An Implementation Blueprint for Enhancing Groundwater Recharge in the San Fernando Basin

University of Southern California (USC) | December 31st, 2008

The purpose of this report is to analyze the potential of providing ground water recharge in the San Fernando Basin (SFB) using native water, including the identification

The purpose of this report is to analyze the potential of providing ground water recharge in the San Fernando Basin (SFB) using native water, including the identification of strategic plans for the recharge project.

An Index of Biotic Integrity (IBI) for Perennial Streams in California’s Central Valley

California State Water Resources Control Board (SWRCB) | December 1st, 2008

Bioassessment is the science of using aquatic organisms as indicators of ecological condition in streams in rivers. Many types of organisms can be used as indicat

Bioassessment is the science of using aquatic organisms as indicators of ecological condition in streams in rivers. Many types of organisms can be used as indicators, for example fish or algae, but bioassessment is most frequently based on benthic macroinvertebrates (BMIs), which are small but visible bottom-dwelling organisms such as insects. BMI data sets typically consist of long lists of species (or taxa) found in a sample and their relative abundances. These data can be simplified into measures of biological condition such as indices of biotic integrity (IBIs) that are designed to be sensitive to human-caused alterations to the landscape, to stream channels and riparian zones, and to water chemistry. IBIs function much like economic indicators: high IBI scores reflect good ecological conditions while low IBI scores reflect poor ecological conditions. Bioassessment is increasingly used throughout California by water quality monitoring programs, but in the Central Valley bioassessment is more challenging than in other regions of the state because the entire landscape and most streams are highly altered by human activities such as urbanization, agriculture and water diversions. This makes it impossible to evaluate how BMIs respond across a complete gradient of human disturbance within the region, that is, from minimally disturbed reference sites where human activity is absent or minimal and which therefore set the benchmark for biological expectations, to the most altered sites with degraded biology. In the Central Valley, minimally disturbed reference sites are no longer available. Even the ‘least-disturbed’ sites, which represent the best-available chemical, physical and biological habitat conditions given the current state of the landscape, are markedly disturbed. Reference sites in other parts of California, such as the Sierra Nevada or the Sierra foothills, may be significantly less disturbed than Central Valley reference sites. In this study, BMI data sets from 11 studies conducted at various intervals over the last 14 years were compiled to build an IBI for Central Valley streams. Data were not collected consistently by the different studies, and many gaps were present in associated physical habitat and water chemistry data sets. This could be corrected for BMI samples by standardizing to a consistent level of taxonomic effort. Gaps in other data could not be addressed. Criteria for defining ‘best-available’ reference sites were established as data allowed and were based on local urban and agricultural intensity, stream channel and riparian condition, and stream substrate composition. Eighty BMI metrics were evaluated for inclusion in the IBI based on 4 criteria: 1) sufficient range for scoring; 2) responsiveness to land use and/or local disturbance variables measured at the 150-meter sampling reach (as data allowed); 3) good discrimination between reference and test sites; 4) lack of correlation with other responsive metrics. Five final metrics were selected and scored for inclusion in the IBI: collector richness (number of taxa that are collector- feeders), predator richness (number of taxa that are predators), percent EPT taxa (percent of taxa that are mayflies, stoneflies, or caddisflies), percent clinger taxa (percent of taxa that cling to vegetation) and Shannon diversity (a composite measure of taxonomic richness and evenness of abundance). The final IBI showed good discrimination between reference and test sites, and was validated with an independent data set. BMI metrics and the final IBI were more strongly related to reach-scale physical habitat variables than to water chemistry or land use variables, but detailed water chemistry was lacking for many sites, and some studies have shown that response to land use diminishes when more than 10% of a watershed is degraded by human activities. Despite data gaps that were less than ideal for indicator development, this study is the first to set expectations for Central Valley BMI assemblages based on best-available reference sites. The Central Valley IBI can be used as a general interpretive framework for benthic samples collected from perennial streams on the valley floor and provides an objective means for rating biological condition in a region with high urban and agricultural intensity. The ability to rank sampling sites relative to explicitly defined biological expectations is essential to any biological monitoring program. Therefore, this index may prove useful in several monitoring applications, including California’s non- point source CMAP program where sampling was stratified to assess and compare stream condition in urban, agricultural and forested watersheds, in stormwater monitoring programs, in point-source pollution investigations, and in stream restoration monitoring. Key recommendations include: 1) that all future bioassessment projects in the Central Valley should collect quantitative physical habitat and water chemistry with consistent protocols at all sites; in situ chemistry and rapid (qualitative) physical habitat are not sufficient for screening reference sites or evaluating BMI responses to stressor gradients; 2) that bioassessment should be added to NPS monitoring where programs are already collecting more intensive stressor data such as pesticides, nutrients and metals. This will provide California’s monitoring programs with better datasets to support future analyses.

