Niles Canyon

Alameda Creek cuts through the coastal hills in Niles
Canyon, winding its way through five miles of steep canyons and sycamore-oak
riparian forest, while dropping nearly 225 feet from Sunol to the bay
plain. The canyon has dense riparian vegetation and the sinuous creek
channel has suitable habitat for trout, but warm water temperatures could
be a limiting factor.
Niles and Sunol Dam Removals
The San Francisco Public Utilities Commission removed two obsolete
dams from the Niles Canyon reach of Alameda Creek in 2006. The removal of
165-year old Niles Dam and 20-foot high Sunol Dam (the largest dam ever
removed in the Bay Area for fish restoration) furthers eventual steelhead
and salmon migration through the canyon.
Gauging Station Barrier
The San Francisco Public Utilities Commission is investigating potential
fish passage improvements at a failing cement structure associated with
a U.S. Geological Survey stream gauge station weir in lower Niles Canyon.
A 2006 report by the Northern California Council Federation of Fly Fishers
and Golden West Fly Fishers concluded the structure may be a migration barrier
to adult steelhead at most flows. Since the gauge has provided over 100
continuous years of stream flow records, there is strong interest in ensuring
any project maintains quality stream flow data. The SFPUC has installed
an alternate gauge above the weir to preserve consistent stream flow records
if the structure should fail or need to be removed or retrofitted.
Abandoned Bridge Footing Removal
As part of a project to replace the 85 year old Alameda Creek Bridge in the middle of Niles Canyon, Caltrans is proposing to remove or modify an adjacent abandoned bridge footing to make it passable for migratory fish. The footing is about 4 high and a barrier for fish migration at low flows. The footing also backs up the creek and creates a warm pool that is habitat for invasive fish and frogs. Removing the footing from the creek channel would improve habitat for native fish and amphibians. The project is scheduled for construction from 2019-2022.