Drinking Water Treatment and Distribution (Resource Management Strategy)

California Department of Water Resources (DWR) | July 29th, 2016

Providing a reliable supply of safe drinking water is the primary goal of public water systems in California. To achieve this goal, public water systems must develop and

Providing a reliable supply of safe drinking water is the primary goal of public water systems in California. To achieve this goal, public water systems must develop and maintain adequate water treatment and distribution facilities. In addition, the reliability, quality, and safety of the raw water supply are critical to achieving this goal. In general, public water systems depend greatly on the work of other entities to help protect and maintain the quality of the raw water supply. Many agencies and organizations have a role in protecting water supplies in California. For example, the basin plans developed by the regional water quality control boards recognize the importance of this goal and emphasize protecting water supplies — both groundwater and surface water. A public water system is defined as a system for the provision of water for human consumption, through pipes or other constructed conveyances, which has 15 or more service connections or regularly serves at least 25 individuals daily at least 60 days of the year (Health and Safety Code Section 116275[h]). Public water systems are divided into three principle classifications: community water systems (CWS), non-transient non-community (NTNC) water systems, and transient non-community (TNC) water systems. As the name indicates, CWS serve cities, towns, and other residential facilities occupied by year-round users. Examples include everything from apartment complexes served by their own wells to systems serving California’s largest cities. NTNC systems are public water systems that are not CWS and provide water to the same non-residential users daily for at least 180 days of the year. Examples include schools, places of employment, and institutions. TNC systems are places that provide water for a population that mostly comes and goes. Examples include campgrounds, parks, ski resorts, rest stops, gas stations, and motels. CWS serve approximately million of the estimated 37.7 million people throughout the state, or 97 percent of the state’s population. The remaining estimated 1.1 million people in the state (3 percent of the population) receive their drinking water from private wells serving their individual residences or from other sources. Virtually every Californian and visitor to the state will use drinking water from a regulated public water system through their work, while on vacation, or while traveling through the state.

Drought and Equity in California

Pacific Institute | January 9th, 2017

Drought and Equity in California is the first statewide analysis of the impacts of the drought on California’s most vulnerable communities. This report provides informa

Drought and Equity in California is the first statewide analysis of the impacts of the drought on California’s most vulnerable communities. This report provides information community groups can use to advocate for their own interests, as well as to inform policymakers and other decision-makers interested in crafting more effective drought response strategies, particularly to address the needs of the state’s most vulnerable communities. The report finds that during the state’s ongoing drought, water shortages and price hikes affected access to safe, affordable water for Californians, with substantial impacts on low-income families and communities burdened with environmental pollution. The report also examines the effects of a rapidly declining salmon population on commercial and tribal fishermen and finds that the decline and variability of salmon populations during droughts has impacted those dependent on the fish for income, food, and cultural traditions.

Drought and Equity in the San Francisco Bay Area

Pacific Institute | June 29th, 2016

California’s ongoing drought has wide-reaching impacts, from how we grow crops to the price of electricity. Often overlooked is its impact on disadvantaged communities.

California’s ongoing drought has wide-reaching impacts, from how we grow crops to the price of electricity. Often overlooked is its impact on disadvantaged communities. The Pacific Institute and The Environmental Justice Coalition for Water (EJCW) conducted community-based participatory research with eight Bay Area community-based groups to explore and document the drought’s impacts on low-income people in the San Francisco Bay Area. Through a series of collaborative meetings, surveys, and in-depth analyses of data, the group produced a groundbreaking report that sheds light on specific drought-related hardships faced by low-income residents and offers recommendations for mitigating those impacts. “This report is the first examination of the drought’s impacts on low-income communities in the Bay Area,” says Colin Bailey, Executive Director of EJCW. “Contrary to the conventional wisdom, the report shows the same hardships that befall California’s more rural communities are present in urban areas as well. The report calls on decision makers to account for and address these inequities in our drought responses.” The project team examined available data on drought impacts for the Bay Area, such as the number of households without water. The group identified affordability and water infrastructure conditions as key concerns for low-income communities, along with inequitable water use, whereby wealthier households typically use more water than lower income households. These are persistent concerns in many communities but have been exacerbated by the drought.

