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Aquatic Procedia 4 ( 2015 ) 365 – 372

INTERNATIONAL CONFERENCE ON WATER RESOURCES, COASTAL AND OCEAN ENGINEERING (ICWRCOE 2015) Post-Phailin Restoration of Gopalpur Port

R.Sundaravadivelua, *, S.Sakthivelb, P.K.Panigrahic and S.A.Sannasirajd

a,d Department of Ocean Engineering, Indian Institute of Technology Mardras,Chennai – 600 036, bOcean Engineering and Consultancy Private Limited (OECPL),Chennai – 600 028, India cExecutive Director, Gopalpur Port Limited (GPL), India

Abstract

The Very Severe Cyclonic Storm (VSCS), PHAILIN crossed and adjoining north Andhra Pradesh coast near Gopalpur in the evening of 12th October 2013 with a maximum sustained wind speed of nearly 215 Km/hr. The cyclone caused very heavy rainfall over Odisha leading to floods, and strong gale wind leading to large scale damage to gopalpur port under construction. The damage had occurred to Breakwater, Groynes, Berths, Dredger, Barges, Survey Boats, Electrical Lines, Boundary Walls, Admin Building and Site offices etc. Heavy siltation was found in the channel and harbour basin and washed out rock from breakwater was scattered in the harbour area. Various sunken objects both ferrous and non-ferrous are found above and below seabed. The berm breakwater without the primary armour has flattened with a width of about 120 m. The top level which was about 5 m above water level has been lowered by 8 m to 10 m i.e, 3 m to 5 m below water level. The major restoration work is to build the berm breakwater from 900 m to 1730 m on top of the flattened portion. The cost of restoration to pre- PHAILIN status of the port is estimated at Rs.190 Crores and the restoration period will be from Nov-2013 to August-2014. The details of survey and the restoration works are presented in this paper. © 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (©http://creativecommons.org/licenses/by-nc-nd/4.0/ 2015 The Authors. Published by Elsevier B.V.). Peer-review-review under under responsibility responsibility of organizing of organizing committee committee of ICWRCOE of ICWRCOE 2015 2015.

Keywords: Phailin; Gopalpur Port; Breakwater; Groynes

1. Introduction

Gopalpur is located along the in the Ganjam District of the eastern Indian state of Orissa. The Paradip and Vizhagapatnam ports are located at a distance of 160 km towards north and 260 km towards south,

* Corresponding author. E-mail address: [email protected]

2214-241X © 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of organizing committee of ICWRCOE 2015 doi: 10.1016/j.aqpro.2015.02.049 366 R. Sundaravadivelu et al. / Aquatic Procedia 4 ( 2015 ) 365 – 372

respectively. The all weather direct berthing port was opened to commercial traffic on 29th March 2013 with the following functional facilities such as South Breakwater built with core under armour for a length of 1730 m, Intermediate Breakwater with a length of 365 m, Multipurpose Berth of 150 m length and Dredging completed to 10 m CD (Chart Datum).

The breakwaters are designed as berm type breakwaters to efficiently utilize the quarry yield and to optimize the construction speed with the manpower expertise. In the early 1980’s, the berm breakwater concept was introduced for a wave protection of a runway extension in Unalaska, Alaska. Hall (1991) proposed a wide berm of one stone class, where the armour system was designed so that essentially 100% of the quarry was utilized. The influence of

grading on reshaping is found to be less if ratio of D85 to D15 is less than 3 (D85/D15 < 3). A similar conclusion was

drawn by Van der Meer (1992) based on the tests conducted on dynamically stable breakwaters with ratio of D85 to

D15 = 2.25 (D85/D15 = 2.25). An extensive research on stability of statically and dynamically berm breakwaters were described by Van Der Meer (1992) and Torum (1998). The effects on the seaward profile on wave height, period, storm duration, spectral shape, initial slope, rock size, rock shape and grading, water depth and angle of wave attack, were described in a qualitative way. Sigurdarsan et al. (2007) has detailed the design rules of Icelandic-type berm breakwaters.

