Functional Flows for Developing Ecological Flow Recommendations

by Sarah Yarnell, Alyssa Obester, Ted Grantham, Eric Stein, Belize Lane, Rob Lusardi, Julie Zimmerman, Jeanette Howard, Sam Sandoval-Solis, Rene Henery, and Erin Bray

To protect California’s native aquatic species, stream flows need to be managed to support important ecological processes and habitat needs.

In practice, such flows are difficult and controversial to define and implement. Water diversions, dams and other water infrastructure, land drainage, and changing climate conditions have altered the timing and availability of water, creating demands that impair restoration of the full natural flow regime. While restoring full natural flow regimes in California rivers may not be possible, preserving key aspects of the flow regime, or functional flow components, may provide a means to conserve the state’s freshwater ecosystems.

What are functional flows?

The functional flows approach provides a basis for estimating how much water is needed for the environment, where key components of the natural flow regime are targeted rather than the full natural flow regime. Desirable functional flow components have a disproportionately important role in supporting the physical and ecological processes that create and maintain habitat and trigger native species to reproduce, thrive, and migrate.

A natural versus functional flow regime. The functional flow regime preserves key aspects of the natural hydrograph. From Yarnell et al. 2015.

This process-based approach preserves the most important aspects of the variability of a natural flow regime to which native species have adapted.  It differs from environmental flow methods that focus on single species and their habitat requirements by instead capturing the needs of biological communities.

Most rivers in California have four functional flow components of the natural flow regime represent significant drivers of geomorphic and ecological processes:

  1. Wet-season initiation flows, or the first major storm event following the dry season. These flows represent the transition from dry to wet season, and serve important functions such as moving nutrients downstream and signaling species to migrate or spawn.
  2. Peak magnitude flows, which transport a significant portion of sediment load and maintain and restructure river corridors.
  3. Spring recession flows, which signify the transition from high to low flows and provide reproductive and migratory cues and redistribute sediment.
  4. Dry-season low flows, which favor native species adapted to withstand stressful periods.

Each of these four components are quantified by flow characteristics, including magnitude, timing, duration, frequency, and rate of change. Together, these aspects of flow comprise a functional flow regime; no single component or characteristic alone constitutes a functional flow regime. The relative importance of functional flow components may vary locally, while flow characteristics will likely vary based on water year type (dry, moderate, wet conditions). Year-to-year hydrologic variability provides periodic disturbances needed to support diverse aquatic and riparian communities. Additionally, characteristics should remain similar to natural values observed historically in order to protect native species and ecological processes.

Functional flow components are quantified using relevant flow characteristics linked to geomorphic and ecological processes.

While the functional flows approach can help estimate environmental water needs, it may not by itself provide a solution to ecosystem recovery. Additional physical habitat restoration may be required to realize the full benefits of a functional flow regime. For example, channel floodplain connections may be needed to support benefits of high flows that provide habitat diversity. Additional management measures may be needed to address a spectrum of water quality concerns in a watershed, including stream temperature, nutrients, sediment, and dissolved oxygen. These factors should be considered and explored further when utilizing a functional flows approach. Chapman et al. (2018) illustrate the success of this type of approach for Putah Creek, California.

How could this approach be applied in a management context?

A recent PPIC report recommended establishing an ecosystem water budget, which would allocate a block of water to the environment. Such budgets would bring the environment to the table as a partner in water management and allow for the trustee responsible for managing that water budget to participate in buying and selling water.

The functional flows approach provides a strategy for defining and allocating ecosystem water budgets. For example, by quantifying the functional flow components for a particular system, they can be aggregated to estimate an annual ecosystem water budget. Once budgets are established, they can also be used to guide when environmental water allocations are necessary to achieve targeted flow functions, for example by releasing water from dams at critical times to increase peak winter flows, or by curtailing water diversions to ensure that summer baseflows remain within the targeted range required for ecosystem health. An ecosystem water budget informed by a functional flows approach also offers flexibility during changing conditions (wet and dry years) by providing context to consider seasonal or interannual differences in allocations that can balance ecological and human use.

Hypothetical functional flow regimes in a California river in wet and dry years. Initial environmental water budgets for different water year types are computed as the annual volume of water required to meet functional flow requirements.

The functional flows approach offers a flexible means of informing flow recommendations that capture significant processes upon which native species are hypothesized to depend. This approach could be an effective way to manage an ecosystem water budget for California that preserves important components of the natural flow regime.

Sarah Yarnell and Alyssa Obester are affiliates of the UC Davis Center for Watershed Sciences. Ted Grantham is faculty at the University of California, Berkeley, and an affiliate of the Center for Watershed Sciences. Eric Stein is a Principal Scientist at Southern California Coastal Water Research Project. Belize Lane is faculty at Utah State University. Rob Lusardi is also a researcher at the Center for Watershed Sciences and is the UC Davis-California Trout Coldwater Fish Scientist. Julie Zimmerman and Jeanette Howard are affiliated with the Nature Conservancy. Samuel Sandoval is an Associate Professor in the Dept. of Land, Air and Water Resources at UC Davis and an UC Agricultural and Natural Resources Cooperative Extension Specialist. Rene Henery is with Trout Unlimited. Erin Bray is faculty at California State University, Northridge. These individuals are continuing to work on implementing a functional flows approach across California via the Environmental Flows Workgroup, a sub-group of the California Water Quality Monitoring Council. Stay tuned for upcoming related blogs.

Further Reading

Chapman, E., E. Jacinto, and P. Moyle (2018). Habitat Restoration for Chinook Salmon in Putah Creek: A Success Story. California Water Blog.

Jeffres, C. (2011). Frolicking fat floodplain fish feeding furiously. California Water Blog.

Mount, J., Gray, B., Chappelle, C., Gartrell, G., Grantham, T., Moyle, P., Seavy, N., Szeptycki, L., and Thompson, B. (2017). Managing California’s Freshwater Ecosystems: Lessons from the 2012–16 Drought. Public Policy Institute of California.

Poff N.L., Allan J.D., Bain M.B., Karr J.R., Prestegaard K.L., Richter B.D., Sparks R.E., Stromberg J.C. (1997). The natural flow regime. BioScience 47: 769–784.

Yarnell, S.M., Stein, E.D., Lusardi, R.A., Zimmerman, J., Peek, R.A., Grantham, T., Lane, B.A., Howard, J., and Sandoval-Solis, S. (2018). An ecologically based approach for selecting flow metrics for environmental flow applications. In Review. Journal of Ecohydraulics.

Yarnell, S. M., Petts, G. E., Schmidt, J. C., Whipple, A. A., Beller, E. E., Dahm, C. N., … Viers, J. H. (2015). Functional Flows in Modified Riverscapes: Hydrographs, Habitats and Opportunities. BioScience, biv102.

Willis, A. (2018). The folly of unimpaired flows for water quality management. California Water Blog.

Posted in Conservation, Planning and Management, Water Markets | Tagged , , | 4 Comments

The folly of unimpaired flows for water quality management

Canyon section of the Shasta River in the late fall when spawning Chinook return and the focus of a water transfer program to address water quality conditions. Photo: Carson Jeffres

by Ann Willis

Unimpaired streamflow has long been the benchmark against which current stream flows are evaluated for environmental purposes. The underlying assumption is that if there is water in a stream, the stream must be healthy.

A closer look shows why unimpaired flows is often a flawed basis for environmental management, particularly when water quality is the primary problem.

Environmental flow studies seem ubiquitous. In California’s Shasta River watershed, a tributary to the Klamath River, unimpaired flows have been the basis of recent Instream Flow Needs studies. Recently, another study uses unimpaired flows for a larger regulatory effort to address California’s Water Action Plan.

