main pipe. The set point is calculated every 30 s (adjustable parameter) and implemented with the Proportional/Integral/ Derivative function of the VFD (PID controller); - If the required pressure cannot be reached after 30 s (adjustable parameter) at the maximum frequency start the other pump; - Reduce the speed of the former pump to the minimum frequency (i.e. 60% of the rated frequency); - According to the water flow measured by the flow-meter, accelerates or decelerates the frequency drive of the pump to reach the pressure of the set point calculated with the flow/pressure equation; - If the required water flow is reduced to 125 l/s (adjustable parameter)), the running pump with fixed speed will be stopped;  The sequence of stopping a pump is as follows: o Stop the pump; o Close the gate valve downstream the pump and wait until the positions’ switch is triggered on the "Closed" position; o Open the valve of the vacuum pipe for priming the pump. The automatic particular control philosophy for the drainage system is as follows: o Assure that the selector switch of the drainage system is in automatic mode; o Check that the water level switch in the drainage sump pit is not triggered with alarm signal for low water level; o Select the pump Nr. to operate according to the last pump which was in operation: the other pump is selected; o Start the drainage pump when the corresponding water level switch is triggered; o Start the second drainage pump when the corresponding water level switch is triggered; o Regulate the stop and start of the 2 drainage pumps according to the activation of the corresponding water level switches;

o When the pump planned is not available (in "Manual" or "0" position or in default) the other available pump shall start. The automatic particular control philosophy for the ventilation system is as follows: o Assure that the selector switch of the fan is in automatic mode; o A fan is dedicated to 1 or 2 pumps; o Start a fan when the following conditions are reached together: - One of the corresponding pumps is operating; - The temperature sensor in the pumping room indicates more than 25°C (adjustable parameter); - The temperature sensor in the pumping room indicates more than the temperature sensor outside the building; o When the fan planned is not available (in "Manual" or "0" position or in default) another available fan shall start;  Stop a fan when one of the following conditions is reached: o All the corresponding pumps are stopped; o The temperature sensor in the pumping room indicates less than 20°C (adjustable parameter); o The temperature sensor in the pumping room indicates less than the temperature sensor outside the building. 3.4.2.3 Processing failure and alarms

o In case of processed values out of their normal range, an alarm will be sent to the SCADA system: low level in the river, flood in pumping room, high and low pressure in the main discharge pipe. The pumps will not start or will be stopped with a 30 s delay between each (adjustable parameter);

o In case of flow meter failure an alarm will be sent to the SCADA system and the pumps will be stopped with a 30 s delay between each (adjustable parameter). They can be used in manual mode;

o In case of pressure sensor failure on the main pipe an alarm will be sent to the SCADA system and the pumps will be stopped with a 30 s delay between each (adjustable parameter). They can be used in manual mode;

o In case of high alarm in the vacuum tank, the vacuum pumps will be stopped until the water level reaches the start level of the 1st vacuum pump. In case of low alarm in the vacuum tank an alarm will be sent to the SCADA system and the system remains in operation;

o In case of low alarm in the pressure vessel, the compressors will be stopped until the water level reaches the start level of the 1st compressor. If it’s not the case after 60 s (adjustable parameter) the solenoid valve of the pressure vessel will be open until the water level reach the start level. In case of high alarm in the pressure vessel an alarm will be sent to the SCADA system and the system remains in operation;

o In case of VFD failure, the double switches can be manually switched to the direct starting position. A global defect alarm for pump will be sent to the SCADA system;

o In case of failure of pump, vacuum pump, dewatering pump and compressor, it will be stopped and the other standby similar equipment will automatically be started instead of the former one. A global defect alarm for the corresponding equipment will be sent to the SCADA system. If no standby equipment is available the pumps will be stopped with a 30 s delay between each (adjustable parameter;

o In case of any failure on other device, it will be stopped as well as further actions and an alarm will be sent to the SCADA system: global defect for pump and corresponding valves, for the vacuum system, for the drainage system, for the water hammer system, for the ventilation system. The pumps will be stopped with a 30 s delay between each (adjustable parameter;

o In case of total power failure of less than 1 s (adjustable parameter), the pumping station will restart automatically. If the power failure is of more than 1 s, all the equipment shall be stopped and the pumping station has to be restart by manual action as described in the instruction for manual starting of pump operation.

3.4.2.4 Processing data and curves

 The PLC shall provide the following data and curves: o Daily water flow Q (m3/h and l/s) with a step of 1 hour (adjustable parameter); o Daily water volume (m3) with a step of 1 hour (adjustable parameter) and cumulated value; o Daily water level in the river H (m) with a step of 1 hour (adjustable parameter); o Daily discharge pressure P (bars) with a step of 1 hour (adjustable parameter); o Daily hydraulic power consumption (kWh) = 9.81 x Q x P with a step of 1 hour (adjustable parameter) and cumulated value; o Daily electrical power consumption (kWh) = √3 x U x I x cos φ, with φ = arctan (reactive power/active power) with a step of 1 hour (adjustable parameter) and cumulated value; o Daily system efficiency (hydraulic power/electrical power) with a step of 1 hour (adjustable parameter) and cumulated value; o Daily electrical power consumption / water volume (kWh/m3) with a step of 1 hour (adjustable parameter) and cumulated value;

o Monthly water flow (m3/h and l/s) with a step of 1 day; o Monthly water volume (m3) with a step of 1 day and cumulated value; o Monthly water level in the river H (m) with a step of 1 day; o Monthly discharge pressure data (bars) with a step of 1 day; o Monthly hydraulic power consumption (kWh) = 9.81 x Q x H with a step of 1 day and cumulated value; o Monthly electrical power consumption (kWh) = √3 x U x I x cos φ, with φ = arctan (reactive power/active power) with a step of 1 day and cumulated value; o Monthly system efficiency (hydraulic power/electrical power) with a step of 1 day and cumulated value; o Monthly electrical power consumption / water volume (kWh/m3) with a step of 1 day and cumulated value. o Annual water flow (m3/h and l/s) with a step of 1 month; o Annual water volume (m3) with a step of 1 month and cumulated value; o Annual water level in the river H (m) with a step of 1 month; o Annual discharge pressure data (bars) with a step of 1 month; o Annual hydraulic power consumption (kWh) = 9.81 x Q x H with a step of 1 month and cumulated value; o Annual electrical power consumption (kWh) = √3 x U x I x cos φ, with φ = arctan (reactive power/active power) with a step of 1 month and cumulated value; o Annual system efficiency (hydraulic power/electrical power) with a step of 1 month and cumulated value; o Annual electrical power consumption / water volume (kWh/m3) with a step of 1 month and cumulated value.

3.4.3 PLC input /output

The PLC input / output comprises of (not limited to): DIG ANA ANA. DIG. Designation . . I O I O General incoming and protection switch gear 4 5 0 2 Presence of voltage from the main power 1 1 Circuit breaker opening from the main power 1 Default from input voltages and currents 1 1 Data-logger: voltage, current, active and reactive power 4 Default reset 1 Emergency stop 1

DIG ANA ANA. DIG. Designation . . I O I O Automatic plant for reactive power compensation 0 1 0 1 Default from automatic plant for reactive power compensation 1 1

Secondary input and protection switch gear 0 3 0 2 Presence of voltage from the secondary power 1 1 Circuit breaker opening from the secondary power 1 Default from input voltages and currents 1 1

Motor starter switch gear VFD (x2) 6 16 4 12 Presence of voltage 1 1 Default reset 1 Default VFD 1 Setpoint VFD (automatic) 1 Setpoint VFD (manual) 1 Returned information from VFD 1 Order start pump 1 Order stop pump 1 Pump is operating 1 1 Default Motor Protection Relay 1 Bearing temperature 1 Stator winding temperature 1 Position of by-pass of the VFD 1 1 Selector switch position "Auto" for the pumps operating 1 Selector switch position "Manu" for the pumps operating 1 Emergency stop 1

Switch- and control gear for ancillaries 0 59 0 71 Presence of voltage 1 1 Default reset 1 Order start compressor n°1-2 2 Order stop compressor n°1-2 2 compressor n°1-2 is operating 2 2 Default compressor n°1-2 2 2 Order open water hammer system valve 1 Water hammer system valve is opened 1 1 Order close water hammer system valve 1 Water hammer system valve is closed 1 1 Default water hammer system valve 1 1 Selector switch position "Auto" for the compressor n°1-2 2 operating Selector switch position "Manu" for the compressor n°1-2 2

DIG ANA ANA. DIG. Designation . . I O I O operating Order start vacuum pump n°1-2 2 Order stop vacuum pump n°1-2 2 Vacuum pump n°1-2 is operating 2 2 Default vacuum pump n°1-2 2 2 Order open vacuum system valve n°1-5 5 Vacuum system valve n°1-5 is opened 5 5 Order close vacuum system valve n°1-5 5 Vacuum system valve n°1-5 is closed 5 5 Default vacuum system valve n°1-5 5 5 Selector switch position "Auto" for the vacuum pump n°1-2 2 operating Selector switch position "Manu" for the vacuum pump n°1-2 2 operating Order open main valve n°1-2 2 Main valve n°1-2 is opened 2 2 Main valve n°1-2 overtorque at opening 2 Order close main valve n°1-2 2 Main valve n°1-2 is closed 2 2 Main valve n°1-2 overtorque at closing 2 Order stop main valve n°1-2 2 Default main valve n°1-2 2 2 Order start Fan n°1-2 2 Fan n°1-2 is operating 2 2 Order stop Fan n°1-2 2 Order start fan electrical room 1 Order stop fan electrical room 1 Fan electrical room is operating 1 1 Default fan n°1-2 2 2 Default fan electrical room 1 1 Selector switch position "Auto" for the fan n°1-2 operating 2 Selector switch position "Manu" for the fan n°1-2 operating 2 Selector switch position "Auto" for the fan electrical room 1 operating Selector switch position "Manu" for the fan electrical room 1 operating Emergency stop 1

Command, Automation and remote control switch- and 8 26 0 9 control gear Presence of voltage 1 1

DIG ANA ANA. DIG. Designation . . I O I O Default reset 1 Presence of voltage from Uninterruptible Power Supply 1 1 Default Uninterruptible Power Supply 1 1 Default from the Programmable Logic Controller 1 Default from the Remote Terminal Unit 1 1 Measurement of flow-meter 1 Measurement of water level in the river 1 Alarm low water level in the river 1 Pressure in the main pipe 1 Pressure in the discharge pipe pump n°1-2 2 Low pressure in the discharge main pipe 1 High pressure in the discharge main pipe 1 Alarm low pressure in the discharge main pipe 1 Alarm high pressure in the discharge main pipe 1 Water level in the drainage sump pit 6 Alarm high water level in the drainage sump pit 1 Water level in the vacuum tank 6 Water level in the pressure vessel 6 Temperature in the pumping room 1 Temperature in the electrical room 1 Temperature outside the building 1 Emergency stop 1

Lighting and sockets switch gear 0 24 0 24 Order start drainage pump n°1-2 2 Order stop drainage pump n°1-2 2 Drainage pump n°1-2 is operating 2 2 Default drainage pump n°1-2 2 2 Selector switch position "Auto" for the drainage pump n°1-2 2 operating Selector switch position "Manu" for the drainage pump n°1-2 2 operating

Local control panels for the main pumps (x2) 0 12 0 12 Signalling presence of voltage 1 Signalling pump is operating 1 Signalling default Motor Protection Relay 1 Push-button "Start" to start the pump 1 Push-button "Stop" to stop the pump 1 Signalling main valve is opened 1 Signalling main valve is closed 1

DIG ANA ANA. DIG. Designation . . I O I O Signalling default main valve 1 Push-button "Open" to open the main valve 1 Push-button "Stop" to stop the main valve 1 Push-button "Close" to close the main valve 1 Emergency stop 1

Local control panel for the vacuum system 0 15 0 20 Signalling presence of voltage 1 Signalling vacuum pump n°1-2 is operating 2 Signalling default vacuum pump n°1-2 2 Push-button "Start" to start the vacuum pump n°1-2 2 Push-button "Stop" to stop the vacuum pump n°1-2 2 Signalling vacuum system valve n°1-5 is opened 5 Signalling vacuum system valve n°1-5 is closed 5 Signalling default vacuum system valve n°1-5 5 Push-button "Open" to open the vacuum system valve n°1-5 5 Push-button "Close" to close the vacuum system valve n°1-5 5 Emergency stop 1

Local control panel for the drainage pumps 0 5 0 5 Signalling presence of voltage 1 Signalling drainage pump n°1-2 is operating 2 Signalling default drainage pump n°1-2 2 Push-button "Start" to start the drainage pump n°1-2 2 Push-button "Stop" to stop the drainage pump n°1-2 2 Emergency stop 1

Local control panel for the water hammer protection 0 7 0 8 system Signalling presence of voltage 1 Signalling compressor n°1-2 is operating 2 Signalling default compressor n°1-2 2 Push-button "Start" to start the compressor n°1-2 2 Push-button "Stop" to stop the compressor n°1-2 2 Signalling water hammer protection system valve is opened 1 Signalling water hammer protection system valve is closed 1 Signalling default water hammer protection system valve 1 Push-button "Open" to open the water hammer system valve 1 Push-button "Close" to close the water hammer system valve 1 Emergency stop 1

DIG ANA ANA. DIG. Designation . . I O I O Analog Inputs : 18 Digital Inputs : 173 Analog Outputs : 4 Digital Outputs : 166

3.4.4 Supervisory Control And Data Acquisition system (SCADA)

3.4.4.1 Structure of the system  The SCADA system is essentially defined by: o The instrumentation, metering devices and sensors in some equipment (see the chapters above), which determines information to be transmitted; o The PLC in each pumping station; o The number and distribution of the Remote Terminal Units (RTU): - At the SPP-1 pumping station; - At the SPP-2 pumping station; - At the SP-1 pumping station; - At the SP-2 pumping station;  The transmission media: GSM data – GPRS;  The supervisory station at the remote control centre (1 for Jora de Jos irrigation scheme) equipped with: o A frontal communication device for remote transmission of the various Remote Terminal Units: - Query of the different RTU; - Decoding the information; - Information storage buffer before transmission to the supervisory computer; - Serial link with the supervisory computer following an adapted protocol; - Remote transmission of various Remote Terminal Units; o A supervisory computer with a software for piloting of all associated Remote Terminal Units, displaying synoptic screens, managing the data and to emit alarms: - Piloting of all associated RTU; - Synoptic display screen; - Data management (statistical treatments); - Defect management (statistical treatments); - Operating assistance (edition of logbooks); - Management of the graphics printer; o A printer for edition of logbooks; o An on-call terminal to alert operators in case of alarm, generating automatically an SMS using the wording of the defect; o An Uninterruptible Power Supply (UPS) 50 Ah.

3.4.4.2 Remote Terminal Units  This unit handles all remote transmissions with the Supervisory Station at the control centre. It receives information directly from the PLC.

 The Remote Terminal Units provide the following main functions: o Acquisition, filtering, timing information to their appearance or status change; o Storage buffer before remote transmission; o Coding and addressing information in accordance with the protocol for remote transmission.  These facilities are equipped with a self-diagnosis system type "watchdog".  Each RTU will be equipped with modems for GSM data - GPRS communication, which is used as interface between the communication network and the Remote Terminal Unit.

3.4.4.3 Remote controlled parameters  The following information will be exchanged through the SCADA system by status change: o Power failure in the pumping station: main circuit breaker opening, lack of tension, phase inversion, etc.); o Operational status of the command: "Manual - 0 - Auto"; o Operational status of each pump "On" - "Off"; o Global defect for each pump: thermal load and max current, frequent starts, temperature probes, etc.); o Global defect for the vacuum system; o Global defect for the drainage system; o Global defect for the water hammer system; o Global defect for the ventilation system; o Water flows and volumes (once a day); o Water level alarms: - Low level in the river; - Flood in pumping room; o Water level in the river (once a day); o Pressure alarms: high and low pressure in the main discharge pipe; o PLC failure; o RTU failure; o UPS failure.

4. DETAILED ELECTROMECHANICAL AND ELECTRICAL WORKS FOR PUMPING STATION SPP-2

4.1 INTRODUCTION

4.1.1 General description of the SPP-2 pumping station

The pump station is located on the right bank of the Nistru River, downstream from Jora de Jos village on the same platform with the pump station SPP-1, presented above. The pump station is a lifting pump station only and is used to supply the pressure pump station SP-1. The total rated flow is 890 l/s at 49 m. The facilities consist of the main following equipment:  Upstream the pumping station: o Water intakes in the river; o The connecting pipes between the intakes and the pumping station;  In the pumping station: o The pumping units; o The pipes and fittings; o The valves: suction gate valves, discharge gate valves, non return valves, flushing gate valves; o Ancillaries: vacuum pumps, dewatering pumps, compressors, handling devices, ventilation, heating, etc.; o Low voltage electrical switch gears; o Instrumentation and metering devices;  Downstream the pumping station: o The connecting pipes between the pumping station and a flow-meter chamber; o The flow-meter chamber.

The command, the number of pumps needed and their speed are determined according to the water flow measured by a flow meter installed in a chamber downstream the pumping station. The pumps will automatically shut down above a maximum pressure and below a minimum pressure in the network and below the minimum water level in the river.

4.1.3 Scope of Work

The main hydro- and electro-mechanical works comprise of:  Dismantling of existing water intakes with fish protection devices in the river;  Installation of a new water intakes with fish protection devices in the river;  Dismantling of 3 existing pumping units;  Installation of 3 new pumping units;  Dismantling of the existing vacuum system;  Installation of a new vacuum system, including 2 vacuum pumping units, a water tank, pipes and valves;  Installation of a new dewatering system, including 2 dewatering pumping units, pipes and valves;  Installation of a water hammer protection system, including 2 compressors, a pressure vessel, pipes and valves;  Dismantling of existing pipes and fittings between the fish protection device and the river bank, at the pumping station inlet, in the pumping room and between the pumping station and a flow-meter chamber outside the pumping station;  Installation of new pipes and fittings between the fish protection device and the river bank, at the pumping station inlet, in the pumping room and between the pumping station and a flow-meter chamber outside the pumping station;  Dismantling of 3 existing suction gate valves and 3 existing discharge gate valves;  Installation of 3 new suction gate valves, 3 new discharge gate valves and 2 non return valves in the pumping room;  Mechanical and electrical overhaul of the handling device and change of wearing parts;  Installation of 2 air inlets and 2 fans in the pumping room and 1 air inlet and 1 fan in the electrical room;  Installation of 3 flushing gate valves in a manhole outside the pumping station.

 Dismantling of 11 existing main low voltage electrical switch gears and ancillaries’ switch gears;  Installation of 6 new main low voltage electrical switch gears, including an automation and remote control switch gear;  Installation of the interface equipment (electricity counter and auxiliaries) to the power supply company;  Dismantling of the existing lights and sockets equipment;  Installation of a new lights and sockets equipment;  Dismantling of the existing cables and cable trays;  Installation of new cables and cable trays;  Dismantling of the existing grounding system;  Installation of a new grounding system;  Dismantling of the existing lightning protection system;  Installation of a new lightning protection system.

The works also comprise of:  Commissioning of the facilities;  Providing the Operator with O&M manual and as built drawings;  Training of the operating staff.

4.2.1 Intake structures

The Contractor shall build and install on the suction pipe heads, ecologic hydraulic fish- protection devices of umbrella type– one device per line as is indicated on the drawings. The diameter of fish protection device is calculated based on the rated flow of 390 l/s and an inlet velocity of 0.1 m/s. A structure of ND 2,800 mm is providing the water inflow through lateral sides of 0.70 m width. The suction pipe ND 500 mm enters into a metal shell of ND 1400 mm diameter and of 1000 mm height. The pipes shall be butt-welded to the metal shell.

The top elevation of the umbrella-type fish protection device is determined based on its location below the minimum water level in the river, which is equal to 26.50 m above the Baltic Sea. Taking into account the potential ice thickness and a reserve, the corresponding top elevation of the umbrella is assumed to be 25.70 m above the Baltic Sea.

The type and size of the fish-protection devices and structures is agreed with the Fishery Service, under the Ministry of Environment.

4.2.2 Pumping units

The output of the hydraulic calculation states a total flow of 890 l/s at a head of 47 m. Taking into account usual head losses in a pumping station of about 1.5 m and an additional head loss of 0.5 m for the intake device, the rated pumping head is 49 m.

The total flow of the pumping station is splited into 3 pumps. There is no stand-by pump. The rated point of the big pump is thereby 297 l/s at 49 m.

The pumps are of axial split case type, horizontally mounted, with dual flows’ radial impeller. The design pressure is not less than 10 bars. The pump velocity is not more than 1,500 rpm.

The pump casing is in gray cast iron (GG-25). The impeller is in stainless steel (austeno- ferritic / duplex steel). The pumps’ sealing type is gland packing with square cross-sectioned rope.

The pumps’ ball bearings are greased for life. They are fitted with digital thermal probes to detect unusual heating.

The mathematical equation of the network curve resulting from the hydraulic simulation is: H=0.00001xQ²-0.0003xQ+40.3 (at Min. water elevation H90%). The equation of the network min. curve is: H=0.00001xQ²-0.0003xQ+37.7 (at Max. water elevation H5%).

The Contractor shall update the pumping diagram according to the characteristics of the proposed pumps and define the corresponding technical requirements, including electrical values (motors’ power, contactors’ calibration, etc.).

The hydraulic efficiency of a pump is not less than 75% for all the range of operation, whatsoever with 1, 2 or 3 pumps simultaneously in operation. The suction capacity of the pump NPSHr shall not be above 6.1 m for all the range of operation, and particularly with a single pump in operation, at a flow around 390 l/s.

The pumps motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 80 K, degree of protection IP55, natural cooling with fan. The rated motor efficiency is according to IEC 60034-30 class high efficiency IE2. The pump constructor shall supply the motors: the proper operation of the whole pumping unit (pump + motor) is under the responsibility of the pump constructor.

The motor power is selected taking into account the system efficiency and a security factor of 10% above the restrictive functioning point. In the present case this is with a single pump in operation according to the above diagram. The calculated rated motor power is thereby 241 kW. The Contractor shall update this calculation according to the actual hydraulic efficiency of the proposed pump and offer the corresponding motor standard size. The calculation of the motor electrical protections shall be conducted with this selected value.

The windings are equipped with thermal probes and anti-condensation heaters. The motors ball bearings are greased for life.

4.2.3 Vacuum system

The vacuum system comprises of:  A vacuum pumping unit plus one for quicker start-up of the system and for spare;  A vacuum tank;  An opened water tank;  Ancillary equipment.

The vacuum pump is sized so that the time of the main pump priming is in average 20 min and in the worst conditions will not exceed 30 min. Taking into account a pipes’ length of about 250 m with a ND 500 mm, the volume to depressurize is 49 m3 for a suction pipe. The rated point of each pump is thereby 609 m3/h at 33 mbar, taking into account a leakage factor of 20%.

