County presents drainage study for Sanorita (Little Bear) Creek, directs staff to return with costs in 60 days

Monterey County public works staff on April 1 summarized a new drainage study for the Sanorita Creek watershed, which flows through the unincorporated community of Bulsanol and into the city of Selenus. The consultants modeled channel capacity, historic flooding and a range of project alternatives to reduce flood risk.

The study found the creek’s carrying capacity near Roi Road is about "100 cubic feet per second," a threshold the presenter said the channel reaches before overtopping and flooding nearby properties. Staff said repeated flood events (noted in photos from 2014, 2017, 2020/22 and 2025) have damaged pre‑NFIP homes in the study area; the county’s 2002 floodplain management plan previously identified roughly 60 repetitive‑loss properties in the community.

Consultants evaluated four broad project types: upsizing culverts, routine sediment removal at culvert crossings, selective vegetation management and construction of upstream sediment‑ and stormwater‑retention basins. Staff gave planning‑level cost ranges: culvert upsizing roughly $0.5–$1.0 million; routine sediment cleanouts about $35,000–$40,000 per event; selective vegetation management roughly $50,000–$150,000; and large basin or land‑acquisition projects with greater, as‑yet‑refined costs.

A fifth alternative — clearing the creek to a historical (1970s) condition — was modeled but the consultant concluded it offered no clear advantage in effectiveness or long‑term performance compared with the other alternatives, while permitting and mitigation complications increase cost and difficulty. Staff estimated approximately $2 million would be needed just for environmental review and permits for such large‑scale work, and total permitting plus construction could reach $6 million or more depending on land acquisition and access challenges.

The presentation emphasized permitting risks tied to habitat protections, noting protected species in the area (for example, the California tiger salamander and red‑legged frog) and the potential need for incidental‑take mitigation under state and federal rules. Staff also flagged a major governance challenge: ownership of parcels along the creek is predominantly private, with only limited county‑owned parcels and some parcels owned by local water agencies; that fragmentation increases complexity for construction and long‑term maintenance.

Following the March 24 Board of Supervisors presentation, the Board "directed staff to come back in 60 days" with a more detailed plan that refines project costs (including real‑estate acquisition estimates), sediment removal options, culvert upgrade costs, basin acquisition/construction/maintenance estimates and governance/funding structures. Staff were also asked to consider immediate actions that might be implemented quickly, such as targeted vegetation removal where permits are not required.

Staff said their next steps are site selection, property‑acquisition analysis, environmental review (CEQA and potentially NEPA), and permitting coordination with state and federal resource agencies. The Board did not record a formal roll‑call vote in the briefing transcript; the action was described as a Board direction to staff to return with refined options.