The approach in the draft Shasta River study plan follows a familiar pattern: first, develop a flow model to better understand current water supply, water demand, and instream flow patterns. Then, remove all human activity (e.g., diversions, pumping, storage) to estimate unimpaired flows. Ultimately, use the model to evaluate water management scenarios that address ecosystem objectives – in California, these ecosystem objectives frequently focus on anadromous fish such as salmon.

At first, such an approach seems reasonable and systematic. However, a regulatory strategy built on unimpaired flows makes critical assumptions on how streams work; assumptions that seem increasingly invalid.

Four questionable assumptions form the basis of many unimpaired flow strategies:

  1. Today’s unimpaired flows would support anadromy and native fish.

Because salmon thrived in rivers before European settlers diverted flows for mining/agriculture/etc, many assume that they would thrive again if diversions stopped today. Many streams have had too much water diverted for too long, resulting in a persistent environmental drought. But unimpaired flows do not guarantee that other vital conditions exist for fish to thrive (like desirable stream temperature, dissolved oxygen, or nutrient levels). Further, climate change has already influenced a variety of physical and ecological conditions, including the timing of flows as snowmelt shifts earlier to rainfall runoff.  Thus, even if we could restore unimpaired flow patterns to our streams, historical conditions may no longer be a realistic benchmark for current or long-term management.

  1. Water temperature and water quality problems are changed by instream flow management.

Stream temperature is a major characteristic of aquatic habitat. It drives water quality processes, food webs, animal health, reproductive success, and much more. Stream temperature is naturally influenced in many ways.  Developing a management strategy for stream temperatures requires understanding the processes that drive those temperatures.

Aquatic plants form a natural canopy in Big Springs Creek, and control water temperatures during mid- to late-summer.

In the Shasta River, the things that drive temperature change as the river flows downstream. In some areas, aquatic plants control water temperature. In other places, stream temperatures are controlled by large groundwater springs far upstream that overwhelm other local influences, including diversions (similar phenomenon have been observed downstream of large dams, too). Eventually, water flowing on the surface reaches a balance with surrounding air temperature. In these situations, more water does little to influence temperature (or other water qualities), so unimpaired flows often fail to address undesirable temperature.

Generally, stream flow and water temperature are inextricably linked. But for stream temperature problems, flow-based management strategies is not always the right approach.

  1. Watershed-scale models provide detailed insights for managing localized water temperature and water quality.

Fish management is as much a question of water quality as it is water quantity. Often, the data needed to understand and model these processes is highly detailed and covers many features.

Watershed models look at large areas, when the true areas of interest may only be a few key places. The Shasta Basin (outlined) is part of the much larger Klamath Basin (inset). Source: UC Davis Center for Watershed Sciences

Watershed models are the 30,000-ft view of these processes. Modelling an entire watershed to develop a management strategy specific to anadromous fish and water quality issues is like using a wide-angle lens when you really need a magnifying glass.

Local actions have local results that are often lost in a watershed-scale model. Cumulatively, many local actions may be needed to mitigate basin-scale problems. But the right combination of specific, effective local actions can only be identified on a more detailed scale than can be shown by a watershed-scale model. Figuring out where the priority areas are depends on a dedicated investigation to understand the underlying processes, which leads to myth #4:

  1. “Best available data” will be enough to develop effective, watershed-wide regulatory management.

Regulators are in the unfortunate position where they must implement regulatory policies, but can only implement effective strategies on the “best available data.” The “best available data” may be insufficient to define the underlying stream processes that prompt regulatory actions. Nevertheless, agencies are mandated to regulate, whether or not data is available to develop effective strategies.

Generally, no one benefits from a poor understanding of stream processes. Science brings vital insights that are necessary to manage our resources, including what data we can afford to forgo and what data we cannot. The scientific studies funded as part of Proposition 1 are good examples of how public investment can realize public benefit through well-informed scientific findings. But Prop 1 science funding is limited to the Delta.  Proposition 68 focuses on projects in California’s rivers and streams, including the Klamath, but has no comparable funding category for scientific studies of those areas.

The Klamath watershed, though geographically remote, has already seen regulatory and litigation decisions that have profound implications for the rest of California, including the Delta. Though the short-term result of robust public funding for watersheds like the Shasta and Klamath may be an uncomfortable admission of how poorly we have understood our rivers and streams, in the long-term we provide more stability to all water users and more effective guidance to regulatory policies. A step away from unimpaired flows as a default framework for managing our streams would be a step in the right direction.

Ann Willis is an engineer at the Center for Watershed Sciences and PhD student in Civil and Environmental Engineering at U.C. Davis. Her work is currently supported by fellowships with the National Science Foundation (Graduate Research Fellowship Program) and the John Muir Institute for the Environment.

Further readings

Paradigm Environmental. 2018. Draft Shasta River Watershed Characterization and Model Study Plan.

Willis et al. 2017. Seasonal aquatic macrophytes reduce water temperatures via a riverine canopy in a spring-fed stream.

Nichols et al. 2014. Water temperature patterns below large groundwater springs: management implications for coho salmon in the Shasta River, California.

Willis et al. 2015. Instream flows: new tools to quantify water quality conditions for returning adult Chinook salmon.

Posted in California Water | Tagged , , , , , | 3 Comments

Striped Bass in the San Francisco Estuary: Insight Into a Forgotten Past

A typical commercial fishing boat of the 1920s, drifting gill nets upstream of Carquinez Strait. Fisherman would often spend multiple days on the water, unloading their daily catch on “pick up” boats operated by SF fish dealers. Photo: W.L. Scofield, 1926.

by Dylan Stompe and Peter Moyle

Striped bass are well known throughout California as a hard-fighting game fish, excellent table fare, and a voracious predator on other fish. Striped bass were introduced into the San Francisco Estuary in 1879 and are often cited as a major cause of native species decline. Historically they were valued as a strong indicator of estuary health, as well as a very important game fish. In fact, key ecological monitoring programs in the estuary were established in the 1950s and 60s to keep track of striped bass populations.

Because striped bass are one of California’s best-studied fish species, there is an abundance of historical data regarding their abundance, distribution and diet. By tapping into this information we can build a better understanding of California striped bass life history and historical trends, and better understand their role in the San Francisco Estuary ecosystem.

We have recently embarked on a project reviewing the life history, biology, and status of striped bass within California waters, as compared to their native waters of the East Coast. Through our plunge into the historical literature, we have uncovered a series of largely forgotten facts about striped bass which we present here as a brief quiz. Answer the questions below to test your knowledge of California striped bass. Consider yourself an expert if you get 7 of the 10 answers right. Answers are at the end of the blog.

  1. From which state did California’s striped bass originate?

a. North Carolina

b. New York

c. New Jersey

d. Connecticut

2. Approximately how many striped bass were introduced to the San Francisco Estuary?

a. 15

b. 145

c. 435

d. 1505

3. When was the first striped bass caught on the West Coast outside San Francisco Bay reported?

a. 1880

b. 1882

c. 1887

d. 1892

4. In what year did the commercial fishery begin in earnest for striped bass in California?

a. 1880

b. 1889

c. 1893

d. 1900

5. In 1893-1894 what was the average weight, in pounds, of striped bass sold in the San Francisco fish markets? (N = 1,461)

a. 1

b. 3

c. 7

d. 11

e. 15

6. What were the main fish consumed by adult striped bass in the San Francisco estuary in the 19th century?

a. Delta Smelt

b. Chinook Salmon

c. Juvenile Striped Bass

d. Native Minnows

e. Common Carp

7. In which river were striped bass most common in the 19th century?

a. Mokelumne

b. San Joaquin

c. Sacramento

d. American

e. Feather

8. What’s the unofficial largest striped bass to have been caught by hook and line in California (to the nearest pound)?

a. 45

b. 68

c. 74

d. 88

e. 95

9. In what year were statewide regulations first adopted for the protection of the striped bass fishery in California?

a. 1905

b. 1909

c. 1916

d. 1920

e. 1922

10. What was cited as the initial cause of striped bass population decline in California waters?

a. Altered Flow Regimes

b. Entrainment in Pumps

c. Pollution

d. Prey Decline/Change in Prey

e. Commercial Fishing

Observations on the historical diet, abundance and distribution of striped bass give us a better understanding of estuary conditions in the past. For example, their apparent preference for carp as prey in the late 1800s indicates that other non-native species were already abundant in the system. It also suggests that the bass were feeding on the bottom, in shallow, turbid water. Likewise, the apparent change of preference in rivers for spawning from the San Joaquin to the Sacramento in the 20th century is another indicator of changing river conditions from a time when flow and water quality data is sparse.

