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Department of Planning and Development
Department of Planning and Development

Erosion prevention and sediment control

A pathway down a dirt road

Erosion prevention and sediment control are very important for grading operations that are conducted during the rainy season period, usually between October 1st until April 30th each year. Erosion Prevention and Sediment Control measures are an integral part of preliminary grading plans, and by ordinance must be shown on them.

Sediment is a pollutant of concern in local streams, the San Francisco Bay and the Monterey Bay. Stormwater runoff from improperly conducted grading operations contributes to sediment pollution of local waterways. Increased sediment over the natural level is harmful to aquatic organisms and contributes additional mineral loads to streams and bays. It also causes additional expenses for stream maintenance, due to the expense of removal of excess sediment.

Use of Best Management Practices (BMPs) for erosion prevention and sediment control reduces the sediment load in local waterways. Please see sections C12-411, C12-435(d), and C12-517 of the amended Grading Ordinance (attached below) for additional information. For further information, see Storm Water Best Management Practices (BMPs).