Commanded by the moon, high tides push 130 million gallons a day of raw Delaware River water under a nondescript building off State Road in Philadelphia’s Torresdale section.

What looks like a shimmer of blue from a distance flows in as a brown broth of disintegrating leaves, chunks of trees, flopping fish, microbes, minerals, and chemicals. Little more than 24 hours later, that brew has become clear, safe drinking water. It then travels through 3,000 miles of water mains to 1.6 million people in homes, apartments, and businesses for consumption. If all the water mains were laid out end-to-end, they would run to Los Angeles.

The transformation and transportation of 230 million gallons of water a day from the Delaware and Schuylkill at three treatment plants is an engineering and scientific marvel that dramatically improved public health since chlorine was first added to the water here in 1920. Philadelphia’s Water Department is often held up as an urban model, especially for its storm-water protection efforts.

Yet it can’t get that kind of respect from the people the utility wants most to impress, its customers. Nearly 40 percent of city residents refuse to drink water from their taps, saying it tastes bad, or even is bad for them. The belief is especially strong in the poorer parts of America’s poorest big city, where residents spend scarce dollars on the much more expensive option of bottled water.

»THE DELAWARE: The river that made Philadelphia

Slightly more than half of residents rate the quality of their tap water as good, though some still admit they choose bottled. But just 15 percent rate it as excellent.

It’s been almost a century since city water quality was measured by the number of people who died of typhoid fever transmitted through the water. Philadelphia has never faced a public health scandal like that in Flint, Mich., over lead contamination in the water.

Yet the water here long has been eyed with distrust and disdain by residents who fear heavy metal or chemical contamination — or just don’t like it.

Marie Vega, who lives in North Philadelphia, prefers to spend $100 a month on bottled water rather than serve tap to her four kids. She says it makes her feel ill.

“It tastes nasty,” said Vega, who set up a taste test on her front step to make her point to Inquirer journalists.

“I think we understand why [so many residents] aren’t drinking it,” said Nina Hoe Gallagher, director of Research & Evaluation, ImpactED at the University of Pennsylvania. “And a lot of the reasons are just a lack of trust.”

But when it comes to water — essential to life — perception has profound implications, especially given what often underlies residents’ concerns. A few examples:

At a recent event at City Hall, a Water Department worker in a superhero cape extolled the virtues of tap to startled passers-by, some of whom expressed surprise that they liked the water samples they tried.

Penn’s Hoe Gallagher is working with the Water Department, the advocacy group PennEnvironment, and the Water Center, also at Penn, on a project designed to persuade residents to drink tap. With funds from the William Penn Foundation, the group has hired water ambassadors — residents of the neighborhoods that eye their taps most skeptically — to spread the word in the Drink Philly Tap campaign.

But the Water Department is doing more than public relations to stamp out rumors and address issues that fuel real fears. It organizes stream cleanups to clear out unsightly trash, not the usual purview of a Water Department. It meets with other regional water companies to help ensure the quality of a river that starts 300 miles from Philadelphia.

At the heart of its mission: an enormous operation of three water treatment facilities with 2,000 employees, including scientists, technicians, and other workers charged with taking water from the Delaware and Schuylkill, and making it drinkable — and, to some customers, even tasty.

»PERCEPTION: How do Philadelphians feel about their water? Everything from ‘nasty’ to not bad.

Though far larger and more sophisticated, the elements of the process are similar to what began in the United States in 1914 with the advent of chlorination. The biggest difference: The river is much cleaner, meaning it requires less cleanup, fewer treatment chemicals, and probably tastes better. But industrial chemicals and other pollutants still make their way into the water and must be kept below federal standards established after the Clean Water Act of 1972.

The Water Department has to comply with National Primary Drinking Water Regulations for more than 90 contaminants. It also has to follow secondary standards for 15 contaminants that aren’t enforced but that have suggested levels. There is also a separate Lead and Copper rule.

The Environmental Working Group (EWG), a nonprofit that monitors water quality, said the latest data from 2018 found that Philly’s tap water was in compliance with all federal health-based drinking-water standards, including lead. But it said 10 chemicals exceeded EWG’s own recommended guidelines composed from a suite of sources and based on 2015 data, the latest the group had analyzed.

For example, Philadelphia reported a higher level of Atrazine, an herbicide usually found in agricultural runoff, in its water than EWG recommendations. But the level was within legal limits. The herbicide is a hormone disruptor that can harm male and female reproductive systems. The other compounds exceeding EWG’s recommendations were linked to cancer and thyroid issues.

Maurice Sampson, eastern Pennsylvania director for the nonprofit Clean Water Action, sometimes lobs criticism at government officials but gives the Philadelphia Water Department good marks.

“We think that Philadelphia drinking-water quality is high,” said Sampson, who lives in Mount Airy. “We have a full science lab that tests the water quality. Your smaller municipalities don’t have that.”

