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Furthermore, by controlling the entry of sea water into the Vadamarachchi and Upparu lagoons using monsoon waters and connecting the Elephant Pass lagoon with a canal bringing fresh water, the salinity of lagoons will disappear and eventually the wells and the agricultural lands would become usable.
The project was first proposed 350 years ago by the Dutch, and construction work on the ‘A River for Jaffna’ project commenced in 1947. The bulk of the work was completed in the 1950s, but unfortunately was damaged due to floods and became unusable.
Geography
The Jaffna Peninsula has an area of about 1,000 sq km, is relatively flat and has no rivers. For the recharge of the water table in the underlying limestone aquifer, it depends on the annual rainfall of about 1270 mm, of which about 87% falls from October to December during the NE monsoon.
In the past, water was drawn from the wells by hand, but from the 1950s, excessive extraction with mechanical pumps lowered the fresh water levels in the limestone aquifer, resulting in sea water intrusion into the wells, as no part of Jaffna is more than 15 km from sea. Now about 30% of the wells are saline.
Elephant Pass lagoon
South of the peninsula, the relatively shallow sea-water Elephant Pass lagoon has a surface area of about 77 sq.km. During the NE monsoon, rain water from the mainland Vanni from an area of about 940 sq.km flows into the lagoon through Kanakarayan Aru and three smaller streams.
With water supplied from the Vanni by these streams into the Elephant Pass lagoon, surplus water gets discharged to the sea through the eastern 
end at Chundikulam and western end through the Elephant Pass Bridge.
Vadamarachchi and Upparu lagoons in the Jaffna peninsula, with surface areas of about 77 and 26 sq. km respectively, cover 10% of the peninsula’s land. These lagoons are connected to the sea and are fed by the NE monsoon.
‘A River for Jaffna’
Eng. S. Arumugam proposed the ‘A River for Jaffna’ plan in 1954, to utilise monsoon rain water from the mainland streams running to waste through the Elephant Pass lagoon, for the benefit of Jaffna.
Key points of the scheme and details of work done are as follows:
At the northern end of the Vadamarachchi lagoon joining the sea, the Thondamanaru Barrage was built, starting in 1947 and completed in 1953, to convert the Vadamarachchi lagoon to fresh water, fed with rain water from its 300 sq km catchment area.
In 1955, the Arialai barrage was built where the Upparu lagoon connects to the sea, to make Upparu a fresh water lagoon, fed by rain water from its 220 sq km catchment area.
Openings in the road and rail bridges in Elephant Pass causeway at the western end of Elephant Pass lagoon was closed to prevent fresh water escaping to the sea.
A bund was built in the 1950s, at the eastern end of Elephant Pass lagoon at Chundikulam to isolate Elephant Pass lagoon from the sea, with a spillway provided to discharge excess flood water to the sea.
With water from the Kanakarayan Aru, Elephant Pass lagoon gradually became a fresh water lagoon, but unfortunately the Chundikulam bund was breached by heavy floods, allowing sea water inflow to Elephant Pass lagoon again.
A 12 metre wide, four km long channel, called the Mulliyan Link Channel, was proposed from the north eastern side of the Elephant Pass lagoon to convey fresh water from the Elephant Pass lagoon to the Vadamarachchi lagoon at its southern end, including regulatory gates to control the flow. About 80% of channel was completed in the 1960s, after which funds ran out and the work was never completed.
A link channel was built between Vadamarachchi and Upparu lagoons so that fresh water from Elephant Pass lagoon can be supplied to Upparu lagoon via Vadamarachchi lagoon.
Fresh water lagoons
In the brief period that Vadamarachchi and Upparu were fresh water lagoons, the benefits to the peninsula were noticeable and many saline wells became potable water wells, thus establishing the rationale of the ‘A River for Jaffna’ project.
The scheme was thus only partially completed in the 1960s and the key Mulliyan link channel to convey fresh water from Elephant Pass lagoon to Vadamarachchi lagoon was never completed. By year 2000, gates on Thondamannaru and Upparu were decayed and no longer watertight, resulting in sea water entering the Vadamarachchi and Upparu lagoons.