The pump is of liquid ring type, horizontally mounted. The impeller is of stainless steel. The pumps’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V- 50 Hz voltage, insulation class F, temperature rise 80 K, degree of protection IP55, natural cooling with fan. The motor power is selected taking into account the system efficiency and a security factor of 15%.

The vacuum tank is 1.5 m high with a ND 800 mm, resulting a volume of 754 l. It is equipped with a ball non-return valve and a manual drain valve, all in ND 100 mm. The level of the tanks’ bottom is 0.2 m above the top level of the main pumps. For regulation purposes, the vacuum tank is equipped with 6 adjustable water level sensors, a vacuum gauge and an external level visualization system by transparent tube, with 2 isolating valves and a drain valve.

The opened water tank is required for the supply of the liquid ring, for the water discharge of the vacuum pump and for emptying the vacuum tank. It has a volume of 251 l and is located at a level under the vacuum tank. An overflow pipe is connected to the drainage system.

These devices of the vacuum system are interconnected with 2 non-return valves and 2 manual gate valves ND 100 mm and connected to the 3 main pumps by pipes with ND 100 mm. For separated priming of each main pump, 3 electric gate valves ND 100 mm are installed, with manual backup system.

The pumps are installed in a sump pit volume 0.65 m3, size 1 m x 1.08 m x 0.6 m depth, which is sized for 15 starts per hour of the motors, alternatively used for each pump. The dewatering pumps are interconnected and connected to a discharge pipe with ND 80 mm. For separated discharge of each pump, 2 non-return valves and 2 manual gate valves ND 80 mm are installed, with dismantling joints in between.

The water hammer protection system comprises of:  A pressure vessel 14,000 l ND 2,100 mm NP 10 bars, with an initial pressure of 1.5 bars. The air volume at dynamic pressure will be 6.8 m3;  A compressor plus one for quicker start-up of the system and for spare;  Ancillary pipes and equipment.

The rated point of each compressor is 6 m3/h at 4.5 bars. These devices are interconnected with 2 non-return valves and 2 manual gate valves ND 25 mm and connected to the pressure vessel by pipes with ND 25 mm. The compressors’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. The motor power is selected taking into account the system efficiency and a security factor of 20%.

The pressure vessel is equipped with a safety electric break-pressure valve with manual backup and a drain valve, all in ND 50 mm. The pressure vessel is equipped with a pressure gauge and for regulation purposes with 6 adjustable level sensors mounted on an external level visualization system by transparent tube and a magnetic visual float or equivalent system.

The pipes and fittings between the river and the pumping station have the following characteristics: steel NP 10 bars ND 500 mm.

The main pipes in the pumping room have the following characteristics:  Pipes and fittings upstream the pumps are of steel NP 10 bars ND 500 mm;  Asymmetrical cones upstream the pumps have an angle of 10°;  Symmetrical cones downstream the pumps have an angle of 10°;  Pipes and fittings downstream the pumps are of steel NP 10 bars ND 400 mm;

The ancillary pipes in the pumping room have the following characteristics:  Pipes and fittings for the vacuum system are of steel NP 10 bars ND 100 mm;  Pipes and fittings for the dewatering system are of steel NP 10 bars ND 80 mm;  Pipes and fittings for the water hammer protection system are of steel NP 10 bars ND 25 mm;  Pipes and fittings to drain the discharge pipes are of steel NP 10 bars ND 50 mm.

The pipes and fittings outside the pumping station have the following characteristics:  Flushing pipes and fittings are of steel NP 10 bars ND 400 mm. This system is used to backwash the suction pipes and fish protection devices to clean them and avoid accumulation of sand and silt.

The pipes and fittings between the pumping station and the flow-meter chamber have the following characteristics:  Discharge pipes and fittings are of steel NP 10 bars ND 400 mm;  Main pipe is of steel NP 10 bars ND 800 mm;  Pipe connection from the main pipe to the pressure vessel is of steel NP 10 bars ND 400 mm.

4.2.7 Valves

The main valves in the pumping room have the following characteristics:  3 valves upstream the pumps are of gate valve type, manually driven NP 10 bars ND 500 mm. They are equipped with 3 dismantling joints, self-locked with flanged sleeves;  3 valves downstream the pumps are of gate valve type, electrically driven with manual backup system NP 10 bars ND 400 mm. They are fitted with visual position indicator, torque limiter and digital position switches “Open” and “Close”. The valves are equipped with 3 dismantling joints, self-locked with flanged sleeves;  3 non-return valves downstream the pumps are of flapper type, NP 10 bars ND 400 mm. The non-return valves are equipped with 3 dismantling joints, self- locked with flanged sleeves.

The ancillary valves in the pumping room have the following characteristics:  Valves for the vacuum system: o 1 ball non-return valve NP 10 bars ND 100 mm for the vacuum tank; o 1 manual drain valve NP 10 bars ND 100 mm, for the vacuum tank; o 2 non-return valves NP 10 bars ND 100 mm, for the vacuum pumps; o 2 gate valves, manually driven NP 10 bars ND 100 mm, for the vacuum pumps; o 3 gate valves, electrically driven with manual backup system NP 10 bars ND 100 mm. They are equipped with 3 dismantling joints, self-locked with flanged sleeves;  Valves for the dewatering system: o 2 non-return valves NP 10 bars ND 80 mm; o 2 gate valves, manually driven NP 10 bars ND 80 mm;  Valves for the water hammer protection system: o 1 gate valve, manually driven NP 10 bars ND 400 mm, for the pressure vessel. It is equipped with 1 dismantling joint, self-locked with flanged sleeves; o 1 break-pressure valve, electrically driven with manual backup NP 10 bars ND 50 mm, for the pressure vessel; o 1 drain valve manually driven NP 10 bars ND 50 mm, for the pressure vessel; o 2 non-return valves NP 10 bars ND 50 mm, for the compressors; o 2 gate valves, manually driven NP 10 bars ND 25 mm, for the compressors;  3 gate valves, manually driven NP 10 bars ND 50 mm, for discharge pipes drainage.

The main valves outside the pumping station have the following characteristics:  3 flushing valves are of gate valve type, manually driven NP 10 bars ND 400 mm. They are equipped with 2 dismantling joints, self-locked with flanged sleeves;

The overhead travelling crane with a hoist capacity of 2 tons shall be reconditioned during a mechanical and electrical overhaul in workshop. The wearing parts are to be replaced by new ones.

4.2.9 Ventilation

The capacity of the ventilation devices is calculated as all the efficiency losses of the motors are converted into heat and to limit de internal temperature elevation of 5 degrees compared with the external temperature. The efficiency losses are estimated at 7% of the required power of the motors i.e. 44 kW. The corresponding capacity of the ventilation system is 36,038 m3/h.

The total ventilation of the pumping room is divided into 3 fans. The rated point of each fan is thereby 12,013 m3/h at 1 mbar, taking into account head losses of 50 Pa for each air inlet and outlet. The fan is of window type, vertically mounted. It is equipped with an external protection grid with inclined flaps, which can be closed in winter. The fans’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55.

An air inlet is provided across from each fan on the other side of the pumping room. It is sized for a maximum air speed in the effective area of the grid of 3 m/s, what gives 1.6 m2 per air inlet, taking into account a reduction factor of 20% between gross area and effective area. It is equipped with an external protection grid with inclined flaps, which can be closed in winter.

4.3.1 Power supply

The pumping station shall be supplied by low voltage three-phase 400 V-50 Hz. The grounding system is TN-C-S according to IEC standard. These outdoor utilities are under the responsibility of the electric supply company.

For the purpose of the power requirement calculation, the average power of the main pumps’ motors is taken into account when all the pumps are operating together. It differs from the maximum power calculated in the “Pumping units” chapter as the unitary flow is much less with all the pumps operating together than with a single one.

The main pumps motor average consumption is 225 kW when all the pumps are operating together, taking into account a rated motor efficiency at 93%. The ancillary equipment requires 65 kW, including a safety margin of 15 kW for maintenance purposes. The total power requirement of the pumping station is thereby 740 kW.

The calculated not compensated power factor of the pumping plant is around 0.85. It shall be rectified by reactive power compensation to 0.92.

The detail of the active and reactive energy meters are shown on drawings.

The low voltage electrical switch- and control gears include power and control equipment to be clearly separated in the cabinets. They are equipped with safety features according international and national regulations and comprises of:  1 main switch- and controlgear comprising o 1 incoming unit and general protection for the 1.000 kVA incoming power supply; o 1 feeder unit for the switch- and control gear for ancillaries; o 3 motor starter units for the main pumps with soft starters; o 1 automatic reactive power compensation unit for the pumping station;  1 switch- and control gear for ancillaries;  1 pumping station control gear (control panel) for automation, monitoring and manual control;  1 switch gear for the operation in the non-irrigation period comprising: o 1 incoming and protection unit for the 63 kVA power supply;

o Power distribution for lighting and sockets; o Power distribution for the anti-condensation heaters; o Motor starters for the drainage pumps;  6 remote control panels IP 65 in the pumping room, for the main pumps, the vacuum pumps, the drainage pumps and the compressors;  1 wall insulating switch for the crane, according to local safety regulation.

 The general incoming and protection switch gear comprises of (not limited to): o 1 main circuit breaker 1600 A for the main power incoming; o 1 monitoring and protection device for input voltages and currents (voltage fluctuations, cuts and phase reversal, isolation defect, etc.); o 1 multifunction data-logger: voltage, current, active and reactive power, power factor, frequency, peak values; o 1 general surge protection; o 1 circuit breaker 315 A for the automatic plant for reactive power compensation of 140 kVAR; o 1 circuit breaker 125 A for the switch- and control gear for ancillaries; o 1 busbar Cu 100x10 mm per phase, Icc = 22,0 kA; o 1 ground bus; o Heating, ventilation and lighting inside the switch gear, including control and protections.  The front door of the general incoming and protection switch gear includes: o 1 white LED indicating the presence of voltage from the main power incoming; o 1 red LED indicating a default from input voltages and currents; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 display of the data-logger; o 1 socket 230 V + G 16 A, 1 socket three-phase 400 V + G 32 A, 1 socket 24 V; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

4.3.5 Motor starter switch gear

 The motor starter switch gear comprises of (not limited to): o 1 motor protection circuit breaker 500 A; o 1 multifunction Motor Protection Relay (MPR) to protect the motor either with use of Soft Starter (SS) or by direct starting (by-pass of the SS) for: - Overload; - Stator winding over-temperature; - Short Circuit; - Locked Rotor; - Too frequent start; - Unbalance/single phasing; - Phase reversal; - Under-voltage; o 1 contactor 500 A; o 1 double switch 500 A with mechanical interlock. This device enables to by-pass manually the Soft Starter in case of default and to operate the motor with direct starting with auxiliary contact to signal position to PLC; o 1 Soft Starter (SS) enabling smooth starting and deceleration of the motors; o 1 double switch 500 A with mechanical interlock. This device enables to isolate the Soft Starter when using the by-pass; o Control circuits comprises of relays and control voltage protections; o Part of the busbar Cu 100x10 mm; o Cable termination equipment; o Part of the switchgear ground bus; o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the motor starter switchboard includes: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 ammeter with a selector switch 4-position “0 – Phase 1 – Phase 2 – Phase 3”, including current transformer; o 1 green LED indicating the pump is operating; o 1 red LED indicating a default from Motor Protection Relay (MPR); o 1 red LED indicating a default from Soft Starter (SS); o 1 yellow LED indicating that the by-pass is operating; o 1 hour-meter; o 1 selector switch 3-position "Manual - 0 - Auto" for the pumps’ operating mode;

o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

4.3.6 Switch- and control gear for ancillaries

 The switch- and control gear for ancillaries comprises of (not limited to): o 1 main circuit breaker 100 A; o 3 motor starter devices comprising motor protection circuit breaker and 3 reversing contactors for the main valves’ actuators; o 2 motor starter devices comprising motor protection circuit breaker and 2 contactors for the vacuum pumps; o 2 motor starter devices comprising motor protection circuit breaker and 2 contactors for the compressors; o 3 motor starter devices comprising motor protection circuit breaker and 3 contactors for the fans in the pumping room; o 1 thermo-magnetic motor protection circuit breaker and 1 contactor for the fan in the electrical room; o 1 circuit breaker for the command, automation and remote control switch- and control gear; o Circuit breakers for the vacuum system and water hammer protection system valves’ actuators; o Control circuits comprises of relays and control voltage protections; o 1 busbar Cu 10x4 mm per phase; o 1 ground bus o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the cabinet for ancillaries includes: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 2 green LED indicating the vacuum pumps are operating; o 2 red LED indicating a default of the vacuum pumps; o 2 hour-meters for the vacuum pumps; o 5 blinking white LED indicating the vacuum systems’ valves are opening. The LED remain stationary when the valves are fully opened; o 5 blinking white LED indicating the vacuum systems’ valves are closing. The LED remain stationary when the valves are fully closed; o 5 red LED indicating a default from vacuum systems’ valves;

o 1 selector switch 3-position "Manual - 0 - Auto" for the vacuum systems’ operating mode; o 2 green LED indicating the compressors are operating;

o 2 red LED indicating a default from the compressors; o 2 hour-meters for the compressors; o 1 blinking white LED indicating the water hammer protection systems’ valve is opening. The LED remain stationary when the valve is fully opened; o 1 blinking white LED indicating the water hammer protection systems’ valve is closing. The LED remain stationary when the valve is fully closed; o 1 red LED indicating a default from water hammer protection systems’ valve; o 1 selector switch 3-position "Manual - 0 - Auto" for the water hammer protection systems’ operating mode; o 3 blinking white LED indicating the main pumps’ valves are opening. The LED remain stationary when the valves are fully opened; o 3 blinking white LED indicating the main pumps’ valves are closing. The LED remain stationary when the valves are fully closed; o 3 red LED indicating a default from the main pumps’ valves; o 3 selectors switch 3-position "Manual - 0 - Auto" for the main pumps’ valves’ operating mode; o 3 green LED indicating the fans of pumping room are operating; o 3 red LED indicating a default from the fans of pumping room; o 3 selectors switch 3-position "Manual - 0 - Auto" for the fans’ operating mode of pumping room; o 1 green LED indicating the fan of electrical room is operating; o 1 red LED indicating a default from the fan of electrical room; o 1 selector switch 3-position "Manual - 0 - Auto" for the fans’ operating mode of electrical room; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

4.3.7 Command, automation and remote control switch- and control gear

 The command, automation and remote control switch- and control gear comprises of (not limited to): o 1 Programmable Logic Controller (PLC) for managing the automatic operation and safeties (manual operation is not dependent of the controller). This unit has the necessary digital and analogical input and output cards as well as memory to monitor and store vital data and communication cards ensuring dialogue with the Remote Terminal Unit (RTU);

o 1 Remote Terminal Unit (RTU) for SCADA purposes, with GSM telecommunication modem and antenna; o The terminal blocks for connecting all the equipment to the Programmable Logic Controller (PLC); o 1 Uninterruptible Power Supply (UPS) 50 Ah allocated to the Programmable Logic Controller (PLC), the Remote Terminal Unit (RTU) and the instrumentation; o Arresters’ modules for the measuring equipment (power and signal), for the Programmable Logic Controller (PLC) and for the Remote Terminal Unit (RTU); o Control circuits comprises of relays and control voltage protections; o 1 ground bus; o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the command, automation and remote control switch- and control gear includes: o 1 white LED indicating the presence of main voltage; o 1 white LED indicating the presence of voltage from the Uninterruptible Power Supply (UPS); o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 Human Machine Interface (HMI) for: - Visualization of alarms; - Visualization of sensors’ states and analogical measurements; - Visualization and adjustment of control parameters: level thresholds, flow threshold, pressure thresholds, timers, etc.; o 1 numerical indicator for the measured flow; o 1 numerical indicator for the water level in the river; o 1 red LED indicating an alarm for low water level in the river; o 2 red LED indicating alarms for high and low water levels in the discharge basin; o 6 yellow LED indicating operating water levels in the discharge basin; o 3 red LED indicating alarms for high and low pressure in the discharge main pipe; o 1 red LED indicating a default from the Programmable Logic Controller (PLC); o 1 red LED indicating a default from the Remote Terminal Unit (RTU); o 1 red LED indicating a default from the Uninterruptible Power Supply (UPS); o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

4.3.8 Secondary incoming and protection switch gear common with SPP-1

 The secondary incoming and protection switch gear comprises of (not limited to):

o 1 main circuit breaker 63 A for the secondary power incoming; o 1 monitoring device for input voltages, currents and power, according to the requirements of the electrical supply company; o 2 circuit breaker 25 A downstream the monitoring device.

 The lighting and sockets switch gear comprises of (not limited to): o 1 main switch 32 A for connection to the switch- and control gear for ancillaries. This device enable to switch manually from the secondary power supply used in winter to the main power supply used during the irrigation period; o 1 surge protection; o 2 motor starter devices comprising motor protection circuit breaker 10 A and 2 contactors for the drainage pumps; o 1 circuit breaker 6 A for the crane; o Branch circuit breakers for the different sockets and lighting groups; o Branch circuit breakers for anti-condensation resistors for the main motors and for the switch gears.  The front door of the lighting and sockets switch gear includes: o 2 green LED indicating the drainage pumps are operating; o 2 red LED indicating a default from the drainage pumps; o 2 hour-meters for the drainage pumps; o 1 selector switch 3-position "Manual - 0 - Auto" for the drainage pumps’ operating mode. 4.3.10 Remote control panels for the main pumps

 These panels are located in front of the main pumps, on the footbridge and comprise of: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 1 green LED indicating the pump is operating; o 1 red LED indicating a default from motor or pump (bearings temperature); o 1 red LED indicating a default from the switchgear; o 1 push-button "Start" to start the pump; o 1 push-button "Stop" to stop the pump; o 1 blinking white LED indicating the main valve is opening. The LED remain stationary when the valve is fully opened; o 1 blinking white LED indicating the main valve is closing. The LED remain stationary when the valve is fully closed;

o 1 red LED indicating a default from the main valve; o 1 push-button "Open" to open the main valve; o 1 push-button "Stop" to let the main valve partially opened (for first filling of the network by manual operation); o 1 push-button "Close" to close the main valve; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

4.3.11 Remote control panel for the vacuum system

 This panel is located near the vacuum system and comprises of: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 2 green LED indicating the vacuum pumps are operating; o 2 red LED indicating a default of the vacuum pumps; o 2 push-buttons "Start" to start the pumps; o 2 push-buttons "Stop" to stop the pumps; o 5 blinking white LED indicating the vacuum systems’ valves are opening. The LED remain stationary when the valves are fully opened; o 5 blinking white LED indicating the vacuum systems’ valves are closing. The LED remain stationary when the valves are fully closed; o 5 red LED indicating a default from vacuum systems’ valves; o 5 push-button "Open" to open the valves; o 5 push-button "Close" to close the valves; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

4.3.12 Remote control panel for the drainage pumps

 This panel is located near the drainage pumps and comprises: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 2 green LED indicating the drainage pumps are operating; o 2 red LED indicating a default from the drainage pumps; o 2 push-buttons "Start" to start the pumps; o 2 push-buttons "Stop" to stop the pumps; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

4.3.13 Remote control panel for the water hammer protection system

 This panel is located near the compressors and comprises of: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 2 green LED indicating the compressors are operating; o 2 red LED indicating a default from the compressors; o 2 push-buttons "Start" to start the compressors; o 2 push-buttons "Stop" to stop the compressors; o 1 blinking white LED indicating the water hammer protection systems’ valve is opening. The LED remain stationary when the valve is fully opened; o 1 blinking white LED indicating the water hammer protection systems’ valve is closing. The LED remain stationary when the valve is fully closed; o 1 red LED indicating a default from water hammer protection systems’ valve; o 1 push-button "Open" to open the valves; o 1 push-button "Close" to close the valves; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

 The instrumentation and metering devices at the pumping station SPP-2 have the following characteristics: o 1 level sensor transmitting analogical signal in the river, for water level measurement. The device includes sensor/transmitter and suitable transducer into 4-20 mA signal as input into the PLC. The distance between sensor and PLC shall be considered. The level for alarm transmission is as follows: 26.50 m, which corresponds to 90% of the ranked flows in the river; o 3 pressure sensor/transmitters with analogical signals installed on the discharge pipes of each pump, for pressure measurement. They deliver measurement values of the discharge pressure at each pump. These sensors/transmitters delivers 4-20 mA signal as input into the PLC; o 3 pressure gauges downstream the pumps; o 3 pressure gauges downstream the discharge gate valves; o 1 double pressure switch with digital signals installed on the discharge main pipe, for pressure detection. It shall switch if the discharge pressure is too low or too high. The pressure for alarms transmission is 1 bar above and below the extremes values of the discharge curve shown on the pump diagram:

- 59 m = 5.8 bars: high pressure alarm; - 29 m = 2.8 bars: low pressure alarm; o 1 pressure sensor/transmitter with analogical signals installed on the discharge main pipe, for pressure measurement. It delivers measurement values of the discharge pressure at the pumping station outlet. The transmitter shall be installed in or near the manhole for local monitoring and shall deliver the information as 4-20 mA for the PLC; o 1 ultrasonic flow-meter with analogical signal installed in the manhole on the discharge main pipe, for water flow measurement and integration capability to count and store the data of water volumes taken from river and delivered to the water basin. The flow meter will be of a type and model approved for use in Moldova for billing purpose. It delivers measurement values of the discharge flow at the pumping station. The transmitter shall be installed in or near the manhole for local monitoring and shall deliver the information as 4-20 mA for the PLC. Two indicators for flow and volumes are installed: one in the manhole and the other on the front door of the automation switch gear; o 6 conductive water level switches with digital signal installed in the drainage sump pit, for water level detection. They deliver 4 water regulation signals and alarm signals if the water level is too low or too high. The level for signal transmission is as follows: - - 3.90 m: high level alarm; - - 3.95 m: Start pump Nr. 2; - - 4.00 m: Start pump Nr. 1; - - 4.05 m: Stop pump Nr. 2; - - 4.10 m: Stop pump Nr. 1; - - 4.25 m: low level alarm;

o 6 conductive water level switches with digital signal installed in the vacuum tank, for water level detection. They deliver 4 water regulation signals and alarm signals if the water level is too low or too high. The level for signal transmission is as follows: - 1.50 m: high level alarm; - 1.21 m: Stop pump Nr. 1; - 1.06 m: Stop pump Nr. 2; - 0.60 m: Start pump Nr. 1; - 0.30 m: Start pump Nr. 2; - 0.15 m: low level alarm;

o 6 conductive water level switches with digital signal installed in the pressure vessel, for water level detection. They deliver 4 water regulation signals and alarm signals if the water level is too low or too high. The level for signal transmission is as follows from the bottom (for a vessel ND 2,100 mm): - 1.18 m: high level alarm; - 1.13 m: Start compressor Nr. 2; - 1.08 m: Start compressor Nr. 1;

- 1.03 m: Stop compressor Nr. 2; - 0.98 m: Stop compressor Nr. 1; - 0.93 m: low level alarm; o temperature sensors with analogical signals, the first installed in the pumping room, the second in the electrical room and the third outside the building, for temperature measurement. They deliver measurement values in 4-20 mA to a transducer that allows converting the information of the temperature at each location.