An 87.5lb striped bass, caught in San Antonio Creek by Charles R. Bond in 1912. San Antonio Creek is a small tributary to the Petaluma River in Petaluma, California. Photo courtesy of the Marin Rod and Gun Club.

The changes in attitude of people towards this fish are also instructive. Striped bass started as a much-heralded introduction to provide a familiar and prized fish for the tables of residents of the SF Bay region. Its population explosion resulted in a huge commercial fishery, which was eventually abandoned in favor of the sport fishery.

By the 1930s, it was revered by all as one of the best game fishes in California, for both sport and table. By the 1960s, it was recognized as an abundant, but probably declining, species, in part because of changing conditions in the estuary. This resulted in flow regulations to protect the bass and monitoring programs to track their abundance.

In the last 10-15 years, the management paradigm has shifted again: striped bass are now regarded as an alien invader that suppresses populations of declining salmon and smelt, despite its concurrent population decline and value as a game fish. Perhaps this paradigm should be reconsidered: should we instead treat striped bass as a sentinel species to provide insights into the condition of the SF Estuary?

Regardless of your own opinion of California striped bass, it is clear that there is value in understanding its history and gaining insights into the SF Estuary’s ecosystem that this much-studied species affords.

Dylan Stompe is researcher at the Center for Watershed Sciences, studying the abundance, distribution and life history of striped bass in the San Francisco Estuary. Peter Moyle is Distinguished Professor Emeritus at the University of California, Davis and Associate Director of the Center for Watershed Sciences.

Further reading

Scofield, Eugene. 1931. The Striped Bass of California (Roccus lineatus)California Division of Fish and Game Fish Bulletin 29:  84 pp.

Scofield, N. and H. Bryant. 1926. The Striped Bass in California. California Fish and Game 12 (2) :55-74

Smith, Hugh. 1895. The Striped Bass History and Results of Introduction. U.S. Fish Commission Bulletin. Vol 15.

Quiz Answers:

  1. C; The first introduction was sourced from the Navesink River and the second from the Shrewsbury River. Although separate rivers, they both drain into the same estuary and may have been effectively the same population.
  2. C; 435: 135 in the first introduction, 300 in the second.
  3. A; An eight inch bass was reported to have been caught in Monterey Bay, just 6 or 7 months after the first introduction. The first confirmed report in SF Bay occurred several months after that.
  4. B; The commercial fishery quickly ramped up to a maximum harvest of 1.8 million pounds in 1915. The commercial fishery was then banned in 1935 in favor of the growing recreational fishery.
  5. D; Average sizes were dependent on month of capture, with a range of 7 to 14 pounds during this time period.
  6. E; Anecdotal accounts from bass examined both in the fishery and in the fish market indicated that carp were a major prey of bass of all sizes. Carp were introduced to California seven years prior to striped bass, in 1872, and presumably were experiencing their own population explosion.
  7. B; There are many observations of aggregations of striped bass in the San Joaquin River, apparently for spawning, in the 19th and early 20th centuries. In contrast, commercial salmon fishermen in the Sacramento River rarely reported catching striped bass during the same time period.
  8. D; On the wall of the Marin Rod and Gun Club is a picture of an 87.5 lb striped bass caught in a tributary to the Petaluma River in 1912.  The current IGFA world record of for striped bass of 81.88lbs was caught in 2011 in Connecticut
  9. B; A ban on export of striped bass from California, as well as a ban on commercial fishing for striped bass during spawning season, was adopted in 1909. Regulations became stricter after a record harvest in 1915, in part due to pressure from recreational anglers.
  10. E; While the fishery was blamed for the decline from the days of super-abundance, even early observers thought multiple factors were involved, including dams, water diversions and pollution.
Posted in Delta, Fish, Sacramento-San Joaquin Delta | Tagged , | Leave a comment

Eastern San Joaquin Valley and other CA drinking water supplies at risk in the next drought

Donna Johnson, 70, (L) lifts pallets of donated bottled water from the back of her truck during her daily delivery run to residents whose wells have run dry, with resident Gabriel Tapia, 31, in Porterville, California October 14, 2014. Picture taken October 14, 2014. REUTERS/Lucy Nicholson

by Amanda Fencl, Rich Pauloo, Alvar Escriva-Bou, Hervé Guillon

During the 2012-2016 drought, the state received more than 2,500 domestic well failure reports, the majority of which were in the Central Valley (DWR 2018). This left thousands of people without a reliable source of drinking water for months and, in some cases, years. The crisis drew national attention as well as local and state investment and intervention in many communities.

The next drought might be just around the corner, pushing farmers and cities to pump more water from the ground again, and risking the primary water source for the estimated 1.44 million Californians that rely on domestic wells for drinking water and household use (Dieter et al. 2018). These people are responsible for maintaining their own water supply; during droughts, they are “first to suffer […] in cabins in Modoc County, among  … the hills of Paso Robles, in the farmworker towns of the San Joaquin Valley” (Santa Cruz Sentinel 2014). Would we be ready to deal with the next crisis? Can we plan in advance to avoid such problems?

One of the ways to be better prepared is by strengthening rural drought resilience and identifying who is at risk and vulnerable to experiencing domestic well failure. As part of the 2018 #CAWaterDataChallenge, our team created a  tool-oriented research product that addresses three specific questions:

  •       Which domestic wells will be vulnerable in the next drought?
  •       Are disadvantaged households disproportionately affected by drought-vulnerable       wells?
  •       Can we identify characteristics of the vulnerable wells that will worsen with climate change?

Our submission was driven by open data from public agencies and assessed the vulnerability of domestic wells to failure in the Central Valley.  Using the Department of Water Resources’ (DWR) seasonal groundwater level measurements, we interpolated groundwater levels in the shallow to semi-confined Central Valley aquifer system. Then, a spatial model of well failure was built and calibrated to actual, reported well failures collected by the state during the 2012-2016 drought (DWR 2018).  The spatial point pattern of our model’s predicted well failure during the 2012-2016 drought matched observed well failure point patterns reported to the state as dry or failing wells.

Which domestic wells will be vulnerable in the next drought?

Assuming no interim intervention to resolve existing or prevent new well failures, our project shows where domestic wells are vulnerable in future droughts.   A well fails when the groundwater level in a drought scenario falls below the level of the pump. We simulate 1-, 2-, 3-, and 4-year-long droughts by scaling the observed (2012-2016) 4-year groundwater level change. Due to already low groundwater levels, a simulated a 4-year-long-drought starting in January 2018 would result in more than 4,000 domestic well failures in the Central Valley alone, nearly twice as many well failures compared to 2012-2016. The eastern San Joaquin Valley (especially Fresno, Tulare and Madera counties) and small areas in northern basins are the most susceptible to domestic well failure.

