Plumber InMount Holly

Sewer backup: what the city checks and what you own

The city maintains about 250 miles of public water and sewer line, 14 lift stations and 2,600 manholes, and it runs a 24-hour on-call line. Its guidance is direct: if your sewer clogs or backs up, call its service center first, because the problem may not be in your line. If the main is blocked, a jet truck clears it.

If the main is flowing, the blockage is on your side. Start with drain cleaning to restore flow, then a sewer camera inspection if it has happened before. Grease is a frequent cause. The city attributes 50 to 75 percent of sanitary sewer overflows to fats, oils and grease, and the same buildup happens in kitchen lines and laterals. For restaurant and multi-unit lines, hydro jetting removes it from the pipe wall.

An 1875 mill town with a newer half

The town took its name from the Mount Holly Cotton Mill, started in 1875 and now the oldest surviving mill in Gaston County. The Woodlawn Mill followed in 1906. About one home in five was built before 1960, and the oldest are plumbed with cast iron, galvanized steel and clay unless someone has replaced it.

About half of the housing has gone up since 2000, according to Census Bureau estimates, in subdivisions such as Dutchmans Ridge and Imagery on Mountain Island. Those homes have PVC drains and PEX or CPVC supply lines. Their first big plumbing expense is usually the water heater, followed by small leaks at valves and fittings that leak detection can trace before they stain a ceiling.

Mount Holly's backflow ordinance, adopted in 2022

Every backflow assembly on the city's water system must be tested and inspected at least once a year by a certified tester on the city's approved list. The tester has 10 business days to submit the report. After that the test does not count and has to be repeated. If the test shows a repair is needed, the work must be done within ten days.

Three details catch owners out. Irrigation systems are classed as high hazard and need a reduced pressure assembly. Atmospheric vacuum breakers are not permitted on service connections at all. Above-ground assemblies must sit inside an insulated freeze-protection enclosure. Alpha Drain's backflow testing is $199 per assembly, and we do backflow repair. Confirm your tester is on the city's list before the visit.

• Annual test by a city-approved certified tester
• Report due within 10 business days
• Repairs completed within 10 days
• Records kept for 5 years
• No atmospheric vacuum breakers

Water pressure, the 30 psi rule and private plumbing

City water comes from Mountain Island Lake and is treated at a plant built in 1983. The city is required to deliver at least 30 pounds per square inch at your meter under normal conditions, and it will test the pressure there if you report a problem.

If the meter reads 30 psi or more, the city's part is done and the cause is in your plumbing. In older houses that is usually galvanized pipe closed up with rust. In newer ones it is more often a failed pressure regulator, a clogged fixture screen or a hidden leak. We sort that out with a pressure test at the house and leak detection, then the plumbing repair itself. Repair labor is covered by a 1-year warranty.

Mount Holly neighborhoods we serve

Downtown Mount Holly Historic District, Woodlawn, Catawba Heights, Dutchmans Ridge, Dutchmans Meadow, Stonewater, Imagery on Mountain Island, Kendrick Farm, Riverfront, Madora, Autumn Woods, Fites Creek Plantation, Westland Farm, Mountain Island Village, and the streets in between.

Mount Holly ZIP codes we serve: 28120.