| California targets polluted stormwater runoff from shopping centers and warehouses |
California regulators have approved landmark rules requiring approximately 600 shopping centers, warehouses, office complexes, and private hospitals in the Los Angeles area to reduce pollution from stormwater runoff, marking the first requirement of its kind in the United States. The regulations apply to properties with at least five acres of impervious surface that drain into the Dominguez and Los Cerritos channel watersheds, where runoff carries contaminants such as heavy metals, oil, grease, and bacteria into creeks, rivers, and beaches. Property owners will be required to obtain stormwater permits and comply by either treating runoff to meet pollution standards, installing infrastructure such as retention ponds or swales to filter contaminants, or contributing to local stormwater improvement projects. State officials estimate contributions to these projects will cost around $4,100 per acre of paved surface, while other compliance options could be more expensive.