Independent, objective, nonpartisan research
Blog Post · January 16, 2018

Information Gaps Hinder Progress on Safe Drinking Water

Fish and Wildlife Scientific Aid Brian Bettencourt (left) records data while Environmental Scientist Evan MacKinnon (right) reads off water quality parameters from a multi-parameter water quality meter at a well in Sutter County, California for the Department of Water Resources

The short answer to the question, “How many Californians lack access to safe drinking water?” is, “Too many.” Everyone deserves to have ready access to clean water. But understanding the extent of the problem is less straightforward. Some recent strides have been made in compiling data on communities with drinking water violations, but more work is needed to help scope solutions, prioritize actions, and track progress.

The biggest data gaps are for domestic wells or very small water systems that are not regulated by the federal Safe Drinking Water Act (SDWA). Estimates of this population vary widely—from 1 to 2 million—and the state lacks good data on how many of these residents face water safety problems. Developing tracking systems for this population is an ongoing priority.

California also has data gaps for the thousands of water systems regulated by the SDWA that serve the vast majority of the state’s residents: community water systems with more than 15 connections and other public systems such as schools. The State Water Board’s new Human Right to Water (HR2W) portal reports monthly compliance, population served, location, and pollutants present in the water. It provides an easier way to see which systems are currently failing to meet safe drinking water standards. But information gaps in the new system make it hard to translate the data into action.

As of November 2017 this portal showed that just over 300 water systems, serving roughly 490,000 people, were out of compliance. About 13% of these systems are schools, serving roughly 13,000 people; the rest are community water systems. More than 90% of the non-compliant community systems are small, serving fewer than 3,300 people; 75% serve fewer than 500 people. Small systems are more likely to violate drinking water standards and to lack the technical, financial, and managerial capacity to resolve these issues on their own.

While the HR2W portal provides a valuable snapshot, it falls short of providing the detail needed to understand and track drinking water challenges in public systems. The information is not organized to enable users to see relevant patterns, such as long-running violations or multiple violations per system. Knowledge of safe drinking water regulations is required to parse which systems are in the most trouble. This tool would be more useful if the data were summarized by water system, with an overview of how long a system has been out of compliance and how serious the violations are.

A useful model for organizing safe drinking water data comes from the US Environmental Protection Agency, which publishes Enforcement and Compliance History Online (ECHO) to track a variety of regulatory programs. ECHO reports the number of quarters within the past three years in which drinking water systems were out of compliance. It also uses a point system to reflect the seriousness of the problem. For instance, systems exceeding standards for nitrate and pathogens get 10 points per violation, since EPA considers those problems most acute. Systems exceeding less serious standards get 5 points per violation, and each monitoring and reporting violation gets 1 point. Points accumulate for issues that remain unaddressed. ECHO provides a compliance summary for each system, and enables the user to drill down into violation details.

Using information from ECHO, we find that more than 80% of California’s non-compliant drinking water systems, serving 280,000 residents, have been out of compliance for at least three years (see figure). Nearly three-quarters of these systems have at least 20 unaddressed violation points. As expected, problems are most persistent and severe in small—and especially very small—systems. And they are most prevalent in the San Joaquin Valley—home to roughly 10% of California’s population and nearly half of the state’s non-compliant water systems.

California should draw from the federal ECHO model to improve its HR2W. The state might want to customize the ECHO point system to reflect local conditions―for instance, where state standards are stricter than federal standards. The state is working on adding new metrics, such as water affordability, to HR2W. Additional priorities include providing indicators of progress in addressing violations, such as funds allocated. And instead of flagging only systems that have a safety violation, the state could track systems that are behind on monitoring and reporting because this could foreshadow future violations of water quality standards.

More accessible and transparent data would help build momentum for action. This is especially important in light of ongoing efforts to create a sustainable funding source for safe drinking water in affected communities—such as the current legislative proposal to levy surcharges on agricultural chemicals and urban water bills. Such a program would require a robust tracking system for efficient governance of the funds. With some improvements, HR2W could help prioritize actions and investments in communities that need it most.


Safe Drinking Water Water Supply Water, Land & Air
Public Policy Institute of California