Groundwater recharge or deep drainage or deep percolation is a hydrologic process where water moves downward from surface water to groundwater. This process usually occurs in the vadose zone below plant roots and is often expressed as a flux to the water table surface. Recharge occurs both naturally (through the water cycle) and through anthropogenic processes (i.e., "artificial groundwater recharge"), where rainwater and or reclaimed water is routed to the subsurface.

At CMS, we are developing the infrastructure for the storage of non-sewage water and rain water to replenish ground-water aquifers in all campuses. CMS is dedicated to store water to meet demand over time and to Recharge/ reclaim waste water or runoff water and restore/renew natural resources. City Montessori School launched Rainwater Harvesting Project at all its campus on Saturday, 21st July 2012. CMS observed Ground Water Week from 16-22 July in association with Ground Water Department of Uttar Pradesh and the company "Janus", to strengthen their commitment to work for the conservation of water in Lucknow. As a part of this event, CMS launched Rainwater Harvesting Project at most of its campuses, even though the main celebratory event was focused at their new branch in Gomti Nagar II.

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