Repiping and Water Line Replacement in Baltimore, MD

When does a Baltimore home need repiping instead of another repair?

Repiping makes sense when the supply pipe itself is worn out, not just one joint or fitting. HUD’s 1999 Rehab Guide names lead piping, failed polybutylene joints or pipes, low water pressure and corroded or broken pipes among the reasons a home’s water distribution system gets repaired, modified or replaced.

• Galvanized steel: HUD’s 2000 inspection guideline puts its service life at 20 to 50 years and calls rusted fittings and rust-colored water, particularly from hot water lines, signs of advanced deterioration. It says low flow and low pressure are likely caused by pipe clogged with rust and mineral deposits.
• Pinhole leaks: Texas A&M AgriLife Extension’s 2012 corrosion fact sheet says corrosion thins metal pipe until pin-size or larger holes leak into floors, walls or ceilings.
• Polybutylene: HUD’s 1999 Rehab Guide says polybutylene fittings used in the 1970s and ’80s “failed in many homes with disastrous results.” A 1995 national class settlement funded replacement of eligible leaking systems, according to a 2003 federal appeals court opinion.
• Mixed metals: HUD warns that galvanized steel joined to copper or brass corrodes where the two metals meet unless a dielectric coupling separates them.
• Lead: EPA says lead particles can attach to the surface of galvanized pipe and later enter drinking water, and that solder made or installed before 1986 contained high lead levels.

About 42% of homes in the Baltimore City ZIP codes we serve were built before 1940, according to U.S. Census Bureau American Community Survey estimates. HUD notes copper came into widespread use in most of the country in the 1930s, and any original galvanized pipe still in a house that old has outlasted HUD’s 20-to-50-year range.

A pipe that is leaking today needs a repair before any replacement is planned; the emergency repair for each kind of old pipe is laid out material by material on our pipe repair page.

How to plan a repipe: timing, pipe routes and electrical grounding

The easiest time to repipe is when walls and ceilings are already open. HUD’s 2000 rehabilitation inspection guideline advises considering replacement of any galvanized steel pipe exposed during rehab work, and HUD’s 1999 Rehab Guide warns that water pipes have historically grounded electrical systems, a safety function that has to be restored afterward.

• Pipe routes: Baltimore City’s plumbing code requires water pipe in exterior walls, attics and other spaces exposed to outdoor temperatures to be protected from freezing, and in heated spaces the pipe must run on the heated side of the insulation.
• Grounding: under the plumbing code Baltimore City adopts, a metal water service pipe used for electrical grounding cannot be replaced with plastic until another approved means of grounding is in place.
• Partial jobs: where new copper meets galvanized pipe that stays, HUD’s guideline calls for a dielectric coupling between the two metals.
• PEX runs: HUD’s 2006 PEX design guide says PEX suits remodeling as well as new construction, and pulling several flexible lines at once through shared holes in joists cuts installation time.

Replacing the water service line: which part do you own?

In Baltimore City, DPW maintains the outdoor water line up to and including the meter, and the property owner is responsible for the line from the meter into the house. DPW’s Water Main FAQ adds that the customer pays all costs to maintain the service pipe on their property, so replacing that stretch is the owner’s project.

Baltimore City DPW and Baltimore County’s Department of Public Works and Transportation both state that part of each residential service line on the Baltimore Metropolitan Water System, which the City owns and runs for City and County customers, is privately owned.

• Depth: Baltimore City’s plumbing code requires water service pipe below the recorded frost line, with at least 36 inches of earth cover.
• Shared trench: Baltimore County’s code requires a water service pipe laid in the same trench as the building sewer to sit at least 12 inches above it and 12 inches to the side.
• Shut-off valves: Baltimore County’s code requires an underground shut-off valve near the public connection and an indoor valve within 3 to 5 feet of where the water service enters the building.

If the reason for replacement is a hidden leak, testing for a leak between the meter and your foundation shows how to confirm which side of the meter it is on and how to request a bill credit once it is repaired.

Is there help paying to replace a service line or repipe in Baltimore?

Help depends on the pipe and on which side of the city line the house sits. Baltimore City DPW says customers pay to maintain the service pipe on their own property, while Baltimore County says eligible residents can have required service line replacement done free, the Baltimore Sun reported in August 2026. Income-based home repair loans cover plumbing in both.

• Baltimore City DHCD offers home repair loans, some of which may be forgiven or deferred, to eligible owner-occupants for repairs including plumbing. Its page, updated in August 2026, lists income limits of $74,800 for one person and $106,800 for a household of four; applications go through the LIGHT Intake & Assessment Unit at (410) 396-3023.
• Baltimore County’s housing rehabilitation loans, as described on the County’s housing page in September 2025, cover major systems including plumbing for households at or below 80% of area median income. The work must be done by a licensed, insured contractor, and the State-funded MHRP loan carries 0% to 6% interest over 20 years.
• Baltimore County lead line questions go to DPWT’s Lead Reduction Program at 410-887-1368. An earlier County offer of free customer-side lead line replacement required reporting the line through the self-reporting survey by March 31, 2026, a deadline that has passed.
• EPA’s Lead and Copper Rule Improvements require water systems to fully replace lead and galvanized-requiring-replacement service lines under their control within 10 years of the November 1, 2027 compliance date. A utility that charges owners for the private portion must explain in its plan how it will help customers who cannot pay.

What a City or County service line notice means, and how to check the pipe with a key and a magnet, is covered in how to read a Baltimore service line material notice.