Among the many things to see Sunday at the Larchmont Mamaroneck Grow it Green Expo will be rain barrels.

Rain barrels, which attach to downspouts, capture rooftop water that otherwise could  flow into storm drains or over pavement, picking up harmful pollutants from trash and chemicals along the way and carrying them to streams, lakes, and the ocean. In fact, runoff  is the number one source of water pollution in the U.S., according to the federal government.

Residents can use the rooftop water to water plants and lawns and clean cars. Rain gardens are a fun way to use the water too. The rain garden, usually pretty small, can be placed near the downspout where there is a depression in the soil that lets it capture the water for the plants.

Says Mamaroneck Town Supervisor, Nancy Seligson, “The use of rain barrels will help residents conserve water and prevent water pollution in Long Island Sound and we are thrilled that our environmental committee, the Sustainability Collaborative worked with the Administration to get this initiative going.”

Rain barrels will be available for pick up at the ‘Grow It Green” event on Sunday April 10 at the Larchmont Temple from 1-6 PM. To reserve a barrel, call the Town Supervisors Office at 914-381-7805 or visit the program’s website here. A video shows how to use one.

There will also be rain barrels for sale each Saturday from April 16th on (while supplies last) that can be paid for and picked up at the Town’s Recycling Center at 40 Maxwell Avenue during the hours of 8 AM to 11:30 AM.