But he acknowledges the “Schuylkill punch tinge” — a flavor even some committed tap-water drinkers may describe as heavily chlorinated — can turn people off.

That kind of talk draws a wince from Abey John, a chemical engineer with degrees from Johns Hopkins and Villanova Universities, who manages the Baxter treatment plant complex, set adjacent to the greenery of Pleasant Hill Park. He, along with his counterparts at the Queen Lane and Belmont plants on the Schuylkill, is charged with making sure the water that leaves their plants is clean and clear.

River water gets to your faucet in a long journey that includes filters, doses of chlorine, and other chemicals. It gets tested, tasted, and sniffed.

On a tour of the plant, John points to the riverbank, where water from the Delaware comes in looking murky — what the experts call highly turbid. Turbidity is just one measure of water quality. Federal rules say drinking water has to be less than 1 nephelometric turbidity unit, known as NTU. The Schuylkill water often clocks in at 30 NTUs because it is fast flowing and picks up more sediments than the Delaware, which often runs about 10 NTUs. The Baxter plant usually reduces it to below 0.3, which is pretty clear.

Standing on the roof of the plant, John explains that turbidity gets reduced dramatically through multiple processes that also kill off bacteria and pathogens that could make people sick. The raw river water passes through an initial screen that keeps out fish and other aquatic life. It settles in a lagoon where big pieces of wood and leaves sink to the bottom. From there, it is pumped to a treatment building and dosed with chlorine. Further treatment in giant outdoor tanks culls out remaining solids in a process known as flocculation.

»THE SOURCE: What’s in your Philly drinking water? Maybe not as much as you fear.

Transferred into a building the size of several suburban Walmarts, water is run through three-layered filters: The first is anthracite coal from Pennsylvania’s mountains, then sand, then gravel. The filters are flushed and backwashed several times a day to keep them clean.

Throughout the process, scientists upstairs in the Baxter lab check the chemical composition of the water every three hours to ensure it is clean, safe — and hasn’t had too many treatment chemicals added — before it is sent out to 750,000 customers in Northeast Philadelphia and Lower Bucks County.

About six miles away, Gary Burlingame, director of the Water Department’s Bureau of Laboratory Services sits in an office decorated with an old chart showing the number of Philadelphians who died from typhoid fever, mostly in the 19th century, but even a bit into the 20th century. Deaths plummeted after the city began dosing its water with chlorine, the naturally occurring element first used as a disinfectant 200 years ago in France.

The chart is a constant reminder to Burlingame of the important work at his lab, where "nothing gets to be a level where it’s a big concern.”

The lab leads several in a system that employs 116 chemists, biologists, and engineers focused on drinking-water quality. As science learns more about what can go wrong with water, the testing has grown more sophisticated. Just one piece of testing equipment, a liquid chromatograph in the organics lab, costs $250,000.

“We’re trying to start from a positive conversation,” Burlingame says.

Burlingame, a Drexel graduate, boasts that the Water Department is now one of the biggest users of Drexel interns. They test the water for E. coli, cryptosporidium, alkalinity, and mineral content. Scientists look for pharmaceuticals that might be in the water from people who flush them down toilets.

They look for metals (such as lead), fertilizer, sodium, and even caffeine content.

“These are way below any harmful levels,” Burlingame says.

Ralph Rogers, a project manager, has built a water-quality monitoring system that provides real-time data from 40 stations around the city. The stations are equipped with sensors that pick up and relay the information to the lab. Rogers can look at an array of gauges he’s installed in what looks like a large metal cabinet filled with water lines, digital readouts, and a computer.

The lab also tests iron water mains, some of which can be 100 years old, for corrosion. One to two fail on average each week and can cause brown water at a home.

Proud as he is of his agency’s science, Burlingame has seen his duties expand beyond the lab in response to his water’s image problem. He doesn’t just run the lab, he gets the word out by talking to customers, through books he’s written, newsletters, and industry articles. The water is examined often, he said, and tests are run “thousands of times a month.”

Burlingame says a strength of Philly water is in its “ingredients": a mix of minerals beneficial to bread- and beer-making.

In the end, Burlingame, who also lives in the city and drinks the water, says the lab has one real goal: “We want to help our customers.”

Leon Sanford, 28, a North Philadelphia resident and prep cook, is one of the department’s new water ambassadors who all receive training from the Water Department and Hoe Gallagher’s group so they can explain why the water is good to drink. Sanford has personal experience to add to that, since he grew up drinking Philly tap water.

Friends, he said, ask him all the time if it’s really safe.

He keeps it simple: "I say: ‘Yes, it’s safe.’ ”

Editor’s Note: “From the Source: Stories of the Delaware River” is produced with support from the National Geographic Society, the Lenfest Institute for Journalism, and the William Penn Foundation. Editorial content is created independently of the project’s donors.

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