Drought Management and Climate Adaptation among Small, Self-Sufficient Water Systems in California

California Natural Resources Agency (CNRA) | August 27th, 2018

 Examining human impacts, responses, and challenges to extreme climatic events can give insight into needed directions for climate adaptation to reduce future risks. Thi

 Examining human impacts, responses, and challenges to extreme climatic events can give insight into needed directions for climate adaptation to reduce future risks. This study focuses on the 2012-2016 Drought in California, documenting how small self-sufficient drinking water systems were affected and challenged by, and responded to the extreme event. The majority of small, self-sufficient water systems in the state serve rural, low income communities, and many have low technical, managerial, and financial capacity compared to larger systems. This increases the risk that these drinking water systems will be disproportionately impacted by droughts or other disruptions. To assess the impact of drought on small water systems, we employed an iterative approach to gathering perspectives and experiences from drinking water system managers across the state. The goal of employing these iterative methods is to better understand the breadth and scope of impacts, responses, and barriers to dealing with the 2012- 2016 Drought. The first stage of the data collection involved interviewing managers of drinking water systems, which were transcribed and analyzed using semi-grounded theory methods. To cross-check and advance findings from interviews in additional locations, we conducted three small regional workshops and then a larger policy forum. Multiple data collection methods allowed us to gather insights about experiences from nearly 200 water managers. This project uses local knowledge to document the social dimensions within drinking water systems during the 2012-2016 Drought and expresses the value of local knowledge in reflecting on future drinking water system needs in response to extreme events.  We found that drinking water systems, despite size or government project water reliance, experienced a similar set of drought impact, response, and barrier categories (e.g., water quantity and water quality). However, within these categories, the types of impacts, responses, and barriers differed based on both system size and water source portfolio. Common disadvantages that hinder drought resilience, and thus climate adaptation, of small self-sufficient drinking water systems include: staff capacity; financial burden of revenue loss during drought compounded with increased need for staff time for additional reporting; customer awareness and outreach challenges; and consolidation. We found that consolidation is valuable but in many case needs more state support to implement and incentivize. From a long term perspective, the absence of expressed duty and lack of concern for risks of climate change among water managers indicates a major dearth in adaptation planning among these drinking water systems. Documentation of experiences from the 2012-2016 Drought can be used to inform future planning for droughts and more broadly climate change. 

Economic tradeoff between domestic well impact and reduced agricultural production with groundwater drought management: Tulare County, California (USA), case study

Hydrogeology Journal (Springer) | November 8th, 2021

Formal policy analysis can aid resource management where groundwater is used intensively. Approaches for developing equitable and effective pumping allocations for drough

Formal policy analysis can aid resource management where groundwater is used intensively. Approaches for developing equitable and effective pumping allocations for drought are evaluated in the context of the 2012–2016 drought in Tulare County, California, USA. Potential economic impacts of policy alternatives on two user groups with conflicting interests are considered. Tradeoffs between losses of agricultural profit and response costs for domestic wells that run dry are estimated for various maximum groundwater depth policies. A welfare maximizing approach for identifying policies that limit depth to groundwater is evaluated and found to be ineffective because agricultural opportunity costs are much larger than domestic well costs. Adding a fee for additional drought groundwater pumping is proposed as a more impactful and balanced management policy approach. For the case study presented, a fee range of $300 to $600/acre-foot ($300–$600/1,233 m3) yielded an effective groundwater management policy for reducing domestic well impacts from drought and balancing agricultural impacts of drought with the need to replenish additional drought pumping in wetter years. Recent management policies enacted in the study area agree with this finding. These results may provide a useful perspective for analytically examining and developing groundwater management policies near the study area and elsewhere.

Environmental Justice in California Government

State of California | October 1st, 2003

In California, we have spent over a century and billions of dollars to preserve and protect the environment for current and future generations. The EJ movement asks us to

In California, we have spent over a century and billions of dollars to preserve and protect the environment for current and future generations. The EJ movement asks us to put real people in that environment, particularly the most vulnerable populations such as ethnic minorities, low-income persons, the young and the elderly. In a nutshell, EJ can be said to be the vision and process of creating socially just, sustainable human and ecological systems, where all participate fully in decisions affecting their lives. The Governor’s Office of Planning & Research (OPR) assists the Governor and the Administration in land use planning, research, liaison with local government, small business advocacy, rural policy, and various interagency taskforces. 1999 legislation defined EJ in California law and also established OPR as the coordinating agency in state government for environmental justice (EJ) efforts. The placement of the central EJ program within OPR demonstrates the Legislature’s understanding that EJ efforts require coordination at the highest level of state government.  Indeed, California is the only state that has placed its EJ effort within the Chief Executive’s Office. The legislation establishing OPR as the “coordinating agency in state government for environmental justice programs” (California Government Code § 65040.12) directs the OPR director to consult with state agencies and interested members of the public and private sectors in this state, coordinate its efforts and share information regarding EJ programs with federal agencies, and review and evaluate any information from federal agencies that is obtained as a result of their respective regulatory activities. This policy report is intended to provide a brief history of EJ, report on the status of OPR's efforts, and provide an outline of EJ findings, goals and policies for future EJ efforts within state government. Much work remains to ensure that the most vulnerable of Californians, including people of color and low-income persons, are treated with dignity and respect regarding environmental decisions. OPR views its work thus far as a modest, although significant beginning.

