Rosmincol Bulk Water Supply to Swartruggens and Mazista
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KGETLENGRIVIER LOCAL MUNICIPALITY Project No: MwB 20070 Rosmincol Bulk Water Supply to Swartruggens and Mazista TECHNICAL FEASIBILITY AND PRELIMINARY DESIGN REPORT Phase 2a and 2b (DWS Guidelines) Report 2 & 3 November 2016 PREPARED FOR: ON BEHALF OF PREPARED BY: MAGALIES WATER KGETLENGRIVIER LM MwB Consulting Engineers 38 Heystek Street P O BOX 66 204 Beyers Naude Drive Rustenburg Koster Rustenburg 0299 0348 0300 Contact Person: Contact Person: Contact Person: Mr Mahlomola Mehlo Mr Ben Shikwambana Mr Marx Jordaan Tel: 014 597 4636 Tel: 014 543 2004 Tel: 014 592 8504 Fax: 014 597 4635 Fax: 014 543 2005 Fax: 014 592 2024 Email: Email: Email: [email protected] [email protected] [email protected] FORM OF APPROVAL PROJECT NAME: Rosmincol Bulk Water Supply to Swartruggens and Mazista PREPARED BY: MwB Consulting Engineers (Pty) Ltd. CLIENT: Magalies Water / Kgetlengrivier Local Municipality REPORT STATUS: Technical Feasibility and Preliminary Design Report DATE: November 2016 DISCLAIMER: This report has been prepared on behalf of Magalies Water / Kgetlengrivier LM, and for the exclusive use of Magalies Water / Kgetlengrivier LM, and is subject to and issued in accordance with the agreement between Magalies Water, Kgetlengrivier LM and MwB Consulting Engineers (Pty) Ltd. MwB Consulting Engineers (Pty) Ltd accepts no liability or responsibility whatsoever for it in respect of any use of or reliance upon this report by any third party. Copying this report without the permission of Magalies Water / Kgetlengrivier LM and/or MwB Consulting Engineers (Pty) Ltd is not permitted. Consultant approval: Name Mr. AM Jordaan (Pr Eng), (Pr CMP) Signature ___________________________________ Date ___________________________________ Name Client approval: Mr Mahlomola Mehlo Signature ___________________________________ Date ___________________________________ Client approval: Name Mr Witsman Signature ___________________________________ Date ___________________________________ Rosmincol Bulk Water Supply to Swartruggens and Mazista Technical Feasibility and Preliminary Design Report EXECUTIVE SUMMARY Swartruggens and Borolelo are supplied with potable water from the Swartruggens Water Treatment Plant (WTP). Raw water to this plant is supplied from the Swartruggens Dam and augmented from a spring source in the Polkadraai Spruit. The safe yield of the Swartruggens Dam is not able to meet the current requirements of the community and it runs dry during virtually every dry season, every year. The Polkadraai Spruit water source is unreliable. It runs dry in periods of extreme draught and farmers are contesting the water use. The Swartruggens Dam is silted up and constructed in an area where slate or mudstone dominates the geology of the basin. The dam regularly runs dry, normally towards the end of the dry season, just before the rainy season. The safe yield of the dam is smaller than the demand on the dam. During normal rainfall seasons the dam overflows for extended periods. The safe yield can therefore be increased by increasing the storage volume of the dam. The process of constructing more storage can be regarded as a long-term solution whereas the augmentation of supply into town from boreholes could be a medium term solution that can be constructed in a couple of months. The projected water demand for 2030 of the greater Swartruggens is 5 M ℓ/d. Over the years more than 34 boreholes were drilled, and some were developed, for water supply into town. Currently, only two of these remained and are still in production. Reports clearly state that it is not viable to explore for ground water sources in and around the town. The following alternative water sources have been identified to augment the supply into the greater Swartruggens. These are: • Importing raw water from the Lindleyspoort Dam; • Increasing the storage of the Swartruggens Dam to increase the safe yield; • Importing water from the dolomite areas some 40 km to the south of town ; and • Re-using treated sewage effluent. The Department of Water and Sanitation is considering funding this project through the emergency funds as a measure to address the immediate supply to the town. Page | i Rosmincol Bulk Water Supply to Swartruggens and Mazista Technical Feasibility and Preliminary Design Report The following deliverables are envisaged: The initial planning phase for a technical feasibility study where the need was 1 Scoping report Complete identified and all the relevant background information documented and assessed. This report describes the proposed technical intervention and documents the analysis Technical and methodology on how the proposed solution was determined. An option analysis 2 Current report feasibility report is also included for larger projects particularly for water resource augmentation related projects. This is the preliminary design of the bulk infrastructure scheme where various Preliminary 3 technical options are identified and evaluated. The deliverable from this study will Current report design report include a budget estimate for the development of the project. Page | ii Rosmincol Bulk Water Supply to Swartruggens and Mazista Technical Feasibility and Preliminary Design Report Rosmincol Bulk Water Supply to Swartruggens and Mazista Table of Contents ABBREVIATIONS ................................................................................................................................ vi 1 INTRODUCTION ..................................................................................................................... 7 2 METHODOLOGY .................................................................................................................... 8 3 DEMAND ANALYSIS ............................................................................................................. 10 3.1 Existing Demand Analysis ................................................................................................... 10 3.2 Water Inefficiencies and Wastage ...................................................................................... 11 3.3 Future Demand Projections ................................................................................................ 11 4 WATER CONSERVATION / WATER DEMAND MANAGEMENT ........................................ 13 4.1 Impact on Planning of the Project ....................................................................................... 13 4.2 Impact on the Economic / Financial Viability of Project ...................................................... 13 5 WATER QUALITY INVESTIGATION .................................................................................... 14 6 ANALYSIS OF EXISTING INFRASTRUCTURE ................................................................... 16 7 OPTIONS ANALYSIS ............................................................................................................ 16 7.1 Source Options Identified .................................................................................................... 16 7.2 Identified pipe routes ........................................................................................................... 17 8 FurthEr research and investigationS ..................................................................................... 18 8.1 Electricity supply ................................................................................................................. 18 8.2 Borehole exploratory yield testing ....................................................................................... 19 8.2.1 General .............................................................................................................................. 19 8.2.2 Hydrogeological investigation during November 2016...................................................... 19 8.2.3 Potential groundwater areas / zones: ............................................................................... 20 8.3 Land Ownership and Servitudes ......................................................................................... 22 8.4 Geological investigations .................................................................................................... 22 8.4.1 General Perimeters ........................................................................................................... 22 8.4.2 Geological setting .............................................................................................................. 23 8.4.3 Site walk-over survey ........................................................................................................ 24 9 Hydraulic analysis .................................................................................................................. 27 9.1 Pressure Reducing Valve .................................................................................................... 29 Page | iii Rosmincol Bulk Water Supply to Swartruggens and Mazista Technical Feasibility and Preliminary Design Report 9.2 Hydraulic Summary ............................................................................................................. 30 10 water use licence application ................................................................................................. 31 11 eia approval process .............................................................................................................. 32 12 project implimentaTion plan ..................................................................................................