Drinking water contamination isn’t something most people think about on a daily basis, especially in the United States. However, the threat of water contamination is always a possibility. After the terrorist attacks in 2001, identifying ways to secure the nation’s drinking water distribution systems became a larger priority because, whether intentional or accidental, contaminated drinking water can have serious consequences on public health, critical infrastructure, the economy, and the environment. The reality is, with multiple points of access and no easy way to detect contaminants in a timely manner, water distribution systems are vulnerable to potential security threats. To address this concern, the United States Environmental Protection Agency (EPA) funded monitoring and surveillance pilot programs in five U.S. cities as part of a larger Water Security Initiative.
With approximately 1,200 miles of mains and 400 million gallons of storage (over 5 days of average demand) spread across dozens of storage facilities, the potential exists for contamination, both intentional and unintentional, as well as other types of water quality and operational issues
Continuing our series on the EPA’s Contamination Warning System (CWS) pilot programs, an interesting case study with San Francisco, California, demonstrates how the city implemented a comprehensive system to protect its drinking water. The San Francisco Public Utilities Commission (SFPUC), the third largest municipal utility in California, was granted $8 million to fund its pilot program. SFPUC contributed approximately $3.7 million to the project, bringing the total budget to approximately $12 million.
Serving 2.6 million residential, commercial, and industrial customers in the Bay Area, SFPUC has made it a priority to invest in the city’s drinking water sources to ensure that high water quality is achieved. The Hetch Hetchy Reservoir, fed by Sierra mountain snowmelt, is one of the most pristine drinking water sources in the United States and an important element of San Francisco’s water quality (supplying about 85 percent of the city’s water). As part of its water quality strategy, SFPUC systematically evaluates the risk to its water quality from source to tap. The CWS pilot gave SFPUC an opportunity to further increase water safety, addressing not only existing risks but also considering potential risks.