Agricultural use
About 8,000 ha. of land are cultivated with paddy in the Jaffna Peninsula and this cultivation is entirely rain fed. Give the dependence on rain, the yield per acre in Jaffna is very poor and is only about one-third of national average.
If Vadamarachchi and Upparu lagoons become fresh water lakes, the water table and water quality in the wells will improve, and with lift irrigation could irrigate these paddy fields without depending solely on the rain.
About 4,400 ha of land bordering the Vadamarachchi and Upparu lagoons are uncultivable at present as they are saline. When these become fresh water lagoons, after the salt is leached from the soil, it will be possible to cultivate this 4,400 ha with cash crops and paddy.
There will be a dramatic improvement in the water quality of the 30% of the Jaffna wells which are now saline. In many cases water will become suitable for domestic use and agriculture, increasing the acreage under cultivation.
In the existing wells, it will be possible to increase the amount of daily pumping without the water becoming saline, thus increasing agricultural cultivation and livestock production.
Work needed to complete the scheme
Step 1: Recondition of Thondamanaru Barrage.
Work has been already completed by State Engineering Corporation in 2008, on the instructions of President Rajapaksa.
Step 2: Recondition Arialai Barrage
Repair and replacing of perished planked bays and replacement of screw operated gates has been attended. Also repair breaches in separation bund between Vadamarachchi and Upparu lagoons.
Step 3: Complete Spill cum Causeway at Chundikulam
At the eastern end of Elephant Pass lagoon, when 2100 metre long spill cum causeway and 1,400 metre long bund is completed, Elephant Pass lagoon will become a fresh water lagoon. To be done.
Step 4: Complete Mulliyan Link Channel
When Elephant Pass lagoon becomes progressively low in salt content, assisted with rains from NE monsoon and with passage of time, with the completion of 12 metre wide, four km long Mulliyan Link Channel, will allow Elephant Pass lagoon waters to be diverted to Vadamarachchi and Upparu lagoons. To be attended.
Balance works described above is expected to cost around Rs. 1,200 million.
Proposed Water Supply for Jaffna project – NWS&DB
Meanwhile, without reference to the ‘A River for Jaffna’ project, the National Water Supply and Drainage Board had prepared a Jaffna Water Supply and Sanitation project. A loan of US$ 80 million – equivalent to Rs. 10 billion – has been negotiated with ADB, with a local component of Rs. 3 billion making Rs. 13 billion total.
The source of water proposed is Iranamadu tank and water to be pumped about 60 km to Jaffna from Paranthan. This will draw down water from Iranamadu Tank, thus further reducing the acreage of cultivated land, which is presently said to supply only about 30% of the available acreage.
On the other hand, the ‘A River for Jaffna’ project at a fraction of the cost, utilises only the overflow water from Iranamadu, downstream rainfall and other streams flowing into Elephant Pass lagoon and is taken by gravity to Jaffna, without pumping.
An expatriate Tamil engineer suggested: “If ‘A River for Jaffna’ is completed, the Jaffna underground aquifer will be recharged with sufficient fresh water for extraction for the Jaffna Water Supply Scheme without having to run a pipeline all the way to Iranamadu.”
If the proposed Water Supply for Jaffna project be revised to incorporate positive reactions of ‘A River for Jaffna’ project, the water requirement of Jaffna Peninsula would be appreciably reduced and much of this colossal sum of money can be saved.
History
The earliest proposal to improve fresh water in Jaffna was made 350 years ago by Dutch Captain Hendrile van Reedle who suggested, “A dike to contain the sea at 
Condemannaer and Navacolii, with sluices to claim the rain water and a canal to the salt pains at Nieweli would create more useful land.”
Twyneham (GA Jaffna) 1879 – Proposed dams would prevent entry of salt water and convert Elephant Pass Lagoon, Vadamarachchi lagoon and Upparu lagoon to freshwater reservoirs.