Are disadvantaged households disproportionately affected by drought-vulnerable wells?

To understand the socio-economic conditions of those impacted by well failure, we assign 2016 census block group Median Household Income values to domestic wells located within that block group. We then calculate the distance between failed wells and the nearest community water system. Initial findings indicate that 2012-2016 drought disproportionately impacted domestic wells found in low-income areas.  About 1.5 times more well failures were reported by households in disadvantaged and severely disadvantaged communities (DAC + SDAC together) compared to those at or above the Median Household Income (MHI+).

Additionally, more than half of the well failures in SDACs were less than one mile from the nearest water system, suggesting that connecting households with failed wells to a nearby water system is a potential long-term solution.  Many households with domestic wells that failed are isolated and rural, as shown by the points in this box plot, and anywhere from 2.5 – 7.5 miles from their closest community water system.

Can we identify characteristics of the vulnerable wells that will worsen with climate change?

Results from the spatial model of well failure were used to train an ensemble machine learning classifier on 56 climatic and geologic variables to predict present day well failure across the Central Valley and assess the climatic controls on domestic well failures.  Preliminary results indicate that well failure is associated with higher temperatures in the spring, fall, and summer. This work is ongoing and will be further refined to identify which areas will likely be most at risk in the future; providing information for policymakers and stakeholders to make informed decisions in preparations for the next drought.  

We can’t avoid another drought in California. But we can work to anticipate its potential impacts, plan proactively, and avoid its consequences. Our research provides a framework to deal with one of the worst effects of the latest drought –  thousands of people running out of water in one of the richest regions of the world. Our hope is to show local and state decision-makers what is possible with existing data and methodologies to proactively address drinking water issues in California’s rural communities.

We are grateful to the organizers and champions of the 2018 #CAWaterDataChallenge for their support and recognition of our project.

Rich Pauloo presenting the project (L) and accepting (R) an award for most Data-licious submission and special recognition for the Ready-to-Go award at the Oct 18th award ceremony.

Amanda Fencl is a PhD Candidate in Geography and Rich Pauloo is a PhD Candidate in Hydrology at UC Davis; both are UC Davis NSF IGERT trainees.  Dr. Hervé Guillon is a Postdoctoral Scholar at the UC Davis Water Resources Management Group and Dr. Alvar Escriva-Bou is a Research Fellow at the Public Policy Institute of California.

Read More:

Posted in California Water, Drinking water, Drought | Tagged , | 2 Comments

Getting Strategic about Freshwater Biodiversity Conservation in California

Pacific giant salamander (Dicamptodon ensatus) – The Pacific giant salamander is the largest terrestrial salamander in North America and is one of several salamanders that have vocal abilities.

by Jeanette Howard, Kurt Fesenmyer, Theodore Grantham, Joshua Viers, Peter Ode, Peter Moyle, Sarah Kupferberg, Joseph Furnish, Andrew Rehn, Joseph Slusark, Raphael Mazor, Nicholas Santos, Ryan Peek, and Amber Wright

An essential first step to protect biodiversity is understanding what species are present in a region, where they can be found, and their conservation status. For freshwater organisms in California, this information has been difficult to gather because sampling data are collected by many different entities and have been stored in disparate databases.

But now, a large number of freshwater biodiversity datasets have been assembled to guide strategic conservation planning for the numerous plants and animals that find a home in the state’s rivers, lakes, ponds, and wetlands. “Big Data” has arrived in the form of the PISCES database, which includes range information for all of California’s freshwater fishes; open access to global biodiversity museum records; eBird and other citizen science data collections; and the aggregation of local freshwater bioassessments into the Surface Water Ambient Monitoring Program (SWAMP) database.

To provide a comprehensive inventory of freshwater dependent species, these and other datasets have been compiled into a statewide repository. A new California Freshwater Species Database contains information on 3,906 vertebrates, macroinvertebrates, and vascular plants native to California and that depend on fresh water for at least one stage of their life history. This database has enabled a better understanding of the patterns of freshwater species richness, endemism, and vulnerability in California. The database also provides the foundation for a statewide Freshwater Conservation Blueprint, which for the first time systematically identifies priority watersheds for native freshwater biodiversity management and conservation across California.

Conservation Planning – Putting the Information to Work

Western pearlshell mussel (Margaritifera falcata) – The western pearlshell mussel have life spans up to 100 years and depend on fish hosts for larval development.

Although the loss of terrestrial biodiversity garners much attention, freshwater species are at the forefront of the global extinction crisis. Species dependent on freshwater habitats are in decline globally (Dudgeon et al. 2006) with between 10,000 and 20,000 freshwater species thought to be extinct or imperiled. In California, nearly half of the state’s native freshwater taxa and 90% of the state’s endemic taxa are vulnerable to extinction, with 11 freshwater species considered extinct (1 plant, 2 crustaceans, 1 mollusk, 1 frog, 6 fishes) and 14 possibly extinct (8 insects, 2 amphibians, 1 turtle, 1 mollusk, 2 plants). Moreover, estimates of extinction rates are considered underestimates because freshwater organisms are understudied (Abell 2002).

 Scientists have long been aware that conservation of freshwater biodiversity faces severe challenges. The fragmented nature of freshwater habitats often results in high levels of endemism, making freshwater populations highly vulnerable to extirpation (Strayer and Dudgeon 2010). In addition, efforts to conserve freshwater species are often stymied because protected areas typically reflect jurisdictional/landscape boundaries that have little meaning for aquatic species. For example, an assessment of conservation priority areas for California’s freshwater fishes found that there was little overlap with the state’s existing protected area network (Grantham et al. 2016),  indicating that improved management of both private and public lands is needed to conserve native fish species.

Pacific tree frog (Pseudacris regilla) has a remarkable wide geographic range from Baja to southern British Columbia and inland to parts of Idaho, Nevada and western Montana. This frog is so adaptive that you can find them in your backyard, along the beach, in the Mojave Desert, grasslands and even at 11,000 feet on Mount Whitney.

Efforts to protect freshwater species are often stymied because protected areas typically reflect jurisdictional/landscape boundaries that have little meaning for aquatic species. For example, an assessment of conservation priority areas for California’s freshwater fishes found that there was little overlap with the state’s existing protected area network (Grantham et al. 2016),  indicating that improved management of both private and public lands is needed to conserve native fish species.

Grantham et al.’s effort has recently been expanded to identify watersheds of high conservation value for a broader range of freshwater species. Led by Jeanette Howard of The Nature Conservancy in collaboration with scientists from the state, federal, academic, and NGO community, we used a conservation planning tool to identify an efficient network of priority conservation watersheds for California’s fishes, frogs, salamanders, snakes, and turtles – the ‘target taxa’. The planning tool first identifies watersheds where the majority of land area or perennial stream mileage has a management mandate emphasizing biodiversity – ‘existing protected areas’ such as national parks – and then incorporates a network of additional watersheds where the most taxa co-occur and where rare taxa are present.

Priority conservation areas. The network is comprised of watersheds with a fish, amphibian or reptile target species present and at least 75% of the watershed area or stream network in a protected area (USGS Gap Analysis Program status 1, 2; green watersheds), and watersheds that best complement these protected areas based on species present (purple watersheds). The network is constructed in a way that maximizes the number of species and proportion of those species’ ranges included, while minimizing the area of the network.

The assessment was recently published in an article in Freshwater Science (Howard et al. 2018) and outlines a Freshwater Conservation Blueprint for California. The Blueprint delineates a comprehensive, representative, and efficient freshwater conservation network that covers around 1/3 of the land area of California (Figure 1) – yet includes at least 10% of the range of all target taxa.  This area is comparable in size to existing protected areas, but provides more “bang for the buck” in conserving freshwater biodiversity because many target taxa are absent from existing protected areas.

