Data Drought: Could Better Information Help Resolve Longstanding Conflicts Over Delta Water?

• Publication year: 2015
• Author: by Colleen Flannery

Data Drought: Could Better Information Help Resolve Longstanding Conflicts Over Delta Water?

by Colleen Flannery^*

When Delta farmers recently volunteered to cut by one quarter the amount of water they will use to irrigate their crops,¹ some quickly labeled it a "white flag" in California's water wars.² But the extraordinary gesture instead could be seen as a red flag forewarning of even more intense conflicts to come in the Sacramento-San Joaquin River Delta.

The Delta supplies a portion of the water for 25 million Californians, as well as the water that irrigates three million acres of farmland.³ For the fifth straight year, freshwater flows into the Delta have been in drought conditions, exposing deep flaws in an exports system premised on wetter years. These flaws appear most starkly where in-Delta water users, who mostly divert under riparian or pre-1914 senior water rights, square off against those who rely upon Central Valley Project (CVP) and State Water Project (SWP) flows.

The CVP-SWP exporters in 2014 and 2015 filed complaints alleging improper in-Delta diversions while maintaining their own right to use previously stored water. The State Water Resources Control Board ("State Water Board") responded to that complaint by requiring in-Delta users to submit paper evidence proving their water rights, and has begun unprecedented curtailments of Delta riparian and senior appropriative water rights.⁴

But an unaltered Gold Rush-era doctrine regarding the determination of the burden of proof in cases of commingled water places the burden of proving a right to continue to use the stored water upon the exporters.

This article: I) discusses how the drought affects the Delta, and the rights of in-Delta diverters, exporters, and fisheries within the entire Delta system; II) describes the pragmatic burden-of-proof requirement that must be applied to exporters who use the Delta as a natural channel to convey previously stored water; and, III) examines the evolution in the way the State views the availability of Delta water. To prepare the Delta to best address future droughts, the article also will: IV) propose holding in-Delta users, water exporters, and fisheries simultaneously responsible for providing better information about water use, water storage, precipitation, and flows in order to assist in water allocation decisions affecting the Delta during future droughts.

I) DROUGHT IMPACTS IN THE DELTA

The Sacramento-San Joaquin River Delta provides just 13 percent of the water used in the State⁵—yet this embattled area is the center of California's "water wars" even in normal and wet years. This is in part because of the hydrogeologic features of the Delta, and partly due to the unique nature of California's water rights system.

i) Background: Water, Water Everywhere, But Not a Drop to Spare

From the deck of a boat on the Delta, the drought may seem a matter of semantics. Traditionally, a "drought" requires a water shortage. But there is always water in the Delta—even five years into California's drought emergency, as the amount of snowpack and freshwater flows in the system hit historic lows.⁶

This is because in the Delta, as in the poem The Rime of the Ancient Mariner,⁷ water is everywhere, but fresh water can be hard to find.⁸ In the Delta, fresh water outflow from snowpack and rainfall collide with saltwater inflow borne by the tides, keeping the brackish inflow at bay. Normally and in wet years, freshwater outflows from rain and snowmelt repel the inflow of salt water, preventing it from intruding into the Delta. However, beginning in January 2014, dry conditions meant that the water in the South Delta began to reach salinity levels unsafe for human health, farming, and fisheries.⁹

With tens of millions of Californians dependent on the Delta for clean drinking water, the creeping salinity presents a real problem. Even more concerning, once salinity overtakes the Delta, vast amounts of flushing flows are required to push back its intrusion.¹⁰ These flows also recharge the groundwater basins underlying the Delta.¹¹

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Importantly, a recent study of historic conditions shows that the Delta has not received a pulse of these flushing flows for many years.¹² The 2010 Contra Costa Water District study probed available data, including studies of tree rings and nineteenth-century historical records. The exhaustive study found that "[s]alinity intrusion begins earlier in the year, extends farther upstream, and persists for a longer period each year."¹³ For instance, salt water intrudes between 3 and 15 miles up into the Delta more than it used to.¹⁴ Looking at historical patterns, the salinity in half the years preceding the 2010 study exactly mirrored dry-year conditions—even though some of those years were wet years.¹⁵ Finally, the "flushing flows" that scoured salinity after the 1930s drought have failed to replenish the Delta following more recent droughts.¹⁶