 The instrumentation and metering devices at the discharge basin SP-1 have the following characteristics: o level sensor with analogical signal installed in the basin, for water level detection, plus 2 float switches for alarm level. The sensor delivers information in 4-20 mA to a transducer that allows converting the information. It is delivered 6 water regulation signals and 2 alarm signals if the water level is too low or too high. The level for signal transmission is as follows: - 65.3 m: high level alarm; - 65.1 m: Stop pump Nr. 1; - 65.0 m: Stop pump Nr. 2; - 64.9 m: Stop pump Nr. 3; - 64.8 m: Start pump Nr. 1; - 64.7 m: Start pump Nr. 2; - 64.6 m: Start pump Nr. 3. - 64.4 m: low level alarm.

4.4.2.1 Operating modes  The pumping station can be operated in 3 different modes: o Local manual mode: through the remote control panels and the cabinet for ancillaries. This level of control is widespread. The control is performed by switches in general 3-positions "Manual - 0 - Auto", push buttons "Start" - "Stop" or "Open" - "Close" for equipment controlled by the PLC. The hard wire basic safety devices are active for this mode (protections of the motor protection relay, temperatures in the motor windings or pump bearings, starting frequency, etc.); o Local automatic mode: command through the PLC Human Machine Interface (HMI). The pumping station can run fully automatically. This level enable to have an overview of the status of the equipment, of alarms, to visualize measured values;

o Remote control mode: no commands through the remote control centre are foreseen. The dispatching centre will have only monitoring and data processing and storage functions. Data will be displayed on a screen of the supervision computer. At this level will also be performed the functions of alarm management, editing, archiving, diagnostic and maintenance support.

4.4.2.2 Control philosophy The regulation of the pumping station is made according to the water level in the discharge basin. The number of operating pumps will be determined for each level in the basin (see the chapter "Instrumentation and metering"). It is verified that the volume of regulation between the start level and the stop level of a pump is compatible with 6 starts per hour of the motors.

The adjustable parameter below shall be adjusted at the HMI of the PLC. The status change of the different sensors must remain during 5 s (adjustable temporization for each sensor) before the PLC undertakes an action. The instruction for manual starting of pumping station operation is as follows:  Check that all relevant equipment (water hammer system, vacuum pump system, pumps, valves, electrical supply, instrumentation and control, etc. ) is available;  Assure that the selector switches of the pumps and the vacuum system is in manual mode and of the other equipment is in automatic mode;  Assure that the discharge valve is closed;  Check that the water level measurement in the river is not triggered with alarm signal for low level;  Switch the vacuum system into automatic mode to depressurize all the suction pipes : the vacuum pumps are operating until the beginning of the regulation phase (1st stop of all vacuum pumps indicating that the water raised the upper part of the vacuum tank);  Fill the main delivery pipe with water by starting one pump in manual mode (if it is not already filled). Some of the most distant hydrants have to be open. The gate valve downstream the operating pump has to be open at 25% to maintain a counter-pressure (monitored at the gauge) to create a head loss and enable a smooth filling;  Open completely the gate valve downstream the operating pump;  Switch the pump to automatic mode. The SS shall start progressively to reach the nominal point corresponding to the flow after checking that the double pressure switch on the main delivery pipe indicates that the pipe is full of water;  The water hammer system starts in automatic mode: the compressors are operating until the beginning of the regulation phase (1st stop of all compressors indicating that the air raised the lower part of the pressure vessel);  The regulation phase of the pumps begins.

The particular automatic control philosophy for the vacuum system is as follows: o Assure that the selector switch of the vacuum system is in automatic mode; o Check that the water level switch in the vacuum tank is not triggered with alarm signal for high water level; o Select the vacuum pump Nr. to operate according to the last pump which was in operation: the other pump is selected; o Start the vacuum pump; o Wait until the water level switch to stop the pump is triggered. If it is not triggered after 30 min (adjustable parameter), start the second vacuum pump. Stop the second vacuum pump when the corresponding water level switch is triggered; o Regulate the stop and start of the first vacuum pump according to the activation of the corresponding water level switches; o When the pump planned is not available (in "Manual" or "0" position or in default) the other available pump shall start.

The particular automatic control philosophy for the water hammer system is as follows: o Assure that the selector switch of the water hammer system is in automatic mode; o Check that the water level switch in the pressure vessel is not triggered with alarm signal for low water level; o Select the compressor Nr. to operate according to the last compressor which was in operation: the other compressor is selected; o Start the compressor; o Wait until the water level switch to stop the compressor is triggered in the pressure vessel. If it is not triggered after 30 min (adjustable parameter), start the second compressor; o Regulate the stop and start of the compressor according to the activation of the corresponding water level switches in the pressure vessel; o When the compressor planned is not available (in "Manual" or "0" position or in default) the other available compressor shall start.

The particular automatic control philosophy of starting a pump in automatic mode is as follows: o Assure that the selector switch of the pump is in automatic mode; o Alternate the pump to start according to the last pump which was in operation: the other pump is selected; o Check that the positions’ switch of the gate valve downstream the pump is triggered on the "Close" position. If it is not triggered, launch a "close" order of the valve and wait until the positions’ switch is triggered on the "Close" position; o Close the valve of the vacuum pipe for priming the pump; o Start the pump;

o Wait until the discharge pressure sensor of the pump delivers a measured value equal to the minimum pressure according to the equation of the network curve (41 m = 4.0 bars, adjustable parameter); o Open the gate valve downstream the pump and wait until the positions’ switch is triggered on the "Open" position; o Another pump cannot be started before the end of this sequence; o Begin the regulation phase: regulate the stop and start of the pumps according water level in the basin and the corresponding thresholds indicated in the PLC (see the chapter "Instrumentation and metering"); o Check each 60 s (adjustable parameter) that the double pressure switch installed on the discharge main pipe is not out of the limits (see the chapter "Instrumentation and metering"); o A cool down time set for 10 min (adjustable parameter) will be used to ensure that the pump cools down after each stop prior to automatic restart based on the water level in the basin. This can be by-passed by the operator if required by using the push-button "Default reset" on the motor starter switchboard; o When the pump planned is not available (in "Manual" or "0" position or in default) another available pump shall start. o If the SS is out of order, it can be manually by-passed using the double switches provided for this purpose.  The sequence of stopping a pump is as follows: o Stop the pump; o Close the gate valve downstream the pump and wait until the positions’ switch is triggered on the "Closed" position; o Open the valve of the vacuum pipe for priming the pump.

The automatic particular control philosophy for the drainage system is as follows: o Assure that the selector switch of the drainage system is in automatic mode; o Check that the water level switch in the drainage sump pit is not triggered with alarm signal for low water level; o Select the pump Nr. to operate according to the last pump which was in operation: the other pump is selected; o Start the drainage pump when the corresponding water level switch is triggered; o Start the second drainage pump when the corresponding water level switch is triggered; o Regulate the stop and start of the 2 drainage pumps according to the activation of the corresponding water level switches; o When the pump planned is not available (in "Manual" or "0" position or in default) the other available pump shall start.

The automatic particular control philosophy for the ventilation system is as follows:

o Assure that the selector switch of the fan is in automatic mode; o A fan is dedicated to 1 or 2 pumps; o Start a fan when the following conditions are reached together: - One of the corresponding pumps is operating; - The temperature sensor in the pumping room indicates more than 25°C (adjustable parameter); - The temperature sensor in the pumping room indicates more than the temperature sensor outside the building;

o When the fan planned is not available (in "Manual" or "0" position or in default) another available fan shall start;  Stop a fan when one of the following conditions is reached: o All the corresponding pumps are stopped; o The temperature sensor in the pumping room indicates less than 20°C (adjustable parameter); o The temperature sensor in the pumping room indicates less than the temperature sensor outside the building.

4.4.2.3 Processing failure and alarms  In case of processed values out of their normal range, an alarm will be sent to the SCADA system: low level in the river, flood in pumping room, high and low pressure in the main discharge pipe. The pumps will not start or will be stopped with a 30 s delay between each (adjustable parameter);  In case of flow meter failure an alarm will be sent to the SCADA system and the pumps will be stopped with a 30 s delay between each (adjustable parameter). They can be used in manual mode;  In case of pressure sensor failure on the main pipe an alarm will be sent to the SCADA system and the pumps will be stopped with a 30 s delay between each (adjustable parameter). They can be used in manual mode;  In case of high alarm in the vacuum tank, the vacuum pumps will be stopped until the water level reaches the start level of the 1st vacuum pump. In case of low alarm in the vacuum tank an alarm will be sent to the SCADA system and the system remains in operation;  In case of low alarm in the pressure vessel, the compressors will be stopped until the water level reaches the start level of the 1st compressor. If it’s not the case after 60 s (adjustable parameter) the solenoid valve of the pressure vessel will be open until the water level reach the start level. In case of high alarm in the pressure vessel an alarm will be sent to the SCADA system and the system remains in operation;  In case of SS failure, the double switches can be manually switched to the direct starting position. A global defect alarm for pump will be sent to the SCADA system;

 In case of failure of pump, vacuum pump, dewatering pump and compressor, it will be stopped and the other standby similar equipment will automatically be started instead of the former one. A global defect alarm for the corresponding equipment will be sent to the SCADA system. If no standby equipment is available the pumps will be stopped with a 30 s delay between each (adjustable parameter);  In case of any failure on other device, it will be stopped as well as further actions and an alarm will be sent to the SCADA system: global defect for pump and corresponding valves, for the vacuum system, for the drainage system, for the water hammer system, for the ventilation system. The pumps will be stopped with a 30 s delay between each (adjustable parameter);  In case of total power failure of less than 1 s (adjustable parameter), the pumping station will restart automatically. If the power failure is of more than 1 s, all the equipment shall be stopped and the pumping station has to be restart by manual action as described in the instruction for manual starting of pump operation.

4.4.2.4 Processing data and curves  The PLC shall provide the following data and curves: o Daily water flow Q (m3/h and l/s) with a step of 1 hour (adjustable parameter); o Daily water volume (m3) with a step of 1 hour (adjustable parameter) and cumulated value; o Daily water level in the river H (m) with a step of 1 hour (adjustable parameter); o Daily discharge pressure P (bars) with a step of 1 hour (adjustable parameter); o Daily hydraulic power consumption (kWh) = 9.81 x Q x P with a step of 1 hour (adjustable parameter) and cumulated value; o Daily electrical power consumption (kWh) = √3 x U x I x cos φ, with φ = arctan (reactive power/active power) with a step of 1 hour (adjustable parameter) and cumulated value; o Daily system efficiency (hydraulic power/electrical power) with a step of 1 hour (adjustable parameter) and cumulated value; o Daily electrical power consumption / water volume (kWh/m3) with a step of 1 hour (adjustable parameter) and cumulated value; o Monthly water flow (m3/h and l/s) with a step of 1 day; o Monthly water volume (m3) with a step of 1 day and cumulated value; o Monthly water level in the river H (m) with a step of 1 day; o Monthly discharge pressure data (bars) with a step of 1 day; o Monthly hydraulic power consumption (kWh) = 9.81 x Q x H with a step of 1 day and cumulated value; o Monthly electrical power consumption (kWh) = √3 x U x I x cos φ, with φ = arctan (reactive power/active power) with a step of 1 day and cumulated value;

o Monthly system efficiency (hydraulic power/electrical power) with a step of 1 day and cumulated value; o Monthly electrical power consumption / water volume (kWh/m3) with a step of 1 day and cumulated value. o Annual water flow (m3/h and l/s) with a step of 1 month; o Annual water volume (m3) with a step of 1 month and cumulated value; o Annual water level in the river H (m) with a step of 1 month; o Annual discharge pressure data (bars) with a step of 1 month; o Annual hydraulic power consumption (kWh) = 9.81 x Q x H with a step of 1 month and cumulated value; o Annual electrical power consumption (kWh) = √3 x U x I x cos φ, with φ = arctan (reactive power/active power) with a step of 1 month and cumulated value; o Annual system efficiency (hydraulic power/electrical power) with a step of 1 month and cumulated value; o Annual electrical power consumption / water volume (kWh/m3) with a step of 1 month and cumulated value.

The PLC input / output comprises of (not limited to): DIG ANA ANA. DIG. Designation . . I O I O General incoming and protection switch gear 4 5 0 2 Presence of voltage from the main power 1 1 Circuit breaker opening from the main power 1 Default from input voltages and currents 1 1 Data-logger: voltage, current, active and reactive power 4 Default reset 1 Emergency stop 1

Automatic plant for reactive power compensation 0 1 0 1 Default from automatic plant for reactive power compensation 1 1

Motor starter switch gear (x3) 6 24 0 18 Presence of voltage 1 1

DIG ANA ANA. DIG. Designation . . I O I O Default reset 1 Default soft starter 1 Order start pump 1 Order stop pump 1 Pump is operating 1 1 Default Motor Protection Relay 1 Bearing temperature 1 Stator winding temperature 1 Position of by-pass of the soft starter 1 1 Selector switch position "Auto" for the pumps operating 1 Selector switch position "Manu" for the pumps operating 1 Emergency stop 1

Switch- and control gear for ancillaries 0 68 0 82 Presence of voltage 1 1 Default reset 1 Order start compressor n°1-2 2 Order stop compressor n°1-2 2 Compressor n°1-2 is operating 2 2 Default compressor n°1-2 2 2 Order open water hammer system valve 1 Water hammer system valve is opened 1 1 Order close water hammer system valve 1 Water hammer system valve is closed 1 1 Default water hammer system valve 1 1 Selector switch position "Auto" for the compressor n°1-2 2 operating Selector switch position "Manu" for the compressor n°1-2 2 operating Order start vacuum pump n°1-2 2 Order stop vacuum pump n°1-2 2 Vacuum pump n°1-2 is operating 2 2 Default vacuum pump n°1-2 2 2 Order open vacuum system valve n°1-5 5 Vacuum system valve n°1-5 is opened 5 5 Order close vacuum system valve n°1-5 5 Vacuum system valve n°1-5 is closed 5 5 Default vacuum system valve n°1-5 5 5 Selector switch position "Auto" for the vacuum pump n°1-2 2 operating Selector switch position "Manu" for the vacuum pump n°1-2 2

DIG ANA ANA. DIG. Designation . . I O I O operating Order open main valve n°1-3 3 Main valve n°1-3 is opened 3 3 Main valve n°1-3 overtorque at opening 3 Order close main valve n°1-3 3 Main valve n°1-3 is closed 3 3 Main valve n°1-3 overtorque at closing 3 Order stop main valve n°1-3 3 Default main valve n°1-3 3 3 Order start Fan n°1-3 3 Fan n°1-3 is operating 3 3 Order stop Fan n°1-3 4 Order start fan electrical room 1 Order stop fan electrical room 1 Fan electrical room is operating 1 1 Default fan n°1-3 3 3 Default fan electrical room 1 1 Selector switch position "Auto" for the fan n°1-3 operating 3 Selector switch position "Manu" for the fan n°1-3 operating 3 Selector switch position "Auto" for the fan electrical room 1 operating Selector switch position "Manu" for the fan electrical room 1 operating Emergency stop 1

Command, Automation and remote control switch- and 9 29 0 11 control gear Presence of voltage 1 1 Default reset 1 Presence of voltage from Uninterruptible Power Supply 1 1 Default Uninterruptible Power Supply 1 1 Default from the Programmable Logic Controller 1 Default from the Remote Terminal Unit 1 1 Measurement of flow-meter 1 Measurement of water level in the river 1 Alarm low water level in the river 1 Water level in the discharge basin 1 Low water level in the discharge basin 1 High water level in the discharge basin 1 Alarm low water level in the discharge basin 1 Alarm high water level in the discharge basin 1

DIG ANA ANA. DIG. Designation . . I O I O Pressure in the discharge pipe pump n°1-3 3 Low pressure in the discharge main pipe 1 High pressure in the discharge main pipe 1 Alarm low pressure in the discharge main pipe 1 Alarm high pressure in the discharge main pipe 1 Water level in the drainage sump pit 6 Alarm high water level in the drainage sump pit 1 Water level in the vacuum tank 6 Water level in the pressure vessel 6 Temperature in the pumping room 1 Temperature in the electrical room 1 Temperature outside the building 1 Emergency stop 1

Lighting and sockets switch gear 0 24 0 24 Order start drainage pump n°1-2 2 Order stop drainage pump n°1-2 2 Drainage pump n°1-2 is operating 2 2 Default drainage pump n°1-2 2 2 Selector switch position "Auto" for the drainage pump n°1-2 2 operating Selector switch position "Manu" for the drainage pump n°1-2 2 operating

Local control panels for the main pumps (x3) 0 18 0 18 Signalling presence of voltage 1 Signalling pump is operating 1 Signalling default Motor Protection Relay 1 Push-button "Start" to start the pump 1 Push-button "Stop" to stop the pump 1 Signalling main valve is opened 1 Signalling main valve is closed 1 Signalling default main valve 1 Push-button "Open" to open the main valve 1 Push-button "Stop" to stop the main valve 1 Push-button "Close" to close the main valve 1 Emergency stop 1

Local control panel for the vacuum system 0 15 0 20 Signalling presence of voltage 1 Signalling vacuum pump n°1-2 is operating 2

DIG ANA ANA. DIG. Designation . . I O I O Signalling default vacuum pump n°1-2 2 Push-button "Start" to start the vacuum pump n°1-2 2 Push-button "Stop" to stop the vacuum pump n°1-2 2 Signalling vacuum system valve n°1-5 is opened 5 Signalling vacuum system valve n°1-5 is closed 5 Signalling default vacuum system valve n°1-5 5 Push-button "Open" to open the vacuum system valve n°1-5 5 Push-button "Close" to close the vacuum system valve n°1-5 5 Emergency stop 1

Local control panel for the water hammer protection 0 7 0 8 system Signalling presence of voltage 1 Signalling compressor n°1-2 is operating 2 Signalling default compressor n°1-2 2 Push-button "Start" to start the compressor n°1-2 2 Push-button "Stop" to stop the compressor n°1-2 2 Signalling water hammer protection system valve is opened 1 Signalling water hammer protection system valve is closed 1 Signalling default water hammer protection system valve 1 Push-button "Open" to open the water hammer system valve 1 Push-button "Close" to close the water hammer system valve 1 Emergency stop 1

Analog Inputs : 19 Digital Inputs : 199 Analog Outputs : 0 Digital Outputs : 191

4.4.4 Supervisory Control and Data Acquisition system (SCADA)

4.4.4.1 Structure of the system  The SCADA system is essentially defined by: o The instrumentation, metering devices and sensors in some equipment (see the chapters above), which determines information to be transmitted; o The PLC in each pumping station; o The number and distribution of the Remote Terminal Units (RTU): - At the SPP-1 pumping station; - At the SPP-2 pumping station; - At the SP-1 pumping station; - At the SP-2 pumping station;  The transmission media: GSM data – GPRS;  The supervisory station at the remote control center equipped with: o A frontal communication device for remote transmission of the various Remote Terminal Units: - Query of the different RTU; - Decoding the information; - Information storage buffer before transmission to the supervisory computer; - Serial link with the supervisory computer following an adapted protocol; - Remote transmission of various Remote Terminal Units; o A supervisory computer with a software for piloting of all associated Remote Terminal Units, displaying synoptic screens, managing the data and to emit alarms: - Piloting of all associated RTU; - Synoptic display screen; - Data management (statistical treatments); - Defect management (statistical treatments); - Operating assistance (edition of logbooks); - Management of the graphics printer; o A printer for edition of logbooks; o An on-call terminal to alert operators in case of alarm, generating automatically an SMS using the wording of the defect; o An Uninterruptible Power Supply (UPS) 50 Ah.

4.4.4.2 Remote Terminal Units  This unit handles all remote transmissions with the Supervisory Station at the control center. It receives information directly from the PLC.

4.4.4.3 Remote controlled parameters  The following information will be exchanged through the SCADA system by status change: o Power failure in the pumping station: main circuit breaker opening, lack of tension, phase inversion, etc.); o Operational status of the command: "Manual - 0 - Auto"; o Operational status of each pump "On" - "Off"; o Global defect for each pump: thermal load and max current, frequent starts, temperature probes, etc.); o Global defect for the vacuum system; o Global defect for the drainage system; o Global defect for the water hammer system; o Global defect for the ventilation system; o Water flows and volumes (once a day); o Water level alarms: - Low level in the river; - High level in the basin; - Flood in pumping room; o Water level in the river (once a day); o Pressure alarms: high and low pressure in the main discharge pipe; o PLC failure; o RTU failure; o UPS failure.

5. DETAILED ELECTROMECHANICAL AND ELECTRICAL WORKS FOR PUMPING STATION SP-1

5.1 INTRODUCTION

5.1.1 General description of the SP-1 pumping station

The SP-1 pumping station is located to the west of the pump station SPP2. The pump station SP-1 is a pressure pumping station supplying water to the served irrigation network and a lifting pump station supplying water to the pressure pump station SP-2. The facilities consist of the main following equipment:  Upstream the pumping station: o Water intakes in the basin; o The connecting pipes between the intakes and the pumping station;  In the pumping station: o The pumping units; o The pipes and fittings; o The valves: suction gate valves, discharge gate valves, non return valves; o Ancillaries: dewatering pumps, compressors, handling devices, ventilation, etc.; o Low and high voltage electrical switch gears; o Instrumentation and metering devices;  Downstream the pumping station: o The connecting pipes between the pumping station and a flow-meter chamber; o The flow-meter chamber.

For SP-1A and SP1-B the command, the number of pumps needed and their speed are determined according to the water flow measured by a flow meter installed in a chamber downstream the pumping station. The pumps will automatically shut down above a maximum pressure and below a minimum pressure in the network and below the minimum water level in the basin.

For SP-1C the command and the number of pumps needed are determined according to the water level detected by sensors installed in the discharge basin. The pumps will automatically shut down above a maximum water level in the discharge basin and below the minimum water level in the supply basin.

