‘Variety of Factors to Blame’ Says Oroville Report

An independent expert from the University of California, Berkeley, this week released a 78-page report outlining what he thinks went wrong with Lake Oroville’s damaged spillway. The news comes during the same week that a Nebraska-based construction company, Kiewit Corp, won a $275 million contract for repairs to the dam’s damaged spillways.

The Sacramento Bee reported that Robert Bea of the Center for Catastrophic Risk Management at UC Berkeley analyzed inspection records and design details about the dam, including a report by consultants released last month. Bea concluded that “the spillway was undermined by a variety of factors, including thin concrete, the presence of ‘soils and incompetent rock’ below the concrete and evidence of water undermining that material,” the Sacramento Bee reported. The design problems were made worse by poor maintenance.

Water Deeply reported earlier this month that highly erodible rock under the spillway likely contributed to its failure. “You go up where that spillway was and the upper 40 to 80 feet of soil is garbage,” J. David Rogers, an expert on dam safety and a professor of geological engineering at Missouri University of Science and Technology, told Water Deeply. “It’s a special kind of metamorphic mess.”

Nevada Braces for Sierra Snowmelt

NASA reported that parts of the Sierra Nevada received more snow this year than in the past four years combined, and the snowpack is up to 80 feet in areas of the Central Sierra. While this is good news for water supply, it may pose flood risks.

Nevada is already preparing for severe flooding that could result from runoff from the Sierra Nevada as temperatures warm in coming months and could create “saturation flooding, much like Katrina,” according to Col. Cory Schulz, the Reno Gazette-Journal reported.

Three Nevada counties have already declared emergencies ahead of potential flooding, and experts have pinpointed areas where dams and other infrastructure could be compromised by high river flows.

Former Lawmakers Join Lobbying Effort for Desalination Plant

Recently retired U.S. senator Barbara Boxer and former state assembly member Fabian Nunez have joined lobbying efforts for a controversial desalination plant in Huntington Beach that has been seeking permits for almost 20 years, according to the Orange County Register.

The plant would produce 50 million gallons of water per day, but environmental groups have fought the project. One of the key issues is whether or not the plant will use subsurface intakes to draw sea water, as Tony Davis reported for Water Deeply in December.

Recommended Reads

• AP: Managers Made Errors in Handling of Dam Crisis
• Orange County Register: Barbara Boxer to Lobby for Desalination Plant in Huntington Beach
• WhoWhatWhy: Deadline Looms for New Water-sharing Deal Between U.S. and Mexico
• Capital Press: Many Areas Struggling to Set up Groundwater Agencies as Deadline Looms