ANDAL ERI WATERSHED ANALYSIS AND LAKE REJUVENATION

Nansei Research Foundation in collaboration with Seethanam Foundation from Ambalapattu Panchayat of Thanjavur district undertook a detailed topological cum groundwater scenario
analysis was performed during the field visits and the ideal design for restoration or rejuvenation of Aandal Lake is given below. This is considering scientific principles of optimum design to maximize the use of available water in the groundwater of the region helping the farmers of Ambalapattu panchayat.

The lake area was divided into 8 plots based on the depth of the ground level from the Full Tank Level (FTL). Initially, the layout design proposed 30 islands with diameters ranging between 40 to 60 ft. However, this was revised to include 20 islands, as depicted in the image below.

Importance of Islands in the Design:

Wind Barrier and Evaporation Reduction:
The islands are strategically spaced to act as a natural wind barrier, significantly reducing water evaporation losses.

Ecological Zone Creation:
Tree plantations on the islands will provide habitats for biodiversity, fostering an ecological balance.

Cost Efficiency:
By reducing the amount of soil excavated from the lake area, the number of islands helps lower overall project costs.

Rejuvenation Plan and Recommendations:

It is recommended to rejuvenate Aandal Lake with a budget of ₹2.26 Crore to enhance its water-holding capacity by 2.8 times, increasing it from the current 1.66 Lakh Cubic Meters to approximately 4.66 Lakh Cubic Meters.

This recommendation is based on a comprehensive scientific hydrogeological assessment, considering factors such as water availability for the lake and the region's groundwater recharge potential.