5.1.3 Scope of Work

The main hydro- and electro-mechanical works comprise of:  Dismantling of existing water intakes in the basin;  Installation of new water intakes with grid in the basin;  Dismantling of 6 existing pumping units;  Installation of 6 new pumping units;  Installation of a new dewatering system, including 2 dewatering pumping units, pipes and valves;  Installation of a water hammer protection system, including 6 compressors, 3 pressure vessels, pipes and valves;  Dismantling of existing pipes and fittings between the water intake and the pumping station inlet, in the pumping room and between the pumping station and a flow-meter chamber outside the pumping station;  Installation of new pipes and fittings between the water intake and the pumping station inlet, in the pumping room and between the pumping station and flow-meter chambers outside the pumping station;  Dismantling of 6 existing suction gate valves, 6 existing non return valves and 6 existing discharge gate valves in the pumping room;  Installation of 6 new suction gate valves, 6 non return valves in the pumping room and 6 new discharge gate valves;  Mechanical and electrical overhaul of the handling device and change of wearing parts;  Installation of 5 air inlets and 5 fans in the pumping room and 1 air inlet and 1 fan in the electrical room;

 Dismantling of 13 existing main low voltage electrical switch gears and ancillaries’ switch gears and 4 high voltage electrical switch gears;  Installation of 8 new main low voltage electrical switch gears, including an automation and remote control switch gear and 6 new main high voltage electrical switch gears;  Installation of the interface equipment (electricity counter and auxiliaries) to the power supply company;  Dismantling of the existing lights and sockets equipment;  Installation of a new lights and sockets equipment;  Dismantling of the existing cables and cable trays;  Installation of new cables and cable trays;  Dismantling of the existing grounding system;  Installation of a new grounding system;  Dismantling of the existing lightning protection system;  Installation of a new lightning protection system.

The works also comprise of:  Commissioning of the facilities;  Providing the Operator with O&M manual and as built drawings; Training of the operating staff.

5.2.1 Pumping units

5.2.1.1 Pumping units for SP-1A The output of the hydraulic calculation states a total flow of 235 l/s at 65 m. Taking into account usual head losses in a pumping station of about 1.5 m, the rated pumping head is 66.5 m. The total flow of the pumping station is split into 2 pumps. There is no stand-by pump. The rated point of each pump is thereby 118 l/s at 66.5 m. The pump is of axial split case type, horizontally mounted, with dual flows’ radial impeller. The design pressure is not less than 10 bars. The pump velocity is not more than 1,500 rpm. The pump casing is in gray cast iron (GG-25). The impeller is in stainless steel (austeno- ferritic / duplex steel). The pumps’ sealing type is gland packing with square cross-sectioned rope. The pumps’ ball bearings are greased for life. They are fitted with digital thermal probes to detect unusual heating.

The mathematical equation of the network curve resulting from the hydraulic simulation is: H=0.0001xQ²-0.0007xQ+59.9 (at Min. water elevation H90%). The equation of the network min. curve is: H=0.0001xQ²+0.0007xQ+58.4 (at Max. water elevation H5%).

The Contractor shall update the pumping diagram according to the characteristics of the proposed pumps and define the corresponding technical requirements, including electrical values (motors’ power, contactors’ calibration, etc.). The hydraulic efficiency of a pump is not less than 75% for all the range of operation, whatsoever with 1 or 2 pumps simultaneously in operation at fixed speed. The pumping station is design to operate between 20% and 100% of the nominal capacity. The suction capacity of the pump NPSHr shall not be above 9.2 m for all the range of operation, and particularly with a single pump in operation, at a flow around 138 l/s. The pumps motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 80 K, degree of protection IP55, natural cooling with fan. The rated motor efficiency is according to IEC 60034-30 class high efficiency IE2. The pump constructor shall supply the motors: the proper operation of the whole pumping unit (pump + motor) is under the responsibility of the pump constructor. The motor power is selected taking into account the system efficiency and a security factor of 10% above the restrictive functioning point. In the present case this is with a single pump in operation according to the above diagram. The calculated rated motor power is thereby 131 kW. The actual rated power according to constructor standard will not be less than this value. The Contractor shall update this calculation according to the actual hydraulic efficiency of the proposed pump and offer the corresponding motor standard size. The calculation of the motor electrical protections shall be conducted with this selected value. The windings are equipped with thermal probes and anti-condensation heaters. The motors ball bearings are greased for life.

5.2.1.2 Pumping units for SP-1B The output of the hydraulic calculation states a total flow of 84 l/s at 52 m. Taking into account usual head losses in a pumping station of about 1.5 m, the rated pumping head is 53.5 m. The total flow of the pumping station is split into 2 pumps. There is no stand-by pump. The rated point of each pump is thereby 42 l/s at 53.5 m. The pump is of axial split case type, horizontally mounted, with dual flows’ radial impeller. The design pressure is not lesser than 10 bars. The pump velocity is not more than 3,000 rpm. The pump casing is in gray cast iron (GG-25). The impeller is in stainless steel (austeno- ferritic / duplex steel). The pumps’ sealing type is gland packing with square cross-sectioned rope. The pumps’ ball bearings are greased for life. They are fitted with digital thermal probes to detect unusual heating.

H (mWC) Pump Diagram - Group 1: Jora de Jos SP-1B 70 Qmin Network max. curve

1 pump 60 2900 tr/min

2 pumps 2900 tr/min

1 pump 50 2577 tr/min

Network min. curve

0 Q (l/s) 0 0 0 5 0 1 The mathematical equation of the network curve resulting from the hydraulic simulation is: H=0.0006xQ²+0.0013xQ+49.3 (at Min. water elevation). The equation of the network min. curve is: H=0.0006xQ²+0.0013xQ+47.8 (at Max. water elevation).

The Contractor shall update the pumping diagram according to the characteristics of the proposed pumps and define the corresponding technical requirements, including electrical values (motors’ power, contactors’ calibration, etc.). The hydraulic efficiency of a pump is not less than 75% for all the range of operation, whatsoever with 1 or 2 pumps simultaneously in operation at fixed speed. The pumping station is design to operate between 20% and 100% of the nominal capacity. The suction capacity of the pump NPSHr shall not be above 9.7 m for all the range of operation, and particularly with a single pump in operation, at a flow around 46 l/s. The pumps motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 80 K, degree of protection IP55, natural cooling with fan. The rated motor efficiency is according to IEC 60034-30 class high efficiency IE2. The pump constructor shall supply the motors: the proper operation of the whole pumping unit (pump + motor) is under the responsibility of the pump constructor.

The motor power is selected taking into account the system efficiency and a security factor of 10% above the restrictive functioning point. In the present case this is with a single pump in operation according to the above diagram. The calculated rated motor power is thereby 35 kW. The actual rated power according to constructor standard will not be less than this value. The Contractor shall update this calculation according to the actual hydraulic efficiency of the proposed pump and offer the corresponding motor standard size. The calculation of the motor electrical protections shall be conducted with this selected value. The windings are equipped with thermal probes and anti-condensation heaters. The motors ball bearings are greased for life.

5.2.1.3 Pumping units for SP-1C The output of the hydraulic calculation states a total flow of 571 l/s at 148 m. Taking into account usual head losses in a pumping station of about 1.5 m, the rated pumping head is 149.5 m. The total flow of the pumping station is split into 2 pumps. There is no stand-by pump. The rated point of each pump is thereby 286 l/s at 149.5 m. The pump is of axial split case type, horizontally mounted, with dual flows’ radial impeller. The design pressure is not lesser than 16 bars. The pump velocity is not more than 1,500 rpm. The pump casing is in gray cast iron (GG-25). The impeller is in stainless steel (austeno- ferritic / duplex steel). The pumps’ sealing type is gland packing with square cross-sectioned rope. The pumps’ ball bearings are greased for life. They are fitted with digital thermal probes to detect unusual heating. The following diagram indicates the pumping network curve with an example of pumps’ curve.

The mathematical equation of the network curve resulting from the hydraulic simulation is: H=0.00004xQ²+0.0032xQ+134.6 (at Min. water elevation). The equation of the network min. curve is: H=0.0001xQ²+0.0007xQ+133.1 (at Max. water elevation).

The Contractor shall update the pumping diagram according to the characteristics of the proposed pumps and define the corresponding technical requirements, including electrical values (motors’ power, contactors’ calibration, etc.). The hydraulic efficiency of a pump is not less than 75% for all the range of operation, whatsoever with 1 or 2 pumps simultaneously in operation. The suction capacity of the pump NPSHr shall not be above 9.0 m for all the range of operation, and particularly with a single pump in operation, at a flow around 370 l/s. The pumps motor is asynchronous, squirrel cage induction type, designed for three-phase 6000 V-50 Hz voltage, insulation class F, temperature rise 80 K, degree of protection IP55, natural cooling with fan. The rated motor efficiency is according to IEC 60034-30 class high efficiency IE2. The pump constructor shall supply the motors: the proper operation of the whole pumping unit (pump + motor) is under the responsibility of the pump constructor.

The motor power is selected taking into account the system efficiency and a security factor of 10% above the restrictive functioning point. In the present case this is with a single pump in operation according to the above diagram. The calculated rated motor power is thereby 756 kW. The Contractor shall update this calculation according to the actual hydraulic efficiency of the proposed pump and offer the corresponding motor standard size. The calculation of the motor electrical protections shall be conducted with this selected value. The windings are equipped with thermal probes and anti-condensation heaters. The motors ball bearings are greased for life.

The dewatering system comprises of:  A dewatering pumping unit plus one for quicker start-up of the system and for spare;  Ancillary equipment. The rated point of each pump is 10 l/s at 10 m. The pump is of centrifugal submersible type, vertically mounted. The pumps’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP68. The motor power is selected taking into account the system efficiency and a security factor of 20%. The pumps are installed in a sump pit volume 0.65 m3, size 0.8 m x 0.8 m x 1.0 m depth, which is sized for 15 starts per hour of the motors, alternatively used for each pump. The dewatering pumps are interconnected and connected to a discharge pipe with ND 80 mm. For separated discharge of each pump, 2 non-return valves and 2 manual gate valves ND 80 mm are installed, with dismantling joints in between. For dewatering regulations’ purposes, the sump pit is equipped with 6 adjustable water level sensors. 5.2.3 Water hammer protection system 5.2.3.1 Water hammer protection system for SP-1A The water hammer protection system comprises of:  A pressure vessel 1,500 l ND 1,000 mm NP 10 bars, with an initial pressure of 0.5 bars. The air volume at dynamic pressure will be 0.3 m3;  A by-pass ND 400 mm NP 10 bars between suction pipes and discharge pipes of pumping station, to protect the irrigation network situated under the pressure vessel elevation;  1 air valve ND 60 mm special anti-shock (without abrupt closure) against surge alleviation, installed at high point at the end of the branch PTc. Air Inlet: for a depression of -0.2 bar, should the Air Valve bring an air flow of 0.15 m3/s and Air outlet: for overpressure of +0.2 bar, should the air valve discharge an air flow of 0.3 m3/s;  A compressor plus one for quicker start-up of the system and for spare;

 Ancillary pipes and equipment. The rated point of each compressor is 0.5 m3/h at 7 bars. These devices are interconnected with 2 non-return valves and 2 manual gate valves ND 25 mm and connected to the pressure vessel by pipes with ND 25 mm. The compressors’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. The motor power is selected taking into account the system efficiency and a security factor of 20%. The pressure vessel is equipped with a safety electric break-pressure valve with manual backup and a drain valve, all in ND 50 mm. The pressure vessel is equipped with a pressure gauge and for regulation purposes with 6 adjustable level sensors mounted on an external level visualization system by transparent tube and a magnetic visual float or equivalent system.

5.2.3.2 Water hammer protection system for SP-1B

The water hammer protection system comprises of:  A pressure vessel 800 l ND 750 mm NP 10 bars, with an initial pressure of 0.0 bars. The air volume at dynamic pressure will be 0.1 m3;  A by-pass ND 250 mm NP 10 bars between suction pipes and discharge pipes of pumping station, to protect the irrigation network situated under the pressure vessel elevation;  1 air valve ND 60 mm, installed at high point at the end of the branch 3KP1. Air Inlet: for a depression of -0.2 bar, should the Air Valve bring an air flow of 0.15 m3/s and Air outlet: for overpressure of +0.2 bar, should the air valve discharge an air flow of 0.3 m3/s;  A compressor plus one for quicker start-up of the system and for spare;  Ancillary pipes and equipment. The rated point of each compressor is 4 m3/h at 7.8 bars. These devices are interconnected with 2 non-return valves and 2 manual gate valves ND 25 mm and connected to the pressure vessel by pipes with ND 25 mm. The compressors’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. The motor power is selected taking into account the system efficiency and a security factor of 20%. The pressure vessel is equipped with a safety electric break-pressure valve with manual backup and a drain valve, all in ND 50 mm. The pressure vessel is equipped with a pressure gauge and for regulation purposes with 6 adjustable level sensors mounted on an external level visualization system by transparent tube and a magnetic visual float or equivalent system.

5.2.3.3 Water hammer protection system for SP-1C

The water hammer protection system comprises of:

 A pressure vessel 15,000 l ND 2,100 mm NP 16 bars, with an initial pressure of 8.4 bars. The air volume at dynamic pressure will be 9.2 m3;  A perforated check valve ND 400 mm installed upstream the pressure vessel, with a perforation diameter of 134 mm;  1 air valve ND 60 mm, installed at high point at the end of the branch 3KP1. Air Inlet: for a depression of -0.2 bar, should the Air Valve bring an air flow of 0.15 m3/s and Air outlet: for overpressure of +0.2 bar, should the air valve discharge an air flow of 0.3 m3/s;  A compressor plus one for quicker start-up of the system and for spare;  Ancillary pipes and equipment; The rated point of each compressor is 6 m3/h at 14.3 bars. These devices are interconnected with 2 non-return valves and 2 manual gate valves ND 25 mm and connected to the pressure vessel by pipes with ND 25 mm. The compressors’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. The motor power is selected taking into account the system efficiency and a security factor of 20%. The pressure vessel is equipped with a safety electric break-pressure valve with manual backup and a drain valve, all in ND 50 mm. The pressure vessel is equipped with a pressure gauge and for regulation purposes with 6 adjustable level sensors mounted on an external level visualization system by transparent tube and a magnetic visual float or equivalent system.

5.2.4.1 Pipes and fittings for SP-1A The pipes and fittings between the basin and the pumping station have the following characteristics: steel NP 10 bars ND 500 mm. The main pipes in the pumping room have the following characteristics:  Pipes and fittings upstream the pumps are of steel NP 10 bars ND 400 mm;  Asymmetrical cones upstream the pumps have an angle of 10°;  Symmetrical cones downstream the pumps have an angle of 10°;  Pipes and fittings downstream the pumps are of steel NP 10 bars ND 300 mm;  Pipes and fittings for the by-pass are of steel NP 10 bars ND 400 mm.

The pipes and fittings between the pumping station and the flow-meter chamber have the following characteristics:  Discharge pipes and fittings are of steel NP 10 bars ND 300 mm;

 Main pipe is of steel NP 10 bars ND 400 mm;  Pipe connection from the main pipe to the pressure vessel is of steel NP 10 bars ND 200 mm.

5.2.4.2 Pipes and fittings for SP-1B The pipes and fittings between the basin and the pumping station have the following characteristics: steel NP 10 bars ND 300 mm. The main pipes in the pumping room have the following characteristics:  Pipes and fittings upstream the pumps are of steel NP 10 bars ND 250 mm;  Asymmetrical cones upstream the pumps have an angle of 10°;  Symmetrical cones downstream the pumps have an angle of 10°;  Pipes and fittings downstream the pumps are of steel NP 10 bars ND 200 mm;  Pipes and fittings for the by-pass are of steel NP 10 bars ND 250 mm. The pipes and fittings between the pumping station and the flow-meter chamber have the following characteristics:  Discharge pipes and fittings are of steel NP 10 bars ND 200 mm;  Main pipe is of steel NP 10 bars ND 300 mm;  Pipe connection from the main pipe to the pressure vessel is of steel NP 10 bars ND 200 mm.

5.2.4.3 Pipes and fittings for SP-1C The pipes and fittings between the basin and the pumping station have the following characteristics: steel NP 10 bars ND 800 mm. The main pipes in the pumping room have the following characteristics:  Pipes and fittings upstream the pumps are of steel NP 10 bars ND 500 mm;  Asymmetrical cones upstream the pumps have an angle of 10°;  Symmetrical cones downstream the pumps have an angle of 10°;  Pipes and fittings downstream the pumps are of steel NP 16 bars ND 500 mm. The pipes and fittings between the pumping station and the flow-meter chamber have the following characteristics:  Discharge pipes and fittings are of steel NP 16 bars ND 500 mm;  Main pipe is of steel NP 16 bars ND 700 mm;  Pipe connection from the main pipe to the pressure vessel is of steel NP 16 bars ND 400 mm.

5.2.4.4 Ancillary Pipes and fittings The ancillary pipes in the pumping room have the following characteristics:

 Pipes and fittings for the dewatering system are of steel NP 10 bars ND 80 mm;  Pipes and fittings for the water hammer protection system are of steel NP 10 bars ND 25 mm;  Pipes and fittings to drain the discharge pipes are of steel NP 10 bars ND 50 mm.

5.2.5 Valves

5.2.5.1 Valves for SP-1A The main valves in the pumping room have the following characteristics:  2 valves upstream the pumps are of gate valve type, manually driven NP 10 bars ND 400 mm. They are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 valves downstream the pumps are of gate valve type, electrically driven with manual backup system NP 10 bars ND 300 mm. They are fitted with visual position indicator, torque limiter and digital position switches “Open” and “Close”. The valves are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 non-return valves downstream the pumps are of flapper type, NP 10 bars ND 300 mm;  2 valves for the by-pass are of gate valve type, manually driven NP 10 bars ND 400 mm;  1 non-return valve for the by-pass is of flapper type, NP 10 bars ND 400 mm. It is equipped with 1 dismantling joints, self-locked with flanged sleeves;  Valves for the water hammer protection system: o 1 gate valve, manually driven NP 10 bars ND 200 mm, for the pressure vessel. It is equipped with 1 dismantling joint, self-locked with flanged sleeves; o 1 break-pressure valve, electrically driven with manual backup NP 10 bars ND 50 mm, for the pressure vessel; o 1 drain valve manually driven NP 10 bars ND 50 mm, for the pressure vessel; o 2 non-return valves NP 10 bars ND 50 mm, for the compressors; o 2 gate valves, manually driven NP 10 bars ND 25 mm, for the compressors.

5.2.5.2 Valves for SP-1B The main valves in the pumping room have the following characteristics:  2 valves upstream the pumps are of gate valve type, manually driven NP 10 bars ND 250 mm. They are equipped with 2 dismantling joints, self-locked with flanged sleeves;

 2 valves downstream the pumps are of gate valve type, electrically driven with manual backup system NP 10 bars ND 200 mm. They are fitted with visual position indicator, torque limiter and digital position switches “Open” and “Close”. The valves are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 non-return valves downstream the pumps are of flapper type, NP 10 bars ND 200 mm;  2 valves for the by-pass are of gate valve type, manually driven NP 10 bars ND 250 mm;  1 non-return valve for the by-pass is of flapper type, NP 10 bars ND 250 mm. It is equipped with 1 dismantling joints, self-locked with flanged sleeves;  Valves for the water hammer protection system: o 1 gate valve, manually driven NP 10 bars ND 200 mm, for the pressure vessel. It is equipped with 1 dismantling joint, self-locked with flanged sleeves; o 1 break-pressure valve, electrically driven with manual backup NP 10 bars ND 50 mm, for the pressure vessel; o 1 drain valve manually driven NP 10 bars ND 50 mm, for the pressure vessel; o 2 non-return valves NP 10 bars ND 50 mm, for the compressors; o 2 gate valves, manually driven NP 10 bars ND 25 mm, for the compressors.

5.2.5.3 Valves for SP-1C The main valves in the pumping room have the following characteristics:  2 valves upstream the pumps are of gate valve type, manually driven NP 10 bars ND 500 mm. They are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 valves downstream the pumps are of gate valve type, electrically driven with manual backup system NP 16 bars ND 400 mm. They are fitted with visual position indicator, torque limiter and digital position switches “Open” and “Close”. The valves are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 non-return valves downstream the pumps are of flapper type, NP 16 bars ND 400 mm.  Valves for the water hammer protection system: o 1 gate valve, manually driven NP 16 bars ND 400 mm, for the pressure vessel. It is equipped with 1 dismantling joint, self-locked with flanged sleeves; o 1 perforated check valve ND 400 mm installed upstream the pressure vessel, with a perforation diameter of 134 mm; o 1 break-pressure valve, electrically driven with manual backup NP 10 bars ND 50 mm, for the pressure vessel; o 1 drain valve manually driven NP 10 bars ND 50 mm, for the pressure vessel;

o 2 non-return valves NP 10 bars ND 50 mm, for the compressors; o 2 gate valves, manually driven NP 10 bars ND 25 mm, for the compressors.

5.2.5.4 Ancillary valves The ancillary valves in the pumping room have the following characteristics:  Valves for the dewatering system: o 2 non-return valves NP 10 bars ND 80 mm; o 2 gate valves, manually driven NP 10 bars ND 80 mm;  2 gate valves, manually driven NP 10 bars ND 50 mm, for discharge pipes drainage.

The overhead travelling crane with a hoist capacity of 2 ton shall be reconditioned during a mechanical and electrical overhaul in workshop. The wearing parts are to be replaced by new ones.

5.2.7 Ventilation

The capacity of the ventilation devices is calculated as all the efficiency losses of the motors are converted into heat and to limit de internal temperature elevation of 5 degrees compared with the external temperature.

5.2.7.1 Ventilation for SP-1A The efficiency losses are estimated at 7% of the required power of the motors i.e. 17 kW. The corresponding capacity of the ventilation system is 13,924 m3/h. The total ventilation of the pumping room is divided into 2 fans. The rated point of each fan is thereby 6,962 m3/h at 1 mbar, taking into account head losses of 50 Pa for each air inlet and outlet. The fan is of window type, vertically mounted. It is equipped with an external protection grid with inclined flaps, which can be closed in winter. The fans’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55.

An air inlet is provided across from each fan on the other side of the pumping room. It is sized for a maximum air speed in the effective area of grid of 3 m/s, what gives 0.8 m2 per air inlet, taking into account a reduction factor of 20% between gross area and effective area. It is equipped with an external protection grid with inclined flaps, which can be closed in winter.

5.2.7.2 Ventilation for SP-1B The efficiency losses are estimated at 7% of the required power of the motors i.e. 5 kW. The corresponding capacity of the ventilation system is 4,095 m3/h. The total ventilation of the pumping room is realised with 1 fan. The rated point of the fan is thereby 4,095 m3/h at 1 mbar, taking into account head losses of 50 Pa for each air inlet and outlet. The fan is of window type, vertically mounted. It is equipped with an external protection grid with inclined flaps, which can be closed in winter. The fan’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. An air inlet is provided across from fan on the other side of the pumping room. It is sized for a maximum air speed in the effective area of the grid of 3 m/s, what gives 0.5 m2 per air inlet, taking into account a reduction factor of 20% between gross area and effective area. It is equipped with an external protection grid with inclined flaps, which can be closed in winter.

