California's Delta, Levees, and Risk

Catastrophic levee failure within the critical delta formed by California's Sacramento and San Joaquin rivers could cause serious harm to people, property, and infrastructure while disrupting the state's water supplies and damaging the delta's ecosystem. As it prioritizes improvements to the aging network of levees that keep floodwaters out of the delta, the Delta Stewardship Council is applying tolerable risk guidelines to better inform decision-making processes and ensure the best use of scarce resources. In addition to applying standard risk analysis methodology to assess flood risks to people and property, the council has developed unique metrics for assessing the risks of disruption to water supplies, harm to the delta's ecosystem, and damage to the unique attributes of communities there, risks that are difficult to quantify and express in dollar terms.