Percolation Ponds
PERCOLATION PONDS • A percolation pond is a small water storage structure constructed across a natural stream or water course to harvest the runoff from the catchment and impound for longer time to facilitate percolation of impounded water into the soil substrata both vertically and laterally, thereby recharging ground water storage in the zone of influence of pond.
• It is formed by the construction of earthen bund with a surplus weir across the stream at a suitable location upstream of the zone which needs to be recharged.
Performance_Evaluation_of_Percolation_Po nds_for_Artificial_Recharge.pdf
Usage • It stores water for livestock and recharges the groundwater. • It is constructed by excavating a depression, forming a small reservoir or by constructing an embankment in a natural ravine or gully to form an impounded type of reservoir.
Recharge • The construction of percolation pond allows infiltration of the storage through the top soil to percolate deep to the ground water storage. This quantity of water reaching the ground water storage is known as recharge.
Capacity • The capacity of these ponds or tanks varies from 0.3 to 0.5 mcft (10 000 - 15 000 m3). • Normally 2 or 3 fillings are expected in a year (season) and hence the amount of water available in one year in such a tank is about 1 mcft to 1.5 mcft (30 000 - 45 000 m3). • This quantity of water, if it is used for irrigation, is sufficient to irrigate 4-6 hectares of irrigated dry crops (maize, cotton, pulse, etc.) and 2-3 hectares of paddy crop.
Factors to be considered: • It should not be located in heavy soils or soils with impervious strata, otherwise the top soil should be porous. • Suitable and adequate soil should be available for forming embankments. • The ideal location of the pond will be on a narrow stream with high ground on either side of the stream. • Simple, economic and efficient surplus arrangement should be possible. • Pond size should be decided on the basis of the catchment area and the number of fillings possible for the pond in the area.
Seepage Losses • The seepage losses from percolation ponds have been assessed by computing the water balance of the ponds. • As far as the percolation ponds are concerned the loss of storage is entirely due to percolation and evaporation.