One may consider nanodams as nothing but a check dam or a micro dam. Unlike check dams or micro dams, Nanodam is a serious effort made in the direction of storing water along the length of riverbed. Check dams are built for water harvesting across canals or swift water flow streams or creeks. However for nanodams, prior emphasis is water storage and than water harvesting. At many nanodams, gravity water harvesting may not be possible (which is true as water is stored below surface land level). However when the need arises, water from multiple adjacent nanodams may be released to fill a major dam downstream, thus enhancing water availability at major dam. Water can also be pumped out of the nanodams for use in smaller quantities.
Microdams are again dams with smaller water encroachment area. On the other hand nanodams will not overflow or flood any area.
Major advantages of Nano dam:
- Additional water body for a given area
- Helps to maintain humidity (advantage of water body)
- Helps to recharge ground water level to certain extent
- Additional water body for bird life
- Enhanced water resource availability
- Nanodams can help to control water velocity due to blockades
- Water evaporation helps in maintaining temperature.
- As continuous flow of water is restricted or controlled, soil removal from major dams at the outer edges is made easier with nano dams constructed upstream.