Dear Mr. Gowda Harvested ...
Published by Richard Kuntner, Rural engineer / hydrologist (natural hazard mgt, water resources mgt / water harvesting)
Dear Mr. Gowda
Harvested rainwater (in my understanding: overland flow during storm events collected in reservoirs / ponds or runoff from impervious surfaces like roof tops) can be conserved in terms of quantity and quality.
In order to conserve the quantity of water collected you should minimize the losses due to evaporation and infiltration (mainly in ponds; reduction of evaporation: dimensions of the ponds (higher depth-vs.-surface ratio); reduction of infiltration: impermeabilisation of the pond)
Quality (it is assumed that the overland flow collected does not mobilize any chemical substances on its way towards the collection installation) is mainly an issue if the collected water is used domestically. If irrigation is the main purpose of the water harvesting it is recommended to minimize the amount of sediments / suspended solids mobilized by means of erosion control in the catchment.
Kind regards