Kudawilachchiya is an ancient abandoned tank located inside Wilpaththu National Park. The tank lies within the Maha Wilachchiya Divisional Secretariat area in Anuradhapura District.
At present, ruins of a large earthen bund about 2.55 km long is visible. The maximum height of the bund is around 12.6 m and is breached at seven locations. The main breach is at Weli Ela, which is the main feeder stream of the tank. In addition to this earthen bund, remains of two Bisokotuwas built out of rock slabs which have been damaged recently by treasure hunters are visible. The Spillway has been built out of well-cut rock boulders. The ancient rip rap protection is seen along the upstream face of the dam. This rip rap is also made of rock cut into the shape of rectangles laid along the dam in approximately in horizontal layers. Another significant feature is that the rip rap protection made out of two horizontal layers forming a berm on the upstream face of the bund.
The tank has been built by King Wasabha, who was a great tank builder according to the historians. Another legend carried on by the old farmers around the area is that the tank had been the work of Princess Asokamala, the Queen of famous Prince, Saliya who was a son of King Dutugamunu. But there are no evidences for any of these legends.
This abandond historical reservoir is planned to be restored by the Irrigation Department keeping the historical value as it is for another hundreds of years. In this restoration the following components are significant.
Embankment
The earthen embankment will be restored with the recommendations of the comprehensive Archaeological Impact Assessment (AIA). The maximum height of dam will be 12.6m. The upstream slope of the earthen embankment will be 1 on 3 slope while the downstream slope will be 1 on 2.5. The dam will be protected by a rip rap on the upstream face. The downstream will be protected by turffing. The ancient bund is planned to be preserved with its important features such as rip rap of cut granite slabs, sluice structures and spill structures.
Feeder Canal
A feeder Canal of 3.50 Km long will be constructed from the tank up to Sada Sarana Wewa level crossing located in the Maha Willachchiya Left Bank canal to feed 320 hectares directly from Kuda Wilachchiya Tank instead of Maha Wilachchiya Tank. At the beginning of this canal there is a section with a deep cut for 400m and this section has been designed as a cut and cover section to avoid wild animals falling into the canal. The total (gross) Catchment Area of the proposed reservoir location was estimated to be around 184 km2.
|
Reservoir |
|
|
Location Details |
360734E, 131689N |
|
Full Supply Level (FSL) |
54.05m MSL |
|
High Flood Level (HFL) |
54.66 m MSL |
|
Bund Top Level (BTL) |
|
|
Sluice Sill Level |
50.90 m MSL |
|
Gross Storage |
|
|
Capacity at minimum operating level |
|
|
Project cost |
Rs. 6000 Millions |
|
Dam |
|
|
Length |
2.6 Km |
|
Top width (Minimum) |
5 m |
|
Maximum Height |
12.6 m |
|
Upstream slope |
1 on 3 |
|
Downstream slope |
1 on 2.5 |
|
Rip rap thickness |
600 mm |
|
Average boulder size |
220 – 450 |
|
Spillway |
|
|
Type |
Radial Gated |
|
Number of gates |
|
|
Size of gates |
6.0 m x 3.05 m |
|
Ogee crest level |
51.00m MSL |
|
Minimum discharge |
491.75 m3/sec |
|
Sluice |
|
|
Type |
Concrete tower type |
|
Sill level |
50.90m MSL |
|
Size of gates |
1.05 m x 1.45 m |
|
Design discharge |
1.2 m3/sec |
Benefits
- Supply of drinking water to 25,000 people in MahaWilachchiya DS Division.
- Increasing the Cropping Index of MahaWilachchiya Major irrigation scheme from 1.57 to 2.0.
- Providing water to wild life in the Wilpaththu National Park.
- Ensuring the environmental flow along Madaragam Aru which is flowing through the National Park. This would indirectly support ground water recharging.
- Improved health conditions of the people.
- Reduction of human elephant conflicts.
- Increasing the tourism potential.
Contact
Region Map