5.2.7.3 Ventilation for SP-1C The efficiency losses are estimated at 7% of the required power of the motors i.e. 86 kW. The corresponding capacity of the ventilation system is 70,438 m3/h. The total ventilation of the pumping room is divided into 2 fans. The rated point of each fan is thereby 35,219 m3/h at 1 mbar, taking into account head losses of 50 Pa for each air inlet and outlet. The fan is of window type, vertically mounted. It is equipped with an external protection grid with inclined flaps, which can be closed in winter. The fans’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. An air inlet is provided across from each fan on other side of the pumping room. It is sized for a maximum air speed in the effective area of grid of 3 m/s, what gives 3.9 m2 per air inlet, taking into account a reduction factor of 20% between gross area and effective area. It is equipped with an external protection grid with inclined flaps, which can be closed in winter.

5.3.1 Power supply

The pumping station SP-1 A and SP-1 B shall be supplied by low voltage three-phase 400 V- 50 Hz. The pumping station SP-1 C shall be supplied by high voltage three phase 6000 V-50 Hz. The grounding system is TN-C-S according to IEC standard. These outdoor utilities are under the responsibility of the electric supply company. 5.3.2 Power requirements

For the purpose of the power requirement calculation, the average power of the main pumps’ motors is taken into account when all the pumps are operating together. It differs from the maximum power calculated in the “Pumping units” chapter as the unitary flow is much less with all the pumps operating together than with a single one. For SP-1A, the main pumps motor average consumption is 127 kW when all the pumps are operating together, taking into account a rated motor efficiency at 93%. For SP-1B, the main pumps motor average consumption is 37 kW when all the pumps are operating together, taking into account a rated motor efficiency at 93%. For SP-1C, the main pumps motor average consumption is 660 kW when all the pumps are operating together, taking into account a rated motor efficiency at 93%. The ancillary equipment requires 65 kW, including a safety margin of 20 kW for maintenance purposes. The total power LV requirement of the pumping station is thereby 392 kW.

The total power HV requirement of the pumping station is thereby 1321 kW.

The low voltage electrical switch- and control gears include power and control equipment to be clearly separated in the cabinets. They are equipped with safety features according international and national regulations and comprises of:  1 main switch- and controlgear comprising o 1 incoming unit and general protection for the 630 kVA incoming power supply; o 1 feeder unit for the switch- and control gear for ancillaries; o 4 motor starter units for the main pumps with variable frequency drive; o 1 automatic reactive power compensation unit for the pumping station;  1 switch- and control gear for ancillaries;  1 pumping station control gear (control panel) for automation, monitoring and manual control;  1 switch gear for the operation in the non-irrigation period comprising: o 1 incoming and protection unit for the 63 kVA power supply; o Power distribution for lighting and sockets; o Power distribution for the anti-condensation heaters;

o Motor starters for the drainage pumps;  10 remote control panels IP 65 in the pumping room, for the main pumps, the drainage pumps and the compressors;  1 wall insulating switch for the crane, according to local safety regulation.

 The general incoming and protection switch gear comprises of (not limited to): o 1 main circuit breaker 1000 A for the main power incoming; o 1 monitoring and protection device for input voltages and currents (voltage fluctuations, cuts and phase reversal, isolation defect, etc.); o 1 multifunction data-logger: voltage, current, active and reactive power, power factor, frequency, peak values; o 1 general surge protection; o 1 circuit breaker 160 A for the automatic plant for reactive power compensation of 75 kVAR; o 1 circuit breaker 80 A for the switch- and control gear for ancillaries; o 1 busbar Cu 60x8 mm per phase, Icc = 21.4 ; o 1 ground bus; o Heating, ventilation and lighting inside the switch gear, including control and protections.  The front door of the general incoming and protection switch gear includes: o 1 white LED indicating the presence of voltage from the main power incoming; o 1 red LED indicating a default from input voltages and currents; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 display of the data-logger; o 1 socket 230 V + G 16 A, 1 socket three-phase 400 V + G 32 A, 1 socket 24 V; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

5.3.5 Motor starter switch gear with Variable Frequency Drive for SP-1A

 The motor starter switch gear comprises of (not limited to):

o 1 motor protection circuit breaker 315 A; o 1 multifunction Motor Protection Relay (MPR) to protect the motor either with use of Variable Frequency Drive (VFD) or by direct starting (by-pass of the VFD) for: - Overload; - Stator winding over-temperature; - Short Circuit; - Locked Rotor; - Too frequent start; - Unbalance/single phasing; - Phase reversal; - Under-voltage; o 1 contactor 250 A; o 1 double switch 250 A with mechanical interlock. This device enables to by-pass manually the Variable Frequency Drive in case of default and to operate the motor with direct starting with auxiliary contact to signal position to PLC; o 1 Variable Frequency Drive (VFD) enabling to modify the motors speed from 60% et 100%; o 1 double switch 250 A with mechanical interlock. This device enables to isolate the Variable Frequency Drive when using the by-pass; o Control circuits comprises of relays and control voltage protections; o Part of the busbar Cu 60x8 mm; o Cable termination equipment; o Part of the switchgear ground bus; o Heating, ventilation and lighting inside the cabinet, including control and protections.

 The front door of the motor starter switchboard includes: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 ammeter with a selector switch 4-position “0 – Phase 1 – Phase 2 – Phase 3”, including current transformer; o 1 green LED indicating the pump is operating; o 1 red LED indicating a default from Motor Protection Relay (MPR); o 1 red LED indicating a default from Variable Frequency Drive (VFD); o 1 yellow LED indicating that the by-pass is operating; o 1 potentiometer for the Variable Frequency Drive (VFD); o 1 hour-meter; o 1 selector switch 3-position "Manual - 0 - Auto" for the pumps’ operating mode;

5.3.6 Motor starter switch gear with Variable Frequency Drive for SP-1B

 The motor starter switch gear comprises of (not limited to): o 1 motor protection circuit breaker 100 A; o 1 multifunction Motor Protection Relay (MPR) to protect the motor either with use of Variable Frequency Drive (VFD) or by direct starting (by-pass of the VFD) for: - Overload; - Stator winding over-temperature; - Short Circuit; - Locked Rotor; - Too frequent start; - Unbalance/single phasing; - Phase reversal; - Under-voltage;

o 1 contactor 100 A; o 1 double switch 100 A with mechanical interlock. This device enables to by-pass manually the Variable Frequency Drive in case of default and to operate the motor with direct starting with auxiliary contact to signal position to PLC; o 1 Variable Frequency Drive (VFD) enabling to modify the motors speed from 60% et 100%; o 1 double switch 100 A with mechanical interlock. This device enables to isolate the Variable Frequency Drive when using the by-pass; o Control circuits comprises of relays and control voltage protections; o Part of the busbar Cu 60x8 mm; o Cable termination equipment; o Part of the switchgear ground bus; o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the motor starter switchboard includes: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 ammeter with a selector switch 4-position “0 – Phase 1 – Phase 2 – Phase 3”, including current transformer; o 1 green LED indicating the pump is operating; o 1 red LED indicating a default from Motor Protection Relay (MPR);

o 1 red LED indicating a default from Variable Frequency Drive (VFD); o 1 yellow LED indicating that the by-pass is operating; o 1 potentiometer for the Variable Frequency Drive (VFD); o 1 hour-meter; o 1 selector switch 3-position "Manual - 0 - Auto" for the pumps’ operating mode;

 The switch- and control gear for ancillaries comprises of (not limited to): o 1 main circuit breaker 63 A; o 6 motor starter devices comprising motor protection circuit breaker and 6 reversing contactors for the main valves’ actuators; o 6 motor starter devices comprising motor protection circuit breaker and 6 contactors for the compressors; o 5 motor starter devices comprising motor protection circuit breaker and 5 contactors for the fans in the pumping room; o 1 thermo-magnetic motor protection circuit breaker and 1 contactor for the fan in the electrical room; o 1 circuit breaker for the command, automation and remote control switch- and control gear; o Circuit breakers for the water hammer protection system valves’ actuators; o Control circuits comprises of relays and control voltage protections; o 1 busbar Cu 25x4 mm per phase; o 1 ground bus o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the cabinet for ancillaries includes: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 6 green LED indicating the compressors are operating; o 6 red LED indicating a default from the compressors; o 6 hour-meters for the compressors; o 3 blinking white LED indicating the water hammer protection systems’ valve is opening. The LED remain stationary when the valve is fully opened;

o 3 blinking white LED indicating the water hammer protection systems’ valve is closing. The LED remain stationary when the valve is fully closed; o 3 red LED indicating a default from water hammer protection systems’ valve; o 3 selector switch 3-position "Manual - 0 - Auto" for the water hammer protection systems’ operating mode; o 6 blinking white LED indicating the main pumps’ valves are opening. The LED remain stationary when the valves are fully opened; o 6 blinking white LED indicating the main pumps’ valves are closing. The LED remain stationary when the valves are fully closed; o 6 red LED indicating a default from the main pumps’ valves; o 6 selectors switch 3-position "Manual - 0 - Auto" for the main pumps’ valves’ operating mode; o 5 green LED indicating the fans of pumping room are operating; o 5 red LED indicating a default from the fans of pumping room; o 5 selectors switch 3-position "Manual - 0 - Auto" for the fans’ operating mode of pumping room; o 1 green LED indicating the fan of electrical room is operating; o 1 red LED indicating a default from the fan of electrical room; o 1 selector switch 3-position "Manual - 0 - Auto" for the fans’ operating mode of electrical room; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

 The command, automation and remote control switch- and control gear comprises of (not limited to): o 1 Programmable Logic Controller (PLC) for managing the automatic operation and safeties (manual operation is not dependent of the controller). This unit has the necessary digital and analogical input and output cards as well as memory to monitor and store vital data and communication cards ensuring dialogue with the Remote Terminal Unit (RTU); o 1 Remote Terminal Unit (RTU) for SCADA purposes, with GSM telecommunication modem and antenna; o The terminal blocks for connecting all the equipment to the Programmable Logic Controller (PLC); o 1 Uninterruptible Power Supply (UPS) 50 Ah allocated to the Programmable Logic Controller (PLC), the Remote Terminal Unit (RTU) and the instrumentation; o Arresters’ modules for the measuring equipment (power and signal), for the Programmable Logic Controller (PLC) and for the Remote Terminal Unit (RTU);

o Control circuits comprises of relays and control voltage protections; o 1 ground bus; o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the command, automation and remote control switch- and control gear includes: o 1 white LED indicating the presence of main voltage; o 1 white LED indicating the presence of voltage from the Uninterruptible Power Supply (UPS); o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 Human Machine Interface (HMI) for: - Visualization of alarms; - Visualization of sensors’ states and analogical measurements; - Visualization and adjustment of control parameters: level thresholds, flow threshold, pressure thresholds, timers, etc.; o 3 numerical indicators for the measured flow; o 1 numerical indicator for the water level in the basin; o 1 red LED indicating an alarm for low water level in the basin; o 2 red LED indicating alarms for high and low water levels in the discharge basin; o 6 yellow LED indicating operating water levels in the discharge basin; o 6 red LED indicating alarms for high and low pressure in the discharge main pipe; o 1 red LED indicating a default from the Programmable Logic Controller (PLC); o 1 red LED indicating a default from the Remote Terminal Unit (RTU); o 1 red LED indicating a default from the Uninterruptible Power Supply (UPS); o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

5.3.9 Secondary input and protection switch gear

 The secondary incoming and protection switch gear comprises of (not limited to): o 1 main circuit breaker 32 A for the secondary power incoming; o 1 monitoring device for input voltages, currents and power, according to the requirements of the electrical supply company; o 1 circuit breaker 25 A downstream the monitoring device.

 The lighting and sockets switch gear comprises of (not limited to):

o 1 main switch 32 A for connection to the switch- and control gear for ancillaries. This device enable to switch manually from the secondary power supply used in winter to the main power supply used during the irrigation period; o 1 surge protection; o 2 motor starter devices comprising motor protection circuit breaker 10 A and 2 contactors for the drainage pumps; o 1 circuit breaker 6 A for the crane; o Branch circuit breakers for the different sockets and lighting groups; o Branch circuit breakers for anti-condensation resistors for the main motors and for the switch gears; o Box with step-down transformer 220 / 36 V.  The front door of the lighting and sockets switch gear includes: o 2 green LED indicating the drainage pumps are operating; o 2 red LED indicating a default from the drainage pumps; o 2 hour-meters for the drainage pumps; o 1 selector switch 3-position "Manual - 0 - Auto" for the drainage pumps’ operating mode.

5.3.11 High voltage electrical switch gears

The high voltage electrical switch gears are equipped with safety features according international and national regulations and comprises of:  1 general incoming and protection switch gear for the 1,600 kVA incoming power supply;  1 voltage measuring switch gear;  2 motor starter switch gears;  1 automatic plant for reactive power compensation. The switchgears for power equipment (general input and protection and motor starter) shall be combined by using a single section of busbars.

5.3.12 High voltage General incoming and protection switch gear

 The general incoming and protection switch gear comprises of (not limited to): o 1 main removable circuit breaker 630 A for the main power incoming; o 3 current transformers 150/5 A, for counting and for the protection; o 1 disconnector for grounding; o 1 busbar Cu 60x8 mm per phase, Icc = 31.5 kA; o 1 ground bus;

o Heating, ventilation and lighting inside the switch gear, including control and protections.  The front door of the general incoming and protection switch gear includes: o 1 white LED indicating the presence of voltage from the main power incoming; o 1 red LED indicating a default from input voltages and currents; o 3 ammeters; o 1 Measuring devices (active and reactive) power installed in the measuring cabinet.

5.3.13 High voltage measuring switch gear

 The high voltage measuring switch gear comprises of (not limited to): o 1 fuse 2 A for the voltage transformer protection; o 1 voltage transformers 6000/100/√3, for counting and for the protection; o 1 disconnector for grounding; o Part of the busbar Cu 60x8 mm; o 1 ground bus; o Heating, ventilation and lighting inside the switch gear, including control and protections.  The front door of the transformer input of voltage measuring switch gear includes: o 1 white LED indicating the presence of voltage; o 1 voltmeter.

5.3.14 High voltage motor starter switch gear

 The motor starter switch gear comprises of (not limited to): o 1 removable motorized circuit breaker 630 A; o 2 current transformers 100/5 A, for the protection; o 1 disconnector for grounding; o 1 multifunction Motor Protection Relay (MPR) for: - Overload; - Stator winding over-temperature; - Short Circuit; - Locked Rotor; - Too frequent start; - Unbalance/single phasing; - Phase reversal; - Under-voltage; o Part of the busbar Cu 60x8 mm; o 1 ground bus;

o Heating, ventilation and lighting inside the switch gear, including control and protections.

 The front door of the motor starter switchboard includes: o 1 white LED indicating the presence of voltage; o 1 push-button "Lamp testing"; o 1 push-button "Default reset"; o 1 ammeter with a selector switch 4-position “0 – Phase 1 – Phase 2 – Phase 3”; o 1 green LED indicating the pump is operating; o 1 red LED indicating a default from Motor Protection Relay (MPR); o 1 hour-meter; o 1 selector switch 3-position "Manual - 0 - Auto" for the pumps’ operating mode; o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation.

5.3.15 High voltage automatic plant for reactive power compensation switchgear

 The automatic plant for reactive power compensation switch gear comprises of (not limited to): o 1 removable circuit breaker 630 A for the automatic plant for reactive power compensation of 250 kVAR; o 2 current transformers 50/5 A, for the protection; o 1 disconnector for grounding; o Part of busbar Cu 60x8 mm; o 1 ground bus; o Heating, ventilation and lighting inside the switch gear, including control and protections.

5.3.16 Remote control panels for the main pumps

 These panels are located in front of the main pumps and comprise of:

o 1 white LED indicating the presence of voltage;

o 1 push-button "Lamp testing";

o 1 green LED indicating the pump is operating;

o 1 red LED indicating a default from motor or pump (bearings temperature);

o 1 red LED indicating a default from the switchgear;

o 1 push-button "Start" to start the pump;

o 1 push-button "Stop" to stop the pump;

o 1 blinking white LED indicating the main valve is opening. The LED remain stationary when the valve is fully opened;

o 1 blinking white LED indicating the main valve is closing. The LED remain stationary when the valve is fully closed;

o 1 red LED indicating a default from the main valve;

o 1 push-button "Open" to open the main valve;

o 1 push-button "Stop" to let the main valve partially opened (for first filling of the network by manual operation);

o 1 push-button "Close" to close the main valve;

 This panel is located near the drainage pumps and comprises:

o 2 green LED indicating the drainage pumps are operating;

o 2 red LED indicating a default from the drainage pumps;

o 2 push-buttons "Start" to start the pumps;

o 2 push-buttons "Stop" to stop the pumps;

 This panel is located near the compressors and comprises of:

o 2 green LED indicating the compressors are operating;

o 2 red LED indicating a default from the compressors;

o 2 push-buttons "Start" to start the compressors;

o 2 push-buttons "Stop" to stop the compressors;

o 1 blinking white LED indicating the water hammer protection systems’ valve is opening. The LED remain stationary when the valve is fully opened;

o 1 blinking white LED indicating the water hammer protection systems’ valve is closing. The LED remain stationary when the valve is fully closed;

o 1 red LED indicating a default from water hammer protection systems’ valve;

o 1 push-button "Open" to open the valves;

o 1 push-button "Close" to close the valves;

 The instrumentation and metering devices at the pumping station SP1 have the following characteristics:

o 6 pressure sensor/transmitters with analogical signals installed on the discharge pipes of each pump, for pressure measurement. They deliver measurement values of the discharge pressure at each pump. These sensors/transmitters delivers 4-20 mA signal as input into the PLC;

o 6 pressure gauges downstream the pumps;

o 6 pressure gauges downstream the discharge gate valves;

o 1 double pressure switch with digital signals installed on the discharge main pipe of SP-1A, for pressure detection. It shall switch if the discharge pressure is too low or too high. The pressure for alarms transmission is 1 bar above and below the extremes values of the discharge curve shown on the pump diagram: - 76 m = 7.4 bars: high pressure alarm; - 49 m = 4.8 bars: low pressure alarm;

o 1 double pressure switch with digital signals installed on the discharge main pipe of SP-1B, for pressure detection. It shall switch if the discharge pressure is too low or too high. The pressure for alarms transmission is 1 bar above and below the extremes values of the discharge curve shown on the pump diagram: - 64 m = 6.3 bars: high pressure alarm; - 38 m = 3.7 bars: low pressure alarm;

o 1 double pressure switch with digital signals installed on the discharge main pipe of SP-1C, for pressure detection. It shall switch if the discharge pressure is too low or too high. The pressure for alarms transmission is 1 bar above and below the extremes values of the discharge curve shown on the pump diagram: - 160 m = 15.7 bars: high pressure alarm; - 141 m = 13.8 bars: low pressure alarm;

o 1 pressure sensor/transmitter with analogical signals installed on each discharge main pipe, for pressure measurement. It delivers measurement values of the discharge pressure at the pumping station outlet. The transmitter shall be installed in or near the manhole for local monitoring and shall deliver the information as 4- 20 mA for the PLC;

o 1 ultrasonic flow-meter with analogical signal installed in the manhole on each discharge main pipe, for water flow measurement and integration capability to count and store the data of water volumes taken from water basin and delivered to the irrigation network. The flow meter will be of a type and model approved for use in Moldova for billing purpose. It delivers measurement values of the discharge flow at the pumping station. The transmitter shall be installed in or near the manhole for local monitoring and shall deliver the information as 4-20 mA for the PLC. Two indicators for flow and volumes are installed: one in the manhole and the other on the front door of the automation switch gear;

o 6 conductive water level switches with digital signal installed in the drainage sump pit, for water level detection. They deliver 4 water regulation signals and alarm signals if the water level is too low or too high. The level for signal transmission is as follows: - - 0.10 m: high level alarm; - - 0.20 m: Start pump Nr. 2; - - 0.25 m: Start pump Nr. 1; - - 0.55 m: Stop pump Nr. 2; - - 0.60 m: Stop pump Nr. 1; - - 0.70 m: low level alarm;

o 6 conductive water level switches with digital signal installed in each pressure vessel, for water level detection. They deliver 4 water regulation signals and alarm signals if the water level is too low or too high. For SP-1A, the level for signal transmission is as follows from the bottom (for a vertical vessel height 2,200 mm): - 2.00 m: high level alarm; - 1.95 m: Start compressor Nr. 2; - 1.90 m: Start compressor Nr. 1; - 1.85 m: Stop compressor Nr. 2; - 1.80 m: Stop compressor Nr. 1; - 0.74 m: low level alarm; For SP-1B, the level for signal transmission is as follows from the bottom (for a vertical vessel height 2,100 mm): - 2.01 m: high level alarm; - 1.96 m: Start compressor Nr. 2; - 1.91 m: Start compressor Nr. 1; - 1.86 m: Stop compressor Nr. 2; - 1.81 m: Stop compressor Nr. 1; - 0.60 m: low level alarm;

For SP-1C, the level for signal transmission is as follows from the bottom (for a vessel ND 2,100 mm): - 0.91 m: high level alarm; - 0.86 m: Start compressor Nr. 2; - 0.81 m: Start compressor Nr. 1; - 0.76 m: Stop compressor Nr. 2; - 0.71 m: Stop compressor Nr. 1; - 0.66 m: low level alarm;

o 3 temperature sensors with analogical signals, the first installed in the pumping room, the second in the electrical room and the third outside the building, for temperature measurement. They deliver measurement values in 4-20 mA to a transducer that allows converting the information of the temperature at each location;  The instrumentation and metering devices at the discharge basin SP-2 have the following characteristics:

o 1 level sensor with analogical signal installed in the basin, for water level detection, plus 2 float switches for alarm level. The sensor delivers information in 4-20 mA to a transducer that allows converting the information. It is delivered 6 water regulation signals and 2 alarm signals if the water level is too low or too high. The level for signal transmission is as follows: - 195.3 m: high level alarm; - 195.1 m: Stop pump Nr. 1; - 194.9 m: Stop pump Nr. 2; - 194.7 m: Start pump Nr. 1; - 194.5 m: Start pump Nr. 2; - 194.3 m: low level alarm. 5.4.2 Automation and Control philosophy

5.4.2.1 Operating modes  The pumping station can be operated in 3 different modes:

o Local manual mode: through the remote control panels and the cabinet for ancillaries. This level of control is widespread. The control is performed by switches in general 3-positions "Manual - 0 - Auto", push buttons "Start" - "Stop" or "Open" - "Close" for equipment controlled by the PLC. The hard wire basic safety devices are active for this mode (protections of the motor protection relay, temperatures in the motor windings or pump bearings, starting frequency, etc.);

o Local automatic mode: command through the PLC Human Machine Interface (HMI). The pumping station can run fully automatically. This level enable to have an overview of the status of the equipment, of alarms, to visualize measured values;

o Remote control mode: no commands through the remote control centre are foreseen. The dispatching centre will have only monitoring and data processing and storage functions. Data will be displayed on a screen of the supervision computer. At this level will also be performed the functions of alarm management, editing, archiving, diagnostic and maintenance support. 5.4.2.2 Control philosophy for ancillaries

The particular automatic control philosophy for the water hammer system is as follows:

o Assure that the selector switch of the water hammer system is in automatic mode;

o Check that the water level switch in the pressure vessel is not triggered with alarm signal for low water level;

o Select the compressor Nr. to operate according to the last compressor which was in operation: the other compressor is selected;

o Start the compressor;

o Wait until the water level switch to stop the compressor is triggered in the pressure vessel. If it is not triggered after 30 min (adjustable parameter), start the second compressor;

o Regulate the stop and start of the compressor according to the activation of the corresponding water level switches in the pressure vessel;

o When the compressor planned is not available (in "Manual" or "0" position or in default) the other available compressor shall start.

