“Water” We Drinking?

Across the country, having access to safe drinking water is a public health concern. This concern especially impacts students, who often have limited control over their drinking water sources and lack the resources to conduct water quality testing.

Given that studies have found contaminated drinking water in public schools from the elementary through high school levels in all fifty states, any fear students may have of drinking unfiltered tap water seems warranted.[1]An investigation by the Associated Press revealed that contamination is not limited to schools in cities like Flint, Michigan, for example, where pipe corrosion leached high levels of lead into the water, or from schools that utilize well water (approximately 10% of schools across the country). Due to the high cost of repairing our aging water infrastructure systems, as well as the low accountability and inconsistent standards across local, state and federal governments, the Environmental Protection Agency estimated that about 20% of schools violated the Safe Water Drinking Act between 2007 and 2017.[2]

 Concerns of such problems affect families at Stanford as well. Over the summer, parents of Stanford students suggested that campus water contains excessive ions and cautioned against drinking water straight from the tap, as they were concerned it could cause cancer or other deficiencies. As a result, some parents recommended buying a filter, while others suggested drinking only bottled water.

Myth or Reality?

Stanford takes several precautions to ensure the safety of campus water. Stanford’s 25-person Water Resources and Civil Infrastructure (WRCI) group manages the Domestic Water System for drinking water, as well as the Lake Water System for non-potable irrigation water, Storm Drain, and Sewer Systems. In addition to having sediment filtration and ion aeration at a water treatment plant, Stanford’s water is further treated with chloramine (a mixture of chlorine and ammonia) and fluoride to protect against bacteria and viruses, as well as lessen tooth decay. Since 2004, the San Francisco Public Utilities Commission (SFPUC) has switched from chlorine to chloramine due to the compound’s stability and to reduce disinfectant byproducts such as trihalomethanes, many of which are considered “known” carcinogens in California. This means that when it comes to cancer risks, SFPUC water is safer than chlorinated water.[3],[4]

According to Brian Manning, Senior Environmental Engineer of the WRCI group, any worries about the quality of Stanford’s water are unmerited. “SFPUC’s Hetch Hetchy water supply is one of the most protected and pristine watersheds in the country,” Manning stated.[5]In case of an emergency, Stanford also has its own wells that it can source water from, but as Manning said, the university purchases its water from SFPUC, which in turn obtains its water from snowmelt flowing from Hetch Hetchy Reservoir in Yosemite National Park, down the Tuolumne River and down to the San Joaquin River, as well as local reservoirs in Santa Clara, San Mateo, and Alameda counties to ensure stability.


Water flow from the Hetch Hetchy Reservoir to San Francisco


The SFPUC water is in fact so pure that the city of San Francisco repackages filtered SFPUC water to sell its own bottled water brand called Hetch Hetchy Mountain Water, meaning that some local bottled water stems from the same source as Bay Area tap water. However, Hetch Hetchy Mountain bottled water aside, students may generally be better off sticking with drinking Stanford tap water.

“Drinking water, including bottled water, even if compliant with all regulatory requirements, may be expected to contain small amounts of some contaminants (from the water source and treatment),” Manning said. Though tap water quality is heavily regulated, there are fewer regulations placed on bottled water, and thus an increased risk of potential carcinogens. For example, a study by the State University of New York examined 259 bottles of water from various brands and countries, and estimated that 93% of the bottled water contains microplastics.[6]Though the effect of microplastics on human health is unclear, several marine organisms such as mussels and oysters, and land animals such as mice have been shown to have adverse reactions to these plastic particles.[7]Since bottled water is regulated by the Food and Drug Administration, unlike tap water which is more strictly regulated by the Environmental Protection Agency, bottled water companies are not required to complete lab testing nor reveal what contaminants their water may contain. [8]

“SFPUC and Stanford WRCI staff sample water quality on a daily basis, ensuring it consistently meets federal and state water quality standards. No actions are typically needed to be taken at the tap here at Stanford University, although some water users may prefer to use filters of some kind for sensitive health reasons or personal aesthetic preference,” Manning remarked. WRCI publishes annual reportsof water quality and changes in measures such as pH, hardness, conductivity, nitrates, and alkalinity. These measurements have minor shifts throughout the year, but all remain at safe levels, although they may impact sensitive laboratory processes on campus.

A looming threat

The biggest threat to Stanford’s water supply, then, may not be pollutants, but rather an environmentalist movement. The Hetch Hetchy Reservoir was dammed after the 1906 San Francisco Earthquake made visible that the Bay Area’s existing water supply was inadequate. However, the Restore Hetch Hetchy movement has argued that San Francisco does not have the right to flood Hetch Hetchy, and thus, should demolish the dam.[9] Though it worried San Francisco officials, a 2012 ballot measure aimed at buoying this movement failed, with just 22% of voters supporting the measure. The Restore Hetch Hetchy movement is currently fighting its battle in court, contending that the city of San Francisco broke the 1913 Raker Act, the law that allowed the reservoir to be dammed in the first place. Although they lost their battle at the Court of Appeals, Restore Hetch Hetchy is poised to take their battle to the U.S. Supreme Court with the help of lawmakers. If the movement succeeds, San Francisco, and by extension, Stanford may have to obtain water from lower-quality reservoirs.


