Socio‐ecohydrology and the urban water challenge

Ecohydrology (Wiley) | March 11th, 2011

Urban water systems are highly engineered. However, hydrology and ecology are still closely linked in semi‐arid urban ecosystems in which surface characteristics, veget

Urban water systems are highly engineered. However, hydrology and ecology are still closely linked in semi‐arid urban ecosystems in which surface characteristics, vegetation, and water flows are all highly transformed. Although these systems are human‐dominated, there are many uncertainties in the water budgets of semi‐arid cities, because evapotranspiration, runoff, groundwater recharge, and leakage are poorly constrained. Decision‐making, governance, and socioeconomic factors play important roles in determining urban hydrologic budgets. We offer a framework to integrate these factors in studies that combine biophysical and social dimensions of the urban water system using the example of western US cities, which are facing critical issues in water supply and demand, and which can benefit from a more comprehensive understanding of the factors that determine water consumption, distribution and availability. Because of the severity of the water crisis in the western US, and the biophysical, institutional, and cultural barriers to developing and implementing new water management practices, this region provides useful lessons for addressing water challenges in other regions.

Solano Subbasin Groundwater Sustainability Plan

Solano Subbasin GSA Collaborative | November 30th, 2021

The Sustainable Groundwater Management Act (SGMA) encourages groundwater management at the local level. Local entities are responsible for forming Groundwater Sustainabil

The Sustainable Groundwater Management Act (SGMA) encourages groundwater management at the local level. Local entities are responsible for forming Groundwater Sustainability Agencies (GSAs) to develop and implement Groundwater Sustainability Plans (GSPs) to guide sustainable management of groundwater basins or subbasins identified as high or medium priority by the State. Five GSAs in the Solano Subbasin organized to form the Solano Collaborative to develop a single GSP for the Subbasin: Solano Subbasin GSA, Solano Irrigation District GSA, City of Vacaville GSA, Northern Delta GSA, and Sacramento County GSA. The Solano Collaborative together with five other GSAs have adopted the Solano Subbasin Groundwater Sustainability Plan.

Solar Energy and Groundwater in the San Joaquin Valley

Public Policy Institute of California (PPIC) | October 26th, 2022

The Sustainable Groundwater Management Act (SGMA) requires groundwater users to bring their basins into balance over the next two decades. In the San Joaquin Valley, this

The Sustainable Groundwater Management Act (SGMA) requires groundwater users to bring their basins into balance over the next two decades. In the San Joaquin Valley, this will likely mean taking more than 500,000 acres of agricultural land out of intensive irrigated production. Local and regional economies could be stressed as a result, with some regular employment opportunities in agriculture disappearing and public revenues declining if lands are not put to new uses. As landowners and newly formed groundwater agencies tackle the groundwater deficits in their areas, utility-scale solar development—already an attractive option for landowners owning property with or without water rights—could offer an opportunity to keep lands that exit irrigated production economically productive. Moreover, development could provide multiple benefits by helping to supplement habitat and mitigate dust generation on transitioning lands. However, the expansion of solar hinges on whether state-level energy system planning processes—in conjunction with local land use planning—can address the transmission challenges that threaten the region’s promise as a solar power hub.

Sonoma Valley Groundwater Sustainability Plan

Sonoma Water | January 29th, 2022

South American Subbasin Groundwater Sustainability Plan

Sacramento County | October 29th, 2021

Groundwater management in the South American Subbasin (SASb) has been occurring for decades. Stable groundwater conditions in terms of groundwater levels, storage volume

Groundwater management in the South American Subbasin (SASb) has been occurring for decades. Stable groundwater conditions in terms of groundwater levels, storage volume, and interconnected surface waters have been achieved due to a variety of historically implemented projects and management actions. To ensure continued sustainable conditions allowing for future groundwater use to the benefit of all users in the SASb over the next 50-years, with climate change considered, a groundwater sustainability plan (GSP) has been developed and will be implemented to achieve the sustainability goal for the basin in the next 20 years. Due to size, this file has been divided into eight parts. Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8

South Coast Hydrologic Region Groundwater Update

California Department of Water Resources (DWR) | April 1st, 2015

The primary goal of the South Coast Hydrologic Region (South Coast region) groundwater update is to expand information about region-specific groundwater conditions for Ca

The primary goal of the South Coast Hydrologic Region (South Coast region) groundwater update is to expand information about region-specific groundwater conditions for California Water Plan Update 2013 and to guide more informed groundwater management actions and policies. A second goal is to steadily improve the quality of groundwater information in future California Water Plan (CWP) updates to a level that will enable regional water management groups (RWMGs) to accurately evaluate their groundwater resources and implement management strategies that can meet local and regional water resource objectives within the context of broader statewide objectives. The final goal is to identify data gaps and groundwater management challenges that will guide prioritizing of future data collection and funding opportunities relevant to the region. This regional groundwater update is not intended to provide a comprehensive and detailed examination of local groundwater conditions, or be a substitute for local studies and analysis. Nonetheless, where information is readily available, this update does report some aspects of the regional groundwater conditions in greater detail.