The particular automatic control philosophy for the drainage system is as follows:

o Check that the water level switch in the drainage sump pit is not triggered with alarm signal for low water level;

o Select the pump Nr. to operate according to the last pump which was in operation: the other pump is selected;

o Start the drainage pump when the corresponding water level switch is triggered;

o Start the second drainage pump when the corresponding water level switch is triggered;

o Regulate the stop and start of the 2 drainage pumps according to the activation of the corresponding water level switches;

o When the pump planned is not available (in "Manual" or "0" position or in default) the other available pump shall start. The automatic particular control philosophy for the ventilation system is as follows:

o Assure that the selector switch of the fan is in automatic mode;

o A fan is dedicated to 1 or 2 pumps;

o Start a fan when the following conditions are reached together: - One of the corresponding pumps is operating; - The temperature sensor in the pumping room indicates more than 25°C (adjustable parameter); - The temperature sensor in the pumping room indicates more than the temperature sensor outside the building;

o When the fan planned is not available (in "Manual" or "0" position or in default) another available fan shall start;  Stop a fan when one of the following conditions is reached:

o All the corresponding pumps are stopped;

o The temperature sensor in the pumping room indicates less than 20°C (adjustable parameter);

o The temperature sensor in the pumping room indicates less than the temperature sensor outside the building.

5.4.2.3 Control philosophy for SP-1A and SP-1B The regulation of the pumping station is made according to the water flow and the pressure required by the irrigation devices. The flow/pressure equation of the network resulting from the hydraulic simulation is:  For SP-1A: H=0.0001xQ²-0.0007xQ+59.9;  For SP-1B: H=0.0006xQ²+0.0013xQ+49.3. The number of operating pumps and the frequency drive of the motor will be determined to follow these network curves. The system is designed to supply water between 20% and 100% of the rated flow. The pumping station shall be stopped if the measured flow goes under 20%. The adjustable parameter below shall be adjusted at the HMI of the PLC. The status change of the different sensors must remain during 5 s (adjustable temporization for each sensor) before the PLC undertakes an action. The instruction for manual starting of pumping station operation is as follows:  Check that all relevant equipment (water hammer system, vacuum pump sytem, pumps, valves, electrical supply, instrumentation and control, etc. ) is available;  Assure that the selector switches of the pumps is in manual mode and of the other equipment is in automatic mode;  Assure that the discharge valve is closed;  Check that the water level measurement in the basin is not triggered with alarm signal for low level;

 Fill the main delivery pipe with water by starting one pump in manual mode (if it is not already filled). Some of the most distant hydrants have to be open. The gate valve downstream the operating pump has to be open at 25% to maintain a counter-pressure (monitored at the gauge) to create a head loss and enable a smooth filling;  Open a minimum of 20% of the hydrants;  Open completely the gate valve downstream the operating pump;  Switch the pump to automatic mode. The VFD shall automatically adjust its frequency to reach the set point corresponding to the flow after checking that the double pressure switch on the main delivery pipe indicates that the pipe is full of water;  The water hammer system starts in automatic mode: the compressors are operating until the beginning of the regulation phase (1st stop of all compressors indicating that the air raised the lower part of the pressure vessel);  The regulation phase of the pumps begins.

The particular automatic control philosophy of starting a pump in automatic mode is as follows:

o Assure that the selector switch of the pump is in automatic mode;

o Alternate the pump to start according to the last pump which was in operation: the other pump is selected;

o Check that the positions’ switch of the gate valve downstream the pump is triggered on the "Close" position. If it is not triggered, launch a "close" order of the valve and wait until the positions’ switch is triggered on the "Close" position;

o Close the valve of the vacuum pipe for priming the pump;

o Start the pump at minimum speed (i.e. 60% of the rated frequency) and increase the speed gradually;

o Increase the speed until the discharge pressure sensor of the pump delivers a measured value equal to the minimum pressure according to the equation of the network curve: - For SP-1A: 59 m = 5.8 bars, adjustable parameter; - For SP-1B: 48 m = 4.7 bars, adjustable parameter;

o Open the gate valve downstream the pump and wait until the positions’ switch is triggered on the "Open" position;

o Another pump cannot be started before the end of this sequence;

o Begin the regulation phase:

- According to the water flow measured by the flow-meter, accelerates or decelerates the frequency controlled drive to reach the pressure of the set point calculated with the flow/pressure equation. This pressure is measured by the pressure sensor of the discharge main pipe. The set point is calculated every 30 s (adjustable parameter) and implemented with the Proportional/Integral/Derivative function of the PLC (PID controller); - If the required pressure cannot be reached after 30 s (adjustable parameter) at the maximum frequency reduce the speed of the pump to the minimum frequency (i.e. 60% of the rated frequency) and start the other pump at the minimum frequency; - According to the water flow measured by the flow-meter, accelerates or decelerates the frequency drive of both pumps at the same speed to reach the pressure of the set point calculated with the flow/pressure equation; - If the required water flow is reduced to 130 l/s for SP-1A (adjustable parameter) or 40 l/s for SP-1B (adjustable parameter), the first running pump will be stopped and the other shall be set to its maximum speed before decelerating to meet the pressure of the set point;

o Check each 60 s (adjustable parameter) that the double pressure switch installed on the discharge main pipe is not out of the limits (see the chapter "Instrumentation and metering");

o A cool down time set for 10 min (adjustable parameter) will be used to ensure that the pump cools down after each stop prior to automatic restart based on the flow in the network. This can be by-passed by the operator if required by using the push-button "Default reset" on the motor starter switchboard;

o When the pump planned is not available (in "Manual" or "0" position or in default) another available pump shall start.

o If the VFD is out of order, it can be manually by-passed using the double switches provided for this purpose. When the pump station will be switched in the automatic mode again a pump with VFD will be first selected and the following regulation phase will be implemented: - According to the water flow measured by the flow-meter, accelerates or decelerates the frequency drive to reach the pressure of the set point calculated with the flow/pressure equation. This pressure is measured by the pressure sensor of the discharge main pipe. The set point is calculated every 30 s (adjustable parameter) and implemented with the Proportional/Integral/Derivative function of the VFD (PID controller); - If the required pressure cannot be reached after 30 s (adjustable parameter) at the maximum frequency start the other pump; - Reduce the speed of the former pump to the minimum frequency (i.e. 60% of the rated frequency);

- According to the water flow measured by the flow-meter, accelerates or decelerates the frequency drive of the pump to reach the pressure of the set point calculated with the flow/pressure equation; - If the required water flow is reduced to 130 l/s for SP-1A (adjustable parameter) or 40 l/s for SP-1B (adjustable parameter), the running pump with fixed speed will be stopped;  The sequence of stopping a pump is as follows:

o Stop the pump;

o Close the gate valve downstream the pump and wait until the positions’ switch is triggered on the "Closed" position;

o Open the valve of the vacuum pipe for priming the pump.

5.4.2.4 Control philosophy for SP-1C The regulation of the pumping station is made according to the water level in the discharge basin. The number of operating pumps will be determined for each level in the basin (see the chapter "Instrumentation and metering"). It is verified that the volume of regulation between the start level and the stop level of a pump is compatible with 6 starts per hour of the motors. The adjustable parameter below shall be adjusted at the HMI of the PLC. The status change of the different sensors must remain during 5 s (adjustable temporization for each sensor) before the PLC undertakes an action. The instruction for manual starting of pumping station operation is as follows:  Check that all relevant equipment (water hammer system, vacuum pump system, pumps, valves, electrical supply, instrumentation and control, etc. ) is available;  Assure that the selector switches of the pumps is in manual mode and of the other equipment is in automatic mode;  Assure that the discharge valve is closed;  Check that the water level measurement in the river is not triggered with alarm signal for low level;  Fill the main delivery pipe with water by starting one pump in manual mode (if it is not already filled). Some of the most distant hydrants have to be open. The gate valve downstream the operating pump has to be open at 25% to maintain a counter-pressure (monitored at the gauge) to create a head loss and enable a smooth filling;  Open completely the gate valve downstream the operating pump;  Switch the pump to automatic mode. The SS shall start progressively to reach the nominal point corresponding to the flow after checking that the double pressure switch on the main delivery pipe indicates that the pipe is full of water;

 The water hammer system starts in automatic mode: the compressors are operating until the beginning of the regulation phase (1st stop of all compressors indicating that the air raised the lower part of the pressure vessel);  The regulation phase of the pumps begins.

The particular automatic control philosophy of starting a pump in automatic mode is as follows:

o Start the pump;

o Wait until the discharge pressure sensor of the pump delivers a measured value equal to the minimum pressure according to the equation of the network curve (133 m = 13 bars, adjustable parameter);

o Begin the regulation phase: regulate the stop and start of the pumps according water level in the basin and the corresponding thresholds indicated in the PLC (see the chapter "Instrumentation and metering");

o A cool down time set for 10 min (adjustable parameter) will be used to ensure that the pump cools down after each stop prior to automatic restart based on the water level in the basin. This can be by-passed by the operator if required by using the push-button "Default reset" on the motor starter switchboard;

o If the SS is out of order, it can be manually by-passed using the double switches provided for this purpose.  The sequence of stopping a pump is as follows:

o Stop the pump;

o Open the valve of the vacuum pipe for priming the pump.

5.4.2.5 Processing failure and alarms

o In case of processed values out of their normal range, an alarm will be sent to the SCADA system: low level in the river, flood in pumping room, high and low pressure in the main discharge pipe. The pumps will not start or will be stopped with a 30 s delay between each (adjustable parameter);

o In case of VFD or soft starter failure, the double switches can be manually switched to the direct starting position. A global defect alarm for pump will be sent to the SCADA system;

o In case of failure of pump, dewatering pump and compressor, it will be stopped and the other standby similar equipment will automatically be started instead of the former one. A global defect alarm for the corresponding equipment will be sent to the SCADA system. If no standby equipment is available the pumps will be stopped with a 30 s delay between each (adjustable parameter);

o In case of any failure on other device, it will be stopped as well as further actions and an alarm will be sent to the SCADA system: global defect for pump and corresponding valves, for the vacuum system, for the drainage system, for the water hammer system, for the ventilation system. The pumps will be stopped with a 30 s delay between each (adjustable parameter);

o In case of total power failure of less than 1 s (adjustable parameter), the pumping station will restart automatically. If the power failure is of more than 1 s, all the equipment shall be stopped and the pumping station has to be restart by manual action as described in the instruction for manual starting of pump operation. 5.4.2.6 Processing data and curves

 The PLC shall provide the following data and curves:

o Daily water flow Q (m3/h and l/s) with a step of 1 hour (adjustable parameter);

o Daily water volume (m3) with a step of 1 hour (adjustable parameter) and cumulated value;

o Daily water level in the basin H (m) with a step of 1 hour (adjustable parameter);

o Daily discharge pressure P (bars) with a step of 1 hour (adjustable parameter);

o Daily hydraulic power consumption (kWh) = 9.81 x Q x P with a step of 1 hour (adjustable parameter) and cumulated value;

o Daily electrical power consumption (kWh) = √3 x U x I x cos φ, with φ = arctan (reactive power/active power) with a step of 1 hour (adjustable parameter) and cumulated value;

o Daily system efficiency (hydraulic power/electrical power) with a step of 1 hour (adjustable parameter) and cumulated value;

o Daily electrical power consumption / water volume (kWh/m3) with a step of 1 hour (adjustable parameter) and cumulated value;

o Monthly water flow (m3/h and l/s) with a step of 1 day;

o Monthly water volume (m3) with a step of 1 day and cumulated value;

o Monthly water level in the basin H (m) with a step of 1 day;

o Monthly discharge pressure data (bars) with a step of 1 day;

o Monthly hydraulic power consumption (kWh) = 9.81 x Q x H with a step of 1 day and cumulated value;

o Monthly electrical power consumption (kWh) = √3 x U x I x cos φ, with φ = arctan (reactive power/active power) with a step of 1 day and cumulated value;

o Monthly system efficiency (hydraulic power/electrical power) with a step of 1 day and cumulated value;

o Monthly electrical power consumption / water volume (kWh/m3) with a step of 1 day and cumulated value.

o Annual water flow (m3/h and l/s) with a step of 1 month;

o Annual water volume (m3) with a step of 1 month and cumulated value;

o Annual water level in the basin H (m) with a step of 1 month;

o Annual discharge pressure data (bars) with a step of 1 month;

o Annual hydraulic power consumption (kWh) = 9.81 x Q x H with a step of 1 month and cumulated value;

o Annual electrical power consumption (kWh) = √3 x U x I x cos φ, with φ = arctan (reactive power/active power) with a step of 1 month and cumulated value;

o Annual system efficiency (hydraulic power/electrical power) with a step of 1 month and cumulated value;

o Annual electrical power consumption / water volume (kWh/m3) with a step of 1 month and cumulated value.

The PLC input / output comprises of (not limited to):

DIG ANA. ANA. DIG. Designation . I O O I General input high voltage and protection switch gear 4 5 0 2 Presence of voltage from the main power 1 1 Circuit breaker opening from the main power 1 Default from input voltages and currents 1 1 Data-logger: voltage, current, active and reactive power 4 Default reset 1 Emergency stop 1

General input low voltage and protection switch gear 4 5 0 2 Presence of voltage from the main power 1 1 Circuit breaker opening from the main power 1 Default from input voltages and currents 1 1 Data-logger: voltage, current, active and reactive power 4 Default reset 1 Emergency stop 1

Automatic plant for reactive power compensation (HV and LV) 0 2 0 2 Default from automatic plant for reactive power compensation 2 2

High voltage motor starter switch gear (x2) 4 16 0 10 Presence of voltage 1 1 Default reset 1 Order start pump 1

DIG ANA. ANA. DIG. Designation . I O O I Order stop pump 1 Pump is operating 1 1 Default Motor Protection Relay 1 Bearing temperature 1 Stator winding temperature 1 Selector switch position "Auto" for the pumps operating 1 Selector switch position "Manu" for the pumps operating 1 Emergency stop 1

Switch- and control gear for ancillaries 0 90 0 100 Presence of voltage 1 1 Default reset 1 Order start compressor n°1-2-3-4-5-6 6 Order stop compressor n°1-2-3-4-5-6 6 compressor n°1-2-3-4-5-6 is operating 6 6 Default compressor n°1-2-3-4-5-6 6 6 Order open water hammer system valve 3 Water hammer system valve is opened 3 3 Order close water hammer system valve 3 Water hammer system valve is closed 3 3 Default water hammer system valve 3 3 Selector switch position "Auto" for the compressor n°1-2-3-4-5-6 operating 6

DIG ANA. ANA. DIG. Designation . I O O I Selector switch position "Manu" for the compressor n°1-2-3-4-5-6 operating 6 Order open main valve n°1-6 6 Main valve n°1-6 is opened 6 6 Main valve n°1-6 overtorque at opening 6 Order close main valve n°1-6 6 Main valve n°1-6 is closed 6 6 Main valve n°1-6 overtorque at closing 6 Order stop main valve n°1-6 6 Default main valve n°1-6 6 6 Order start Fan n°1-5 5 Fan n°1-5 is operating 5 5 Order stop Fan n°1-5 5 Order start fan electrical room 1 Order stop fan electrical room 1 Fan electrical room is operating 1 1 Default fan n°1-5 5 5 Default fan electrical room 1 1 Selector switch position "Auto" for the fan n°1-5 operating 5 Selector switch position "Manu" for the fan n°1-5 operating 5 Selector switch position "Auto" for the fan electrical room operating 1 Selector switch position "Manu" for the fan electrical room operating 1 Emergency stop 1

Command, Automation and remote control switch- and control gear 16 37 0 13 Presence of voltage 1 1 Default reset 1 Presence of voltage from Uninterruptible Power Supply 1 1 Default Uninterruptible Power Supply 1 1 Default from the Programmable Logic Controller 1 Default from the Remote Terminal Unit 1 1 Measurement of flow-meter (A-B-C) 3 Measurement of water level in the basin 1 Low water level in the basin 1 Alarm low water level in the basin 1 Pressure in the main pipe (A-B-C) 3 Pressure in the discharge pipe pump n°1-6 6 Low pressure in the discharge main pipe (A-B-C) 3 High pressure in the discharge main pipe (A-B-C) 3

DIG ANA. ANA. DIG. Designation . I O O I Alarm low pressure in the discharge main pipe (A-B-C) 3 Alarm high pressure in the discharge main pipe (A-B-C) 3 Water level in the drainage sump pit 6 Alarm high water level in the drainage sump pit 1 Water level in the pressure vessel (A-B-C) 18 Temperature in the pumping room 1 Temperature in the electrical room 1 Temperature outside the building 1 Emergency stop 1 Lighting and sockets switch gear 0 24 0 24 Order start drainage pump n°1-2 2 Order stop drainage pump n°1-2 2 Drainage pump n°1-2 is operating 2 2 Default drainage pump n°1-2 2 2 Selector switch position "Auto" for the drainage pump n°1-2 operating 2 Selector switch position "Manu" for the drainage pump n°1-2 operating 2

DIG ANA. ANA. DIG. Designation . I O O I Local control panel for the water hammer protection system (x3) 0 21 0 24 Signalling presence of voltage 1 Signalling compressor n°1-2 is operating 2 Signalling default compressor n°1-2 2 Push-button "Start" to start the compressor n°1-2 2 Push-button "Stop" to stop the compressor n°1-2 2 Signalling water hammer protection system valve is opened 1 Signalling water hammer protection system valve is closed 1 Signalling default water hammer protection system valve 1 Push-button "Open" to open the water hammer system valve 1 Push-button "Close" to close the water hammer system valve 1 Emergency stop 1

Analog Inputs : 40 Digital Inputs : 274 Analog Outputs : 8 Digital Outputs : 244

5.4.4.1 Structure of the system  The SCADA system is essentially defined by: o The instrumentation, metering devices and sensors in some equipment (see the chapters above), which determines information to be transmitted; o The PLC in each pumping station; o The number and distribution of the Remote Terminal Units (RTU): - At the SPP-1 pumping station; - At the SPP-2 pumping station; - At the SP-1 pumping station; - At the SP-2 pumping station;  The transmission media: GSM data – GPRS;  The supervisory station at the remote control center (1 for Jora de Jos irrigation scheme) equipped with: o A frontal communication device for remote transmission of the various Remote Terminal Units: - Query of the different RTU; - Decoding the information; - Information storage buffer before transmission to the supervisory computer; - Serial link with the supervisory computer following an adapted protocol; - Remote transmission of various Remote Terminal Units; o A supervisory computer with a software for piloting of all associated Remote Terminal Units, displaying synoptic screens, managing the data and to emit alarms: - Piloting of all associated RTU; - Synoptic display screen; - Data management (statistical treatments); - Defect management (statistical treatments); - Operating assistance (edition of logbooks); - Management of the graphics printer; o A printer for edition of logbooks; o An on-call terminal to alert operators in case of alarm, generating automatically an SMS using the wording of the defect; o An Uninterruptible Power Supply (UPS) 50 Ah.

5.4.4.2 Remote Terminal Units

 This unit handles all remote transmissions with the Supervisory Station at the control center. It receives information directly from the PLC.

5.4.4.3 Remote controlled parameters

 The following information will be exchanged through the SCADA system by status change: o Power failure in the pumping station: main circuit breaker opening, lack of tension, phase inversion, etc.); o Operational status of the command: "Manual - 0 - Auto"; o Operational status of each pump "On" - "Off"; o Global defect for each pump: thermal load and max current, frequent starts, temperature probes, etc.); o Global defect for the drainage system; o Global defect for the water hammer system; o Global defect for the ventilation system; o Water flows and volumes (once a day); o Water level alarms: - Low level in the basin; - Flood in pumping room; o Water level in the basin (once a day); o Pressure alarms: high and low pressure in the main discharge pipe; o PLC failure; o RTU failure; o UPS failure.

6. DETAILED ELECTROMECHANICAL AND ELECTRICAL WORKS FOR PUMPING STATION SP-2

6.1 INTRODUCTION

6.1.1 General description of the SP-2 pumping station

The SP-2 pump station is located to the west of the pump station SP-2, near the paved road Orhei – Jora de Jos. The pump station is a pressure pump station and is used for pumping water to its irrigation network. The facilities consist of the main following equipment:  Upstream the pumping station: o Water intakes in the basin; o The connecting pipes between the intakes and the pumping station;  In the pumping station: o The pumping units; o The pipes and fittings; o The valves: suction gate valves, discharge gate valves, non return valves; o Ancillaries: dewatering pumps, compressors, handling devices, ventilation, etc.; o Low voltage electrical switch gears; o Instrumentation and metering devices;  Downstream the pumping station: o The connecting pipes between the pumping station and a flow-meter chamber; o The flow-meter chamber.

The command, the number of pumps needed and their speed are determined according to the water flow measures by a flow meter installed in a chamber downstream the pumping station. The pumps will automatically shut down above a maximum pressure and below a minimum pressure in the network and below the minimum water level in the basin.

6.1.3 Scope of Work

The main hydro- and electro-mechanical works comprise of:  Dismantling of existing water intakes in the basin;  Installation of new water intakes with grid in the basin;  Dismantling of 6 existing pumping units;  Installation of 6 new pumping units;  Installation of a new dewatering system, including 2 dewatering pumping units, pipes and valves;  Installation of a water hammer protection system, including 6 compressors, 3 pressure vessels, pipes and valves;  Dismantling of existing pipes and fittings between the water intake and the pumping station inlet, in the pumping room and between the pumping station and a flow-meter chamber outside the pumping station;  Installation of new pipes and fittings between the water intake and the pumping station inlet, in the pumping room and between the pumping station and flow-meter chambers outside the pumping station;  Dismantling of 6 existing suction gate valves, 6 existing non return valves and 6 existing discharge gate valves in the pumping room;  Installation of 6 new suction gate valves, 6 non return valves in the pumping room and 6 new discharge gate valves;  Mechanical and electrical overhaul of the handling device and change of wearing parts;  Installation of 4 air inlets and 4 fans in the pumping room and 1 air inlet and 1 fan in the electrical room;

The main electrical works comprise of:  Dismantling of 16 existing main low voltage electrical switch gears and ancillaries’ switch gears;  Installation of 9 new main low voltage electrical switch gears, including an automation and remote control switch gear;  Installation of the interface equipment (electricity counter and auxiliaries) to the power supply company;  Dismantling of the existing lights and sockets equipment;

 Installation of a new lights and sockets equipment;  Dismantling of the existing cables and cable trays;  Installation of new cables and cable trays;  Dismantling of the existing grounding system;  Installation of a new grounding system;  Dismantling of the existing lightning protection system;  Installation of a new lightning protection system.