2. Layout of Harbour

The lagoon harbour was serving as an anchorage port from 1990. In order to protect the entrance channel of lagoon harbour, pair of training walls as shown in Fig. 1 is built in 2010-2011. The north breakwater of sea harbour is located about 1200 m south of south training wall. The sea harbour consists of a north and south breakwater. The length of north breakwater is 435 m up to 7 m contour and the length of south breakwater is 2170 m up to 13 m contour. The south breakwater consists of about 750 m straight portion perpendicular to the shoreline up to 10 m water depth and the balance length of 1400 m between 10 m and 12.5 m contour. The head section is in a water depth of 13 m. The rubble mound breakwater is adopted for north breakwater and a berm breakwater is designed for south breakwater following PIANC standards (PIANC WG30, 2003).A physical model stability test has been performed in the wave flume facilities of Department of Ocean Engineering, IIT Madras. The influences of wave height, wave period, berm level and sea-ward slope on the stability of berm breakwater have been observed. The run-up was measured. The variation of damage level and relative run-up was found for different values of wave steepness and berm level measured from SWL (Vedharaman, 2013).

Fig. 1. Layout of Harbour Fig. 2. Nourishment using pipeline

The alongshore transport towards north (March to October) is estimated as 1.6 million cum and south (November to February) is 0.3 million cum. The construction of breakwater is likely to erode the coast on the north and hence a groyne field is proposed as shown in Fig. 1. The construction of breakwater started in Jan 2012. The north R. Sundaravadivelu et al. / Aquatic Procedia 4 ( 2015 ) 365 – 372 367 breakwater for a length of 365 m is completed in September 2012 and the south breakwater for a length of 1735 m was completed in October 2013 with core and under armour. The total quantity of stones of different gradation is 2.46 million tons. The construction of groyneno2 to groyne no 11 started simultaneously. The groyne no 1 was not built in order to allow laying of pipelines for artificial nourishment. The dredging in approach channel and entrance channel started in Feb 2013 and the total quantity of dredging up to September 2013 is 2.9 million cum out of which 1.3 million cum is nourished in the north. The nourishment is carried out by using pipelines laid along the shore from the harbour basin to the north near the proposed groyne 2. Nourishment using pipeline and dumping area are shown in Fig. 2 and Fig. 3. The All Weather Direct Berthing Port was opened to commercial traffic on 29th March 2013 with the following functional facilities as shown in Fig. 4.

x South Breakwater with a length of 1730 m x Intermediate Breakwater with a length of 365 m x Multipurpose Berth measuring 150 m x Dredging completed to 10 m CD (Chart Datum) x Support infrastructure like roads, stock yards, buildings, etc.

Fig. 3. Dumping area Fig. 4. Sea port facilities for commercial operation in march 2013

3. Cyclone Phailin

The Very Severe Cyclonic Storm (VSCS), PHAILIN crossed Odisha & adjoining north Andhra Pradesh coast near Gopalpur in the evening of 12th October 2013 with a maximum sustained wind speed of nearly 215 Km/hr. The cyclone caused very heavy rainfall over Odisha leading to floods, and strong gale wind leading to large scale structural damage. The super cyclone Phailin is equivalent to category 5 hurricane and during a period of 24 hours the wind speed increased from 83 km/hr to 213 km/hr. The induced storm surge is estimated between 2.3 m and 3 m. Due to this severe cyclonic storm huge damage has been occurred in the Gopalpur Port and the details are given below:

3.1. Breakwater and Groynes 3.1.1. South Breakwater

x The cyclone storm initiates the occurrence of huge long waves which damaged the partially constructed South Breakwater. x The entire length of South Breakwater constructed up to 1730 m was devastated. No armour/sub-armour stone were visible. Over a length of 900 m from the bend portion of the south breakwater no trace of breakwater is visible except occasionally during low tide period x Main breakwater with secondary armour slipped in to the sea side. 368 R. Sundaravadivelu et al. / Aquatic Procedia 4 ( 2015 ) 365 – 372

x After 900 m LS the stones were flattened and got slided along sea side and harbour side. x After 900 m (Turning bend) the core layer was not visible. The stretch from 900 m to 1735 m is likely to provide tranquility as a submerged breakwater. x The berm portion of the South Breakwater including wave wall is slipped and flattened due to cyclonic waves.

3.1.2. North Breakwater

x North breakwater 360 m was built. Root 25 m length, the stones in the top (1m layer) were washed out and the remaining length got flattened. x North breakwater had not experienced a total failure condition but the sub-armour layers were disrupted and slopes and round head flattened. x Core layer and Secondary Armour on top and sides are flattened out due to cyclonic storm waves hitting the breakwater.

