Philadelphia, PA
Backflow testing in Philadelphia
Updated · Editorial team; not yet technically reviewed
Short answer
The Philadelphia Water Department requires backflow prevention assemblies to be tested at installation, after every repair, and annually, by a City-certified backflow technician. Results go to PWD's Industrial Waste and Backflow Compliance unit within 48 hours, on the Backflow Prevention Assembly Test and Maintenance Record (Form 79-770).
What's different in Philadelphia
Annual testing and routine maintenance of each containment assembly by a City-certified backflow prevention technician is required. [1]
Tests must be done immediately on installation, immediately after each repair and annually after that, with results sent within 48 hours. [2]
Test reports use the Backflow Prevention Assembly Test and Maintenance Record (Form 79-770) and go to PWD's Industrial Waste and Backflow Compliance Unit. [2]
When a test is due
| Event | Test |
|---|---|
| New assembly installed | Immediately |
| Assembly repaired | Immediately after |
| Every year | Annual test |
| Any test | Report within 48 hours |
Which homes have one
Rowhouses with lawn irrigation, boilers with chemical treatment, or a fire sprinkler connection are the usual residential cases. See backflow testing and Philadelphia frozen pipes, since outdoor assemblies need winter protection.
Common questions
Does PWD count a repair as a reason to retest?
Yes, an assembly must be tested immediately after each repair, on top of the annual test.
Who can test backflow in Philadelphia?
A City-certified backflow prevention technician.
How fast must Philadelphia test results be filed?
Within 48 hours of completing the test.
What form records a Philadelphia backflow test?
Form 79-770, the Backflow Prevention Assembly Test and Maintenance Record.
Where do Philadelphia backflow reports go?
To PWD's Industrial Waste and Backflow Compliance Unit.
Is a test needed after repairing a Philadelphia assembly?
Yes, immediately after each repair.
Do Philadelphia homes need backflow devices?
Homes with irrigation, treated boilers or sprinkler connections commonly do.
Does PWD require routine maintenance too?
Yes, annual testing and routine maintenance are both required.
Do outdoor backflow assemblies freeze in Philadelphia?
They can; insulate or drain them for winter.
Is a new Philadelphia assembly tested right away?
Yes, immediately upon installation.
More plumbing help in Philadelphia
- Water Line Repair in PhiladelphiaPhiladelphia lead service lines: owner responsibility, free replacement during main work, the free ZIP-code pilot, and 0% HELP loans.
- Sewer Line Repair in PhiladelphiaPhiladelphia sewer and water line repair: PWD's HELP loan covers repairs at 0% interest over 60 months after a Notice of Defect.
- Basement flooding in PhiladelphiaWhy Philadelphia basements back up and how PWD's Basement Backup Protection Program installs free backwater valves and downspout changes for eligible homes.
- Leak Detection in PhiladelphiaIn Philadelphia, the owner is responsible for water piping from the city main, including the ferrule and curb stop. How leaks are found, and PWD's Notice of Defect.
- Frozen Pipe Repair in PhiladelphiaFrozen pipes in Philadelphia: keep the meter area above 40°F, trickle a faucet, shut off outdoor lines, check neighbors first.
- Drain backing up in PhiladelphiaWhy Philadelphia drains back up: grease hardens in the lateral connecting homes to the sewer, sewage backs into houses, and how PWD says to dispose of it.
- Backflow Testing: the full guideWhat backflow is, which homes and businesses need backflow preventers, how annual backflow testing works, and what happens if a device fails.
- Plumbing in PhiladelphiaLocal water, housing and climate conditions, and the calls Philadelphia homes need most.
How other cities handle it
- Backflow testing in AustinAustin Water's backflow testing rules: who may test, the 5-day report deadline, online filing, and the irrigation rebates that pair with an upgrade.
- Backflow testing in San AntonioSAWS backflow testing rules for San Antonio: the June 30 annual deadline, the codes behind it, reminder notices, and what a 10-day notice means.
- Backflow testing in DenverDenver Water's backflow rules: annual testing, the May–September irrigation testing season, required device types, 30-day reminders, and where results go.
- Backflow testing in SeattleSeattle Public Utilities backflow testing rules: annual tests by your anniversary date, Washington-certified testers, reporting, and non-compliance charges.
- Backflow testing in PortlandPortland Water Bureau backflow rules: yearly testing by a state-certified tester, the spring timing it prefers, reminder letters with labels, and shutoff risk.
- Backflow testing in CharlotteCharlotte Water backflow rules: residential irrigation tested every 3 years, residential domestic yearly, approved testers, and RP assemblies on irrigation.
- Backflow testing in RaleighRaleigh Public Utilities backflow rules: residential irrigation tested by July 1 every three years, commercial yearly, owner-paid certified testing, and contacts.
- Backflow testing in TampaCity of Tampa Water Department backflow rules: residential tests every two years, commercial yearly, certified technicians, and the 7-day online reporting rule.
- Backflow testing in Salt Lake CitySalt Lake City Public Utilities backflow rules: tests within 10 days of installation and yearly after, which homes need protection, and secondary water.
- Backflow testing in Colorado SpringsColorado Springs Utilities backflow rules: who must test annually, the July 1 deadline, the $405 fine, licensed testers entering results, and single-family guidance.
- Backflow testing in Fort WorthFort Worth backflow rules: annual tests for commercial and health-hazard assemblies, a three-year cycle for low-hazard irrigation, and registered testers.
- Backflow testing for JEA customers in JacksonvilleJEA residential backflow rules: testing at least every two years by JEA Qualified Vendors, dual checks replaced every five years, and reclaimed-water irrigation.
- Backflow testing in Fort LauderdaleFort Lauderdale backflow rules: residential irrigation tested every two years, commercial yearly, only PVB or RP devices on irrigation meters, and certified testers.
- Backflow testing in DallasDallas backflow rules: lawn irrigation assemblies don't need annual tests, only when new, repaired or replaced; high-hazard assemblies need annual registered tests.
- Backflow testing in HoustonHouston backflow testing: testing companies must register with the city, testers need TCEQ licenses, and gauges need annual calibration reports filed with Houston.
- Backflow testing in PhoenixPhoenix backflow rules: assemblies tested at least yearly, 60 days to test after the reminder letter, then a 72-hour disconnection notice. Who needs one at home.
Sources (2)
- Philadelphia Water Department, Cross-connection control FAQ · checked 2026-10-03
- Philadelphia Water Department, Cross-connection control manual · checked 2026-10-03