From its breathtaking coastal landmarks and iconic views of the Golden Gate Bridge to its integral role in the tech industry, the San Francisco Bay Area is one of the most heavily visited areas in the world. Whether you’re a local or just passing through, here’s what you should know about San Francisco’s drinking water. 

TL;DR: is San Francisco’s tap water safe to drink? 

• The majority of San Francisco’s tap water comes from the Tuolumne River, a pristine waterway near Yosemite Valley. 
• San Francisco’s water is regularly tested to ensure it meets state and federal guidelines; however, these guidelines may not be enough. 
• Even though it is relatively high in quality and legally safe to drink, San Francisco’s tap water still may have issues with lead, PFAS, microplastics, and chromium-6, so you should run it through a reusable filtering water bottle or filtering water pitcher for safety. 

What you need to know about SF tap water

San Francisco’s tap water is generally considered to be higher in quality and better tasting than many other drinking waters around the nation, and much of this is due to its water sources. The majority of its drinking water comes from the beautiful Tuolumne River near Yosemite and the Hetch Hetchy Reservoir. However, it is also mixed with groundwater from sources more local to the Bay Area before it is processed and distributed. 

Like other cities in the Golden State, San Francisco also dedicates plenty of resources to ensuring that its tap water is tested against California’s Water Quality Regulations and standards set by the United States government and CDC to ensure that its water is safe for consumption. In 2022 alone, the San Francisco Water Quality Report stated that the drinking water went through a whopping 94,230 drinking water tests to ensure its quality. As a result, San Francisco’s tap water is generally safe. However, some issues can still be picked up in the water system, and it’s always a good idea to run it through a water filter first. 

Lead contamination

One of the first and most serious areas of potential concern in San Francisco’s tap water is the potential for lead contamination.  

Lead is a heavy metal that was historically used to build water lines and fixtures. This practice was discontinued when researchers found that lead was a neurotoxin and was linked to several serious health concerns, especially in children. As a result, San Francisco removed and replaced its known lead service pipes in the 1980s and frequently tests for lead levels in drinking water. 

However, it’s important to note that “legal” isn’t necessarily the best gauge for how safe tap water is. In 2017, news broke that about half of San Francisco schools were suspected to have some level of lead in their tap water. While not all the schools tested for levels higher than the “allowable” amount, many health experts agree that there is no safe level of lead exposure. 

It’s also clear that issues of lead contamination are not completely handled even in today’s age of strict testing. Even as recently as December 2022, it was found that Buena Vista Horace Mann K-8 Community School had levels of lead that were higher than acceptable in three of their school faucets. 

Chromium

High chromium levels are another potential water quality issue in San Francisco and California at large. Chromium-6 (sometimes called hexavalent chromium) is a naturally occurring chemical that is sometimes linked to cancer cases upon consumption. Unfortunately, there is no current California limit for chromium-6. Instead, there is a standard for total chromium, which also includes other forms of chromium like trivalent chromium which is not thought to be dangerous. 

This can lead to confusing and potentially problematic issues with the current chromium-6 levels. For example, a report published by the San Francisco Public Utilities Commission stated that the amount of chromium-6 found in San Francisco’s water supply was in very low levels that were less than the former state maximum contaminant level of 10 PPB. However, an independent analysis by the nonprofit Environmental Working Group reported that the amount of chromium found in SF city’s tap water was over 4.5 times the amount that they would consider safe based on their own independent health guideline. 

PFAS

“Forever chemicals” poly-fluoroalkyl substances are also becoming more and more highlighted as a potential concern for tap water, both in San Francisco and throughout the world. These man-made substances are used in various manufacturing and production processes. They get their “forever chemical” nickname because they do not naturally degrade, and can instead contaminate and pollute the environment and local waterways. 

While the state of California does a generally good job of monitoring and limiting these potentially dangerous chemicals, issues are still prevalent throughout the Bay Area. For example, manufacturing facilities in nearby Hayward, Vacaville, and Berkeley were all issued notices by the Center of Environmental Health because they were all found to be discharging PFAS/PFOA into groundwater. 

However, the scariest thing about PFAS and other forever chemicals is that we just don’t have enough information right now to know just how much of it is actually in our waterways, or what kinds of risks they can pose in the long run (although some evidence has already found links to cancer, heart health issues, and immune system issues). There are more than 9,000 different chemicals that fall into the PFAS category, and some researchers in the Bay are concerned about their prevalence as well as their effects on marine life and coastal communities that depend on the waterways for food and economy. 

Microplastics

Finally, it’s well worth mentioning the issue of microplastics, or minuscule pieces of plastic that eventually make their way into the waterways. A report by the San Francisco Estuary Institute & The Aquatic Science Center conducted a study on the prevalence of microplastics in the Bay Area and found that microplastics could enter the waterways via storm-driven runoff from the cities.  

Luckily, California became the first state to begin monitoring microplastics in drinking water. Even still, it’s worth considering if you’re going to be drinking straight from the tap. 

The Bottom Line: San Francisco tap water quality is fairly good, but you should still filter it before you drink it to be safe. 

The majority of San Francisco’s tap water comes from the beautiful Tuolumne River and Hetch Hetchy Reservoir, and it is also subject to plenty of testing before it reaches your tap. Unfortunately, some water quality issues still remain due in large part to outdated plumbing and modern-day pollution. 

Take advantage of San Francisco’s naturally delicious water sources by filtering it first! Find one of San Francisco’s many water fountains and run your drinking water through a filtering bottle like LARQ’s Bottle Filtered, which can remove common contaminants like lead, heavy metals, chlorine, and particulates while you’re on the go. If you’re a Bay Area native, use a filtering water pitcher like the LARQ Pitcher PureVis to filter out common pollutants and purify the water in your home.