The works also comprise of:  Commissioning of the facilities;  Providing the Operator with O&M manual and as built drawings; Training of the operating staff.

6.2.1 Pumping units

6.2.1.1 Pumping units for SP-2A The output of the hydraulic calculation states a total flow of 101 l/s at 71 m. Taking into account usual head losses in a pumping station of about 1.5 m, the rated pumping head is 72.5 m. The total flow of the pumping station is splited into 2 pumps. There is no stand-by pump. The rated point of each pump is thereby 51 l/s at 72.5 m. The pump is of axial split case type, horizontally mounted, with dual flows’ radial impeller. The design pressure is not less than 10 bars. The pump velocity is not more than 1,500 rpm. The pump casing is in gray cast iron (GG-25). The impeller is in stainless steel (austeno- ferritic / duplex steel). The pumps’ sealing type is gland packing with square cross-sectioned rope. The pumps’ ball bearings are greased for life. They are fitted with digital thermal probes to detect unusual heating. The following diagram indicates the pumping network curve with an example of pumps’ curve.

The mathematical equation of the network curve resulting from the hydraulic simulation is: H=0.0003xQ²+0.0071xQ+68.8 (at Min. water elevation). The equation of the network min. curve is: H=0.0003xQ²+0.0071xQ+67.3 (at Max. water elevation). The Contractor shall update the pumping diagram according to the characteristics of the proposed pumps and define the corresponding technical requirements, including electrical values (motors’ power, contactors’ calibration, etc.). The hydraulic efficiency of a pump is not less than 75% for all the range of operation, whatsoever with 1 or 2 pumps simultaneously in operation at fixed speed. The pumping station is design to operate between 20% and 100% of the nominal capacity. The suction capacity of the pump NPSHr shall not be above 10.0 m for all the range of operation, and particularly with a single pump in operation, at a flow around 62 l/s. The pumps motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 80 K, degree of protection IP55, natural cooling with fan. The rated motor efficiency is according to IEC 60034-30 class high efficiency IE2. The motors shall be supplied by the pump constructor: the proper operation of the whole pumping unit (pump + motor) is under the responsibility of the pump constructor. The motor power is selected taking into account the system efficiency and a security factor of 10% above the restrictive functioning point. In the present case this is with a single pump in operation according to the above diagram. The calculated rated motor power is thereby 66 kW. The actual rated power according to constructor standard will not be less than this value. The Contractor shall update this calculation according to the actual hydraulic efficiency of the proposed pump and offer the corresponding motor standard size. The calculation of the motor electrical protections shall be conducted with this selected value. The windings are equipped with thermal probes and anti-condensation heaters. The motors ball bearings are greased for life.

6.2.1.2 Pumping units for SP-2B The output of the hydraulic calculation states a total flow of 168 l/s at 50 m. Taking into account usual head losses in a pumping station of about 1.5 m, the rated pumping head is 51.5 m. The total flow of the pumping station is split into 2 pumps. There is no stand-by pump. The rated point of each pump is thereby 84 l/s at 51.5 m. The pump is of axial split case type, horizontally mounted, with dual flows’ radial impeller. The design pressure is not less than 10 bars. The pump velocity is not more than 1,500 rpm. The pump casing is in gray cast iron (GG-25). The impeller is in stainless steel (austeno- ferritic / duplex steel). The pumps’ sealing type is gland packing with square cross-sectioned rope. The pumps’ ball bearings are greased for life. They are fitted with digital thermal probes to detect unusual heating.

H (mWC) Pump Diagram - Group 1: Jora de Jos SP-2B Qmin 60 Network max. curve

1 pump 1500 tr/min

2 pumps 50 1500 tr/min

1 pump 1327 tr/min

Network 40 min. curve

0 Q (l/s) 0 0 0 0 0 5 5 0 0 1 1 2

The mathematical equation of the network curve resulting from the hydraulic simulation is: H=0.00016xQ²+0.0073xQ+45.7 (at Min. water elevation). The equation of the network min. curve is: H=0.00016xQ²+0.0073xQ+46.2 (at Max. water elevation). The Contractor shall update the pumping diagram according to the characteristics of the proposed pumps and define the corresponding technical requirements, including electrical values (motors’ power, contactors’ calibration, etc.). The hydraulic efficiency of a pump is not less than 75% for all the range of operation, whatsoever with 1 or 2 pumps simultaneously in operation at fixed speed. The pumping station is design to operate between 20% and 100% of the nominal capacity. The suction capacity of the pump NPSHr shall not be above 9.8 m for all the range of operation, and particularly with a single pump in operation, at a flow around 105 l/s. The pumps motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 80 K, degree of protection IP55, natural cooling with fan. The rated motor efficiency is according to IEC 60034-30 class high efficiency IE2. The motors shall be supplied by the pump constructor: the proper operation of the whole pumping unit (pump + motor) is under the responsibility of the pump constructor.

6.2.1.3 Pumping units for SP-2C The output of the hydraulic calculation states a total flow of 218 l/s at 28 m. Taking into account usual head losses in a pumping station of about 1.5 m, the rated pumping head is 29.5 m. The total flow of the pumping station is split into 2 pumps. There is no stand-by pump. The rated point of each pump is thereby 109 l/s at 29.5 m. The pump is of axial split case type, horizontally mounted, with dual flows’ radial impeller. The design pressure is not lesser than 10 bars. The pump velocity is not more than 1,500 rpm. The pump casing is in gray cast iron (GG-25). The impeller is in stainless steel (austeno- ferritic / duplex steel). The pumps’ sealing type is gland packing with square cross-sectioned rope. The pumps’ ball bearings are greased for life. They are fitted with digital thermal probes to detect unusual heating.

H (mWC) Pump Diagram - Group 1: Jora de Jos SP-2C 40

Network max. curve Qmin 1 pump 1500 tr/min

2 pumps 1500 tr/min 30 1 pump 871 tr/min

Network min. curve

0 Q (l/s) 0 0 0 0 0 0 5 0 5 0 5 1 1 2 2

The mathematical equation of the network curve resulting from the hydraulic simulation is: H=0.00037xQ²+0.0039xQ+11.2 (at Min. water elevation). The equation of the network min. curve is: H=0.00037xQ²+0.0039xQ+9.7 (at Max. water elevation). The Contractor shall update the pumping diagram according to the characteristics of the proposed pumps and define the corresponding technical requirements, including electrical values (motors’ power, contactors’ calibration, etc.). The hydraulic efficiency of a pump is not less than 75% for all the range of operation, whatsoever with 1 or 2 pumps simultaneously in operation at fixed speed. The pumping station is design to operate between 20% and 100% of the nominal capacity. The suction capacity of the pump NPSHr shall not be above 9.6 m for all the range of operation, and particularly with a single pump in operation, at a flow around 178 l/s. The pumps motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 80 K, degree of protection IP55, natural cooling with fan. The rated motor efficiency is according to IEC 60034-30 class high efficiency IE2. The pump constructor shall supply the motors: the proper operation of the whole pumping unit (pump + motor) is under the responsibility of the pump constructor.

The pumps are installed in a sump pit volume 0.65 m3, size 0.8 m x 0.8 m x 1.0 m depth, which is sized for 15 starts per hour of the motors, alternatively used for each pump. The dewatering pumps are interconnected and connected to a discharge pipe with ND 80 mm. For separated discharge of each pump, 2 non-return valves and 2 manual gate valves ND 80 mm are installed, with dismantling joints in between.

6.2.3.1 Water hammer protection system for SP-2A The water hammer protection system comprises of:  A pressure vessel 1,100 l ND 1,000 mm NP 10 bars, vertically installed, with an initial pressure of 1.9 bars. The air volume at dynamic pressure will be 0.4 m3;  1 air valve ND 60 mm, installed at high point at the branch 3KP1 (Pk 619). Air Inlet: for a depression of -0.2 bar, should the Air Valve bring an air flow of 0.15 m3/s and Air outlet: for overpressure of +0.2 bar, should the air valve discharge an air flow of 0.3 m3/s;  A compressor plus one for quicker start-up of the system and for spare;

 Ancillary pipes and equipment. The rated point of each compressor is 0.5 m3/h at 7 bars. These devices are interconnected with 2 non-return valves and 2 manual gate valves ND 25 mm and connected to the pressure vessel by pipes with ND 25 mm. The compressors’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. The motor power is selected taking into account the system efficiency and a security factor of 20%. The pressure vessel is equipped with a safety electric break-pressure valve with manual backup and a drain valve, all in ND 50 mm. The pressure vessel is equipped with a pressure gauge and for regulation purposes with 6 adjustable level sensors mounted on an external level visualization system by transparent tube and a magnetic visual float or equivalent system.

6.2.3.2 Water hammer protection system for SP-2B The water hammer protection system comprises of:  A pressure vessel 3,000 l ND 1,200 mm NP 10 bars, with an initial pressure of 0.4 bars. The air volume at dynamic pressure will be 0.7 m3;  2 air valves ND 60 mm special anti-shock (without abrupt closure) against surge alleviation, installed at high points at the branch PT11 (Pk 584 and Pk 1,451). Air Inlet: for a depression of -0.2 bar, should the Air Valve bring an air flow of 0.15 m3/s and Air outlet: for overpressure of +0.2 bar, should the air valve discharge an air flow of 0.3 m3/s;  A compressor plus one for quicker start-up of the system and for spare;  Ancillary pipes and equipment. The rated point of each compressor is 2.0 m3/h at 5.2 bars. These devices are interconnected with 2 non-return valves and 2 manual gate valves ND 25 mm and connected to the pressure vessel by pipes with ND 25 mm. The compressors’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. The motor power is selected taking into account the system efficiency and a security factor of 20%. The pressure vessel is equipped with a safety electric break-pressure valve with manual backup and a drain valve, all in ND 50 mm. The pressure vessel is equipped with a pressure gauge and for regulation purposes with 6 adjustable level sensors mounted on an external level visualization system by transparent tube and a magnetic visual float or equivalent system.

6.2.3.3 Water hammer protection system for SP-2C

The water hammer protection system comprises of:

 A pressure vessel 2,000 l ND 1,200 mm NP 10 bars, with an initial pressure of 0.2 bars. The air volume at dynamic pressure will be 0.6 m3;  A by-pass ND 350 mm NP 10 bars between suction pipe and discharge pipe of pumping station, for protect the irrigation network situated under the pressure vessel;  A compressor plus one for quicker start-up of the system and for spare;  Ancillary pipes and equipment. The rated point of each compressor is 1.0 m3/h at 3.1 bars. These devices are interconnected with 2 non-return valves and 2 manual gate valves ND 25 mm and connected to the pressure vessel by pipes with ND 25 mm. The compressors’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. The motor power is selected taking into account the system efficiency and a security factor of 20%. The pressure vessel is equipped with a safety electric break-pressure valve with manual backup and a drain valve, all in ND 50 mm. The pressure vessel is equipped with a pressure gauge and for regulation purposes with 6 adjustable level sensors mounted on an external level visualization system by transparent tube and a magnetic visual float or equivalent system.

The diameter of pipes upstream the pumps is chosen to have a velocity of 1.0 - 2.0 m/s and the diameter of pipes downstream the pumps is chosen to have a velocity of 2.0 - 3.0 m/s.

6.2.4.1 Pipes and fittings for SP-2A The pipes and fittings between the basin and the pumping station have the following characteristics: steel NP 10 bars ND 500 mm. The main pipes in the pumping room have the following characteristics:  Pipes and fittings upstream the pumps are of steel NP 10 bars ND 250 mm;  Asymmetrical cones upstream the pumps have an angle of 10°;  Symmetrical cones downstream the pumps have an angle of 10°;  Pipes and fittings downstream the pumps are of steel NP 10 bars ND 150 mm. The pipes and fittings between the pumping station and the flow-meter chamber have the following characteristics:  Discharge pipes and fittings are of steel NP 10 bars ND 150 mm;  Main pipe is of steel NP 10 bars ND 250 mm;  Pipe connection from the main pipe to the pressure vessel is of steel NP 10 bars ND 200 mm.

6.2.4.2 Pipes and fittings for SP-2B The common pipes and fittings with SP-2C between the basin and the pumping station have the following characteristics: steel NP 10 bars ND 600 mm. The main pipes in the pumping room have the following characteristics:  Pipes and fittings upstream the pumps are of steel NP 10 bars ND 350 mm;  Asymmetrical cones upstream the pumps have an angle of 10°;  Symmetrical cones downstream the pumps have an angle of 10°;  Pipes and fittings downstream the pumps are of steel NP 10 bars ND 250 mm. The pipes and fittings between the pumping station and the flow-meter chamber have the following characteristics:  Discharge pipes and fittings are of steel NP 10 bars ND 250 mm;  Main pipe is of steel NP 10 bars ND 350 mm;  Pipe connection from the main pipe to the pressure vessel is of steel NP 10 bars ND 300 mm.

6.2.4.3 Pipes and fittings for SP-2C The common pipes and fittings with SP-2B between the basin and the pumping station have the following characteristics: steel NP 10 bars ND 600 mm. The main pipes in the pumping room have the following characteristics:  Pipes and fittings upstream the pumps are of steel NP 10 bars ND 350 mm;  Asymmetrical cones upstream the pumps have an angle of 10°;  Symmetrical cones downstream the pumps have an angle of 10°;  Pipes and fittings downstream the pumps are of steel NP 10 bars ND 250 mm;  Pipes and fittings for the by-pass are of steel NP 10 bars ND 350 mm. The pipes and fittings between the pumping station and the flow-meter chamber have the following characteristics:  Discharge pipes and fittings are of steel NP 10 bars ND 250 mm;  Main pipe is of steel NP 10 bars ND 400 mm;  Pipe connection from the main pipe to the pressure vessel is of steel NP 10 bars ND 300 mm.

6.2.4.4 Ancillary Pipes and fittings The ancillary pipes in the pumping room have the following characteristics:  Pipes and fittings for the dewatering system are of steel NP 10 bars ND 80 mm;  Pipes and fittings for the water hammer protection system are of steel NP 10 bars ND 25 mm;  Pipes and fittings to drain the discharge pipes are of steel NP 10 bars ND 50 mm.

6.2.5 Valves

6.2.5.1 Valves for SP-2A The main valves in the pumping room have the following characteristics:  2 valves upstream the pumps are of gate valve type, manually driven NP 10 bars ND 250 mm. They are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 valves downstream the pumps are of gate valve type, electrically driven with manual backup system NP 10 bars ND 150 mm. They are fitted with visual position indicator, torque limiter and digital position switches “Open” and “Close”. The valves are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 non-return valves downstream the pumps are of flapper type, NP 10 bars ND 150 mm.  Valves for the water hammer protection system: o 1 gate valve, manually driven NP 10 bars ND 200 mm, for the pressure vessel. It is equipped with 1 dismantling joint, self-locked with flanged sleeves; o 1 break-pressure valve, electrically driven with manual backup NP 10 bars ND 50 mm, for the pressure vessel; o 1 drain valve manually driven NP 10 bars ND 50 mm, for the pressure vessel; o 2 non-return valves NP 10 bars ND 50 mm, for the compressors; o 2 gate valves, manually driven NP 10 bars ND 25 mm, for the compressors;

6.2.5.2 Valves for SP-2B The main valves in the pumping room have the following characteristics:  2 valves upstream the pumps are of gate valve type, manually driven NP 10 bars ND 350 mm. They are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 valves downstream the pumps are of gate valve type, electrically driven with manual backup system NP 10 bars ND 250 mm. They are fitted with visual position indicator, torque limiter and digital position switches “Open” and “Close”. The valves are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 non-return valves downstream the pumps are of flapper type, NP 10 bars ND 250 mm.  Valves for the water hammer protection system: o 1 gate valve, manually driven NP 10 bars ND 300 mm, for the pressure vessel. It is equipped with 1 dismantling joint, self-locked with flanged sleeves;

o 1 break-pressure valve, electrically driven with manual backup NP 10 bars ND 50 mm, for the pressure vessel; o 1 drain valve manually driven NP 10 bars ND 50 mm, for the pressure vessel; o 2 non-return valves NP 10 bars ND 50 mm, for the compressors; o 2 gate valves, manually driven NP 10 bars ND 25 mm, for the compressors;

6.2.5.3 Valves for SP-2C The main valves in the pumping room have the following characteristics:  2 valves upstream the pumps are of gate valve type, manually driven NP 10 bars ND 350 mm. They are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 valves downstream the pumps are of gate valve type, electrically driven with manual backup system NP 10 bars ND 250 mm. They are fitted with visual position indicator, torque limiter and digital position switches “Open” and “Close”. The valves are equipped with 2 dismantling joints, self-locked with flanged sleeves;  2 non-return valves downstream the pumps are of flapper type, NP 10 bars ND 250 mm.  2 valves for the by-pass are of gate valve type, manually driven NP 10 bars ND 350 mm;  1 non-return valve for the by-pass is of flapper type, NP 10 bars ND 350 mm. It is equipped with 1 dismantling joints, self-locked with flanged sleeves;  Valves for the water hammer protection system: o 1 gate valve, manually driven NP 10 bars ND 300 mm, for the pressure vessel. It is equipped with 1 dismantling joint, self-locked with flanged sleeves; o 1 break-pressure valve, electrically driven with manual backup NP 10 bars ND 50 mm, for the pressure vessel; o 1 drain valve manually driven NP 10 bars ND 50 mm, for the pressure vessel; o 2 non-return valves NP 10 bars ND 50 mm, for the compressors; o 2 gate valves, manually driven NP 10 bars ND 25 mm, for the compressors;

6.2.5.4 Ancillary valves The ancillary valves in the pumping room have the following characteristics:  Valves for the dewatering system: o 2 non-return valves NP 10 bars ND 80 mm; o 2 gate valves, manually driven NP 10 bars ND 80 mm;  2 gate valves, manually driven NP 10 bars ND 50 mm, for discharge pipes drainage.

The overhead travelling crane with a hoist capacity of 2 ton shall be reconditioned during a mechanical and electrical overhaul in workshop. The wearing parts are to be replaced by new ones.

6.2.7 Ventilation

The capacity of the ventilation devices is calculated as all the efficiency losses of the motors are converted into heat and to limit de internal temperature elevation of 5 degrees compared with the external temperature.

6.2.7.1 Ventilation for SP-2A The efficiency losses are estimated at 7% of the required power of the motors i.e. 8 kW. The corresponding capacity of the ventilation system is 6,552 m3/h. The total ventilation of the pumping room is realised with 1 fan. The rated point of the fan is thereby 6,552 m3/h at 1 mbar, taking into account head losses of 50 Pa for each air inlet and outlet. The fan is of window type, vertically mounted. For standardisation purpose with SP- 2B the rated flow will be 7,371 m3/h. It is equipped with an external protection grid with inclined flaps, which can be closed in winter. The fans’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. An air inlet is provided across from each fan on the other side of the pumping room. It is sized for a maximum air speed in the effective area of the grid of 3 m/s, what gives 0.8 m2 per air inlet, taking into account a reduction factor of 20% between gross area and effective area. It is equipped with an external protection grid with inclined flaps, which can be closed in winter.

6.2.7.2 Ventilation for SP-2B The efficiency losses are estimated at 7% of the required power of the motors i.e. 8 kW. The corresponding capacity of the ventilation system is 7,371 m3/h.

The total ventilation of the pumping room is divided into 1 fan. The rated point of fan is thereby 7,371 m3/h at 1 mbar, taking into account head losses of 50 Pa for each air inlet and outlet. The fan is of window type, vertically mounted. It is equipped with an external protection grid with inclined flaps, which can be closed in winter. The fan’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. An air inlet is provided across from fan on the other side of the pumping room. It is sized for a maximum air speed in the effective area of the grid of 3 m/s, what gives 0.8 m2 per air inlet, taking into account a reduction factor of 20% between gross area and effective area. It is equipped with an external protection grid with inclined flaps, which can be closed in winter.

6.2.7.3 Ventilation for SP-2C The efficiency losses are estimated at 7% of the required power of the motors i.e. 7 kW. The corresponding capacity of the ventilation system is 5,733 m3/h. The total ventilation of the pumping room is realised with 1 fan. The rated point of the fan is thereby 5,733 m3/h at 1 mbar, taking into account head losses of 50 Pa for each air inlet and outlet. The fan is of window type, vertically mounted. It is equipped with an external protection grid with inclined flaps, which can be closed in winter. The fans’ motor is asynchronous, squirrel cage induction type, designed for three-phase 400 V-50 Hz voltage, insulation class F, temperature rise 70 K, degree of protection IP55. An air inlet is provided across from each fan on the other side of the pumping room. It is sized for a maximum air speed in the effective area of the grid of 3 m/s, what gives 0.6 m2 per air inlet, taking into account a reduction factor of 20% between gross area and effective area. It is equipped with an external protection grid with inclined flaps, which can be closed in winter.

6.3.1 Power supply

The pumping station SP-2 A, SP-2 B and SP-2 C shall be supplied by low voltage three- phase 400 V-50 Hz. The grounding system is TN-C-S according to IEC standard. These outdoor utilities are under the responsibility of the electric supply company.

For the purpose of the power requirement calculation, the average power of the main pumps’ motors is taken into account when all the pumps are operating together. It differs from the maximum power calculated in the “Pumping units” chapter as the unitary flow is much less with all the pumps operating together than with a single one. For SP-2A, the main pumps motor average consumption is 59 kW when all the pumps are operating together, taking into account a rated motor efficiency at 93%.

For SP-2B, the main pumps motor average consumption is 70 kW when all the pumps are operating together, taking into account a rated motor efficiency at 93%. For SP-2C, the main pumps motor average consumption is 52 kW when all the pumps are operating together, taking into account a rated motor efficiency at 93%.

The ancillary equipment requires 47 kW, including a safety margin of 15 kW for maintenance purposes. The total power requirement of the pumping station is thereby 411 kW.

The low voltage electrical switch- and control gears include power and control equipment to be clearly separated in the cabinets. They are equipped with safety features according international and national regulations and comprises of:  1 main switch- and controlgear comprising o 1 incoming unit and general protection for the 630 kVA incoming power supply; o 1 feeder unit for the switch- and control gear for ancillaries; o 6 motor starter units for the main pumps with variable frequency drive; o 1 automatic reactive power compensation unit for the pumping station;  1 switch- and control gear for ancillaries;  1 pumping station control gear (control panel) for automation, monitoring and manual control;  1 switch gear for the operation in the non-irrigation period comprising: o 1 incoming and protection unit for the 40 kVA power supply; o Power distribution for lighting and sockets; o Power distribution for the anti-condensation heaters; o Motor starters for the drainage pumps;  10 remote control panels IP 65 in the pumping room, for the main pumps, the drainage pumps and the compressors;  1 wall insulating switch for the crane, according to local safety regulation.