Top: “Hetch Hetchy Reservoir 05”by Blake Carroll is in the Public Domain. Bottom: “Hetch Hetchy Valley”by Isaiah West Taber is in the Public Domain,

Top: Hetch Hetchy Reservoir, currently, after it was dammed and flooded. Bottom: what Hetch Hetchy Valley used to be and what environmentalist advocates want to restore it to.

 The future of water infrastructure

The WRCI’s hard work maintaining water quality makes Stanford’s tap water perfectly safe to drink, just like much of the tap water in the US. However, water quality is still a public health concern in certain parts of the country. Much of the country’s water infrastructure is reaching the end of its useful lifespan, with repairs expected to cost up to a trillion dollars in the next 25 years. Significant investments need to be undertaken to ensure we do not see an increase in public health scares. Improved infrastructure will also help to prevent leaks and water main breaks, which wastes about six billion gallons of treated water every day in the US (nearly 20% of the country’s drinking water needs!).[10]However, due to rising costs of necessary investments in modern technology such as Internet of Things (IoT devices)  to monitor pipes, it will take 200 years to replace our current water infrastructure, despite the fact that the expected lifespan of most water systems is only 75-100 years.[10,11]

In addition, water treatment can take up to 35% of a city’s electricity output, and one of the most energy-consuming parts of that process is aerating the water so that aerobic bacteria can remove waste through respiration. This is why scientists at Stanford hope to make the process of water treatment cheaper and less energy-intensive. At Stanford’s Codiga Resource Recovery Center(CR2C), an institution designed to improve water and energy resource recovery systems, researchers developed a novel method using anaerobicbacteria to break down waste, so that no aeration is necessary. The bacteria will release methane, as a byproduct, which can then be used as a source of fuel for the plant, in compounds for bio-plastics, or as an additive in aquaculture feed to improve fish health.[12,13]Although the process is slow, the Codiga Center hopes to test these technologies and implement them across the United States in the coming years. The hope is that as water infrastructure is replaced and repaired across the country, it will be done with more modern and efficient technology.


  1. Chen, G. (2017) Do Public Schools Have Tap Water Safe to Drink? Public School Review. Retrieved November 3, 2018, from https://www.publicschoolreview.com/blog/do-public-schools-have-tap-water-safe-to-drink
  2. AP. (2009) School Drinking Water Unsafe CBS News.Retrieved November 3, 2018, from https://www.cbsnews.com/news/ap-school-drinking-water-unsafe/
  3. SFPUC. (2013) Questions Regarding Disinfection By-products. San Francisco Public Utilities Commission. Retrieved November 3, 2018, from https://www.sfwater.org/modules/showdocument.aspx?documentid=4132
  4. SFPUC. (2018) Chloramine. San Francisco Public Utilities Commission. Retrieved November 3, 2018, from https://www.sfwater.org/index.aspx?page=357
  5. Manning, B., Senior Environmental Engineer (2019, January 10). Stanford Water Quality. [Personal Interview]
  6. McCarthy, N. (2018) Study Finds Microplastics in 93% of Bottled Water. Forbes.Retrieved November 3, 2018, from https://www.forbes.com/sites/niallmccarthy/2018/03/16/study-finds-microplastics-in-93-percent-of-bottled-water-infographic/#758cbe0273fa
  7. Reviewed by Robertson, R. (2018) Are Microplastics in Food a Threat to Your Health? Healthline Media. Retrieved November 3, 2018, from https://www.healthline.com/nutrition/microplastics#health-effects
  8. Goodman, S. (2009) Fewer Regulations for Bottled Water Than Tap, GAO Says. The New York Times.Retrieved November 3, 2018, from https://archive.nytimes.com/www.nytimes.com/gwire/2009/07/09/09greenwire-fewer-regulations-for-bottled-water-than-tap-g-33331.html
  9. Thorwaldson J. (2017) Off Deadline: Is ‘Restore Hetch Hetchy’ a pipe dream or a living vision? Palo Alto Weekly. Retrieved January 15, 2018, from https://www.paloaltoonline.com/news/2017/10/15/off-deadline-is-restore-hetch-hetchy-a-pipe-dream-or-a-living-vision
  10. ASCE (2017) 2017 Infrastructure Report Card. American Society of Civil Engineers.Retrieved March 7, 2019, from https://www.infrastructurereportcard.org/wp-content/uploads/2017/01/Drinking-Water-Final.pdf
  11. West, M. (2017) On the Brink: Dealing with America’s Aging Water Infrastructure. Water Online.Retrieved March 7, 2019, from https://www.wateronline.com/doc/on-the-brink-dealing-with-america-s-aging-water-infrastructure-0001
  12. Zweig, D. (2017) Stanford’s Codiga Center Aims to Transform Water Treatment. Stanford Energy Journal. Retrieved January 15, 2018 from https://sej.stanford.edu/stanfords-codiga-center-aims-transform-water-treatment
  13. Stanford University. (2017) William and Cloy Codiga Resource Recovery Center. CR2C.Retrieved January 15, 2018 from http://web.stanford.edu/group/cr2c/