Project aims to develop new tools to allocate limited water supplies
By Janet Byron
Joan Didion wrote in the 1970s that “so much water is moved around California by so many different agencies that maybe only the movers themselves know on any given day whose water is where.” In the half-century since, not much has changed — except for the climate.
“We really struggle as a state to convey basic information about California’s water — where it’s coming from and who is using it, when, and where. This makes it difficult to understand how climate change will affect our access to water and to determine what actions are needed to reduce risks to communities, agriculture, and the environment,” says Ted Grantham, PhD, a UC Berkeley associate professor of cooperative extension.
Grantham leads a two-year, $9.1 million research project called COEQWAL, which stands for “Collaboratory for Equity in Water Allocations.” COEQWAL aims to use sophisticated water and climate modeling — coupled with engagement with dozens of diverse academics, regulators, water suppliers, and water users — to provide California with new state-of-the-art water planning and stewardship tools.
California supplies water to about 40 million people, sustains the most productive agricultural region in the United States, and is a biodiversity hotspot. COEQWAL is the largest of 38 research projects totaling $80 million — funded by the State of California via the University of California — which aim to have a “swift and measurable impact on climate resilience,” according to the University.
“California’s methods for parceling out water were built for a previous era, and not our new climate of worsening droughts and extreme weather,” says Theresa Maldonado, UC vice president for research and innovation. “This project seeks to update those models with the latest climate science, while empowering vulnerable communities to have their say in water policy. These are the first steps toward correcting historical inequities so that people in every corner of the state have access to the water they need for their livelihoods and health.”
Estuary News Group reporter Janet Byron asked Grantham how the COEQWAL project could help California figure out new ways to allocate its limited water supplies as the Earth continues to warm.
JANET BYRON: Why should Californians care about the saying that we have “19th-century institutions and 20th-century infrastructure in a 21st-century climate?”
TED GRANTHAM: That saying recognizes that our legal frameworks, particularly our water rights system, were established in the 19th century. Our oldest riparian and appropriative water rights were established even before California was a state, and they are still active today. Nearly all our major dams, levees, and water conveyance systems were built in the early- to mid-20th century and they were not designed with climate change in mind. Now in the 21st century, we are not only experiencing a novel climate, but also have increasing social demands for environmental sustainability and equity — for making sure that those who are most disadvantaged still have access to water. That just wasn’t part of the plan when our infrastructure and institutions were developed.
BYRON: What’s wrong with California’s existing system for distributing water?
GRANTHAM: California moves water further, through more infrastructure, and with more decision-making authorities than any other place in the world, which makes it difficult to adapt.
We receive most of our water in the north and in the Sierra Nevada mountains, while most demand is in the Central Valley, along the coast, and to the south. To address that mismatch, we’ve built a marvelously complex water management system with hundreds of dams and miles of canals and natural rivers that convey water from its source to end-users. We also have dozens of local, state, and federal agencies that oversee how and where water is allocated as it moves through the system.
This massive infrastructure system has played a central role in building the state’s economy and making California what it is today. But after more than a century, persistent drought, extreme floods, and widespread environmental degradation are exposing significant vulnerabilities in the way we manage water.
BYRON: What is the worst case scenario for the state’s water future?
GRANTHAM: The status quo is not a viable option. We’re facing incredible risks, particularly in the Sacramento–San Joaquin River Delta, which is the hub of the state’s water supply system. The combined effects of a rising sea level and climate change — particularly increasing drought severity coupled with greater flood risks — is making it more difficult to maintain water deliveries to agriculture and cities while also sustaining healthy ecosystems. Extreme floods, for example, are increasingly likely to cause widespread levee failure. This would result in devastating impacts to Delta communities and long-term disruptions to water exports, which will threaten farmers in the San Joaquin Valley and cities in Southern California. Increasing drought also threatens many of our state’s small communities that rely on local water systems.
On the environmental side, we are witnessing troubling signs of salmon population declines and indications that other freshwater species are at the brink of extinction. We’re also seeing emerging problems with water quality, such as harmful algal blooms. Hard decisions need to be made to avoid the worst-case scenarios for people and the environment, and we need to make them with the best information at hand.
BYRON: In your Zoom picture it looks like you’re wearing waders. Have you always been interested in water?
GRANTHAM: I love being on rivers. I grew up in Humboldt County on the North Coast, where I experienced the beauty of rivers but also witnessed their sensitivity to watershed mismanagement, especially poor logging practices.
While my education focused on freshwater ecology and hydrology, I’ve always been fascinated by the interface of science, policy, and management, especially in thinking about how we integrate environmental needs in the way that we manage water. To address that question, we need to understand how ecosystems respond to changes in water availability, and how we might modify water allocation policies to better balance human and ecosystem needs.
Research in my lab involves sampling fish in the environment, measuring stream flow and water quality parameters, and trying to make sense of the way that our freshwater ecosystems are responding to environmental change.
BYRON: Does the COEQWAL project have a specific goal?
GRANTHAM: We are not advocating for a particular strategy or solution. Rather, our goal is to provide all Californians the information needed to make sensible decisions about how to adapt our water management system in ways that are resilient, sustainable, and equitable. It’s remarkably difficult to access information about how water is being moved around the state, to simply track water from a source to its ultimate end-use. Without this information, it’s hard to have nuanced conversations around our water future and how we might do things differently to better position ourselves for the future.
BYRON: What is a collaboratory?