 The general incoming and protection switch gear comprises of (not limited to):

o 1 main circuit breaker 1,000 A for the main power incoming;

o 1 monitoring and protection device for input voltages and currents (voltage fluctuations, cuts and phase reversal, isolation defect, etc.);

o 1 multifunction data-logger: voltage, current, active and reactive power, power factor, frequency, peak values;

o 1 general surge protection;

o 1 circuit breaker 200 A for the automatic plant for reactive power compensation of 75 kVAR;

o 1 circuit breaker 80 A for the switch- and control gear for ancillaries;

o 1 busbar Cu 80x8 mm per phase, Icc = 28,1 kA;

o 1 ground bus;

o Heating, ventilation and lighting inside the switch gear, including control and protections.

 The front door of the general incoming and protection switch gear includes:

o 1 white LED indicating the presence of voltage from the main power incoming;

o 1 red LED indicating a default from input voltages and currents;

o 1 push-button "Default reset";

o 1 display of the data-logger;

o 1 socket 230 V + G 16 A, 1 socket three-phase 400 V + G 32 A, 1 socket 24 V;

o 1 emergency stop «punch» button fail-safe wired disposed according to the regulation. 6.3.5 Motor starter switch gear with Variable Frequency Drive for SP-2A

o 1 motor protection circuit breaker 160 A;

o 1 multifunction Motor Protection Relay (MPR) to protect the motor either with use of Variable Frequency Drive (VFD) or by direct starting (by-pass of the VFD) for:

- Overload; - Stator winding over-temperature; - Short Circuit; - Locked Rotor; - Too frequent start; - Unbalance/single phasing; - Phase reversal; - Under-voltage;

o 1 contactor 115 A;

o 1 double switch 115 A with mechanical interlock. This device enables to by-pass manually the Variable Frequency Drive in case of default and to operate the motor with direct starting with auxiliary contact to signal position to PLC;

o 1 Variable Frequency Drive (VFD) enabling to modify the motors speed from 60% et 100%;

o 1 double switch 115 A with mechanical interlock. This device enables to isolate the Variable Frequency Drive when using the by-pass;

o Control circuits comprises of relays and control voltage protections;

o Part of the busbar Cu 80x8 mm;

o Cable termination equipment;

o Part of the switchgear ground bus;

o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the motor starter switchboard includes:

o 1 ammeter with a selector switch 4-position “0 – Phase 1 – Phase 2 – Phase 3”, including current transformer;

o 1 red LED indicating a default from Motor Protection Relay (MPR);

o 1 red LED indicating a default from Variable Frequency Drive (VFD);

o 1 yellow LED indicating that the by-pass is operating;

o 1 potentiometer for the Variable Frequency Drive (VFD);

o 1 hour-meter;

o 1 selector switch 3-position "Manual - 0 - Auto" for the pumps’ operating mode;

6.3.6 Motor starter switch gear with Variable Frequency Drive for SP-2B

o 1 multifunction Motor Protection Relay (MPR) to protect the motor either with use of Variable Frequency Drive (VFD) or by direct starting (by-pass of the VFD) for: - Overload; - Stator winding over-temperature; - Short Circuit; - Locked Rotor; - Too frequent start; - Unbalance/single phasing; - Phase reversal; - Under-voltage;

o 1 hour-meter;

6.3.7 Motor starter switch gear with Variable Frequency Drive for SP-2C

o 1 multifunction Motor Protection Relay (MPR) to protect the motor either with use of Variable Frequency Drive (VFD) or by direct starting (by-pass of the VFD) for: - Overload; - Stator winding over-temperature; - Short Circuit; - Locked Rotor; - Too frequent start; - Unbalance/single phasing; - Phase reversal; - Under-voltage;

o 1 hour-meter;

 The switch- and control gear for ancillaries comprises of (not limited to):

o 1 main circuit breaker 63 A;

o 6 motor starter devices comprising motor protection circuit breaker and 2 reversing contactors for the main valves’ actuators;

o 6 motor starter devices comprising motor protection circuit breaker and 2 contactors for the compressors;

o 4 motor starter devices comprising motor protection circuit breaker and 2 contactors for the fans in the pumping room;

o 1 thermo-magnetic motor protection circuit breaker and 1 contactor for the fan in the electrical room;

o 1 circuit breaker for the command, automation and remote control switch- and control gear;

o Circuit breakers for the water hammer protection system valves’ actuators;

o 1 busbar Cu 25x4 mm per phase;

o 1 ground bus

o Heating, ventilation and lighting inside the cabinet, including control and protections.  The front door of the cabinet for ancillaries includes:

o 6 hour-meters for the compressors;

o 3 selector switch 3-position "Manual - 0 - Auto" for the water hammer protection systems’ operating mode;

o 6 blinking white LED indicating the main pumps’ valves are opening. The LED remain stationary when the valves are fully opened;

o 6 blinking white LED indicating the main pumps’ valves are closing. The LED remain stationary when the valves are fully closed;

o 6 red LED indicating a default from the main pumps’ valves;

o 6 selectors switch 3-position "Manual - 0 - Auto" for the main pumps’ valves’ operating mode;

o 4 green LED indicating the fans of pumping room are operating;

o 4 red LED indicating a default from the fans of pumping room;

o 4 selectors switch 3-position "Manual - 0 - Auto" for the fans’ operating mode of pumping room;

o 1 green LED indicating the fan of electrical room is operating;

o 1 red LED indicating a default from the fan of electrical room;

o 1 selector switch 3-position "Manual - 0 - Auto" for the fans’ operating mode of electrical room;

 The command, automation and remote control switch- and control gear comprises of (not limited to):

o 1 Programmable Logic Controller (PLC) for managing the automatic operation and safeties (manual operation is not dependent of the controller). This unit has the necessary digital and analogical input and output cards as well as memory to monitor and store vital data and communication cards ensuring dialogue with the Remote Terminal Unit (RTU);

o 1 Remote Terminal Unit (RTU) for SCADA purposes, with GSM telecommunication modem and antenna;

o The terminal blocks for connecting all the equipment to the Programmable Logic Controller (PLC);

o 1 Uninterruptible Power Supply (UPS) 50 Ah allocated to the Programmable Logic Controller (PLC), the Remote Terminal Unit (RTU) and the instrumentation;

o Arresters’ modules for the measuring equipment (power and signal), for the Programmable Logic Controller (PLC) and for the Remote Terminal Unit (RTU);

o 1 ground bus;

o Heating, ventilation and lighting inside the cabinet, including control and protections.

 The front door of the command, automation and remote control switch- and control gear includes:

o 1 white LED indicating the presence of main voltage;

o 1 white LED indicating the presence of voltage from the Uninterruptible Power Supply (UPS);

o 1 Human Machine Interface (HMI) for: - Visualization of alarms; - Visualization of sensors’ states and analogical measurements;

- Visualization and adjustment of control parameters: level thresholds, flow threshold, pressure thresholds, timers, etc.;

o 3 numerical indicator for the measured flow;

o 1 numerical indicator for the water level in the basin;

o 1 red LED indicating an alarm for low water level in the basin;

o 6 red LED indicating alarms for high and low pressure in the discharge main pipe;

o 1 red LED indicating a default from the Programmable Logic Controller (PLC);

o 1 red LED indicating a default from the Remote Terminal Unit (RTU);

o 1 red LED indicating a default from the Uninterruptible Power Supply (UPS);

6.3.10 Secondary input and protection switch gear

 The secondary incoming and protection switch gear comprises of (not limited to):

o 1 main circuit breaker 32 A for the secondary power incoming;

o 1 monitoring device for input voltages, currents and power, according to the requirements of the electrical supply company;

o 1 circuit breaker 25 A downstream the monitoring device.

 The lighting and sockets switch gear comprises of (not limited to):

o 1 main switch 32 A for connection to the switch- and control gear for ancillaries. This device enable to switch manually from the secondary power supply used in winter to the main power supply used during the irrigation period;

o 1 surge protection;

o 2 motor starter devices comprising motor protection circuit breaker 10 A and 2 contactors for the drainage pumps;

o 1 circuit breaker 6 A for the crane;

o Branch circuit breakers for the different sockets and lighting groups;

o Branch circuit breakers for anti-condensation resistors for the main motors and for the switch gears;

o Box with step-down transformer 220 / 36 V.  The front door of the lighting and sockets switch gear includes:

o 2 hour-meters for the drainage pumps;

o 1 selector switch 3-position "Manual - 0 - Auto" for the drainage pumps’ operating mode.

6.3.12 Remote control panels for the main pumps

 These panels are located in front of the main pumps and comprise of:

o 1 red LED indicating a default from motor or pump (bearings temperature);

o 1 red LED indicating a default from the switchgear;

o 1 push-button "Start" to start the pump;

o 1 push-button "Stop" to stop the pump;

o 1 blinking white LED indicating the main valve is opening. The LED remain stationary when the valve is fully opened;

o 1 blinking white LED indicating the main valve is closing. The LED remain stationary when the valve is fully closed;

o 1 red LED indicating a default from the main valve;

o 1 push-button "Open" to open the main valve;

o 1 push-button "Stop" to let the main valve partially opened (for first filling of the network by manual operation);

o 1 push-button "Close" to close the main valve;

 This panel is located near the drainage pumps and comprises:

o 2 push-buttons "Start" to start the pumps;

o 2 push-buttons "Stop" to stop the pumps;

 This panel is located near the compressors and comprises of:

o 2 push-buttons "Start" to start the compressors;

o 2 push-buttons "Stop" to stop the compressors;

o 1 push-button "Open" to open the valves;

o 1 push-button "Close" to close the valves;

 The instrumentation and metering devices at the pumping station SP1 have the following characteristics:

o 6 pressure sensor/transmitters with analogical signals installed on the discharge pipes of each pump, for pressure measurement. They deliver measurement values of the discharge pressure at each pump. These sensors/transmitters delivers 4-20 mA signal as input into the PLC;

o 6 pressure gauges downstream the pumps;

o 6 pressure gauges downstream the discharge gate valves;

o 1 double pressure switch with digital signals installed on the discharge main pipe of SP-2A, for pressure detection. It shall switch if the discharge pressure is too low or too high. The pressure for alarms transmission is 1 bar above and below the extremes values of the discharge curve shown on the pump diagram: - 83 m = 8.1 bars: high pressure alarm; - 57 m = 5.6 bars: low pressure alarm;

o 1 double pressure switch with digital signals installed on the discharge main pipe of SP-2B, for pressure detection. It shall switch if the discharge pressure is too low or too high. The pressure for alarms transmission is 1 bar above and below the extremes values of the discharge curve shown on the pump diagram: - 62 m = 6.1 bars: high pressure alarm; - 34 m = 3.3 bars: low pressure alarm;

o 1 double pressure switch with digital signals installed on the discharge main pipe of SP-2C, for pressure detection. It shall switch if the discharge pressure is too low or too high. The pressure for alarms transmission is 1 bar above and below the extremes values of the discharge curve shown on the pump diagram: - 39 m = 3.8 bars: high pressure alarm; - 2 m = 0.2 bars: low pressure alarm;

o 1 pressure sensor/transmitter with analogical signals installed on each discharge main pipe, for pressure measurement. It delivers measurement values of the discharge pressure at the pumping station outlet. The transmitter shall be installed in or near the manhole for local monitoring and shall deliver the information as 4- 20 mA for the PLC;

o 1 ultrasonic flow-meter with analogical signal installed in the manhole on each discharge main pipe, for water flow measurement and integration capability to count and store the data of water volumes taken from water basin and delivered to the irrigation network. The flow meter will be of a type and model approved for use in Moldova for billing purpose. It delivers measurement values of the discharge flow at the pumping station. The transmitter shall be installed in or near the manhole for local monitoring and shall deliver the information as 4-20 mA for the PLC. Two indicators for flow and volumes are installed: one in the manhole and the other on the front door of the automation switch gear;

o 6 conductive water level switches with digital signal installed in the drainage sump pit, for water level detection. They deliver 4 water regulation signals and alarm signals if the water level is too low or too high. The level for signal transmission is as follows: - - 0.10 m: high level alarm; - - 0.20 m: Start pump Nr. 2; - - 0.25 m: Start pump Nr. 1; - - 0.55 m: Stop pump Nr. 2; - - 0.60 m: Stop pump Nr. 1; - - 0.70 m: low level alarm;

o 6 conductive water level switches with digital signal installed in each pressure vessel, for water level detection. They deliver 4 water regulation signals and alarm signals if the water level is too low or too high. For SP-2A, the level for signal transmission is as follows from the bottom (for a vertical vessel height 1,600 mm): - 1.24 m: high level alarm; - 1.19 m: Start compressor Nr. 2; - 1.14 m: Start compressor Nr. 1; - 1.09 m: Stop compressor Nr. 2; - 1.04 m: Stop compressor Nr. 1; - 0.55 m: low level alarm; For SP-2B, the level for signal transmission is as follows from the bottom (for a vessel ND 1,200 mm): - 1.02 m: high level alarm; - 0.97 m: Start compressor Nr. 2; - 0.92 m: Start compressor Nr. 1; - 0.87 m: Stop compressor Nr. 2; - 0.82 m: Stop compressor Nr. 1; - 0.75 m: low level alarm; For SP-2C, the level for signal transmission is as follows from the bottom (for a vessel ND 1,200 mm): - 0.94 m: high level alarm; - 0.89 m: Start compressor Nr. 2; - 0.84 m: Start compressor Nr. 1; - 0.79 m: Stop compressor Nr. 2; - 0.74 m: Stop compressor Nr. 1; - 0.56 m: low level alarm;

o 3 temperature sensors with analogical signals, the first installed in the pumping room, the second in the electrical room and the third outside the building, for temperature measurement. They deliver measurement values in 4-20 mA to a transducer that allows converting the information of the temperature at each location.

6.4.2.1 Operating modes  The pumping station can be operated in 3 different modes:

o Local manual mode: through the remote control panels and the cabinet for ancillaries. This level of control is widespread. The control is performed by switches in general 3-positions "Manual - 0 - Auto", push buttons "Start" - "Stop" or "Open" - "Close" for equipment controlled by the PLC. The hard wire basic safety devices are active for this mode (protections of the motor protection relay, temperatures in the motor windings or pump bearings, starting frequency, etc.);

o Local automatic mode: command through the PLC Human Machine Interface (HMI). The pumping station can run fully automatically. This level enable to have an overview of the status of the equipment, of alarms, to visualize measured values;

o Remote control mode: no commands through the remote control centre are foreseen. The dispatching centre will have only monitoring and data processing and storage functions. Data will be displayed on a screen of the supervision computer. At this level will also be performed the functions of alarm management, editing, archiving, diagnostic and maintenance support.

6.4.2.2 Control philosophy The regulation of the pumping station is made according to the water flow and the pressure required by the irrigation devices. The flow/pressure equation of the network resulting from the hydraulic simulation is:  For SP-2A: H=0.0003xQ²+0.0071xQ+68.8;  For SP-2B: H=0.00016xQ²+0.0073xQ+45.7;  For SP-2C: H=0.00037xQ²+0.0039xQ+11.2. The number of operating pumps and the frequency drive of the motor will be determined to follow these network curves. The system is designed to supply water between 20% and 100% of the rated flow. The pumping station shall be stopped if the measured flow goes under 20%. The adjustable parameter below shall be adjusted at the HMI of the PLC. The status change of the different sensors must remain during 5 s (adjustable temporization for each sensor) before the PLC undertakes an action. The instruction for manual starting of pumping station operation is as follows:  Check that all relevant equipment (water hammer system, vacuum pump sytem, pumps, valves, electrical supply, instrumentation and control, etc. ) is available;  Assure that the selector switches of the pumps is in manual mode and of the other equipment is in automatic mode;  Assure that the discharge valve is closed;  Check that the water level measurement in the basin is not triggered with alarm signal for low level;

 Fill the main delivery pipe with water by starting one pump in manual mode (if it is not already filled). Some of the most distant hydrants have to be open. The gate valve downstream the operating pump has to be open at 25% to maintain a counter-pressure (monitored at the gauge) to create a head loss and enable a smooth filling;  Open a minimum of 20% of the hydrants;  Open completely the gate valve downstream the operating pump;  Switch the pump to automatic mode. The VFD shall automatically adjust its frequency to reach the set point corresponding to the flow after checking that the double pressure switch on the main delivery pipe indicates that the pipe is full of water;  The water hammer system starts in automatic mode: the compressors are operating until the beginning of the regulation phase (1st stop of all compressors indicating that the air raised the lower part of the pressure vessel);  The regulation phase of the pumps begins. The particular automatic control philosophy for the water hammer system is as follows:

o Assure that the selector switch of the water hammer system is in automatic mode;

o Check that the water level switch in the pressure vessel is not triggered with alarm signal for low water level;

o Select the compressor Nr. to operate according to the last compressor which was in operation: the other compressor is selected;

o Start the compressor;

o Wait until the water level switch to stop the compressor is triggered in the pressure vessel. If it is not triggered after 30 min (adjustable parameter), start the second compressor;

o Regulate the stop and start of the compressor according to the activation of the corresponding water level switches in the pressure vessel;

o When the compressor planned is not available (in "Manual" or "0" position or in default) the other available compressor shall start. The particular automatic control philosophy of starting a pump in automatic mode is as follows:

o Start the pump at minimum speed (i.e. 60% of the rated frequency) and increase the speed gradually;

o Increase the speed until the discharge pressure sensor of the pump delivers a measured value equal to the minimum pressure according to the equation of the network curve: - For SP-2A: 69 m = 6.8 bars, adjustable parameter; - For SP-2B: 44 m = 4.3 bars, adjustable parameter; - For SP-2C: 10 m = 1.0 bars, adjustable parameter;

o Begin the regulation phase: - According to the water flow measured by the flow-meter, accelerates or decelerates the frequency controlled drive to reach the pressure of the set point calculated with the flow/pressure equation. This pressure is measured by the pressure sensor of the discharge main pipe. The set point is calculated every 30 s (adjustable parameter) and implemented with the Proportional/Integral/Derivative function of the PLC (PID controller); - If the required pressure cannot be reached after 30 s (adjustable parameter) at the maximum frequency reduce the speed of the pump to the minimum frequency (i.e. 60% of the rated frequency) and start the other pump at the minimum frequency; - According to the water flow measured by the flow-meter, accelerates or decelerates the frequency drive of both pumps at the same speed to reach the pressure of the set point calculated with the flow/pressure equation; - If the required water flow is reduced to 55 l/s for SP-2A (adjustable parameter) or 90 l/s for SP-2B (adjustable parameter) or 160 l/s for SP-2C (adjustable parameter) , the first running pump will be stopped and the other shall be set to its maximum speed before decelerating to meet the pressure of the set point;

o A cool down time set for 10 min (adjustable parameter) will be used to ensure that the pump cools down after each stop prior to automatic restart based on the flow in the network. This can be by-passed by the operator if required by using the push-button "Default reset" on the motor starter switchboard;

o If the VFD is out of order, it can be manually by-passed using the double switches provided for this purpose. When the pump station will be switched in the automatic mode again a pump with VFD will be first selected and the following regulation phase will be implemented: - According to the water flow measured by the flow-meter, accelerates or decelerates the frequency drive to reach the pressure of the set point calculated with the flow/pressure equation. This pressure is measured by the pressure sensor of the discharge main pipe. The set point is calculated every 30 s (adjustable parameter) and implemented with the Proportional/Integral/Derivative function of the VFD (PID controller); - If the required pressure cannot be reached after 30 s (adjustable parameter) at the maximum frequency start the other pump; - Reduce the speed of the former pump to the minimum frequency (i.e. 60% of the rated frequency); - According to the water flow measured by the flow-meter, accelerates or decelerates the frequency drive of the pump to reach the pressure of the set point calculated with the flow/pressure equation; - If the required water flow is reduced to 55 l/s for SP-2A (adjustable parameter) or 90 l/s for SP-2B (adjustable parameter) or 160 l/s for SP-2C (adjustable parameter), the running pump with fixed speed will be stopped;  The sequence of stopping a pump is as follows:

o Stop the pump;

o Open the valve of the vacuum pipe for priming the pump. The particular automatic control philosophy for the drainage system is as follows:

o Check that the water level switch in the drainage sump pit is not triggered with alarm signal for low water level;

o Select the pump Nr. to operate according to the last pump which was in operation: the other pump is selected;

o Start the drainage pump when the corresponding water level switch is triggered;

o Start the second drainage pump when the corresponding water level switch is triggered;

o Regulate the stop and start of the 2 drainage pumps according to the activation of the corresponding water level switches;

o When the pump planned is not available (in "Manual" or "0" position or in default) the other available pump shall start. The automatic particular control philosophy for the ventilation system is as follows:

o Assure that the selector switch of the fan is in automatic mode;

o A fan is dedicated to 1 or 2 pumps;

o Start a fan when the following conditions are reached together: - One of the corresponding pumps is operating; - The temperature sensor in the pumping room indicates more than 25°C (adjustable parameter); - The temperature sensor in the pumping room indicates more than the temperature sensor outside the building;

o When the fan planned is not available (in "Manual" or "0" position or in default) another available fan shall start;  Stop a fan when one of the following conditions is reached:

o All the corresponding pumps are stopped;

o The temperature sensor in the pumping room indicates less than 20°C (adjustable parameter);

o The temperature sensor in the pumping room indicates less than the temperature sensor outside the building. 6.4.2.3 Processing failure and alarms

o In case of processed values out of their normal range, an alarm will be sent to the SCADA system: low level in the basin, flood in pumping room, high and low pressure in the main discharge pipe. The pumps will not start or will be stopped with a 30 s delay between each (adjustable parameter);

o In case of VFD failure, the double switches can be manually switched to the direct starting position. A global defect alarm for pump will be sent to the SCADA system;

o In case of failure of pump, dewatering pump and compressor, it will be stopped and the other standby similar equipment will automatically be started instead of the former one. A global defect alarm for the corresponding equipment will be sent to the SCADA system. If no standby equipment is available the pumps will be stopped with a 30 s delay between each (adjustable parameter);

o In case of any failure on other device, it will be stopped as well as further actions and an alarm will be sent to the SCADA system: global defect for pump and corresponding valves, for the vacuum system, for the drainage system, for the water hammer system, for the ventilation system. The pumps will be stopped with a 30 s delay between each (adjustable parameter);

o In case of total power failure of less than 1 s (adjustable parameter), the pumping station will restart automatically. If the power failure is of more than 1 s, all the equipment shall be stopped and the pumping station has to be restart by manual action as described in the instruction for manual starting of pump operation.

6.4.2.4 Processing data and curves  The PLC shall provide the following data and curves: