Sustainable Use of Water in the Lower Colorado River Basin

Pacific Institute | November 26th, 1996

The Colorado River supplies water to nearly 30 million people and irrigates more than 1.5 million hectares of farmland in the United States and Mexico. But the diversion

The Colorado River supplies water to nearly 30 million people and irrigates more than 1.5 million hectares of farmland in the United States and Mexico. But the diversion of a huge amount of river water is seriously harming the delicate web of life that used to exist in the delta. The Sustainable Use of Water in the Lower Colorado River Basin, written by Sandra Postel of the Global Water Policy Project and Peter Gleick and Jason Morrison of the Pacific Institute, aims to clarify key concepts and criteria for sustainable water use within the Colorado basin, and then, using those criteria, present patterns of water management that can support economic prosperity and the environment. We do not presume to offer a single or best solution to water problems in the lower Colorado basin. The report’s goal is to define — both quantitatively and qualitatively — the unsustainable nature of current patterns of water use, and to demonstrate how technologies, policy actions, and management strategies can be combined to achieve more sustainable water use.

Sustainable wastewater reuse for agriculture

Nature Portfolio (Springer Nature) | June 6th, 2024

Sustainable Water and Environmental Management in the California Bay-Delta

National Academy of Sciences (NAS) | March 29th, 2012

Water management in the California Bay Delta is directed toward providing a more reliable water supply for California, and protecting and rehabilitating the Delta eco

Water management in the California Bay Delta is directed toward providing a more reliable water supply for California, and protecting and rehabilitating the Delta ecosystem, including five endangered and threatened populations and species of fish that live in or migrate through the Delta. However, water management in the Bay and Delta is distributed among many agencies and organizations, a structure that hinders the development and implementation of an integrated, comprehensive plan. As a result, recent Bay Delta planning efforts have not resolved the best plan for the environment or for satisfying anticipated water needs. Challenges include the fact that water scarcity has not been adequately addressed in planning for Delta water and environmental management; the interacting effects of the many environmental stressors that impact the Delta ecosystem, and the many biological and physical effects of climate change. This report discusses the issue of scarcity, factors affecting the listed species and the Delta ecosystem in general, future water-supply and delivery options, scientific uncertainties, the degree of restoration likely to be attainable, and the need for comprehensive planning. Key Messages Planning efforts to implement the two goals of providing a more reliable water supply for California and protecting and rehabilitating the Delta ecosystem have not led to clarity on how the inevitable tradeoffs between the two goals should be managed, particularly when water is in short supply. Climate change is one of most challenging and important issues confronting the management and rehabilitation of the Delta ecosystem. Changes in climate are expected to have profound effects on the physical and ecological structure and functioning of the Delta, as well as on the availability of water in California. Many environmental stressors, including water diversions, contaminants in the water, and introduced species affect the structure and functioning of Delta ecosystems. Interactions among stressors and between stressors and ecosystem processes are widespread and complex. Furthermore, species differ in their responses to stress. This complicates the interpretation and evaluation of the effects of stressors on the ecosystem, and makes it impossible to identify which stressor is the root cause of a certain environmental problem, or even to rank the stressors with any certainty. The large number of stressors, their effects and interactions lead to the conclusion that efforts to eliminate any one stressor are unlikely to reverse declines in listed species. Opportunities exist to mitigate or reverse the effects of many stressors. Continued effects analyses, modeling, and monitoring are necessary to ensure actions taken to rehabilitate the ecosystem are cost-effective. Due to the extensive physical changes that have already taken place and are still occurring in the Delta ecosystem and its tributary watersheds, it will not be possible to restore the habitat to its pre-disturbance state. Delta restoration programs will need to balance consideration of an ecosystem approach with the Endangered Species Act's emphasis on individual species. Assessments suggest that many species will be affected by shifts changes in the pattern and type of precipitation due to climate change. Projected increases in mean sea level and extremes of precipitation have the potential to increase the frequency of levee failures and the inundation of islands, in part because the levees continue to subside due to the oxidation of peat. Sea level rise also has the potential to enhance salt water intrusion and alter water quality. Planning and evaluation of future environmental and economic scenarios will need to address uncertainties in projections, integrated analysis, and the development of risk management strategies. Future planning should also include a climate-change based risk model and analysis that incorporates data on the actual changes in Delta conditions as well as alternative future climate change scenarios and their probability. The instability of levees and the fact that the failure of one levee can affect others are likely to be major issues for achieving any measure of water-supply reliability or ecosystem rehabilitation. Continuing the status quo of improving levees will not always be the most environmentally sustainable or economically defensible response in the years ahead. Science is necessary to inform actions and proposals, but does not provide the entire, prioritized, integrated analysis needed. Societal and political considerations are also important factors in determining the most appropriate policy. Undertaking a comprehensive review of water planning and management functioning would allow California to anticipate future needs such as water scarcity, balanced consideration of all statewide water use practices, and water engineering alternatives. As a result, the Delta would be an effective partner in statewide water management plans. It is likely that the scarcity of water for all needs in the Delta will become severe. While more effective planning is developed, the state will need to use its water resources efficiently and productively. The committee has not analyzed the benefits and disadvantages of an isolated conveyance facility, because not enough specific information was available about it, and therefore there is no recommendation with respect to its adoption as a major part of water management in the Delta. However, the considerations such as the form such a facility would take, its size, location, and the diversion design and operation, including the role of current diversions, should be analyzed as part of any integrated Delta plan, and compared to alternative water management options, including current operations.

