The Sonoma County Water Agency has released details of the agency’s Green Valley Creek flood control plans to reduce chronic wet weather flooding of Green Valley Road near Graton.
“Last year Green Valley Road was closed for over three weeks due to flooding,” said Lynda Hopkins, who as Fifth District county supervisor also serves as a Water Agency director. “The project would make Green Valley Road safer for the communities who rely on it, as well as the fish and wildlife who rely on the creek.”
When the creek floods, high water on the roadway cuts off access to the Graton community from the west, causing disrupted traffic on Green Valley and Graton roads.
The agency’s Green Valley Creek High Flow Channel Project will remove sediment in the creek west of Graton and restore the creek banks with native vegetation. The Water Agency released a draft initial study and Negative Declaration for the project on June 22. The public is invited to comment on the project before a July 24 deadline.
“Green Valley Creek experiences recurring flooding, leading to extended road closures and hazardous driving conditions on Green Valley Road, stranding fish and wildlife and damaging the roadway and adjacent farmland,” said the Water Agency’s media announcement of the creek plan. “In recent years flooding has become worse, lasted longer, caused more damage, and occurred with greater frequency.”
The proposed project would excavate and maintain channels in the creek and install native plants along the banks to reduce flooding of Green Valley Road and nearby properties and improve aquatic habitat. Construction is expected to start this fall. Annual dry season maintenance would occur as needed for five years.
The project would clear blackberry brush from the creek and an adjacent area in order to establish a temporary access road across a dry channel, excavate creek sediment and install a high flow channel through a gravel bar. Although construction is likely to temporarily disturb fish and wildlife, over the long term the project would improve fish passage, reduce the number of fish stranded by receding floodwaters, improve habitats for other aquatic species and support healthier habitats downstream by decreasing sediment flows from the area, said the Water Agency.
An electronic copy of the draft environmental study is available at www.scwa.ca.gov/environmental-documents. Hard copies are available for purchase by request at 547-1900 or at the Water Agency’s administrative office, 404 Aviation Boulevard, Santa Rosa. Hard copies are also available for public viewing at the Sonoma County Water Agency in Santa Rosa and at the Sebastopol Regional Library.
An initial study is a preliminary analysis of a project’s potential environmental impacts used to determine whether a Negative Declaration or an Environmental Impact Report (EIR) will be prepared. Mandated by the California Environmental Quality Act (CEQA), “the initial study is intended to provide a clear understanding of the environmental impacts associated with the construction and operation of the proposed project for decision-makers, responsible and trustee agencies under CEQA, and the public,” said the Water Agency. If an initial study identifies potentially significant impacts but the project is modified or revised to clearly mitigate the impacts, a Mitigated Negative Declaration may be prepared. If an initial study concludes that a project may have a significant effect on the environment, an EIR would be prepared.