3.1.3. Groynes

x All the Groynes are partially damaged and half of the built length of each was washed away. x All the 11 nos. of Groynes were flattened and partly washed out. x The filled sand (Shore Nourishment) in between the Gronyes has been scoured/eroded due to the cyclonic storm waves. x About 100 m wide nourished beach between Marine Police Station and Groynes got totally eroded due to North-Easterly storm surge.

3.2. Berthing Structures

x Pile muffs, Fender fascia pads and chains were damaged. x Roof sheets of Laboratory sheds, store sheds, labour camp, cement sheds are blown away and the equipment kept inside the sheds got damaged. x Batching plant, pile boring equipment, vibro hammer, EOT crane, diesel generator sets are damaged.

3.3. Dredging and Shore Nourishment

x Due to the cyclone the soil got deposited in the dredged area. x All the floating crafts secured before the cyclone in safe area was force beached and lying on the North and South ends of the Multipurpose Berth. x Fishery boats are submerged in the Turning circle area. x Due to the cyclonic storm winds the Cutter Suction Dredger OSL Dredger-3 is forcibly dragged to the shore on the north side of the Multipurpose Berth by damaging the spuds and other on board equipment’s.

3.4. Port Premises

x High mast Lighting Posts (2 No’s ) fell down and fully damaged including feeder pillars at the north side of the Multi-purpose Berth including foundation due to gale winds of cyclone. x Diesel Generator (50 KVA) at the South Breakwater near the transformer is overturned and damaged R. Sundaravadivelu et al. / Aquatic Procedia 4 ( 2015 ) 365 – 372 369

partly. x Diesel Generator (500 KVA) at the Multi-purpose Berth junction box and foundation partly damaged. x Entire Electrical Lines, LT lines including D.P Structures are damaged. x Boundary wall barbed wire fencing is damaged and poles fell down almost 70% of the length is affected. x Roof of the Central Store and Ware Housing sheds are damaged. x Port Navigation accessories procured are damaged due to falling of container.

3.5. Port Administration Buildings and Other Buildings

x Window glasses, Ceilings, accessories and office furniture are partly damaged/broken. x Wall Cracks were observed in most of the places. x Admin Building Boundary wall grills are collapsed. x Most of boundary wall posts are also damaged/broken. x Power Supply cables & wiring are damaged in Port Admin Building. x Staff Quarters sloped roofs are fully damaged. x Estate section Office Building and Security section office Roofs are fully damaged.

4. Survey and Investigation to assess the damage caused by Phailin

To identify and assess the extent of buried/sunken objects within the harbour channel and maneuvering areas, a specialized diagnostic investigation work was carried out. The survey essentially was aimed at to map the sunken/buried rock, barges, anchors, fishing boats and trawlers, siltation etc. so as to plan and implement the restoration methods. The survey comprised use of multi-beam, single beam for hydrography and position fixing, side scan sonar for mapping the breakwater foot print and mapping of scattered rock including any other sunken objects on the sea bed, shallow seismic survey to map the buried objects, magnetometer to locate the ferrous debris. The coverage area on the seafloor is dependent on the depth of the water, typically two to four times the water depth.

Vertical control, for the survey works for during 1st and 2nd mobilizations was established at one of the jetties from a levelled local bench mark (LBM). Bathymetry data as obtained from the Echo Sounder was corrected for heights of tide and are corrected to C.D (Chart Datum). The data was gridded at 1m x 1m in bins and was plotted on 5m x 5m grid for better readability. All the bathymetry data was resolved to 0.1m and plotted on a horizontal scale of 1:1000 and 1:2000 on the plan view and with a vertical scale of 1: 1000 along on the profile view.

Maximum water depth within the survey area: 15.02m at NE part of the survey area beyond the proposed SBW Minimum water depth within the survey area: -1.27m at NW corner along the high tide line near IBW

4.1. Seabed Morphology

A 100 kHz Side Scan Sonar Record revealed the following reflectivity patterns in the present survey area: x Type 1: Medium to High Reflectivity (Fine to Medium Grained Sandy Sediments) x Type 2: High Reflectivity (Rock Outcrops/ Boulders) Type 1 reflectivity is observed throughout the survey area in general whereas Type-2 reflectivity is observed at the NE corner of the survey area along the alignment of the breakwater.

