While researchers disagree on exactly how climate change will impact future precipitation in California, there is little doubt that it will change and that this will put increased pressure on the state’s water infrastructure. In fact, much of California’s infrastructure is not ready for the impacts of future climate change.

Earlier this year, increased rainfall almost collapsed a wall of Oroville Dam in Northern California. In February, rainfall also caused a landslide along the central California coast, which blocked roads and isolated a Big Sur community for months. In Southern California, the Thomas fire, brought on by especially dry conditions, has destroyed hundreds of homes.

A recent white paper published by the Union of Concerned Scientists (UCS) details the need to develop “climate-resilient infrastructure” in California to prepare for a changing future. In it, Jamesine Rogers Gibson, the author and Western states senior climate analyst for the UCS, notes that when the American Society of Civil Engineers graded the state’s infrastructure in 2012, they gave levee and flood control a D, and urban runoff infrastructure and programs a D+. Gov. Jerry Brown has called for $100 billion to build new infrastructure and repair aging infrastructure. UCS and Gibson say that whatever the state plans to build and repair, they need to do it with climate change in mind.

Water Deeply spoke with Rogers Gibson about the white paper and about building climate-resilient infrastructure.

Water Deeply: When you refer to ‘climate-resilient infrastructure,’ what does that mean?

Jamesine Rogers Gibson: Climate-resilient infrastructure, I would define as infrastructure that is able to withstand extreme events and climate impacts to recover quickly and adapt to them in a way that enables it to function better in a future that is defined by climate extremes.

For instance, from the transportation perspective, if a road is flooded due to extreme precipitation, or a road is closed because it buckles with extreme heat, people are able to get it back up into working order in a relatively quick amount of time with the least amount of negative impacts.

Another aspect of resilience is an idea of recovering in a way that makes [the infrastructure] stronger and more resilient than before. This is an idea that is known as “bouncing forward” rather than bouncing back to the status quo as it was before.

Water Deeply: What made you want to write this paper now?

Rogers Gibson: Here in California and across the country, we’ve recently seen extreme weather events – from the hurricanes earlier this year to the catastrophic floods [resulting] from the 2017 winter storm that led to some pretty significant impacts on our water infrastructure, to the wine country fires – and these extreme events provide us with a preview of what our critical infrastructure will be with climate change. At the same time, California is planning on spending billions of dollars to invest in new infrastructure and to upgrade and retrofit its existing infrastructure. There’s a real opportunity to ensure that we’re doing that right and that we’re doing it in a way that is built to withstand climate extremes.

We view it as an important moment to write this paper to help influence how those funds are spent, but also to raise the urgency of this issue, in that we really need to be better at designing, better at planning, better at building our infrastructure to withstand these climate impacts and keep Californians safe.

Water Deeply: In the paper you note that infrastructure is usually built with the idea that the past is usually a good indicator of what will happen in the future. But due to climate change that is no longer true. How should we be building for a future that is inherently uncertain?

Rogers Gibson: Planning includes considering a variety of conditions for infrastructure in the future, and ensuring that the decisions that we make in terms of how we design infrastructure, what we invest in, where to locate it – that those are all informed by different futures. It’s important to be considering the extreme [predictions] and not just the most likely scenarios.

A helpful analogy is how we build infrastructure for earthquakes, which involves a lot of uncertainty. We don’t know exactly when, where or how the next big earthquake will happen, but that has not stopped us from incorporating seismic risk into infrastructure decisions and creating better building standards to save lives and property.

I think that in addition, it is incredibly important to not view an infrastructure decision in isolation. It’s important – particularly for water – to be thinking about it within the context of the broader infrastructure system. The way you design this piece of infrastructure will influence the entire system’s ability to provide key services that will help communities in California, and elsewhere, continue to provide in the face of a changing climate.

Our infrastructure is becoming increasingly interdependent. We saw this several years ago with Hurricane Sandy, where power outages caused a bunch of cascading failures. As a result of power going out on the water sector, you had sewage spills.

Water Deeply: Since water does impact so much of California, including more conservative agricultural areas, is there sufficient political or social will to revamp water infrastructure in the state?

Rogers Gibson: Attitudes in the agricultural sector are changing, as extreme conditions are forcing farmers and water districts to think about more extreme conditions. There is also an increasing amount of activity to help steward local groundwater resources, especially in low-income communities in the Valley. In addition, every extreme event, including the recent fires in Northern and Southern California, focuses attention on the vulnerabilities that exist in our infrastructure.

Water Deeply: Precipitation in California is expected to change in the future. What will that mean for building climate-resilient infrastructure?

Rogers Gibson: In terms of precipitation, we know that with warming temperatures more precipitation will be falling as rain and increasing the potential for flooding, but also decreasing one of our main sources of water, which is the snowpack. That will affect our water availability.

In addition, we know that this past drought impacted water quality, which meant that wastewater treatment plants had to treat the water and do more than they were designed to do. The increased precipitation will lead to more flooding and will have a host of impacts on our water system, and the increased potential for drought will have a host of impacts on our water system, too. That is why it is so important for us to: 1) when we are designing the infrastructure to consider a range of options, including potential extremes, and 2) to look at the entire system – to look at how different parts of the water system can work together as a whole to ensure that we continue to provide Californians with reliable water.

Correction: This version corrects an earlier version of the story which referred to Jamesine Rogers Gibson as Jamesine Gibson.