The New York City Department of Environmental Protection is working to expand the number of rain gardens throughout the city.

Rain gardens help prevent water from flooding and overwhelming the sewer system — improving the quality of rivers and creeks.

Plants in the gardens were chosen based on the amount of sunlight they need, how much water they can absorb and how well they will work with other plants.

Four thousand rain gardens have already been constructed, and the department plans to install more over the next several years.