Horseburg (GA Jaffna) 1916 – Suggested experimental implementation of above proposal.
Webb (Divisional Irrigation Engineer) in the 1940s produced detailed plans for two barrages at Thondamannar (built in 1953) and at Ariyalai (built in 1955).
Eng. S. Arumugam published ‘A River for Jaffna’ in 1954 which became known as the Arumugam plan.
In January 1983, a report was submitted to President J.R. Jayewardene urging completion of the scheme. The President directed his officials in May 1983 to implement the scheme. But due to the July 1983 disturbances and its aftermath implementation did not happen.
Eng. S. Arumugam’s son Eng. Thiru Arumugam provided a synopsis of the plan for a Pugwash workshop on ‘Learning from Ancient Hydraulic Civilisations to Combat Climate Change,’ Colombo 2007.
At the Annual Sessions of the Institution of Engineers, Sri Lanka, (IESL) in 2007 a resolution was passed recommending to Government to undertake early implementation of the project.
When the resolution was submitted to President Mahinda Rajapaksa, a sum of Rs. 100 million was released for the restoration of Thondamannar barrage and this work was completed by State Engineering Corporation in 2008, repair and replacement of perished planked bays and replacement of the screw operated gates, while the war was still on.
Current situation
Step 1, the reconditioned Thondamanaru Barrage and Step 2, reconditioned Arialai Barrage on Kandy-Jaffna Highway has already been carried out. With the result both Vadamarachchi and Upparu lagoons have noticed reduction in salinity and some farmers bordering the lagoons have begun cultivation.
The reduction in salinity in the two lagoons has brought unexpected problems too. The brackish waters were prolific breeding grounds for prawns and crabs, which were caught by the local fishermen for a living and now their livelihood is being challenged.
Already animosities have arisen between the promoters of the project and the fishing community, which are bound to increase.
Seminar
Discussion after the speeches at the seminar showed different opinions amongst the senior engineers from Jaffna, who themselves have experimented with the salinity problem and each had a different opinion. But none of them had given thought to the problems of the fishing community. Are the high caste Tamil community not concerned of the plight of the low-caste fishermen?
Environmental issues
The conversion of Vadamarachchi and Upparu lagoons as well as the Elephant Pass lagoon into freshwater is a massive environmental issue and resulting changes need to be properly addressed. There are hundreds of fisher families who live along the borders of the three lagoons and depend on the saline water where fish, prawns and crabs thrive.
Jaffna is famous for its huge prawns and crabs and any changes to salinity levels will affect the growth of prawns and crabs. There had been suggestions of introducing freshwater prawns into the salinity-changing lagoons. But has any research being carried out over the issue? Can the newly -introduced prawns and crabs give the same yields to the fishermen?
Anyway, no funding agency will provide funds to a project which has neglected environmental issues.
Silver lining over the horizon
The much-delayed ‘A River for Jaffna’ project is expected to get a fresh boost with the new Northern Provincial Council to be formed shortly. They would certainly give priority to the long-delayed project. The numerous senior engineers who promote the project with different views need to be brought to one voice. The minor proposals they talk of could be implemented later after the main project.
All rivers and waterways in the Northern Province come under the Provincial Irrigation Department (PID) and the Central Government has no authority over the matter. Under the Provincial Councils Act, only the rivers crossing two or more provinces come under the Central Irrigation Department. But does the PID have experienced and knowledgeable engineers to handle a project of such magnitude?
It is known that the LTTE did not allow young engineers from the north to travel south of Vavuniya. So the PID will have to get help from the Central Irrigation Department, which has proved itself during recent years, for design and implementation of the ‘A River for Jaffna’ project, including addressing environmental issues.
(The writer is a Chartered Civil Engineer graduated from Peradeniya University and has been employed in Sri Lanka and abroad. He was General Manager of State Engineering Corporation of Sri Lanka. He can be contacted on [email protected].)