An Introduction to High-Frequency Nutrient and Biogeochemical Monitoring for the Sacramento– San Joaquin Delta, Northern California

U.S. Geological Survey (USGS) | July 11th, 2017

This report is the first in a series of three reports that provide information about high-frequency (HF) nutrient and biogeochemical monitoring in the Sacramento–San Jo

This report is the first in a series of three reports that provide information about high-frequency (HF) nutrient and biogeochemical monitoring in the Sacramento–San Joaquin Delta of northern California (Delta). This first report provides an introduction to the reasons for and fundamental concepts behind collecting HF measurements, and describes the benefits associated with a real-time, continuous, HF, multi-parameter water quality monitoring station network that is co-located with flow stations. It then provides examples of how HF nutrient measurements have improved our understating of nutrient sources and cycling in aquatic systems worldwide, followed by specific examples from the Delta. These examples describe the ways in which HF instrumentation may be used for both fixed-station and spatial assessments. The overall intent of this document is to describe how HF measurements currently (2017) are being used in the Delta to examine the relationship between nutrient concentrations, nutrient cycling, and aquatic habitat conditions.

An unprecedented coastwide toxic algal bloom linked to anomalous ocean conditions

American Geophysical Union (AGU) | October 9th, 2016

A coastwide bloom of the toxigenic diatom Pseudo-nitzschiain spring 2015 resulted in the largest recorded outbreak of the neurotoxin, domoic acid, along the North Ameri

A coastwide bloom of the toxigenic diatom Pseudo-nitzschiain spring 2015 resulted in the largest recorded outbreak of the neurotoxin, domoic acid, along the North American west coast. Elevated toxins were measured in numerous stranded marine mammals and resulted in geographically extensive and prolonged closures of razor clam, rock crab, and Dungeness crab fisheries. We demonstrate that this outbreak was initiated by anomalously warm ocean conditions. Pseudo-nitzschia australis thrived north of its typical range in the warm, nutrient-poor water that spanned the northeast Pacific in early 2015. The seasonal transition to upwelling provided the nutrients necessary for a large-scale bloom; a series of spring storms delivered the bloom to the coast. Laboratory and field experiments confirming maximum growth rates with elevated temperatures and enhanced toxin production with nutrient enrichment, together with a retrospective analysis of toxic events, demonstrate the potential for similarly devastating ecological and economic disruptions in the future.

Analog Model Study of the Ground-Water Basin of the Upper Coachella Valley, California

U.S. Geological Survey (USGS) | July 18th, 1974

An analog model of the ground-water basin of the upper Coachella Valley was constructed to determine the effects of imported water on ground-water levels. The mod

An analog model of the ground-water basin of the upper Coachella Valley was constructed to determine the effects of imported water on ground-water levels. The model was considered verified when the ground-water levels generated by the model approximated the historical change in water levels of the ground-water basin caused by man's activities for the period 1936-67. The ground-water basin was almost unaffected by man's activities until about 1945 when ground-water development caused the water levels to begin to decline. The Palm Springs area has had the largest water-level decline, 75 feet since 1936, because of large pumpage, reduced natural inflow from the San Gorgonio Pass area, and diversions of natural inflows at Snow and Falls Creeks and Chino Canyon starting in 1945. The San Gorgonio Pass inflow had been reduced from about 13,000 acre-feet in 1936 to about 9,000 acre-feet by 1967 because of increased ground-water pumpage in the San Gorgonio Pass area, dewatering of the San Gorgonio Pass area that took place when the tunnel for the Metropolitan Water District of Southern California was drilled, and diversions ofsurface inflow at Snow and Falls Creeks. In addition, 1944-64 was a period of below-normal precipitation which, in part, contributed to the declines in water levels in the Coachella Valley. The Desert Hot Springs, Garnet Hill, and Mission Creek subbasins have had relatively little development; consequently, the water-level declines have been small, ranging from 5 to 15 feet since 1936. In the Point Happy area a decline of about 2 feet per year continued until 1949 when delivery of Colorado River water to the lower valley through the Coachella Canal was initiated. Since 1949 the water levels in the Point Happy area have been rising and by 1967 were above their 1936 levels. The Whitewater River subbasin includes the largest aquifer in the basin, having sustained ground-water pumpage of about 740,000 acre-feet from 1936 to 1967, and will probably continue to provide the most significant supply of ground water for the upper valley. The total ground-water storage depletion for the entire upper valley for 1936-67 was about 600,000 acre-feet, an average stor age decrease of about 25,000 acre-feet per year since 1945. Transmissivity for the Whitewater River subbasin ranges from 360,000 gal- lons per day per foot (near Point Happy) to 50,000 gallons per day per foot, with most of the subbasin about 300,000 gallons per day per foot. In contrast, the transmissivities of the Desert Hot Springs, Mission Creek, and Garnet Hill sub-basins generally range from 2,000 to 100,000, but the highest value, beneath the Mission Creek streambed deposits, is 200,000 gallons per day per foot; the transmissivity for most of the area of the three subbasins is 30,000 gallons per day per foot. The storage coefficients are representative of water-table conditions, ranging from 0.18 beneath the Mission Creek stream deposits to 0.06 in the Palm Springs area. The model indicated that the outflow at Point Happy decreased from 50,000 acre-feet in 1936 to 30,000 acre-feet by 1967 as a result of the rising water levels in the lower valley. The most logical area to recharge the Colorado River water is the Windy Point-Whitewater area, where adequate percolation rates of 2 4 acre-feet per acre per day are probable. The Whitewater River bed may be the best location to spread the water if the largest part of the imported water can be recharged during low-flow periods. The area in sec. 21, T. 2 S., R. 4 E., would be adequate for the smaller quantities of recharge proposed for the Mission Creek area. Projected pumpage for the period 1968-2000 was programed on the model with the proposed recharge of Colorado River water for the same period. The model indicated a maximum water-level increase of 200 feet above the 1967 water level at Windy Point, the proposed recharge site, by the year 2000, a 130-foot increase by 1990, and a 20-foot increase by 1980. The model indicated that the proposed quantities of recharge will beneficially affect the ground-water system to Palm Desert by 1980, to Point Happy by 1990, and possibly to the Coachella Canal by 2000. The model indicated that the upper and lower valleys are within the same hydrologic system, and it has been proposed that the model be extended to the Salton Sea. On the basis of the available analyses, changes in the quality of ground water in the Whitewater River subbasin after recharge apparently will be, as a first approximation, proportional to the ratio in which the quantity of recharge and the quantity of ground water are mixed. Where mixing does not occur, the quality of the recharge water will probably not be greatly changed by ion-exchange phenomenon.

