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Blog Post · December 10, 2018

Adapting to an Uncertain Water Future

As the world’s biggest climate meeting continues in Poland this week, the growing threats from climate change―and the lack of large-scale action to match the risks―have been much in the news. Global, national, and statewide assessments all point to severe consequences if greenhouse gas emissions are not greatly reduced. Evidence is growing that climate change is a “threat multiplier,” increasing the frequency and intensity of natural disasters worldwide and here in California. And just this past week, the Global Carbon Project reported that emissions are rising rapidly, making it even more difficult to meet the goals of the Paris Agreement and heightening the possibility of more-frequent and more-damaging climate impacts.

These reports all point to the same policy direction for California. While it is important that the state continue its leadership on reducing greenhouse gas emissions, it is time to greatly increase efforts at adaptation.

Water is where climate change is having its most direct and measurable impact in California. A recent PPIC report found that five climate pressures—warming temperatures, shrinking snowpack, shorter wet seasons, more volatile precipitation, and rising seas—affect all aspects of water. We recommended a suite of integrated reforms to adapt to these changes. These include better planning for water use in cities and farms, and for the environment; upgrading the state’s water management infrastructure; improving the way the state allocates water; and coming up with innovative new funding mechanisms.

Although all of the reforms are important, two—upgrading infrastructure and providing adequate funding—are the most critical. California’s water management infrastructure is vast and complex. Nearly 1,500 dams and reservoirs provide numerous services, some of which are at cross purposes with each other: they store water, reduce flood risk, generate electricity, help maintain downstream ecosystems, and provide recreation. Large volumes of existing and potential storage occur in more than 500 groundwater basins.

The above- and below-ground storage is linked from far-northern California to the suburbs of San Diego by a network of thousands of miles of canals and aqueducts, as well as rivers that function as aqueducts. California could not function without this networked “grid.” This grid is the state’s most valuable asset for adapting to an uncertain climate future.

We recommend that this grid be upgraded. A top priority includes repairing or strengthening dams, canals, and aqueducts—most of which were designed and built more than 50 years ago using outdated hydrology that doesn’t reflect a changing climate. Another upgrade is adding connections to the grid so that water can be conveyed more easily to where it’s needed for replenishing groundwater storage or to support water trading. And integrating operations of the grid, possibly involving a wholesale change in the way it is managed and governed, should also be prioritized.

But talk about upgrading the grid will be insufficient if the state does not find a way to pay for it. The defeat of the statewide water bond, Proposition 3, in November may be an indication of “bond fatigue.” Instead, the burden for paying for this upgrade is likely to fall upon local communities, who already shoulder about 85% of the costs for water management every year. This will be a contentious but necessary public debate. Without new resources, upgrading the grid will be very difficult.

The climate is changing, and the direction of change poses great challenges for California water management. But the state has a very large portfolio of assets to help adapt to this change. If these assets are managed well—and California makes well-funded investments in upgrades and focuses on sustainability—the state can weather these changes with minimal social and economic disruptions.


climate change Drought groundwater Water Supply Water, Land & Air