Sustainable Water Management Strategy for Specialty Crop Expansion in the Sacramento Valley

Sacramento Area Council of Governments (SACOG) | June 26th, 2018

The Sacramento Area Council of Governments (SACOG) is an association of local governments in the six-county Sacramento Region of El Dorado, Placer, Sacramento, Sutter, Yo

The Sacramento Area Council of Governments (SACOG) is an association of local governments in the six-county Sacramento Region of El Dorado, Placer, Sacramento, Sutter, Yolo, and Yuba counties (excluding the Tahoe Basin in Placer and El Dorado counties) and the 22 cities therein. SACOG provides planning and funding for the region and serves as a forum for the study and resolution of regional issues. SACOG prepares the region’s long range plan which considers both transportation and land use. Through the lens of rural planning, SACOG has actively engaged in a Rural-Urban Connections Strategy (RUCS) Program that has studied ways to enhance rural economies and natural assets. The RUCS Program includes a scenario analysis modeling tool that links a parcel-level crop map with environmental and economic factors, including a comprehensive profile of per acre operational cost and return metrics for each crop. The study described in this report looks at how new agricultural crops and markets coupled with improved irrigation techniques will support new specialty crop acreage in the SACOG area. While new and improved irrigation techniques can result in better crop yields and decreased water demands, increases in irrigation efficiency also result in reduced groundwater recharge from irrigation return flows. SACOG received grant funding from the California Department of Food and Agriculture (CDFA) to evaluate the feasibility of recharging groundwater on agricultural lands within the SACOG portion of the Sacramento Valley to benefit specialty crop production. The primary goal of the project is to bring together a broad range of different factors impacting groundwater recharge and infiltration and to identify areas across the region that are most suited for strategic flooding of specialty crop fields; in other words, areas that will most efficiently and effectively facilitate recharge, while minimizing cost to the specialty crop producer. Ultimately, this feasibility information will be incorporated into SACOG’s RUCS model to evaluate the potential benefits of recharging groundwater on agricultural land for the benefit of specialty crops.

Sustained groundwater loss in California's Central Valley exacerbated by intense drought periods

American Geophysical Union (AGU) | July 4th, 2018

The accelerated rate of decline in groundwater levels across California’s Central Valley resultsfrom overdrafting and low rates of natural recharge and is exacerbated b

