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A Salton Sea Chronology (Prehistory-2015)

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A Salton Sea Chronology (Prehistory-2015)
U.S. Bureau of Reclamation (USBR) | January 14, 2016...
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Application of synthetic scenarios to address water resource concerns: A management-guided case study from the Upper Colorado River Basin

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Application of synthetic scenarios to address water resource concerns: A management-guided case study from the Upper Colorado River Basin
Climate Services, Elsevier B.V. | December 9, 2017...
Summary
Water managers are increasingly interested in better understanding and planning for projected resource impacts from climate change. In this management-guided study, we use a...
Water managers are increasingly interested in better understanding and planning for projected resource impacts from climate change. In this management-guided study, we use a very large suite of synthetic climate scenarios in a statistical modeling framework to simultaneously evaluate how (1) average temperature and precipitation changes, (2) initial basin conditions, and (3) temporal characteristics of the input climate data influence water year flow in the Upper Colorado River. The results here suggest that existing studies may underestimate the degree of uncertainty in future streamflow, particularly under moderate temperature and precipitation changes. However, we also find that the relative severity of future flow projections within a given climate scenario can be estimated with simple metrics that characterize the input climate data and basin conditions. These results suggest that simple testing, like the analyses presented in this paper, may be helpful in understanding differences between existing studies or in identifying specific conditions for physically based mechanistic modeling. Both options could reduce overall cost and improve the efficiency of conducting climate change impacts studies.

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Basis of Design Report – Species Conservation Habitat

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Basis of Design Report – Species Conservation Habitat
California Department of Water Resources (DWR) | April 14, 2014...
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The Species Conservation Habitat (SCH) project provides shallow water habitat to support fish and wildlife dependent upon the Salton Sea that is being...

The Species Conservation Habitat (SCH) project provides shallow water habitat to support fish and wildlife dependent upon the Salton Sea that is being lost due to salinity increases and the declining water surface elevation. The Project is located at the southern end of the Salton Sea (Sea) in Imperial County, California. Through the environmental review process, a Preferred Alternative was selected that encompasses 3,770 acres on both sides of the New River. The Project would include water supplies, berms to contain the water, and various other support facilities.

The early start construction of the project is to develop habitat consistent with the EIS/EIR preferred alternative that is scaled down to fit the level of implementation funding currently available. The design described in this report is for early start project (Project) of the SCH and is limited to the 640 acres located within the bay on the east side of the New River. This report provides a summary of the primary design features and considerations associated with the habitat development. A more detailed discussion of the background, purpose, goals, design elements, Preferred Alternative, and Project impacts can be found in the 2011 draft EIS/EIR.

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Colorado River Basin Environmental Transfers Scorecard

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Colorado River Basin Environmental Transfers Scorecard
Stanford Woods Institute for the Environment and the Bill Lane Center for the American West | March 16, 2017...
Summary
The Colorado River and its tributaries support more than 35 million people and irrigate more than four million acres of farmland. At the...
The Colorado River and its tributaries support more than 35 million people and irrigate more than four million acres of farmland. At the same time, the river supports 30 fish species found nowhere else on earth and inspires millions of visitors and residents alike with its sheer beauty. However, growing water scarcity caused by increased water use, hydrologic variability and climate change loom over all the Colorado River provides.

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Environmental Water Transactions in the Colorado River Basin: A Closer Look

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Environmental Water Transactions in the Colorado River Basin: A Closer Look
Stanford Woods Institute for the Environment and the Bill Lane Center for the American West | November 14, 2018...
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Over the last 30 years, the voluntary transfer of water and water rights for environmental uses has become a recognized strategy for restoring streamflow...
Over the last 30 years, the voluntary transfer of water and water rights for environmental uses has become a recognized strategy for restoring streamflow in the Western United States. Historically, taking water out of a stream was a legally required element of an appropriative water right. Water rights holders who left all or a portion of their right instream to enhance fish populations, riparian habitat or recreation, risked forfeiture or diminishment of their water right. Beginning in the 1980’s, state laws began to recognize both the appropriation of new water rights for instream use and to allow the transfer and amendment of existing appropriative rights for those uses.

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Fill Mead First: a technical assessment

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Fill Mead First: a technical assessment
Utah State University | November 10, 2019...
Summary
The Fill Mead First (FMF) plan would establish Lake Mead reservoir as the primary water storage facility of the main-stem Colorado River and would...

The Fill Mead First (FMF) plan would establish Lake Mead reservoir as the primary water storage facility of the main-stem Colorado River and would relegate Lake Powell reservoir to a secondary water storage facility to be used only when Lake Mead is full. The objectives of the FMF plan are to re-expose some of Glen Canyon’s sandstone walls that are now inundated, begin the process of re-creating a riverine ecosystem in Glen Canyon, restore a more natural stream-flow, temperature, and sediment-supply regime of the Colorado River in the Grand Canyon ecosystem, and reduce system-wide water losses caused by evaporation and movement of reservoir water into ground-water storage. The FMF plan would be implemented in three phases. Phase I would involve lowering Lake Powell to the minimum elevation at which hydroelectricity can still be produced (called minimum power pool elevation): 3490 ft asl (feet above sea level). At this elevation, the water surface area of Lake Powell is approximately 77 mi2, which is 31% of the surface area when the reservoir is full. Phase II of the FMF plan would involve lowering Lake Powell to dead pool elevation (3370 ft asl), abandoning hydroelectricity generation, and releasing water only through the river outlets. The water surface area of Lake Powell at dead pool is approximately 32 mi2 and is 13% of the reservoir surface area when it is full. Implementation of Phase III would necessitate drilling new diversion tunnels around Glen Canyon Dam in order to eliminate all water storage at Lake Powell. In this paper, we summarize the FMF plan and identify critical details about the plan’s implementation that are presently unknown. We estimate changes in evaporation losses and ground-water storage that would occur if the FMF plan was implemented, based on review of existing data and published reports. We also discuss significant river-ecosystem issues that would arise if the plan was implemented.

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From Desert Wasteland to Agricultural Wonderland: The Story of Water and Power

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From Desert Wasteland to Agricultural Wonderland: The Story of Water and Power
Imperial Irrigation District (IID) | October 3, 1977...
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Future dryness in the southwest US and the hydrology of the early 21st century drought

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Future dryness in the southwest US and the hydrology of the early 21st century drought
Proceedings of the National Academy of Sciences (PNAS) | December 14, 2010...
Summary
Recently the Southwest has experienced a spate of dryness, which presents a challenge to the sustainability of current water use by human and...

Recently the Southwest has experienced a spate of dryness, which presents a challenge to the sustainability of current water use by human and natural systems in the region. In the Colorado River Basin, the early 21st century drought has been the most extreme in over a century of Colorado River flows, and might occur in any given century with probability of only 60%. However, hydrological model runs from downscaled Intergovernmental Panel on Climate Change Fourth Assessment climate change simulations suggest that the region is likely to become drier and experience more severe droughts than this. In the latter half of the 21st century the models produced considerably greater drought activity, parti- cularly in the Colorado River Basin, as judged from soil moisture anomalies and other hydrological measures. As in the historical record, most of the simulated extreme droughts build up and per- sist over many years. Durations of depleted soil moisture over the historical record ranged from 4 to 10 years, but in the 21st century simulations, some of the dry events persisted for 12 years or more. Summers during the observed early 21st century drought were re- markably warm, a feature also evident in many simulated droughts of the 21st century. These severe future droughts are aggravated by enhanced, globally warmed temperatures that reduce spring snowpack and late spring and summer soil moisture. As the climate continues to warm and soil moisture deficits accumulate beyond historical levels, the model simulations suggest that sustaining water supplies in parts of the Southwest will be a challenge.

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Hazard: The Future of the Salton Sea With No Restoration Project

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Hazard: The Future of the Salton Sea With No Restoration Project
Pacific Institute | May 1, 2006...
Summary
The Salton Sea lies on the brink of catastrophic change. The amount of water flowing into the Sea in the next twenty years...
The Salton Sea lies on the brink of catastrophic change. The amount of water flowing into the Sea in the next twenty years will decrease by more than 40%, causing its surface elevation to drop by more than 20 feet, rapidly shrinking its volume by more than 60%, tripling its salinity, and exposing more than 100 square miles of dusty lakebed to the desert’s blowing winds. These changes will cause four major impacts:

Human health in the Imperial and Coachella valleys – currently home to more than 400,000 people and growing quickly – will be harmed by the estimated 33% increase in the amount of fine windblown dust in the basin. The Imperial Valley already suffers from the highest childhood asthma hospitalization rate in the state; the growing number of retirees living in both valleys are especially susceptible to poor air quality.

