Road vs. Stream in Niles Canyon

State Route 84 twists and turns along Alameda Creek through scenic Niles Canyon between Fremont and Sunol, and it’s sometimes deadly for drivers. An effort by the California Department of Transportation (Caltrans) to make the road safer has hit a roadblock: Environmental groups, local citizens, and the City of Fremont claim that widening and straightening the road will simply encourage drivers to go faster while harming a creek that for years has been the focus of steelhead trout restoration efforts.

The Caltrans draft environmental impact report (EIR) says that although the accident level for the road is below the state average, the number of fatalities is higher than average. The EIR calls for widening a 4.4-mile stretch by 18 feet and straightening the road to provide drivers with longer sight lines. In its comments on the EIR, the San Francisco Bay Regional Water Quality Control Board expressed concern with the project’s impacts on Alameda Creek, and officials warned that they might not issue the permits Caltrans needs to move forward.

Of major concern is the plan to construct 8,700 linear feet of retaining walls. The creekside walls, complete with riprap at their bases, would alter the hydrology of the creek, says Jeff Miller of the nonprofit Alameda Creek Alliance. Caltrans has also proposed to remove hundreds of trees near the creek, many of them natives. Trees provide shade, food, structure, and bank stability important to creek wildlife.

Niles Canyon is a transition zone for Alameda Creek, says Miller. Downstream of the canyon, the creek becomes a flood-control channel that is inhospitable to federally threatened steelhead trout and other cold-water fish. Upstream of the canyon, the bulk of the 700-square-mile Alameda Creek watershed supports a range of riparian creatures. For years, a coalition led by the alliance has been working to restore steelhead in the watershed by removing dams and installing fish ladders and screens. Creek advocates are betting that after a long-anticipated fish ladder is installed at the BART weir in Fremont downstream of the canyon, Alameda Creek in Niles Canyon will serve once again as spawning habitat for steelhead, whose statewide population has seen a 91 percent decline since the 1960s, according to the nonprofit advocacy group California Trout.

Caltrans is reviewing comments on the EIR and, according to Caltrans’ Allyn Amsk, is considering alternatives to address the public’s concerns. Caltrans plans to complete the review process by late spring 2011.