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A few disconnected medium sized isolated rocks/boulder as observed as isolated incidents on the south-east side along the periphery of the turning circle. Some more similar rocks/boulders are found along the head portion (end) of the south breakwater. These are observed lying perpendicular in alignment to the above group, near the head portion of the south breakwater. These groups of rocks are clearly seemed to be originating from the disintegrated portion of the head portion. The crest and toe portion of the harbour side of the southern breakwater is clearly discernible in the side scan sonar record and the same is marked as individual lines. However it is observed that along the head portion where there seems to be some amount of disintegration along the toe area. Post Phailin status of harbour and channel area is shown in Fig. 5. South breakwater and Groynes are shown in Fig. 6 and Fig. 9. Breaking waves in south breakwater and slided shore nourishment are shown in Fig. 7 and Fig. 8. Cost of rehabilitation to Pre-Phailin status is given in Table 1.

Fig. 5. Post Phailin status of Harbour and Channel area

Table 1. Cost of Rehabilitation to Pre-Phailin status.

Description Area of Damage Cost of Damage Breakwaters and Groins Breakwater and groynes are flattened and some portions Rs.152 Crores washed out. Rock quantity required for restoration work 23 It is Contractor’s lakh Tonnes stone liability as per contract stipulations. Berth Fender frontal frame, chains, hooks and mooring rings Rs.8.5 Lakhs R. Sundaravadivelu et al. / Aquatic Procedia 4 ( 2015 ) 365 – 372 371

damaged Dredging Channel and berth pocket silted up. Rs.32 Crores (Removal/salvage of Total quantity of stone in navigational area 2,00,000 MT wrecks, washed of Stones Estimated siltation quantity 5 lakhs Tonnes cum and siltation dredging) Electrical Works Lighting poles, UG cables, LT line and sub-station panel Rs.3.12 Crores damaged. On shore works Residential, non-residential buildings, stock yards, roads and Rs.2.55 Crores others damaged severely Rs.37.76 Crores, Say Total cost excluding contractor’s liability Rs.38 Crores

Fig. 6. South Breakwater Fig. 7. Breaking waves in South Breakwater

Fig. 8. Shore Nourishment slided Fig. 9. Groynes

372 R. Sundaravadivelu et al. / Aquatic Procedia 4 ( 2015 ) 365 – 372

Fig. 10. Cross section at CH 910 m and 1000 m

Conclusions

The cyclone Phailin has severly damaged the berm breakwater since the primary armour layer was not placed. The cyclone has not caused significant erosion except near groyne 3. In order to restore the berm breakwater it is proposed to construct the new berm breakwater on top of the flattened submerged stones as core and toe mound.

All the Groynes were partially damaged and half of the built length of each was washed away. The artificially filled dredged sand (Shore Nourishment) in between the Groynes had been scoured or eroded due to the cyclonic storm waves. In order to protect the northern shoreline post Phailin, artificial nourishment of 270,000 cum dredged from the lagoon area from November to February 2014 has been carried out. It is recommended to simultaneously build the groynes and artificially nourish using dredged sand of about 1.5 million cubic meter as the littoral drift is of the order of 1.5 million cubic meter.

Due to the cyclone, the soil got deposited in the dredged area. All the floating crafts secured before the cyclone in safe area was force beached on the North and South ends of the Multipurpose Berth. In order to identify the breakwater foot print and mapping of scattered rock including any other sunken objects on the sea bed, multi- beam survey had been carried out. The side scan sonar and shallow seismic survey was carried out to map the buried objects and magnetometer to locate the ferrous debris.

References Murty, P.L.N.,Sandhya, K.G.,Bhaskaran, P.K., Jose, F.,Gayathri, R., Balakrishnan Nair, T.M., Srinivasa Kumar, T. And Shenoi, S.S.C. 2014. A coupled hydrodynamic modeling system for PHAILIN cyclone in the Bay of Bengal. Coastal Engineering 93, 71-81. PIANC WG40, 2003. State of the art of designing and constructing berm breakwaters. Report of working group 40, Maritime Navigation Commission. Vedharaman, V.J. 2013. Physical modelling of stability of berm type breakwater. M.Tech. thesis, Department of Ocean Engineering, IIT Madras. Hall, K.R. 1991. A study of the stability of dynamically stable breakwaters. Canadian Journal of Civil Engineering 18, 916-925. Sigurdarson, S., et al. 2007. Optimum safety levels and design rules for the Icelandic-type berm breakwater. Coastal Structures, ASCE. Torum, A. 1998. On the stability of berm breakwaters. Proc. 26th International Conference on Coastal Engineering 2, 1435-1448. Van der Meer, J.W. 1992. Stability of the seaward slope of berm breakwaters. Coastal Engineering 205-304.