The accelerated rate of decline in groundwater levels across California’s Central Valley resultsfrom overdrafting and low rates of natural recharge and is exacerbated by droughts. The lack of observations with an adequate spatiotemporal resolution to constrain the evolution of groundwater resources poses severe challenges to water management efforts. Here we present SAR interferometric measurements of high-resolution vertical land motion across the valley, revealing multiscale patterns of aquifer hydrogeological properties and groundwater storage change. Investigating the depletion and degradation of the aquifer-system during 2007–2010, when the entire valley experienced a severe drought, we find that ~2% of total aquifer-system storage was permanently lost, owing to irreversible compaction of the system. Over this period, the seasonal groundwater storage change amplitude of10.11 ± 2.5 km3modulates a long-term groundwater storage decline of 21.32 ± 7.2 km3. Estimates for subbasins show more complex patterns, most likely associated with local hydrogeology, recharge, demand, and underground flow. Presented measurements of aquifer-system compaction provide a more complete understanding of groundwater dynamics and can potentially be used to improve water security.

Sustaining California Agriculture in an Uncertain Future

Pacific Institute | July 22nd, 2009

The report Sustaining California Agriculture in an Uncertain Future shows that California agriculture can flourish despite diminishing water supply and future uncertainty

The report Sustaining California Agriculture in an Uncertain Future shows that California agriculture can flourish despite diminishing water supply and future uncertainty from climate change, but it will require great strides in increasing the water efficiency of the agricultural sector. Many farmers and irrigation districts have already been making water-use efficiency improvements. Yet the analysis estimates that potential water savings of 4.5 – 6 million acre-feet each year can be achieved by expanding the use of efficient irrigation technologies and management practices.

Sutter Bypass East Levee Project Initial Study/Proposed Mitigated Negative Declaration

California Department of Water Resources (DWR) | July 10th, 2025

Sutter County Groundwater Management Plan

Sutter County | March 19th, 2012

Sutter County intends this GMP to be relevant for the entire County. Sutter County overlies the south central part of the Sacramento Valley Groundwater Basin, and specif

Sutter County intends this GMP to be relevant for the entire County. Sutter County overlies the south central part of the Sacramento Valley Groundwater Basin, and specifically the Sutter Subbasin and portions of the East Butte and North American Subbasins. The majority of the County is serviced by water and irrigation districts, reclamation districts, cities, and public utility districts, which have the authority to manage groundwater in their service areas. Unless those entities decline to manage groundwater on their own, and instead enter into agreements with the County, this GMP does not formally apply to those areas. If those entities choose not to adopt their own GMPs, they have the option of taking formal action to adopt the Sutter County GMP for their areas. By doing so, they will fulfill the requirements of the groundwater management provisions of the California Water Code.

Sutter Subbasin Groundwater Sustainability Plan

Sutter County | January 28th, 2022

With a 20-year implementation period and a 50-year planning horizon, the Sutter Subbasin GSP is considered to be a “living” document. The Sutter Subbasin Groundwater

With a 20-year implementation period and a 50-year planning horizon, the Sutter Subbasin GSP is considered to be a “living” document. The Sutter Subbasin Groundwater Sustainability Agencies (GSAs) will implement this GSP using adaptive management strategies to respond to challenges related to groundwater sustainability, including monitoring of conditions in the Subbasin according to a prescribed schedule and implementing projects and management actions (PMAs). Conditions will be evaluated on an annual basis (or more frequently, as warranted) utilizing monitoring data collected as part of this GSP, as well as other publicly available sources, and PMAs will be added or revised in the GSP annual reports. During five-year GSP evaluations, the GSP will also be reviewed and revised, as needed, as more is known about the effects of current and future conditions. Due to size, this file has been divided into three parts. Part 1, Part 2, Part 3

Sycamore Alluvial Woodland Habitat Mapping and Regeneration Study

San Francisco Estuary Institute (SFEI) | February 1st, 2017

This study investigates the relative distribution, health, and regeneration patterns of two major stands of sycamore alluvial woodland (SAW), representing managed and nat

This study investigates the relative distribution, health, and regeneration patterns of two major stands of sycamore alluvial woodland (SAW), representing managed and natural settings. Using an array of ecological and geomorphic field analyses, we discuss site characteristics favorable to SAW health and regeneration, make recommendations for restoration and management, and identify next steps. Findings from this study will contribute to the acquisition, restoration, and improved management of SAW as part of the Santa Clara Valley Habitat Plan (VHP).