Air quality in these two valleys – which already fails to meet state and federal air quality standards – would get much worse, increasing the cost of bringing these areas into compliance.

Air quality-related litigation and state liability will increase. California has assumed ultimate responsibility for managing only those lands exposed due to a recent set of water transfers, constituting about half of the estimated 134 square miles exposed in 30 years. Responsibility for managing any dust blowing off the other 60 or so square miles will rest with the individual property owner. However, there is no clear way to determine which lands will be exposed due to the water transfers and which will be exposed due to other actions. Total air quality management costs at Owens Lake have exceeded $400 million. Costs at the Salton Sea could be higher.

Many – if not most – of the hundreds of thousands of birds that currently use the Sea will lose their roosting and breeding habitats and their sources of food. The Sea’s fish will be almost entirely gone within a dozen years. Those birds that remain will suffer from disease and the reproductive deformities and failures that plagued the Kesterson National Wildlife Refuge twenty years ago. Some of the endangered and threatened species that use the Sea may be able to find other habitats, but others could suffer significant population losses.

The tremendous scale of the Sea adds to its complexity, and the difficulty of finding a viable solution. The Sea currently runs almost 35 miles long, and 15 miles at its widest point, covering about 365 square miles. It has the largest surface area of any lake in California, yet is barely 50 feet at its deepest point. The Sea is 1/3 saltier than the ocean, and, fed by the fertilizers running off of neighboring fields, sustains incredible levels of biological productivity. Until recently, the amount of water entering the Sea was roughly balanced by the amount of water evaporating from its broad surface. Stabilizing the Sea at its current salinity would require the removal of more than four million tons of salt each year, assuming flows to the Sea do not change.

But they will change. Under a set of agreements signed in 2003, the Imperial Valley has begun to transfer water to San Diego County, ultimately reducing flows to the Salton Sea. Other actions, including actions in Mexico, will also reduce the amount of water flowing to the Sea, by 45% or more in the next 30-40 years. These changes will dramatically decrease the size of the Salton Sea and the quality of its water.

In September, 2003, the California legislature passed a set of laws that implement the 2003 water agreements and provide a 15-year reprieve for the Sea. The legislation offers the prospect of more than $300 million of restoration funds, but it does not guarantee a long-term restoration project for the Salton Sea. California’s Resources Agency will submit a Salton Sea Ecosystem Restoration Plan and related documents to the state legislature by December 31, 2006. The cost of any long-term restoration plan will almost certainly exceed a billion dollars. Although various private-public partnerships have been suggested, funding and implementation of any restoration plan is far from certain, especially given the lack of consensus on a preferred alternative.
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Missing Water: The Uses and Flows of Water in the Colorado River Delta Region
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Missing Water: The Uses and Flows of Water in the Colorado River Delta Region
Pacific Institute | September 1, 2001...
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The Pacific Institute for Studies in Development, Environment, and Security is pleased to announce the release of Missing Water: The Uses and Flows of...
The Pacific Institute for Studies in Development, Environment, and Security is pleased to announce the release of Missing Water: The Uses and Flows of Water in the Colorado River Delta Region. This new study describes the fate of the millions of acre-feet of water diverted from the Colorado River at and below Imperial Dam, and the total inflows to and outflows from the Colorado River delta region more generally.

This study uses the classic hydrologic boundaries of the delta region described by Godfrey Sykes in 1937, encompassing some 3,325 square miles (8,611 square kilometers) in the states of Arizona, Baja California, California, and Sonora, including the Imperial, Mexicali, and San Luis valleys, Yuma Project lands, and the lower Coachella Valley. The study period examines the flows and uses of water in the years 1991-1998, divided into Flood and Non-Flood years to reflect the tremendous variability of mainstem Colorado River flows.

Missing Water compiles flow data along the mainstem and along diversions within the delta region, the first time such data has been compiled for the region as a whole. The study also report consumptive uses of water in the agricultural and urban sectors, and estimates such use by the environment. Agricultural use is also reported for the major crops in the region, both by acreage and by water use.

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