Green Infrastructure Can Help California Avoid Another Oroville Dam Crisis
Co-authored by Meg Arnold, Capital Region Climate Readiness Collaborative
As Houston continues recovery, Florida grapples with the aftermath of Irma, and Puerto Rico takes stock of the immense damage from Maria, an unsettling concern grows here in California that widespread flooding, and its threat to the state’s management of water, is a matter of “when” not “if”. Cost-effective, multi-benefit green infrastructure solutions for our state in both the uplands (where the water starts) and the lowlands (where the flood risk is greatest) must become central to the water management dialogue. By prioritizing green infrastructure investments, we can not only bolster flood protection but also improve water supply and quality, reduce carbon emission, support wildfire habitat and promote sustainable economic development.
In California, 20 percent of the more than 39 million residents live within 500-year floodplains. Los Angeles, San Diego, San Jose, and San Francisco are all vulnerable to flooding and Sacramento remains the most at-risk region for a flood event in the nation. This last year we came through a record breaking winter with a near-catastrophe in Oroville – one that resulted in the evacuation of 188,000 people and emergency repairs with a $275+ million price tag. The near-catastrophe at the Oroville Dam highlights the need to diversify the state’s portfolio of flood management safeguards, and to increase the resiliency of its water management. In addition to the maintenance of ‘grey infrastructure’ (e.g. dams, pavement and other impervious drainage systems) to manage water, we must also maximize the substantial benefits of green infrastructure.
Green infrastructure manages water through ecological systems. It can be either natural (e.g. a wetland) or man-made (e.g. a park), and provides ecological, economic, hydrological, and other benefits to society and ecosystems. Much of the Sierra Nevada region—California’s primary watershed—provides natural green infrastructure in the form of meadows and wetlands. Through active restoration these places can increase water storage and prevent downstream flooding by serving as natural pathways and storage systems for water: meadows and wetlands are proven to act as sponges, absorbing precipitation at greater capacity, and releasing it slowly into streams later in the summer for more consistent delivery to the foothills and valley. Natural solutions are also an effective solution in urban environments, slowing down storm water movement and mitigating the urban heat island effect. Green infrastructure can complement and relieve growing pressure on grey infrastructure that lacks the broad co-benefits of green alternatives.
And yet, California’s green infrastructure is in a state of disrepair. The impacts of climate change coupled with other human-induced changes, such as river cutting, unsustainable logging, overgrazing and development of parking lots, roads, buildings and other impervious surfaces, have greatly reduced the Sierra Nevada’s natural capacity for storm-water mitigation. Some 40 to 60 percent (130,000 to 200,000 acres) of Sierra Nevada meadows are already in a degraded state. Droughts alternating, and in some cases, co-existing, with extreme storm events set the stage for dangerous floods, while wildfires in the Sierra Nevada forests and foothills can increase the speed of runoff and erosion.
Developing effective watershed level green infrastructure requires innovative thinking and breakthroughs in institutional barriers that today limit funding and other collaborative opportunities. Grey infrastructure budgets are already stretched thin and funding for maintenance is often deprioritized, as was the case with Oroville. Green infrastructure, with its multiple co-benefits, can be funded from multiple sources, including those that address regional flood control, forest health, wildlife habitat, air and water quality, fire protection, carbon storage and credits, and open space. Funding agencies and local governmental jurisdictions are generally not organized well enough to consider the health and functioning of our watersheds as a whole, which creates significant institutional barriers to cross-sectoral collaboration. Channeling lowland flood protection interests and funding to support upstream protections is not the norm, but can provide significant benefits to all parties involved.
From the averted disaster at Oroville, to the recent disasters from Hurricanes Harvey, Irma, and Maria, climate change is altering the severity of the human impact of water in our lives wherever we live. We would do well to heed these as wake-up calls to California. Developing more effective ways of storing snow and water in the higher elevations could save money and lives. We represent the Capital Region Climate Readiness Collaborative (CRCRC) and the Sierra Climate Adaptation and Mitigation Partnership (Sierra CAMP), respectively. Together we urge state policymakers to prioritize green infrastructure investments that would improve water supply and quality and provide flood protection, as well as generate carbon storage, wildlife habitat and economic development to the upstream communities conducting restoration and the downstream businesses who will avoid disruption.
CRCRC and Sierra CAMP are two of California’s five active regional climate collaboratives (ARCCA), providing forums for the development of climate responsive innovation. Sierra CAMP and the CRCRC are examples of the public-private, cross-sectoral, partnerships that are necessary to find robust solutions to extreme weather events and help prevent future disasters like the Oroville Dam incident.
You can find out more and read the complete report on Green Infrastructure & the Oroville Dam here.
Meg Arnold is Vice Chair of the Capital Region Climate Readiness Collaborative, a project of the Local Government Commission. Diana Madson is the Director of the Sierra Climate Adaptation & Mitigation Partnership, a project of Sierra Business Council.