Tulare Lake

Adaptability and adaptations of California’s water supply system to dry climate warming

Climactic Change (Springer) | November 27th, 2007

Economically optimal operational changes and adaptations for California’s water supply system are examined for a dry form of climate warming (GFDL CM2.1 A2) with year 2

Economically optimal operational changes and adaptations for California’s water supply system are examined for a dry form of climate warming (GFDL CM2.1 A2) with year 2050 water demands and land use. Economically adaptive water management for this climate scenario is compared to a similar scenario with the historical climate. The effects of population growth and land use alone are developed for comparison. Compared with the historic hydrology, optimized operations for the dry climate warming scenario raise water scarcity and total operation costs by $490 million/year with year 2050 demands. Actual costs might be somewhat higher where non-economic objectives prevail in water management. The paper examines the economical mix of adaptation, technologies, policies, and operational changes available to keep water supply impacts to such modest levels. Results from this screening model suggest promising alternatives and likely responses and impacts. Optimized operations of ground and surface water storage change significantly with climate. Dry-warm climate change increases the seasonal storage range of surface reservoirs and aquifers. Surface reservoir peak storage usually occurs about a month earlier under dry-warm climate change.

Addendum to the State Water Project and Central Valley Project Drought Contingency Plan

California Department of Water Resources (DWR) | July 29th, 2022

This Addendum includes current hydrologic conditions, plus updates on the following: operations status and the latest SWP and CVP (collectively referred to as Projects) o

This Addendum includes current hydrologic conditions, plus updates on the following: operations status and the latest SWP and CVP (collectively referred to as Projects) operations forecasts; species status; and known WY 2022 drought actions.

Addendum to the State Water Project and Central Valley Project Drought Contingency Plan

California Department of Water Resources (DWR) | August 31st, 2022

This Addendum includes current hydrologic conditions, plus updates on the following: operations status and the latest SWP and CVP (collectively referred to as Projects) o

This Addendum includes current hydrologic conditions, plus updates on the following: operations status and the latest SWP and CVP (collectively referred to as Projects) operations forecasts; species status; and known WY 2022 drought actions.

Addressing Nitrate in California’s Drinking Water Technical Report 1: Project and Technical Report Outline

University of California, Davis (UC Davis) | July 2nd, 2012

Addressing Nitrate in California’s Drinking Water Technical Report 2: Nitrogen Sources and Loading to Groundwater

University of California, Davis (UC Davis) | July 2nd, 2012

Nitrate loading to groundwater in the Tulare Lake Basin and Salinas Valley is widespread and chronic, and is overwhelmingly the result of crop and animal agricultural ac

Nitrate loading to groundwater in the Tulare Lake Basin and Salinas Valley is widespread and chronic, and is overwhelmingly the result of crop and animal agricultural activities. Urban wastewater, septic systems, and other sources may have significant localized impact. Due to long transit times, the impact on groundwater resources is a legacy for years and decades to come.

Addressing Nitrate in California’s Drinking Water Technical Report 3: Nitrogen Source Reduction to Protect Groundwater Quality

University of California, Davis (UC Davis) | July 2nd, 2012

Although reduction of anthropogenic loading of nitrate to groundwater aquifers will not reduce contamination in the short term (due to long travel times), reduction effo

Although reduction of anthropogenic loading of nitrate to groundwater aquifers will not reduce contamination in the short term (due to long travel times), reduction efforts are a critical component of any long term solution to the problem of high nitrate in drinking water. Technologies are available for reducing the transfer of nitrate to groundwater from surface sources. Such technologies involve (1) reducing the amount of nitrogen (N) discharged or applied to the land and (2) controlling the amount of water applied to land which serves as the carrier of nitrate. Many of these source control methods require changes in land management and upgrading of infrastructure.

