Catch basins - variously known as "storm sewer grates", "drains", or "storm drains" - are scattered throughout the area. They drain stormwater to area streams and to the Huron River, without any further water treatment except for the settling of sediment in the basin.

A map of Ann Arbor storm drains is also available in KML and shape file formats.

Cleared storm drains are important to prevent flooding of roads and streets.