South Kings Groundwater Sustainability Agency Groundwater Sustainability Plan

South Kings Groundwater Sustainability Agency | December 19th, 2019

South Kings Groundwater Sustainability Agency Groundwater Sustainability Plan (Revised)

South Kings Groundwater Sustainability Agency | July 13th, 2022

South of Kern River Groundwater Sustainability Plan (GSP) for Certain Lands Overlying the Kern County Subbasin

South of the Kern River Groundwater Sustainability Agencies (SoKR GSAs) | July 27th, 2022

Southeast California Regional Basin Study

U.S. Bureau of Reclamation (USBR) | September 1st, 2015

The United States Department of the Interior’s WaterSMART (Sustain and Manage America’s Resources for Tomorrow) Basin Study Program is a 21st Century approach to help

The United States Department of the Interior’s WaterSMART (Sustain and Manage America’s Resources for Tomorrow) Basin Study Program is a 21st Century approach to help address water supply challenges. The Southeast California Regional Basin Study (Study) takes a collaborative approach to solve local water supply and regional conveyance and storage issues. As part of this Study, the Bureau of Reclamation’s Southern California Area Office cooperated with the Borrego Water District (BWD), Coachella Valley Water District (CVWD), Imperial Irrigation District (IID) and other interested regional stakeholders to assess water supply and demand challenges in the Southeast California region. This Study’s report is comprised of seven chapters; they are: introduction, supply, demand, alternative strategies, alternative analysis, findings, and references. Three appendices provide additional details regarding climate change modeling results, engineering design and economic analysis. The Study focuses on a regional area encompassing the Coachella, Borrego and Imperial Valleys. The Study addresses current and future supply and demand imbalances, provides an assessment of existing infrastructure resources, and develops options and alternatives to solve identified issues and help plan for an uncertain water supply future. The local stakeholders provided substantial informational resources on historical and projected supply and demand, and existing infrastructure. The water districts’ background information includes numerous groundwater, urban water and integrated regional planning studies, all of which were produced and/or updated between 2010 and 2012. Extensive supply and demand studies for the Colorado River Basin and California’s Central Valley – the two imported water supply sources for the Study area – also contributed data to this Study. Reclamation’s Colorado River Basin Water Supply and Demand Study (Colorado River Basin Study) (Reclamation, 2012) and the California Department of Water Resources biennial State Water Project (SWP) report (State of California, 2012 a and b) were both completed in 2012. Reclamation’s Colorado River Basin Study included several technical analyses related to optimal water utilization, conveyance and storage alternatives relative to climate change and future water supply uncertainty. Because the Southeast California Basin Study region is dependent on both Colorado River and SWP imports, several sections of the Study reference and/or summarize both reports extensively. Existing data was used to develop structural and non-structural options to resolve supply-demand imbalances and future uncertainty. Non-structural options included governance, and regulatory or operational changes that could facilitate stakeholder processes to better conserve water or improve the use of existing facilities to convey and store water. Non-structural options were addressed qualitatively due to the complexity of interagency negotiations that would likely be involved. The structural options involved an appraisal level design effort to evaluate pipeline alignments to convey water supplies between the Study stakeholders. Both the structural and non-structural options were assessed in their capability to resolve regional water supply and demand relative to future climate uncertainties. Climate change scenarios analyzed the potential impacts increasing temperatures and changes in precipitation may have on supply and demand across the Study area. The analysis addressed both local and imported supply sources. Climate change is expected to result in increasing temperatures across the Study area and in the Colorado River and SWP basins over time. As temperatures continue to increase, annual precipitation will become more variable. Precipitation changes may affect recharge of the Study area’s local groundwater aquifers and the Colorado River and SWP snowpacks. The climate effects on imported supply have been extensively discussed in the Colorado River Basin Study and the biennial SWP report. Increasing temperatures will increase both supply and demand uncertainty. CVWD could see an increase in SWP supply deliveries under average or greater precipitation-snowpack conditions. Dry years or extended droughts could substantially decrease SWP deliveries. However, CVWD and IID receive the majority of their supply from the Colorado River. Future climate scenarios indicate an increased potential for lower basin shortages. As senior water right holders and under the Secretary of the Interior’s Colorado River Interim Guidelines for Lower Basin Shortages and Coordinated Operations for Lake Powell and Lake Mead, IID and CVWD would not be impacted by short-term shortage issues. The Colorado River Basin Study analysis indicates these shortage vulnerabilities could be mitigated by up to 50% through a variety of management actions and operational changes. Each Study option was assessed as an adaptive strategy to climate change. The structural options to convey and store water in the Borrego Valley groundwater basin are not viable at the present time. A non-structural option may be more cost-effective for the Study region, have the potential to meet the Study objectives, and may offset climate change uncertainty that is impacting available imported water supplies. Further study effort could include fostering groundwater sustainability in the Borrego Valley and promoting opportunities for additional groundwater banking between IID and CVWD in the Coachella Valley, per an October 2003 agreement. Other water and related resource options generated from discussions during the course of this Study include increasing storage opportunities at Lake Henshaw Dam, implementing best practices for flood control basins, and brackish desalination. These options may all play a greater role in diversifying the region’s water supply in the future. However, additional study is required to assess these water resource options.