By Peter Mangarella
Steelhead are a type of rainbow trout with wanderlust. They are anadromous fish, that is, they live most of their life in the ocean, enter freshwater streams only briefly to spawn and then immediately return to the ocean. Of course, streams in California are often dry except during the rainy season, so over the millennia, steelhead have adapted their life cycle to accommodate the California climate. When streams are flowing, steelhead are said to “cue” on the high flows, and enter the streams to spawn. If the climate is such that there are no high flow events, the steelhead just remain in the ocean and await the next rainy season. You could say they are “drought tolerant”.
The female steelhead creates a nest (or “redd”) by turning on her side and flexing her tail to create a depression in the stream bottom. The female lays the eggs and the male then fertilizes the eggs with his sperm or “milt”. The female then covers the eggs again using her tail action. In a couple of weeks, the eggs hatch into small fish called “fry” that live off the attached egg yolk. The fry then must seek shelter and food in cold water streams or pools over the following year until the next wet season, when they begin to move downstream towards the Bay. At this stage, the small fish are referred to as “smolts”.
There is evidence of steelhead in San Francisco Bay. One noteworthy example is Alameda Creek where steelhead have been observed downstream of a large weir beneath the elevated BART line in Fremont. Staff from the East Bay Regional Park District and others would net the fish as they pooled below the weir, implant markers that allowed them to track the fish, and then physically transport them around the weir (and 2 rubber dams operated by the Alameda Water District for water supply) so the fish could access the upper watershed and spawn. Fortunately there are now two state-of-the-art fish passage facilities in Alameda Creek, and this wet season, salmon and steelhead will be able to migrate up Alameda Creek on their own, for the first time in over 50 years. Steelhead have also been observed in other Bay Area streams, including El Cerrito Creek, Marsh Creek, Walnut Creek and Alhambra Creek.
It is in this context, that the Wildcat San Pablo Creeks Watershed Council decided to work on reconnecting the Wildcat Creek watershed so steelhead could more easily move from San Francisco Bay to the upper portion of the watershed in Tilden Park, where there is more suitable spawning and rearing habitat. One of several partial fish barriers in Wildcat Creek is unfortunately a poorly functioning fish passage facility that was constructed in the mid 1990s in North Richmond as part of a flood control project. It is prone to clogging and thus, rather than facilitating migration, it actually inhibits migration (similar efforts at reconnection are being undertaken by the EBRPD in the upper watershed, so this is very much a whole watershed effort).
With support from the California Department of Water Resources (Urban Stream Restoration Program) and the California Fish Passage Forum, the Wildcat Creek fish passage facility is being redesigned to meet current fish passage standards. This Project is referred to as the Wildcat Creek Fish Passage and Community Engagement Project. The project is being managed by the Contra Costa County Flood Control and Water Conservation District, with support from FlowWest Consultants, The Watershed Project, Mithun, and Trout Unlimited.The project includes a redesign (including enlargement) of the facility to provide for improved fish passage and to minimize clogging, while continuing to provide flood protection. Field surveys are also being conducted to ensure that the construction in no way would adversely affect the stability of the structure.
The project also includes obtaining the permits necessary for construction. The permits involve various regulatory agencies including the California Department of Fish and Wildlife, Army Corps of Engineers, and the State Water Resources Control Board. As the project name indicates, community engagement is an important element. We want a project that is people friendly and which will allow for greater enjoyment and connection with Wildcat Creek. As such, staff from The Watershed Project and Mithun are actively soliciting input from the community in terms of potential educational and recreational amenities in the vicinity of Verde Elementary School.
The result of this initial design phase (tentatively through 2023) will be a “shovel ready” project which should qualify for grants that focus on implementation (construction). Efforts are already afoot applying for such funds.