Addressing Nitrate in California’s Drinking Water Technical Report 4: Groundwater Nitrate Occurrence

University of California, Davis (UC Davis) | July 2nd, 2012

This report reviews the hydrogeology and groundwater quality in the Tulare Lake Basin (TLB) and Salinas Valley (SV). We also assembled groundwater quality data from near

This report reviews the hydrogeology and groundwater quality in the Tulare Lake Basin (TLB) and Salinas Valley (SV). We also assembled groundwater quality data from nearly two dozen local, state, and federal agencies and other sources into a dataset, here referred to as the (Central) California Ambient Spatio-Temporal Information on Nitrate in Groundwater (CASTING) dataset. The dataset combines nitrate concentrations from 16,709 individual samples taken at 1,890 wells in the Salinas Valley (SV) and from 83,375 individual samples taken at 17,205 wells in the Tulare Lake Basin (TLB) collected from the 1940s to 2011, accounting for a total of 100,084 samples from 19,095 wells. Almost 70% of these samples were collected from 2000 to 2010; only 15% of the samples were collected prior to 1990. Half of all wells sampled had no recorded samples prior to 2000.

Addressing Nitrate in California’s Drinking Water Technical Report 5

University of California, Davis (UC Davis) | July 31st, 2012

This report explores methods and costs of remediation of groundwater nitrate contamination in the Tulare Lake Basin and Salinas Valley. Groundwater cleanup, or remediati

This report explores methods and costs of remediation of groundwater nitrate contamination in the Tulare Lake Basin and Salinas Valley. Groundwater cleanup, or remediation, is one of the most difficult actions in the environmental sciences, even when done on the scale of a small contaminant plume (1000s of cubic meters). Remediation of entire groundwater basins has never been attempted at the scale and depths of the Salinas Valley and Tulare Lake Basin, on the order of billions of cubic meters. This analysis shows that direct remediation to remove nitrate from large groundwater basins is extremely costly and not technically feasible. In situ remediation, though technologically infeasible as a regional remedy, is appropriate in certain areas of shallow groundwater with high contaminant levels. Traditional pump and treat (ex situ) methods are too slow to produce results on the regional scale in an acceptable time frame, prohibitively expensive, and impractical to implement. A novel form of pump-and-treat remediation is possible in the study area, but not yet widely practiced. By monitoring the nitrogen content of pumped irrigation water, and taking that ambient nutrient source into account when calculating additive fertilizer amounts, farmers can reduce the amount of nitrogen input to the aquifer. Such an approach is not unlike phytoremediation and is herein called “pump-and fertilize.” Pump-and-fertilize is part of an effective nutrient management program. Due to the nature of irrigation with groundwater, it is as much a source reduction method as it is a form of groundwater remediation. Hot spot and pump-and-fertilize remediation alone will not solve the problem of groundwater nitrate contamination. A new approach is needed that combines regional groundwater and nitrogen management strategies. This approach would include monitoring, source reduction, maximization of clean groundwater recharge across agricultural landscapes, pump-and-fertilize, and in situ treatment targeted at shallow, high-concentration plumes to place regional water quality on a trajectory toward improvement. Modeling and monitoring of regional groundwater quality are integral to an effective long-term management strategy.

Addressing Nitrate in California’s Drinking Water Technical Report 6: Drinking Water Treatment for Nitrate

University of California, Davis (UC Davis) | July 2nd, 2012

The purpose of the first three sections of this document is to provide a detailed guide to the current state of nitrate treatment alternatives that can be used as a refe

The purpose of the first three sections of this document is to provide a detailed guide to the current state of nitrate treatment alternatives that can be used as a reference tool for the drinking water community. The remainder of this document focuses on nitrate treatment of drinking water in California and specifically in the Tulare Lake Basin and the Salinas Valley.

Addressing Nitrate in California’s Drinking Water Technical Report 7: Alternative Water Supply Options for Nitrate Contamination

University of California, Davis (UC Davis) | July 2nd, 2012

The Tulare Lake Basin and Salinas Valley were chosen as pilot study areas because communities in these regions are faced with the need to manage high nitrate loads from

The Tulare Lake Basin and Salinas Valley were chosen as pilot study areas because communities in these regions are faced with the need to manage high nitrate loads from agricultural lands and dairies, have a high risk of exposure to nitrate contamination in groundwater, and often cannot afford treatment or alternative water supply options. These factors combine to make the Tulare Lake Basin and Salinas Valley highly susceptible to health effects from nitrate in drinking water. There are 371 active community public water systems (CPWS) and 30 state small water systems (SSWS) in the study area (281 and 120 in the Tulare Lake Basin and Salinas Valley, respectively). These systems supply water to about 2.4 million people. An estimated additional 245,490 people in these regions get their drinking water from an estimated 74,400 private domestic wells (self-supplied households or local small water systems with fewer than five connections) that are unregulated and largely unmonitored.