Analyses of Rotary Screw Trap Sampling of Migrating Juvenile Chinook Salmon in the Stanislaus River, 1996-2005

Delta Stewardship Council (Delta Council) | August 1st, 2006

Analysis of Potential Water-Supply Management Options, 2010-60, and Documentation of Revisions to the Model of the Irwin Basin Aquifer System, Fort Irwin National Training Center, California

U.S. Geological Survey (USGS) | October 31st, 2014

The Fort Irwin National Training Center is considering several alternatives to manage their limited water-supply sources in the Irwin Basin. An existing three-dimensional

The Fort Irwin National Training Center is considering several alternatives to manage their limited water-supply sources in the Irwin Basin. An existing three-dimensional, finite-difference groundwater-flow model—the U.S. Geological Survey’s MOD-FLOW—of the aquifer system in the basin was updated and the initial input dataset was supplemented with groundwater withdrawal data for the period 2000–10. The updated model was then used to simulate four combinations, or scenarios, of groundwater withdrawal and recharge over the next 50 years (January 2011 through December 2060). The scenarios included combinations of continuing withdrawals from currently active production wells, supplementing any increases in demand with withdrawals from an inactive production well, reducing withdrawal amounts and rates, and reducing the discharge of treated wastewater to infiltration ponds that provide a recharge source to the underlying aquifer. Results of the simulations indicated that, depending on the scenario implemented, groundwater levels would rise (over the next 50 years) from 40 feet to as much as 65 feet in the northwestern part of the Irwin Basin, and from 5 feet to 10 feet in the southeastern part.

Annual Report Clean Water State Revolving Fund and the Water Quality, Supply, and Infrastructure Improvement Act of 2014 State Fiscal Year 2017-2018

California State Water Resources Control Board (SWRCB) | December 30th, 2018

The California State Water Resources Control Board (State Water Board), Division of Financial Assistance (DFA) presents the Clean Water State Revolving Fund (CWSRF) annua

The California State Water Resources Control Board (State Water Board), Division of Financial Assistance (DFA) presents the Clean Water State Revolving Fund (CWSRF) annual report for State Fiscal Year (SFY) 2017-18. The State Water Board provided approximately $707 million in new CWSRF financing to 44 projects in SFY 2017-18, which represent a wide variety of projects eligible under the CWSRF. This report describes how the State Water Board met the objectives identified in the SFY 2017-18 CWSRF Intended Use Plan (IUP). 

Annual Report of Activities October 1, 2013 to September 30, 2014, American River Group (ARG)

Delta Stewardship Council (Delta Council) | September 30th, 2014

Annual Report of Activities October 1, 2013, to September 30, 2014, Delta Operations for Salmonids and Sturgeon (DOSS) Technical Working Group

Delta Stewardship Council (Delta Council) | October 31st, 2014