An MS4 is a system of conveyances that include catch basins, curbs, gutters, ditches, man-made channels, pipes, tunnels, or storm drains that discharges into waters of the United States. An MS4 moves water away from an area into a local water body, such a river, stream, lake, estuary, wetlands, lagoon, or marine waters.

Ventura Coastkeeper’s Watershed Monitoring Program monitors from a multitude of MS4’s throughout Ventura County (click here for VCK monitoring map), and by doing so helps implement the May 2009 Ventura County MS4 Stormwater Permit to improve the water quality of storm water discharged from existing stormwater infrastructure.

Click here to learn how Ventura Coastkeeper’s Watershed Monitoring Program plays a critical role in enabling the enforcement and implementation of the Receiving Water Limitations Provisions of the Ventura MS4 Permit.