TR-122 : Performance evaluation of percolation tanks

Abstract

Percolation ponds are small water harvesting structures constructed across small natural streams and water courses to collect and impound the surface runoff during monsoons so as to facilitate the impounded water to infiltrate into the land and percolate through the substrata thereby recharging the groundwater reservoir. Construction of percolation ponds conserves the runoff and conveys it to the groundwater reservoir steadily. The yield of wells at the downstream side of the pond increases significantly. The zone of influence depends upon the slope of water spread area of the pond. After the construction of pond, the yield of water increases phenomenally for every unit of rainfall. Permeability of the soil is primarily responsible for the rate of groundwater recharge from the pond. Recuperation of water in the well after construction of pond is rapid besides increase in quantum. This is aided by the depth of storage in the pond. The pond helps harnessing the runoff efficiently through proper management. The pond exerts a cooling affect on the climate and this microclimate results in economy in water use by crops in the zone.

The percolation ponds are designed and constructed with the presently available hydrologic guidelines and norms. These ponds are serving well in the artificial recharge of the ground water reservoir and the benefit of these structures have been well appreciated by the farming community of well commands. However there is a scope for further refinement in the hydrologic norms and guidelines for the design and construction of percolation ponds.

The present study discusses about planning, design, construction, maintenance, socio-economic aspects of constructing percolation ponds. The report also discusses about the monitoring and performance evaluation of the percolation ponds.