Ubiquitous in the urban landscape, concrete channels embody a mid-20th-century attitude of subduing nature and maximizing developable land. Yet these optimistically-engineering structures have proven hard to maintain, and society increasingly regrets the loss of riparian ecosystems and the opportunity for human recreation and renewal once offered by the natural streams. As concrete channels inevitably age and reach the end of their design lives, river managers confront the question of what to do with this deteriorating infrastructure. Can the channels be rebuilt or modified to pass floods increasing due to urbanization and climate change? Or is this an opportunity to implement alternative approaches that restore valuable functions of natural rivers?
These issues are highlighted in the San Francisco Bay Region, where multiple concrete channels suffer from sedimentation problems and one county has adopted a policy to replace them with natural channels where possible, and on the Los Angeles River, where the US Army Corps of Engineers has just released a draft Integrated Feasibility Study for ecosystem restoration of an 11-mile reach. Scholars, practitioners, and managers will share ideas and experiences from California and elsewhere in the US, and look forward to the challenges and opportunities of rethinking the concrete channel. The conference will wrap up with an exhibition of Concrete Channel Art.
Speakers include Carol Armstrong (City of Los Angeles), Mitch Avalon (Contra Costa County Public Works), Josephine Axt (US Army Corps of Engineers – shutdown permitting), Jack Curley (Marin County Public Works), David Fowler (Milwaukee Metro Sewerage District), Jeff Haltiner (ESA-PWA), Ralph Johnson (Alameda County Public Works), Jim Fiedler (Santa Clara Valley Water District), Lewis MacAdams (Friends of Los Angeles River), Scott Nicholson (US Army Corps), Chip Sullivan (UC Berkeley), Phil Williams (ESA-PWA).