More importantly, ~70% of the freshwater conservation network occurs on public lands managed for multiple purposes such as grazing, logging, and recreation.  These lands are largely those of the US Forest Service and Bureau of Land Management, where small changes in management could provide substantial benefits to freshwater biodiversity.

The Blueprint provides strong evidence for compatible management of aquatic biodiversity on multi-use public and private lands. Maps of priority conservation areas are available online via California Department of Fish and Wildlife’s BIOS tool, and we have developed an online decision support tool for evaluating impairments, threats, and potential conservation actions within the priority areas.

How This Blueprint Can Be Used

The goals of the Freshwater Blueprint for California are to help improve the efficiency of on-going and planned conservation efforts and accelerate progress towards effective, long-term preservation of the state’s freshwater biodiversity.

Longhorn fairy shrimp (Branchinecta longiantenna) – an federally listed endemic crustacean to California where there are only four known populations.

The proposed conservation network is intended to identify watersheds where management actions can be prioritized to conserve native freshwater biodiversity. We don’t envision the state establishing a new reserve network – rather, the objective is to create a more coherent and targeted approach to freshwater conservation.

Limited resources require strategic action to conserve freshwater taxa currently represented within protected areas and to preserve biodiversity hotspots that primarily occur outside reserve boundaries. Because priority catchments within and outside protected areas are threatened by climate change and other stressors, conservation will require reconciliation approaches to create the best possible conditions for freshwater fishes in altered environments within existing management regimes (Moyle 2013).

There is growing evidence that conservation of freshwater biodiversity is compatible with human uses. For example, efforts to restore flows in Putah Creek via dam releases and the Shasta River through changes in agricultural irrigation practices have resulted in improved conditions for native fishes without adversely affecting primary human uses. Restoring floodplain connectivity in human-dominated landscapes through managed floodways, offseason flooding of fields, or active levee breaching, have been shown to provide multiple ecosystem benefits, reduce flood risk, and sustain floodplain agriculture. By guiding the strategic implementation of such management approaches, the Freshwater Conservation Blueprint can help bring ecosystem reconciliation to scale and ensure the long-term preservation of the state’s freshwater biodiversity.

We emphasize that while the Blueprint lays the broad groundwork for a conservation strategy, it is not meant to diminish more localized conservation efforts that are outside the designated areas.  All the species covered by the Blueprint need multiple populations to thrive. Thus, smaller refuges outside those designated in the Blueprint are always important.  This is one reason why statewide monitoring programs are needed to continually expand and update the database to track the changes in the range and abundance of freshwater species. With good data and a strategic approach, we can reverse the trends of biodiversity loss and safeguard the future of our state’s freshwater species.

Jeanette Howard is the Director of Science for the Water Program at the Nature Conservancy. Kurt Fesenmyer is the GIS and Conservation Planning Director with Trout Unlimited. Ted Grantham is faculty at the University of California, Berkeley, and an affiliate of the U.C. Davis Center for Watershed Sciences. Josh Viers is faculty at the University of California, Merced, and an affiliate of the Center for Watershed Sciences. Peter Ode is affiliated with the Aquatic Bioassessment Laboratory at the California Department of Fish and Wildlife. Peter Moyle, Nicholas Santos, and Ryan Peek are affiliates of the Center for Watershed Sciences. Sarah Kupferburg is with Questa Engineering. Andrew Rehn and Joseph Slusark are affiliates of the Aquatic Bioassessment Laboratory, California Department of Fish and Wildlife, and Center for Water and the Environment—California State University, Chico. Raphael Mazor is affiliated with the Southern California Coastal Water Research Project. Amber Wright is faculty at the University of Hawaii, Manoa.

Further reading

Howard JK, et al. 2018. A freshwater conservation blueprint for California: prioritizing watersheds for freshwater biodiversity. Freshwater Science. 37(2):417-31.

Strayer DL, Dudgeon D. 2010. Freshwater biodiversity conservation: recent progress and future challenges. Journal of the North American Benthological Society. 2010; 29: 344–358.

Dudgeon D et al. 2006. Freshwater biodiversity: importance, threats, status and conservation challenges. Biological Reviews. 81: 163–182.

Abell R. 2002. Conservation biology for the biodiversity crisis: a freshwater follow-up. Conservation Biology. 16(5): 1435–1437.

Grantham, TE, et al.  2017. Missing the Boat on Freshwater Fish Conservation in California. Conservation Letters. 10: 77-85.

Howard JK, et al. 2015. Patterns of Freshwater Species Richness, Endemism, and Vulnerability in California. PLoS ONE. 2015; 10(7): e0130710.

Moyle, P.B. (2013). Novel aquatic ecosystems: the new reality for streams in California and other Mediterranean climate regions. River Res. Appl., 30, 1335-1344.

Posted in Biology, California Water, Conservation, reconciliation | Tagged | 1 Comment

U.C. Davis Law’s Environmental Law Center Releases Proposition 3 White Paper

by Richard Frank

This article originally appeared on Legal Planet on October 31, 2018

The U.C. Davis School of Law’s California Environmental Law & Policy Center has published a detailed analysis of one of the most controversial initiative measures facing California voters on the November 6, 2018 general election ballot: Proposition 3.  California’s Proposition 3: A Policy Analysis provides a detailed summary and analysis of the proposed “Water Supply and Water Quality Act of 2018.”  If enacted, Proposition 3 would authorize the sale of $8.877 billion in state general obligation bonds to finance a wide array of water infrastructure, safe drinking water, groundwater management and watershed and fisheries improvement projects.  (When interest payments are included, the cost to California taxpayers of this proposed water bond measure would be an estimated $17.3 billion.)

The new white paper, authored by 2018-19 CELPC Environmental Law Fellow Sunshine Saldivar (King Hall `17), includes a background discussion on recent California’s state spending on water projects; the impetus for Proposition 3; how this initiative measure was developed and placed on the general election ballot; a detailed explication of the six different categories of water projects that Proposition 3 would fund if passed into law; a discussion of the measure’s key “water justice” component; and a summary of the arguments advanced by both proponents and opponents of Proposition 3.

Supporters of Proposition 3, led by its principal author, Jerry Meral (a former senior water and natural resources advisor to California Governor Jerry Brown and prior executive director of the Planning and Conservation League), argue that investment in California’s crumbling water infrastructure is desperately needed to help secure the state’s future water supply in future years.  Proposition 3’s advocates further contend that substantial new funding is required to ensure that California’s disadvantaged communities gain greater access to safe drinking water.  Finally, they stress that the proposed bond measure would fund an array of needed environmental benefits for watershed lands and critical fish and wildlife habitat.

Proposition 3’s opponents, on the other hand, have several criticisms of the measure.  First, they argue that the initiative measure lacks transparency because the measure was developed and drafted “behind closed doors” and placed on the ballot through the signature-gathering process rather than (as is the case with most bond measures coming before the votes) first being debated and enacted by the California Legislature.  A related criticism is that Proposition 3 is a so-called “pay-to-play” measure, because private groups allegedly provided funds to support the initiative’s campaign in exchange for receiving funding from the water bond proceeds.  Finally, opponents contend that Proposition 3 would provide taxpayer funding to numerous water infrastructure projects that they believe should instead be paid for by those, like corporate agricultural interests, who stand to benefit directly and disproportionately from those infrastructure projects.

Notably, California’s political leaders, newspaper editorial boards and environmental groups are divided regarding the merits of Proposition 3.  Supporting the water bond measure are U.S. Senator Feinstein, State Senate President Pro tem Toni Atkins, newspapers from California’s major agricultural regions and the League of California Cities, California Chamber of Commerce, the Nature Conservancy and Ducks Unlimited.  Opponents of Proposition 3 include State Assembly Speaker Anthony Rendon, most of California’s major urban newspapers, the League of Women Voters of California, the Sierra Club, Friends of the River and the Southern California Watershed Alliance.

