Highlighting Recently Completed Supplemental Environmental Projects

marsh landscape with paved trail stretching off on the left side
The Creekside Marsh Project replaced an undersized culvert to create more tidal exchange in this marsh along a popular trail by Corte Madera Creek.

Supplemental Environmental Projects, or SEPs, allow a discharger to undertake an environmentally beneficial project as restitution for polluting water under the Regional Water Quality Control Board (Regional Water Board)’s enforcement process. For example, an unauthorized sewage or chemical spill into the Bay or a creek could result in a Regional Water Board enforcement action and monetary fines known as Administrative Civil Liabilities (ACLs) levied against the discharger. The discharger may elect to suspend part of the fine by undertaking one or more Supplemental Environmental Projects. SEPs must be related to the location or nature of the violation and should remediate or reduce the probable overall environmental or public health impacts or risks to which the violation contributed, or reduce the likelihood that similar violations will occur in the future.

Since 1999, the Estuary Partnership has managed the SEP Program. Estuary Partnership staff provide independent oversight of select projects, solicit potential projects and maintain an Potential Projects list, and provide administrative support to the Regional Water Board for the program. For more on the SEP Program and the Estuary Partnership’s role, visit https://www.sfestuary.org/supplemental-environmental-projects/

Recently, Estuary Partnership staff successfully closed out four projects: two with East Bay Municipal Utility District (EBMUD), one with San Jose Water Company (SJWC), and one with Ross Valley Sanitary District (RVSD). These projects showcase the breadth of projects in the SEP Program.

One of the two projects led by EBMUD entailed the installation of 1000+ leak detection loggers on water distribution pipes to detect and repair leaks near creeks when they are small, and detect pipe breaks quickly, minimizing the risk of unplanned discharges of potable water to local creeks. For the second SEP project, EBMUD installed fifteen new chlorine analyzers at distribution system reservoirs to remotely monitor chlorine residual levels, allowing for improved public health by ensuring more consistent chlorine residuals in the potable water distribution system. 

For its project, SJWC recently led the update of the Best Management Practices Manual for Drinking Water System Releases for the Cal-Nevada Section of the American Water Works Association. The updated manual for water agencies provides guidance on water main leak detection, unplanned or emergency discharges, mapping sensitive water bodies, and much more.

Site steward Sandra Guldman stands beside an establishing patch of pickleweed and other native marsh plants at Creekside Marsh in April 2021.

RVSD funded a wetland enhancement and revegetation project at Creekside Marsh, a site adjacent to Corte Madera Creek in Kentfield. The project, implemented by Friends of Corte Madera Creek Watershed, upgraded a culvert to increase tidal exchange and replaced some of the existing soil with clean mud from the Bay to make the former dump site more hospitable to subsequent revegetation with mid- and high-marsh plants. The project took over nine years to complete, due in part to unexpected site conditions and evolving approaches to sea level rise adaptation strategies. Site steward Sandra Guldman of Friends of Corte Madera Creek Watershed still rides her bicycle every week to the marsh to manually water the establishing pickleweed and other native marsh plants.