How do you assess and mitigate the cumulative environmental impacts of future development? That’s the question that Marin’s environmental planners and contracted scientists have been analyzing in the San Geronimo Valley over the past decade, particularly related to the area’s threatened fish populations.
The effort was the result of a lawsuit brought by the Salmon Protection and Watershed Network in 2012. This week, Marin’s planning commission approved the final version of the document that details the findings—a supplemental environmental impact report to the 2007 countywide plan—and forwarded it to the Board of Supervisors for certification.
While preparing the S.E.I.R., the county’s permitting of development in the valley was stalled on several fronts. Following a court order, the county could not use its 2007 countywide plan—the enormous document that guides policies and programs, including to minimize adverse development impacts on biological resources—for development projects within the valley until it completed the S.E.I.R. In the meantime, the county was forced to use the outdated 1994 countywide plan when reviewing development proposals for the region.
SPAWN’s litigation also stymied a proposed addition to the 2007 countywide plan, a stream conservation ordinance from 2013 that sought to update standards for development near creeks and streams. The county is awaiting the completion of the S.E.I.R. to revamp that countywide ordinance, which it plans to put into effect within five years.
The county released the final S.E.I.R. concerning cumulative impacts last August, with a 21-day public comment period. (The draft circulated a full year earlier.) County staff said they were delayed at every step due to the vast number and complexity of the public comments they received.
On Monday, the planning commission reviewed not only the final document but the county’s responses to those comments—including from all state and federal permitting agencies—in the form of an amendment, a protocol of the California Environmental Quality Act.
The final S.E.I.R. found three potentially significant impacts of cumulative development in the San Geronimo Valley, though none that could not be offset by mitigation measures.
The first potential impact is that urbanization—or increased concrete and other impervious surfaces—will cumulatively increase stormflow magnitude and frequency, compromising the ability of rearing coho salmon to find adequate refuge during high streamflows.
Secondly, the report projected reduced salmonid spawning success due to increased development-related fine sediment in stream channels.
The last potential impact, determined to be minor enough not to require mitigation, was reduced salmonid summer rearing success due to degraded habitat conditions, including reduced habitat complexity, reduced streamflows and increased water temperature.
Although it was not required to do so, the county elected to pursue a number of voluntary mitigation measures to address the latter problem, including a groundwater study to determine how development might adversely impact the summer base flow in San Geronimo Creek as well as stream enhancement projects specific to the summertime.
The primary mitigation measure the county proposed, however, was an update to the stream conservation ordinance that it was blocked from implementing in 2013. The S.E.I.R. lays out the bare bones of what the county hopes the ordinance will accomplish, though the county will not develop the language until the S.E.I.R. is certified.
According to the report approved last week, the stream ordinance would expand the set of development activities that require a discretionary permit and site assessment. Those activities might include vegetation clearing, activities that increase impermeable areas or surface runoff, and alterations to the bed, bank or channel of any stream. There are also several proposed exemptions, including for landowners who agree to partner with the Marin Resource Conservation District to voluntarily restore the creek on their properties.
The S.E.I.R. proposed that the stream ordinance would require site assessments conducted by qualified professionals with at least five years of field experience in assessing potential impacts to stream ecology, riparian ecology and hydrology in coastal California.
In addition, all development would have to abide by a series of standard best management practices, as defined by the future ordinance.
Lastly, discretionary permits for development projects would require a series of building requirements to reduce stormwater runoff, even for small projects that replace or add as little as 500 square feet of impervious surface.
Rachel Reid, the county’s environmental planning manager, emphasized to the Light that the ordinance would refine existing standards and would apply countywide, though it might include specific regulations tailored to individual watersheds.
The planning commission approved the document unanimously. District Four Commissioner Chris Desser was unable to attend, but announced her support for the vote in a letter to the editor.
SPAWN representatives did not attend the hearing, but submitted a letter that stated, “We continue to think the cumulative impacts analysis is not consistent with the appellate court judge’s ruling and is not in the best interest of preserving the native Coho salmon.”
Yet valley residents present at the hearing primarily expressed concerns about the impending ordinance.
“An expanded [stream conservation ordinance] will, number one, discourage voluntary compliance from small homeowners,” said Peggy Sheneman, a Woodacre resident who directs the San Geronimo Valley Stewards. “If anyone thinks that people in the San Geronimo Valley stopped improving their homes in 2009, think again: they just aren’t applying for a permit. Number two, it will increase the cost of public enforcement: the [community development agency] is going to be running all over the county every time someone files a complaint. Three—we have seen already—it reduces affordable housing. You can’t fix up your house as a rental and you can’t add an auxiliary unit.”
Ms. Sheneman, who said her organization represents up to 600 residents, recommended that commissioners include a provision in their resolution that guaranteed consideration of the economic, social and housing implications of a new ordinance—an idea that commissioners rejected.
Other residents took issue with the need for the S.E.I.R. altogether.
Anne Saruman, who owns a creekside home in San Geronimo, expressed frustration with SPAWN. “My feeling at this point, being a homeowner in our area for over 35 years, is that we are being handcuffed by one organization who had over 15 years of projects and litigation, [and] lawsuits against the county. And none of these projects have been successful. Where is the science? Where are we going with all this money? It’s ridiculous.”
Ms. Desser, who said she attempted to get the date of the hearing changed in order to be able to attend, said overall she supported the completion of the S.E.I.R. “We have a pressing need for housing, and based on what we heard at the hearing, there is certainly going to be more development,” she said. “Not only for the people who want to make improvements or maintain their homes, but we also heard from at least two people who want to add rental housing. We have to plan for buildout.”
Ms. Desser acknowledged the financial burden posed by permits and said there needed to be a way for the county to provide financial relief for residents who needed it. She said she continues to discuss avenues for that kind of support with Supervisor Dennis Rodoni.
She also addressed a comment by one valley homeowner who believed fish were taking priority over residents. “The health of the watershed is not just for the benefit of the salmon, but for us all, and we need to look at [cumulative] impacts in that way,” Ms. Desser said. “This is not about caring more about the salmon than the people: we are not disconnected from the ecosystem in which we live. If it’s affecting the salmon now, then we need to take that bigger view.”