Click here for a new Stormwater Ordinance Manual that guides communities to better safeguard water sources.
Stormwater runoff is water from rain or melting snow that flows across the land instead of sinking into the ground. Stormwater from rain and snow events is a significant source of water pollution in streams and rivers. Large areas of hard, nonporous surfaces commonly built in urban centers can exacerbate the impacts of a rain or snow event. As precipitation runs down rooftops and over dirty streets and sidewalks, it collects pollutants such as oil, fertilizers, litter, and pet waste. All of these pollutants are delivered to streams, rivers, and lakes.