Rain, Runoff and Revisions: Stormwater Rules Changes for Development Projects

Development projects are now subject to new stormwater runoff rules. Drafted by the Central Coast Regional Water Quality Control Board, the Central Coast Post-Construction Stormwater Management requirements for development projects on the Central Coast are designed to reduce the impact to waterways from urban storm water runoff.

During rain events, urbanized areas with extensive impervious surfaces (roofs, roads, parking lots, sidewalks, etc.) can generate tremendous amounts of runoff. This runoff is concentrated and conveyed (via storm drain systems) to nearby creeks, wetlands and other water bodies in volumes, rates and duration that do not typically occur in natural settings. This can lead to streambed scouring, stream bank collapse and elevated levels of sedimentation that can harm aquatic eco-systems.

The new regulations contain tiered performance measures based upon the square footage of impervious surface area added by a project. These performance measures are cumulative, with projects in higher tiers required to implement the performance measures from lower tiers. The performance measures include site design and runoff reduction, water quality treatment, runoff retention and peak flow management.

In preparing to implement the new regulations, the County of Santa Barbara, in cooperation with the City of Goleta, developed technical guidance materials to assist the development community in designing projects that comply with the new regulations. These materials will also guide municipal planning and engineering staff on how to review project applications to ensure they are in compliance. A series of workshops on implementing the new regulations and use of the guidance materials were held in recent months.

More information on the new regulations may be found at the Central Coast Water Board’s web page and the County’s Project Clean Water web page.