Acting as living barometers, the fish that spawn and swim in the Delta and its tributaries perhaps suffer the most from the salinity and temperature. An entire generation—some 95 percent—of winter-run salmon, which spawn in the upper Sacramento River, died in 2014.¹⁷ Populations of Delta smelt, which require less saline water to spawn,¹⁸ also have plummeted, and fisheries scientists and agencies warn of imminent extinction for these tiny fish.¹⁹ This population slump occurred even as management of salinity levels to protect fish moved to the center of the State's water management strategy.²⁰

In recent years, California's Delta thus has remained in a state of drought that harms fish and impairs the region's ability to recover and replenish its supply of fresh water each year. Because the Delta does not recover from past intrusions for many years, drought years harm the Delta over the immediate and long term.

ii) The Delta, Area of Origin, and California Water Rights

But why does the Delta remain in this state? Diversions.

In-Delta diversions for farming and related uses began in the nineteenth century. Beginning in 1951 and increasing through the 1970s and beyond, the State Water Project and Central Valley Project began diverting millions of acre-feet of water per year. Now, natural water flows that formerly freshened the Delta are stored in reservoirs during the wet season for later release and export.

Water that flows through the Delta benefits three separate interests: a) in-Delta diverters; b) exporters, who commingle their stored flows with the natural Delta flows; and, c) the Delta's declining fisheries. Each possesses their own unique claim to these flows.

a) Water for In-Delta Diverters

In the nineteenth century, a system of levees—earthen dams, really—and drainage canals began to reclaim the "Inland Sea" into one of the world's most fertile farming areas.²¹ Despite these modifications, the islands that make up the Delta remain the same as those that made up the historic Delta. And in-Delta riparian and senior appropriative water rights holders continue to divert its waters as they did when the Delta had fewer demands.

In California, as in other Western states, riparian water users are those who divert natural flows from a natural watercourse.²² The rights of these riparian water rights holders are generally superior to those who hold appropriative rights—i.e., those who have appropriated natural flows from a watercourse.²³ Appropriative rights, including the senior water rights held by many in-Delta diverters, are administered via a "first in time, first in right" method.²⁴ Holders of older rights claim their share before newer rights, and the State Water Board may prioritize some beneficial uses over others.²⁵

Neither the holders of riparian water rights nor those claiming a pre-1914 right to appropriate water must obtain a State Water Board permit to divert water, although these users must quantify and report their diversion amounts.²⁶

Like all California riparian water rights holders, in-Delta holders of riparian water rights may divert the natural flows from the natural watercourse that feeds their water right, but they may not store water,²⁷ divert water unreasonably,²⁸ or divert stored water known to be reserved for others.²⁹ As the State Water Board puts it, "The rights of users of water on riparian lands and appropriators in the Delta extend only to water quality and quantity which would have existed in the absence of the projects, taking into consideration current upstream uses under vested rights."³⁰

Further, since 1983, all water rights must give way before the public trust, because no water rights holders can attain a vested right to divert water in a manner that harms the public trust.³¹

In-Delta diverters do receive special protection from the Area of Origin statutes, which require an "adequate" supply of water for in-Delta users and bar diversions of water needed to control salinity. ³² However, the statutes specify neither what constitutes an "adequate" supply, nor what water is needed for salinity control.³³ Area of Origin statutes do not enable in-Delta water users to divert stored water released by the Projects,³⁴ or to use water owed to upstream users under vested rights.³⁵ In fact, courts have held that Area of Origin statutes do not apply to water that was properly diverted (i.e., in an earlier season) and stored for later use.³⁶

Along similar lines, the Watershed Protection Act as applied to the Delta provides that the State cannot deprive in-Delta users "of the prior right to all of the water reasonably required to adequately supply the beneficial needs of the watershed area, . . . ," and applies similar rules to the federal government.³⁷ Separately, the Delta Protection Act prioritizes the use of Delta water to control salinity, as does federal law.³⁸ The statute obligates the State to provide "reasonable protection" to beneficial uses, but does not specify that Delta farming, for instance, must be protected.³⁹

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This year, the State's...