Lessons from Oroville Dam

The evacuation of nearly 200,000 people near Oroville Dam is the kind of event that makes climate change personal. Like many extreme events, the Oroville emergency is a combination of natural weather likely intensified by climate change. 

Dams in the United States were built 50 years ago, on average. Since then, the Earth's surface temperature has warmed about 1.35°F, and there's now more than 5% more water vapor in the atmosphere as a result, which intensifies storms. With hotter temperatures, more precipitation falls as rain and less as snow, and California's Sierra snowpack also melts earlier in the year.

Our infrastructure was designed for yesterday's climate, not today's or tomorrow's. We know the climate is changing and we need to be prepared.

We already see fundamental changes in storm frequency and intensity, increases in the size and duration of droughts and rainfall events, disappearing snow packs, growing agricultural water demands with rising temperatures, and more.

We cannot afford the luxury of pretending climate change isn't real, and we cannot afford to ignore the risks to our water infrastructure posed by these changes. Any investment in infrastructure must take climate change into account through smart flexible design, integration of better weather-forecasting and modeling tools, and adoption of new standards for facility construction and operation.

Environmental groups warned the state about Oroville Dam in 2005, noting that in an intensely wet year like we've seen in 2017, its emergency spillway could erode, and thus should be coated with concrete. State agencies concluded that the cost of this project couldn't be justified given the low probability of such a wet season, but climate change increases the likelihood and intensity of extreme precipitation events.

[Guardian]

Putting Nature Back to Work

On March 19, The American Society of Civil Engineers (ASCE) released its new report card on the condition of America's infrastructure. Overall, our infrastructure in 16 categories ranging from bridges to water systems earned only a D+. ASCE estimates the United States needs to invest $3.6 trillion by 2020 to bring America's infrastructure up to good repair.

Among these systems are several that are critical to reducing the loss of life and property from the growing impacts of global climate change. Dams were graded D; levees earned only a D-; waste water and storm water control systems also were given a D. Drinking water and energy infrastructure — both vulnerable to extreme weather events — received a D and D+ respectively.

The bad news is that the cost of bringing these engineered systems up to par comes at a time when government budgets at all levels are strained, if not in crisis. The good news is that some of the services we receive from engineered systems can be provided instead by natural systems if we restore and protect them.

Ecosystems perform a wide variety of important services for free. Trees provide shade, purify air and water, and store carbon. Wetlands regulate flooding. Coastal marshes buffer communities from storm surges. Forests and soils store carbon as well as water. Many of these ecosystems have been degraded or destroyed by human development. Now, communities need to put nature back to work.

Communities are starting to ask the question -  "Is what you are trying to do, in the way you are trying to do it, going to diminish life or is it going to embrace, protect and restore life?" We call this a living system approach.