GRANTHAM: It’s a combination of collaboration and laboratory. It conveys the idea of a collaborative space for participatory modeling, knowledge integration, and scenario exploration. It’s an approach to addressing big issues like climate change that require collective action. Our collaboratory team includes researchers from six UC campuses and California State University, Sacramento, and includes social scientists, climate scientists, engineers, economists, ecologists, and data scientists. We have also established partnerships with many organizations and agencies engaged with California water issues.
BYRON: What’s special about this particular collaboratory?
GRANTHAM: One novel aspect is that we are orienting this project around the perspectives of diverse stakeholders. These include government agencies and water users, but also those who have not traditionally had a seat at the decision-making table, such as Native American Tribes, environmental organizations, and community organizations. Through our engagement with these groups, we aim to explore a much broader universe of possible water futures for the state. This means that we will be considering alternative water management scenarios that substantially deviate from the status quo.
In addition, we are committed to making all of the data we generate for this project accessible to the public. Currently, it is very difficult to access data used in water planning and to the extent that information is available, only a small number of people with specialized expertise can make use of it. We want to change that. Our vision is for any individual to be able to pull up a website, identify their location on the map, and explore how alternative water management scenarios will affect their water security and priorities. We are basically trying to create a digital sandbox of the state’s water system to explore how allocation patterns might change under distinct climate and operational alternatives.
BYRON: What can your new models — your “digital sandbox” — do that couldn’t be done before?
GRANTHAM: We’re deploying a model called CalSim3, which is used by state and federal agencies responsible for long-term water planning, to simulate how California’s water management system is operated. The model includes a representation of every reservoir, every piece of infrastructure, and nearly every end-user that receives water from the Sacramento–San Joaquin River watersheds. We first specify the climate inputs that determine inflows into reservoirs and flows into the Delta; these are specific precipitation and temperature regimes and degrees of sea-level rise that represent both historical and future climates drawing from the latest projections for California. Next, we specify objectives for how available supplies are allocated in the system. This will include changes in reservoir operation rules, environmental regulations, and the relative priorities of water users based on their water rights or contracts. With the model, we can then explore how different combinations of rules and climates affect water deliveries to people and the environment.
In addition, we are doing a deeper dive into three particular topics, which we call “use cases,” to understand what alternative water scenarios may mean for drinking water access for disadvantaged communities, salinity management in the Delta, and Chinook salmon populations.
BYRON: How will your project shift the perspective of entrenched water warriors?
GRANTHAM: One of the most important contributions of our project is to better understand the nature of trade-offs under alternative scenarios. The fact is, there will never be enough water to satisfy everyone’s demands, and trade-offs are inevitable. But most debates around California water tend to portray the trade-offs as a zero-sum game. Take the “fish versus farms” dialogue that has dominated California water for 50 years — the idea that any drop of water that goes to the environment is being taken from farmers, and vice versa. That has always struck me as a false dichotomy. With this project, I hope we can bring much more nuance to our understanding of the trade-offs. I suspect there are some scenarios that are good for fish and farmers in some places, but perhaps more significant trade-offs in others. With COEQWAL, I hope that by illuminating these dynamics through compelling visualizations, we can have more productive conversations around how to balance diverse objectives for California’s water.
BYRON: What steps is the COEQWAL project taking to draw more hard-to-reach communities into the conversation?
GRANTHAM: The success of this project will depend on our ability to effectively engage communities and uplift voices of groups that have largely been excluded from decision-making around water. We have reached out to Native American Tribes in particular, but also other water-insecure communities, such as Kettleman City. Through surveys, interviews, and workshops, we want to directly ask communities about their vision of how we might manage water differently. We will translate that vision into specific scenarios that we can run in the CalSim3 model, and then share the outcomes back out to the public.
In terms of Indigenous community concerns, we’re working with several tribes in the Central Valley, including the Shingle Springs Band of Miwok Indians and the Buena Vista Rancheria of Me-Wuk Indians, to understand their unique perspectives on California water. We are also partnering with the Yurok and Karuk tribes, whose ancestral territories include the Trinity and Klamath rivers. A large water diversion in the headwaters of the Trinity River transports water out of the basin to the Sacramento River. As a result, a significant proportion of the natural flow of the Trinity has been lost, which has contributed to declines in the salmon populations that are so critical to the culture, health, and vitality of those tribes. We will be working with the tribes to think about what it would mean to operate the Shasta/Trinity River Division Project, the reservoirs and canals that export water from the system, in a way that could be more protective of salmon and important cultural resources.
BYRON: How do your own views on climate change square with this work?
GRANTHAM: Being at the University of California, I see amazing work happening around climate science and technological approaches for tackling the climate crisis. But I still perceive a major disconnect between the science — the information that’s coming out about the risks of climate change and new mitigation strategies — and the extent to which the public and policymakers are responding. There’s a critical but overlooked role for the type of collaborative, community-engaged work represented by this project. I hope that if we are successful, we’ll not only get closer to the solutions we need in California water, but also inspire those working on other natural resource, energy, and public health challenges to take a similar approach.
BYRON: Isn’t the 2-year timeline for COEQWAL a bit optimistic?
GRANTHAM: (Laughs) It’s very, very ambitious.
We’re trying to bring in a broad diversity of participants who are generally not engaged in water decision-making, which is going to take some time and trust-building. Honestly, it’s going to be challenging to pull off in this timeframe. But we have to get started.
Even if we get halfway to where we want to go in the next two years, it will represent tremendous progress in making water information more accessible and empowering the public. Enhancing community participation in water decision-making for California is essential for collectively making hard choices as we look to the future.
Estuary News Group produces articles for Maven’s Notebook with funding from the Delta Stewardship Council.
