Water Quality
Water quality is a critical public health and water supply concern in the San Gabriel Valley. Pollution and contamination not only endanger local water sources but also require extensive and costly remediation efforts. Ensuring clean water is essential for both residents and businesses, making water treatment and protection a top priority for Southern California, particularly in the San Gabriel Basin. Proactive management and sustainable practices are vital to maintaining a reliable and safe water supply for the region.
In the 1970s, industrial pollution contaminated numerous wells, prompting Upper District and local agencies to take action to ensure clean water. The severity of the issue became clear in 1979 when high levels of volatile organic compounds (VOCs) were found near an industrial complex in Azusa. Further investigations confirmed widespread VOC contamination affecting the San Gabriel Basin.
In response, the San Gabriel Basin Water Quality Authority (WQA) was established under SB 1679 on February 11, 1993, to develop and fund groundwater treatment programs. Since then, over 30 full-time treatment facilities have been built, removing more than 100,000 pounds of contaminants to safeguard the region’s water supply. The total cost of construction and operation is estimated at $1.2 billion.
Upper District is a WQA member, with a representative serving on its seven-member governing board. To learn more about WQA’s role and operations, click below.
Trust Your Tap Video
Tap water in the San Gabriel Valley is safe to drink! Local water suppliers rigorously treat, filter, and test the water multiple times daily to ensure its quality before it reaches your home.
Your water consistently meets or exceeds federal drinking water standards, ensuring safety and reliability. Learn more about the process by watching this video!
Per-and Polyflournalky Substances (PFAS) and Contaminants of Emerging Concern
Consistent with our mission to meet the region’s needs for reliable, high quality, and affordable water, Upper District continues to work with other water agencies to ensure that the San Gabriel Valley has a safe water supply. In light of the growing concern over the presence of emerging contaminants known as PFAS, below are fact sheets, briefing materials and visuals that may be helpful when answering questions about these chemicals. Click on the links below.
Supporting Documents
- PFAS Presentation from Metropolitan Water District
- PFAS Fact Sheet
- PFAS Frequently Asked Questions
- PFAS Briefing from American Water Works Association
- PFAS Cycle Infographic
- PFAS Summary of State Regulation to Protect Drinking Water
- PFAS Treatment
- PFAS Monitoring, Sampling, Analysis
- EPA Methods for PFAS in Drinking Water