The full text of Proposition 3 can be found here; the official title, summary and fiscal analysis of the initiative measure, together with formal arguments submitted to voters by designated proponents and opponents of Proposition 3, can be found here.

California’s Proposition 3: A Policy Analysis is not an advocacy document.  Rather, CELPC’s goal is to provide a nonpartisan, objective analysis of this major initiative measure in order to better inform California voters and interested observers, and thereby help elevate the public dialogue concerning water and fiscal issues affecting every Californian.

Richard Frank is Professor of Environmental Practice and Director of the U. C. Davis School of Law’s California Environmental Law & Policy Center. From 2006-2010, he served as Executive Director of the Center for Law, Energy & the Environment and as a Lecturer in Residence at the U.C. Berkeley School of Law. Frank’s particular research interests include climate change law and policy; water in the American West; environmental governance questions; property rights and the environment; and coastal and oceans policy.

Further reading

U.C. Davis California Environmental Law & Policy Center. 2018. California’s Proposition 3: A Policy Analysis.

Posted in California Water | Tagged , , | 2 Comments

Opportunities for Science Collaboration and Funding in the Delta

Delta data station (2)

by Aston Tennefoss

The Sacramento-San Joaquin Delta (Delta) is central to California’s water supply system, and serves a diverse group of stakeholders, including local, state, and federal agencies, elected officials, and water users. Its islands, channels, and wetlands also are home to an expansive but highly disrupted ecosystem, which is studied extensively. Many studies are done to meet regulatory obligations or to inform management decisions. Because many organizations make up the Delta science enterprise, there are multiple approaches and reasons for this science, as well as highly variable funding.

As part of the master’s program in Environmental Policy and Management at the University of California, Davis, I examined whether a path to shared funding to promote shared decision-support science exists for the Delta. My research involved a literature review, attending meetings relevant to Delta science, and 23 interviews with individuals from federal and state water, agricultural, and environmental agencies as well as non-governmental organizations and interests. The full report, found here, was provided as a white paper for completion of a volunteer practicum with the office of the Delta Watermaster at the State Water Resources Control Board.

The study evaluated current collaborative Delta science and its funding to identify gaps between the current organization of science and underachieved policy aspirations for science. It also identified barriers to funding and collaboration for scientific research on the Delta. Finally, the report recommends opportunities to overcome existing barriers and to move to more reliably funded and efficiently organized interagency science. A summary of the report’s seven recommendations follows:

  1. Implement stronger coordination of science across agencies. Existing fragmentation of mandates and efforts among agencies hampers collaboration and efficiency. Creating opportunities for improved collaboration requires a governance structure including decision-makers and scientists. Several options are available to strengthen science coordination and integration across agencies. Such arrangements should promote trust, provide actionable authority, and maintain agency sovereignty.
  1. Establish a competitive and targeted incentive grant fund through the state budget act, to provide matching resources for research and technical partnerships across agencies, and between agencies and other qualified entities. Such grants, administered by the Delta Science Program, would match State agency funds for collaborative studies aligning with the Science Action Agenda and/or Delta Science Plan. By requiring data management and reporting consistent with the Open and Transparent Water Data Act, these grants also would advance the open data legislative mandate while promoting One Delta, One Science – an efficient use of general funds to leverage consistent funding from both State and non-State sources.
  1. Provide ongoing, consistent long-term funding for adaptive science to inform Delta restoration projects as part of adaptive management programs, Eco-Restore, and other mitigation and restoration programs. Adaptive management programs are a proving ground for science and management; funds for capital projects should include a percentage for ongoing synthesis, analysis and evaluation of project actions. These projects directly align with the co-equal goals of enhancing the Delta ecosystem and water supply reliability. Monitoring and learning from these projects would constitute a tangible general fund commitment to those long-term priorities.
  1. Develop funding for critical synthesis from existing data, with priority of projects and agency co-lead responsibility. Regulatory requirements drive agencies to focus on data collection and reporting, supporting little analysis of how the data can aid decision-making. Agency scientists, when given synthesis priorities and a regular management audience, are better positioned to identify trends in existing data and opportunities for actions that will be evaluated against measurable objectives and outcomes.
  1. Allocate science priorities based on agency and stakeholder areas of expertise, capacity, and jurisdiction. Science priorities span a diverse range of topics and action areas. For each priority to be addressed, actions should be allotted among agencies and stakeholders to achieve full breadth of coverage, take advantage of existing efforts, harness experienced leaders, and respect jurisdictional boundaries. No one agency or stakeholder can achieve all science priorities independently or integrate findings effectively to inform decision-making across agencies.
  1. Establish a regular system of workgroups and discussions to bring science and policymakers together. Examples of science gatherings and policy gathering abound but, separation of science and policy discussions is the norm. The value of science for policy cannot be realized if its relevance is not communicated regularly and succinctly to managers. Science and policy interactions promote new ideas for both science and policy.
  1. Seek federal funding for science priorities across the Bay-Delta. Trillions of dollars in economic output are tied to Bay-Delta water, which directly affects the national and global economy. The federal government has an economic interest in the continued viability of the Bay-Delta water supply and ecosystem. Federal funding for Bay-Delta science and projects throughout the entire Delta watershed should be comparable to that for other major national estuaries.

Guidance from the Delta Stewardship Council and Delta Science Program already has moved the science enterprise toward greater integration and collaboration. A recovered estuary will provide broad societal benefits to stakeholders across California and an accountable science enterprise can inform this recovery; therefore, long-term financial support for Delta science is in the public interest. Commitment of tax revenue to match the resources of agencies, water users, and NGOs, processes can support future science and enable more frequent, trust building, transboundary engagement to better inform management decisions.

Aston Tennefoss ( completed this work as a practicum for his Masters in Environmental Policy and Management at the University of California – Davis, working with the Delta Watermaster.  He is the program’s first graduate.  The opinions he expresses are his own.

Further reading

Delta Stewardship Council. The Science Enterprise Workshop: Supporting and Implementing Collaborative Science. Davis, CA. 2016.

Gray, B., Thompson, B., Hanak, E., Lund, J., & Mount, J. Integrated Management of Delta Stressors: Institutional and Legal Options. San Francisco: Public Policy Institute of California. 2013.

Mearns, A.J., Allen, M.J., & Moore, M.D.; S.B. Weisberg, D. Elmore, eds., The Southern California Coastal Water Research Project – 30 years of environmental research in the Southern California Bight. Westminster, CA: Southern California Coastal Water Research Project, 2001.

Mount, J. Advice on Voluntary Settlements for California’s Bay-Delta Water Quality Control Plan Part 3: Science for Ecosystem Management. California WaterBlog. 27 February 2018.

Tennefoss, A. Shared Science for the Sacramento-San Joaquin Delta. Environmental Policy and Management MS practicum paper, University of California, Davis. October 2018.


Posted in Delta, Planning and Management, Sacramento-San Joaquin Delta, Uncategorized | Tagged | 1 Comment

The Public Trust and SGMA

by Brian Gray

A recent court ruling about the Scott River has prompted questions about SGMA and the public trust doctrine.

In a recent decision in litigation over flows and salmon survival in the Scott River system, the California Court of Appeal has ruled that groundwater pumping that diminishes the volume or flow of water in a navigable surface stream may violate the public trust. The public trust does not protect groundwater itself. “Rather, the public trust doctrine applies if extraction of groundwater adversely impacts a navigable waterway to which the public trust doctrine does apply.” The court also concluded that the Sustainable Groundwater Management Act (SGMA) does not preempt or preclude independent application of the public trust to groundwater pumping, finding “no legislative intent to eviscerate the public trust in navigable waterways in the text or scope of SGMA.”

