Arlington County lists its tap water at 8 grains per gallon (142 mg/L), which is moderately hard: enough to build scale in water heaters and on glass, though not extreme. A softener sized to that number and your household can cut that buildup. Call the number on this page to be connected with a local plumber in Arlington.

Signs hard water is costing you
- A gritty white film on shower doors that comes back days after cleaning
- Showerheads with clogged nozzles that spray at odd angles
- Rumbling or popping inside the water heater as it fires
- Dishes and glassware that look cloudy straight out of the dishwasher
- Soap and shampoo that never seem to lather fully
- An existing softener that keeps running out of capacity or leaks at the control valve
What Arlington water means for a softener
The County's Water, Sewer, Streets Bureau delivers Potomac River water treated by the Washington Aqueduct at the Dalecarlia plant, and a small pressure zone in the Willston area receives water bought from Fairfax Water. The County reports hardness of 8 grains per gallon. That figure is the starting point for programming a unit: a plumber multiplies it by the household's daily water use to pick a resin size that regenerates every several days instead of every night.
Arlington disinfects with chloramine for most of the year and switches to chlorine for about six weeks each spring while it flushes mains. A softener only exchanges calcium and magnesium; it won't remove disinfectant taste. If taste bothers you, a carbon stage rated for chloramine, or a drinking water filter at the kitchen sink, is the add-on to ask about.
The median home in the county dates to about 1976. In older houses and many condos, the main shutoff and water heater often share a cramped utility closet, so finding room for a resin tank, a brine tank and a drain for the discharge line is part of the job.
What affects the cost
- Resin capacity, set by hardness and how many people live in the home
- Whether the main line can be cut and looped near the water heater or needs a longer reroute
- Distance to a floor drain or standpipe for the regeneration discharge
- Building rules in condos and co-ops about shutting water off
- Add-ons such as a carbon filter or a reverse osmosis faucet
- Hauling away an old unit
What happens when you call
The number on this page is a free referral line, not a plumbing company. It connects you with an independent plumber who works in Arlington. Mention the size of the household, where the main shutoff and water heater are, and whether a softener is already in place. If the work involves new piping, the plumber can sort out whether a permit is needed through Arlington County's building permits and inspections program.
Water Softeners & Filtration questions in Arlington
How hard is the tap water at my address?
Does chloramine in city water wear out softener resin?
Will softened water add sodium to what we drink?
Will a softener help my water heater or tankless unit last?
More plumbing services in Arlington
Water Softeners & Filtration nearby
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