The average water main in Philadelphia is 76 years old, and January sees an average of more than 175 breaks

Facts and figures about the city’s aging water supply system.

The former Fairmount Water Works in 2020, with the Schuylkill at flood levels

The former Fairmount Water Works in 2020, with the Schuylkill at flood levels

Mark Henninger / Imagic Digital
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Philly’s water system breaks often, with an average of 776 water mains breaking annually over the past 15 years.

January is typically the worst month, and this year things were bad: one particularly rough day brought 30 reports of potential water main breaks across the city. That was part of a three-day stretch with 111 reports of leaks in city-owned and private service lines.

Part of the problem is the age of the system, which was one of the first of its kind in the U.S.

In 2015, the average water main in the city was 78 years old. Since then, replacements have decreased the average age to 76 years old, according to Water Department spokesperson Brian Rademaekers, but the city is still behind on its goal to replace them.

Problems can come with devastating consequences for residents and businesses.

A Center City water main break in July 2018 caused around six inches of flooding and temporary power outages for 1,000 customers. The break affected dozens of businesses, and it took almost a year to reopen several blocks of Sansom Street. And last summer, a water main installed before 1900 broke in Queen Village, flooding homes and businesses at 6th and Bainbridge and causing damage to streets, sidewalks, and basements that’s still being repaired six months later.

About half of Philadelphia’s water supply comes from the Delaware, and the other half from the Schuylkill. There are tens of thousands of hydrants, and 3,100 miles of water mains, which can rack up $275,000 in repair costs annually.

Here’s a look at how it all works, along with some things you can do to help keep it running smoothly.

By the numbers

Most of the stats below are according to department spokesperson Rademaekers, who noted some are estimates.

City pipes

Once upon a time, Philadelphia was outfitted with wooden water mains, but the city started laying only cast iron pipes in 1832. According to PWD’s website, the city’s last wooden mains were taken out of service in 1858.

Whatever material they’re made from, water mains don’t last forever. They get weaker over time from internal or external corrosion, which can be caused by temperature changes, underground work, or traffic loading.

“The Water Department closely monitors water main conditions to determine that adequate capital investment is made, to predict long-term water main replacement needs and refine the criteria for replacement selection,” Rademaekers said.

On average, the department has replaced 19 miles of water mains per year over the past 25 years, and it budgeted $78 million in the 2020 fiscal year to speed up its replacement program. The COVID-19 pandemic interrupted its progress, according to Rademaekers, leading to a “significant decrease” in miles replaced in the 2021 fiscal year.

Now, the department is looking to gradually increase its goal — set at 34 miles of mains in fiscal year 2020 — by 2 miles each year until 2026.

Some more stats describing the city’s old and lengthy network:

  • 3,100 — miles of water mains managed by PWD, as of the last fiscal year
  • 75.64 years — average age of a water main in the PWD system, as of January 2022
  • 1,033 — miles of water mains checked for leaks per year, approximately
  • 3 years — time it takes the PWD leak detection program to survey the entire 3,100-mile system
  • 19 — miles of water mains replaced every year, on average (since 1997)
  • 42 — target number of miles of water mains to be replaced annually by fiscal year 2026

Breaks and repairs

Water main breaks are anything but rare in Philly, with what averages out to around two per day for the last decade and a half.

The water department says Philly isn’t alone in these problems. In 2020, the city’s number of breaks per mile of water mains fell below the national average, Rademaekers said. He credited it to the city getting an early start on replacement, with the effort beginning some 30 years ago.

How long does it take to fix a water main break? Rademaekers declined to give an average, and said it depends on the situation.

“Every water main break and repair is distinct, and repairs can take anywhere from hours to 6 months or more depending on the situation,” he said. “Even after water infrastructure is repaired, additional utility work and street repairs can add months to some repair jobs.”

Customers connected to a broken main could see “a disruption in service for upwards of 8-10 hours while repairs are being made,” Rademaekers said. But the department tries to cut down on disruptions “by isolating the break to the smallest area allowable,” he added.

Usually, customers don’t need to be directly notified when there’s a break, Rademaekers said, but the department does conduct outreach if the circumstances — like loss of water, for example — call for it, or if there’s water in basements.

More on breakages throughout the city:

  • 776 — average number of water main breaks each year, over the last 15 years
  • 179 — average number of water main breaks every January, the busiest month of the year for breaks, since 1965
  • 34 — average number of water main breaks every September, the slowest month of the year for water main breaks, since 1965
  • 30 minutes — amount of time you should flush your home plumbing to clear debris after water main work that affects your home
  • $274,001 — cost of water main breaks in 2021 (includes costs related to non-2021 losses)
  • $18,488 — total claim settlements paid in 2021(for claims occurring in 2021)
  • $4,327 — average claim settlement paid in 2021

Note: the cost figures come from the Office of Director of Finance Risk Management Claims Unit, and they don’t include any claims or litigation being managed by the City of Philadelphia Law Department.

People and safety

The water department has a 130-square-mile service area, providing water to people throughout Philly and beyond.

Some numbers on the people who use and run Philly’s water system:

  • 490,000 — number of active Philadelphia Water department customer accounts
  • 1.6 million — estimated number of people served by PWD (as of 2020)
  • 1 — number of wholesale water service contracts (it’s with Aqua PA)
  • 10 — number of wastewater contracts with with neighboring municipalities, corporations, and other entities outside the city
  • 2,100 — number of PWD employees, as of the fiscal year ending June 30, 2021
  • 25,000 — number of fire hydrants maintained by the department, as of fiscal year 2021

Intake and treatment

The water department doesn’t just manage water mains — it also manages the city’s combined storm and sanitary sewer system, along with stormwater inlets.

Drinking water is treated at three different plants: the Samuel S. Baxter plant on the Delaware, and the Belmont and Queen Lane plants on the Schuylkill. The department also runs three water pollution control plants — one in the Northeast, one near the airport, and one in the warehouse complex by the river in South Philly.

Some interesting figures about your water’s sourcing and treatment, as of the most recent year available (2020 or 2021):

  • 3,700 — miles of sewers managed by PWD
  • 71,500 — number of stormwater inlets managed by PWD
  • 78.24 billion — gallons of water treated at Philadelphia’s drinking water treatment plants
  • 153 billion — gallons of wastewater and stormwater treated at PWD’s three water pollution control plants
  • 58% — amount of the water supply sourced from the Delaware River
  • 42% — amount of the water supply sourced from the Schuylkill River

What to do if you suspect a main break

Report it

The Water Department can detect some large water main breaks remotely, but PWD relies mostly on customers to report water emergencies, so the department can investigate situations and make any necessary repairs.

“Until a leak or possible break is called in, there is a good chance we won’t know about it,” Rademaekers said.

Emergencies you should notify PWD about include main breaks, taste and odor problems, open hydrants, neighborhood flooding, and water in your basement, according to the PWD website.

The number to report a water emergency is 215-685-6300, and it’s available 24/7.

But first, check with your neighbors

If water isn’t coming out of your faucets or if the pressure seems low, a good first step is to ask neighbors if they’re experiencing similar problems, per Rademaekers.

“If the whole block is impacted, it’s probably a main break that should be called in right away,” Rademaekers said. “However, if only you are having an issue, it is likely a plumbing problem on your property, such as frozen pipes, and you should contact a plumber or use our cold weather tips to troubleshoot the problem.”

You can find the Water Department’s tips on cold weather and how to handle frozen pipes here.

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