These interpretations follow from both hydrology and law. If groundwater extraction diminishes stream flows and jeopardizes public trust uses—which include water quality, fish and wildlife, recreation, and other instream uses—it should be treated the same as surface diversions that have similar effects. This is also consistent with the California Supreme Court’s landmark decision in the Mono Lake case. In National Audubon Society v. Superior Court (1983), the court recognized the public trust as a limitation on Los Angeles’ diversions of water from nonnavigable tributaries, because those diversions harmed public trust uses in the navigable lake downstream.

Moreover, if the public trust was not displaced by the modern statutory water rights system generally, as the Supreme Court held in Audubon, it should not be displaced by a more specific law such as SGMA—unless the legislature manifested its intent to preempt the public trust or other aspects of California water rights law. Indeed, SGMA says just the opposite, declaring that nothing in the statute or any groundwater sustainability plan “determines or alters surface water rights or groundwater rights under common law or any provision of law that determines or grants surface water rights.”

The Scott River Decision and SGMA Implementation

Although the court of appeal’s opinion makes clear that the public trust applies independently of SGMA, the Scott River decision nevertheless will influence the formulation and implementation of groundwater sustainability plans (GSPs). At a minimum, the decision should focus groundwater sustainability agencies and groundwater users on SGMA’s directives to avoid “depletions of interconnected surface water that have significant and unreasonable adverse impacts on beneficial uses of . . . surface water” and to address the effects of pumping on groundwater dependent ecosystems in their sustainability plans. (Water Code §§ 10721(x)(6) & 10727.4(l)) The overriding concern of most GSAs will be to manage demand and available recharge to achieve sustainable aggregate pumping levels by their members as required by SGMA. This presents a risk that they will downplay other aspects of sustainability, including prevention of injury to public trust uses. The Scott River decision changes this dynamic.

The decision also affects the timeframe for remediating harm to public trust uses of hydrologically connected, navigable rivers or lakes. SGMA requires GSAs to develop and implement plans that achieve sustainability within a 20-year (or longer) period.  Under the new decision, however, a claim to enjoin groundwater pumping that impairs the public trust may be brought at any time. In adjudicating these claims, the State Water Board and the courts are likely to consider—and give some deference to—the GSP’s strategy and timeline for addressing harm to surface resources. But neither would be bound or limited by the terms of the sustainability plan.

Public trust claims are subject to different standards than those that apply under SGMA however, and these differences cut in both directions. For example:

  • The public trust only protects navigable rivers and lakes. Therefore, the Scott River decision will not affect groundwater pumping that harms wetlands or nonnavigable streams—unless the harm manifests itself downstream in a navigable body of water. In contrast, SGMA’s directives extend to all types of groundwater extraction and surface water resources.
  • In Audubon, the state Supreme Court held that the public trust doctrine requires water users to protect public trust uses to the extent feasible. This requires an assessment of the feasibility of restoring and protecting the surface resource, as well as consideration of the water users’ alternative sources of supply, demand reduction capabilities, efficiency improvements, and cost considerations. In contrast, SGMA’s sustainability mandate does not include a feasibility criterion.
  • The public trust requires restoration and maintenance of groundwater levels and surface water flows as needed to afford reasonable protection of public trust uses. By comparison, SGMA provides that GSAs are not required to address “undesirable results” that occurred before January 1, 2015, such as harm to beneficial surface water uses. No such baseline or statute of limitations applies to public trust claims.

The Scott River Decision and Water Management

With these principles in mind, the Scott River decision will likely play out in mixed ways across California.

First, there are many watersheds where groundwater discharges feed headwaters and tributaries or the groundwater table supports the rivers themselves. This occurs throughout the Sacramento-San Joaquin River system, in many coastal streams, and in the rivers of the Tulare Basin above the rim dams where more than two-thirds of stream discharges come from groundwater. When river flows run low and threaten public trust uses, the Scott River decision will extend remediation and protection responsibilities to surface diverters and groundwater extractors alike.

Second, hydrologic studies have demonstrated that, in some systems, groundwater pumping is a significant cause of stream flow reduction that harms fish. These include: the Cosumnes River, where late season diversions and groundwater pumping imperil fall-run Chinook salmon; the Russian River, where pumping from aquifers that support the river and its tributaries has placed coho salmon in jeopardy; and the Scott River itself, where groundwater overdraft has reduced late summer and fall stream flows and raised surface water temperatures to the detriment of Chinook salmon, coho, and steelhead. The public trust is likely to play a significant role in these systems.

Third, there are regions where the hydrologic connection between groundwater and navigable rivers and lakes was lost long ago. On the valley floor of the Tulare Basin, for example, sustained groundwater overdraft for many decades has lowered the groundwater table by hundreds of feet. Because restoration of the hydrologic connection would require drastic long-term reductions in groundwater extraction and water use, it is unlikely that the State Water Board or the courts would find that such restoration is feasible under the standards set forth in Audubon.

Finally, there are systems where local water users and other interested parties are working to restore and protect stream flows, wetlands, riparian vegetation, and other groundwater dependent ecosystems. Although many of the groundwater dependent ecosystems in these systems do not qualify as navigable waters, they often feed into and support navigable rivers. To the extent that pumping adversely affects public trust uses in such surface waters, groundwater extractors may be called on to contribute to system-wide solutions. Examples include: the Oxnard Groundwater Subbasin, where the Fox Canyon Groundwater Management Agency is working with The Nature Conservancy to improve water supplies for six groundwater dependent ecosystems that are tributary to the Santa Clara River; and the Los Angeles River system, where the City of Los Angeles is working with Friends of the LA River to revitalize the river by removing concrete, restoring riparian zones, controlling stormwater inflows, and creating infiltration areas to improve groundwater conditions that support the river.


The Scott River decision places new responsibilities on GSAs and groundwater users, and it increases the legal leverage of those who seek to restore and protect groundwater dependent rivers and ecosystems. Yet, the decision need not lead to more litigation.

Rather, GSAs with responsibility over groundwater that has (or feasibly could have) a hydrologic connection with surface water resources should incorporate public trust analysis into their sustainability plans. They should work with experts in groundwater-surface water hydrology and ecological sciences, and they should partner with pubic trust advocates. The Fox Canyon and LA River collaborative restoration programs are useful examples.

Incorporation of public trust analysis into relevant GSPs offers several advantages over public trust litigation. Sustainability plans are more comprehensive, because they must include evaluation of the effects of groundwater pumping on all beneficial uses of surface water and groundwater dependent ecosystems, not just on public trust uses of navigable waters. The plans also can provide a vehicle for integrated management that includes floodplains, wetlands, riparian zones, and connected surface waters, as well as regulation of groundwater pumping and deployment of surface water recharge. And GSP formulation can be a collaborative process that engages all interested parties, rather than pitting them against one another. Indeed, every successful public trust lawsuit to date has culminated in a negotiated settlement that folds the public trust remedies into a broader, multifaceted restoration and long-term management program.

The State Water Board or the Department of Water Resources should facilitate these studies by providing guidance on protecting and remediating harm to public trust uses within the framework of groundwater sustainability plans. The Department of Fish and Wildlife and DWR should offer technical support. DWR also should make clear that its formal GSP review will include evaluation of the plan’s analysis of the effects of groundwater extraction on waters protected by the public trust and its strategy for addressing harm to public trust uses.

Brian Gray is a Senior Fellow at the Public Policy Institute of California Water Policy Center and a Professor Emeritus at UC Hastings.