Environmental Justice Program Implementation for Lahontan Region

Lahontan Regional Water Quality Control Board (LRWQCB) | January 30th, 2015

The Lahontan Regional Water Quality Control Board (Lahontan Water Board) reviewed how environmental justice (EJ) is conducted in the region and examined new ways to impro

The Lahontan Regional Water Quality Control Board (Lahontan Water Board) reviewed how environmental justice (EJ) is conducted in the region and examined new ways to improve our efforts to benefit the disadvantaged communities in our region. The challenges faced by disadvantaged communities (DACs) in the Lahontan region are unique and often different than other DACs in more urban regions. This report provides an assessment of existing efforts to help DACs and catalogs EJ concerns. In addition, the report includes recommendations to enhance DACs participation in the regulatory process, expand access to funding and technical assistance, and improve water quality and drinking water.

Estimating domestic well locations and populations served in the contiguous U.S. for years 2000 and 2010

Science of the Total Environment (Elsevier) | October 15th, 2019

Domestic wells provide drinking water supply for approximately 40 million people in the United States. Knowing the location of these wells, and the populations they serve

Domestic wells provide drinking water supply for approximately 40 million people in the United States. Knowing the location of these wells, and the populations they serve, is important for identifying heavily used aquifers, locations susceptible to contamination, and populations potentially impacted by poor-quality groundwater. The 1990 census was the last nationally consistent survey of a home’s source of water, and has not been surveyed since. This paper presents a method for projecting the population dependent on domestic wells for years after 1990, using information from the 1990 census along with population data from subsequent censuses. The method is based on the “domestic ratio” at the census block-group level, defined here as the number of households dependent on domestic wells divided by the total population. Analysis of 1990 data (>220,000 block-groups) indicates that the domestic ratio is a function of the household density. As household density increases, the domestic ratio decreases, once a household density threshold is met. The 1990 data were used to develop a relationship between household density and the domestic ratio. The fitted model, along with household density data from 2000 and 2010, was used to estimate domestic ratios for each decadal year. In turn, the number of households dependent on domestic wells was estimated at the block-group level for 2000 and 2010. High-resolution census-block population data were used to refine the spatial distribution of domestic-well usage and to convert the data into population numbers. The results are presented in two downloadable raster datasets for each decadal year. It is estimated that the total population using domestic-well water in the contiguous U.S. increased 1.5% from 1990 to 2000 to a total of 37.25 million people and increased slightly from 2000 to 2010 to 37.29 million people.

Estimating Lithium Concentrations in Groundwater Used as Drinking Water for the Conterminous United States

American Chemistry Society (ACS) | January 2nd, 2024

Estimating perchlorate exposure from food and tap water based on U.S. biomonitoring and occurrence data

Journal of Exposure Science & Environmental Epidemiology (Springer) | June 23rd, 2010

Human biomonitoring data show that exposure to perchlorate is widespread in the United States. The predominant source of intake is food, whereas drinking water is

Human biomonitoring data show that exposure to perchlorate is widespread in the United States. The predominant source of intake is food, whereas drinking water is a less frequent and far smaller contributor. We used spot urine samples for over 2700 subjects and estimated 24 h intake using new creatinine adjustment equations. Merging data from surveys of national health (NHANES) with drinking water monitoring (UCMR), we categorized survey participants according to their potential exposure through drinking water or food. By subtracting daily food doses of perchlorate from the oral reference dose (RfD), we derive an allowances for perchlorate in tap water for several populations. The calculated mean food perchlorate dose in the United States was 0.081 μg/kg/day compared to 0.101 μg/kg/day for those who also had a potential drinking water component. The calculated 95th percentile doses, typically falling between 0.2 and 0.4 μg/kg/day, were well below the RfD (0.7 μg/kg/day) in all populations analyzed. Children aged 6–11 years had the highest mean perchlorate doses in food (0.147 μg/kg/day), with an additional water contribution of only 0.003 μg/kg/day representing just 2% of exposure. Pregnant women had a mean food dose of 0.093 vs 0.071 μg/kg/day for all women of reproductive age. At the 95th percentile intake for both the total population and women of child-bearing age (15–44), the perchlorate contribution from food was 86% and from drinking water 14% (respectively, 30% and 5% of the RfD). At the mean for the same groups, the food to water contribution ratio is approximately 80:20. We calculate that an average 66 kg pregnant woman consuming a 90th percentile food dose (0.198 μg/kg/day) could also drink the 90th percentile of community water for pregnant women (0.033 l/kg/day) containing 15 μg/l perchlorate without exceeding the 0.7 μg/kg/day reference dose.