Further Reading

Belin, Alletta. 2018. Guide to Compliance with California’s Sustainable Groundwater Management Act. Water in the West, Stanford University.

California Department of Water Resources. 2018. SGMA Groundwater Management: Best Management Practices and Guidance Documents.

Alida Cantor, Dave Owen, Thomas Harter, Nell Green Nylen, and Michael Kiparsky. 2018. Navigating Groundwater-Surface Water Interactions under the Sustainable Groundwater Management Act. Center for Law, Energy & the Environment, UC Berkeley School of Law.

Jan Fleckenstein, Michael Anderson, Graham Fogg, and Jeffrey Mount. 2004. “Managing Surface Water-Groundwater to Restore Fall Flows in the Cosumnes River.Journal of Water Resources Planning and Management. Vol. 130, No. 4, pp. 301-10.

Richard Frank. 2018. “California Court Finds Public Trust Doctrine Applies to State Groundwater Resources. Legal Planet, Aug. 29, 2018.

Brian Gray. 2012. “Ensuring the Public Trust. U.C. Davis Law Review, Vol. 45, pp. 973-1019.

Jeanette Howard and Matt Merrifield. 2010. “Mapping Groundwater Dependent Ecosystems in California.PLOS One, June 23, 2010.

Melissa Rohde, Sandi Matsumoto, Jeanette Howard, Sally Liu, Laura Riege, and E. J. Remson. 2018. Groundwater Dependent Ecosystems Under the Sustainable Groundwater Management Act: Guidance for Preparing Groundwater Sustainability Plans. The Nature Conservancy, San Francisco.

The Nature Conservancy. 2018. Groundwater Resource Hub: Understanding and Managing Groundwater Dependent Ecosystems.

Posted in California Water, Groundwater | Tagged , , , , | 6 Comments

Water storage successes, failures, and challenges from Proposition 1

by Jay Lund

A rendering of Sites Reservoir, one of the proposed storage projects under Prop 1. (Source: KVCR)

The California Water Commission recently allocated $2.7 billion from Proposition 1 bonds for eight water storage projects.  Proposition 1 was passed in 2014 to fund a range of projects, including “public purposes” of water storage projects, such as for ecosystem support, flood risk reduction, water quality, recreation, and emergency response.  Among its many funding provisions, both surface and underground water storage projects were eligible, non-storage projects were not eligible, and Proposition 1 could fund no more than 50% of storage project costs.

Proposition 1’s storage provisions were driven by the still-common notion that expanding surface storage is the major way to end water problems. This idea has long myth-directed policy and public discussions.  The competition for Proposition 1 funds indicates that few large surface water storage expansions are cost-effective in California.

Completing all Proposition 1-funded storage projects would increase total surface water storage capacity in California by less than 8 percent, and increase water deliveries by perhaps 1-2 percent, because most of the expanded capacity would refill infrequently.  New storage capacity will be useful, but usually has a low and decreasing incremental value for water users and other beneficiaries. The Proposition 1 water storage program could easily be the last hurrah for major expanded surface water storage in California.

Nevertheless, this process has shown some successes, failures, and challenges for state water infrastructure bonds, and water development in California more generally.


Remarkably, it took only four years for this bond fund allocation to be made by a nonpartisan independent commission for some fairly large complex projects. The Commission involved insisted effectively that projects be well justified and competitively compared.  When money is being given away, everyone feels worthy to receive, but the Commission seems to have allocated this $2.7 billion to relatively cost-effective and promising water storage projects.  The California Water Commission, long mostly dormant, became an effective institution.

Another major success of the Proposition 1 process is that it brought more creativity to project proposals.  The program brought proposals of many sorts, both surface and groundwater storage, from many parts of the state.  And the commission allocated funds to a diverse set of the most promising projects scattered across California.

The state could have done much worse.  However, it will take years more to complete these projects, and some projects may never be completed.  Building major projects has always been a long road.


Proposition 1 general revenue bonds are to be repaid with general state tax revenues.  At 5% interest, this $2.7 billion in bonds implies about $135 million/year in decreased state general revenues available for every other state government responsibility, including education and public health, as well as environmental and water management more generally.  Although public benefits will come from these storage projects, in many cases these benefits are likely to be less than the broader public benefits of less-restricted government investments.

A few projects will receive the bulk of these state subsidies.  Beneficiaries include state and local agencies and groups receiving these project’s public benefits.  But because only storage projects were eligible for funding, other non-storage water projects are likely to provide similar public benefits at less expense.


Although partial state funding has been secured, projects now must secure substantial water user funding.  Modern water supplies rely on a “portfolio” approach, mixing a diversified water supply system and diverse efforts to reduce water demands.  This approach greatly reduced the costs of the recent drought to urban and agricultural water users.  The partially state-funded storage projects will need to compete with other potential water utility portfolio investments for their remaining funding.

The water storage projects, especially the larger ones, also must work within the limitations of existing water availability, water rights priorities, environmental regulations, and limited conveyance capacities. Most water storage projects will require water right, environmental, and operation agreements with a host of other agencies and interests.  This will be a challenge, but brings possibilities for improving system operation overall, where agreements can be made. Such negotiations are often protracted. Upgrading California’s water system has always been negotiation-intensive (and expensive).  This is probably unavoidable, but does need to be better organized and expedited.

Time will tell if these projects will attract sufficient non-state funding, permits, and coordinating agreements for their completion.  Some will, and probably some won’t.

State infrastructure policy should be concerned with local and regional balancing of supply and demand management based on performance and costs.  Proposition 1 has brought mixed progress overall in this regard, while catering to a common misconception that storage is the major water limitation statewide. Current and future storage expansions should be narrowly targeted to be cost-effective and fit well within the larger system.

Jay Lund is the Director of the Center for Watershed Sciences.

Further reading

Sites bond funding decided this week”, Chico Enterprise-Record, 23 July 2018

California Water Commission, Proposition 1 Water Storage Investment Program: Funding the Public Benefits of Water Storage Projects,

Hanak, E., J. Lund, A. Dinar, B. Gray, R. Howitt, J. Mount, P. Moyle, and B. Thompson, California Water Myths, Public Policy Institute of California, San Francisco, CA, Dec. 2009.

Lund, J., A. Munévar, A. Taghavi, M. Hall and A. Saracino, “Integrating storage in California’s changing water system,” Center for Watershed Sciences, UC Davis, 44 pp., November 2014.

Lund, J.R., J. Medellin-Azuara, J. Durand, and K. Stone, “Lessons from California’s 2012-2016 Drought,” Journal of Water Resources Planning and Management, October 2018.

Posted in California Water, Uncategorized, Water Supply and Wastewater | Tagged , , | Leave a comment

Water Grabs of California, Explained Simply

by Jay Lund

California Water Grabs explained simply 2

Your water use is a “grab” and a “waste.”  My water use is a nab, and a sacred right.  We all see water the same way, mostly, but from different perspectives.

Historically, periods of progress in water management occur when enough people rise above such motivational rhetoric and struggle for workable solutions.

Further reading

Hanak, E., J. Lund, A. Dinar, B. Gray, R. Howitt, J. Mount, P. Moyle, and B. Thompson, Managing California’s Water:  From Conflict to Reconciliation, Public Policy Institute of California, San Francisco, CA, 500 pp., February 2011.

Kelley, R. 1998. Battling the Inland Sea. Berkeley: University of California Press.

Pisani, D. 1984. From the Family Farm to Agribusiness: The Irrigation Crusade in California, 1850–1931. Berkeley: University of California Press.

Jay Lund is a Professor of Civil and Environmental Engineering, University of California – Davis. 

Posted in Uncategorized | 7 Comments