North Charleston buys soft 54 to 56 mg/L water from Charleston Water System, and its freight and retail corridors coat glass with diesel and brake dust.
North Charleston buys the same soft water as Charleston, so it will not mark a pane as it dries; diesel and brake dust from the freight and retail corridors are what coat the glass. Wash from March to May or in October and November, before and after the steamy summer. Modest, uniform postwar housing makes this the most price-competitive market in the Lowcountry, with a single-story exterior at $240 to $430.
The supply reaching North Charleston is the same soft Charleston Water System product its neighbour drinks, in the region of 55 mg/L, and it will not mark a pane as it dries. That removes the entire mineral question from the job here. What it leaves behind is a purely mechanical problem: the residue on this city's glass is greasy and particulate rather than crystalline, which means detergent and dwell time matter and rinse purity does not.
| Hardness | 54–56 mg/L as CaCO₃ 3.15 to 3.27 grains per gallon, as published by the supplying utility. |
|---|---|
| pH | 8.7 (range 8.6–8.8) |
| Alkalinity | 30 mg/L as CaCO₃ (range 26–35) |
| Iron | 0.11 mg/L (range 0.1–0.15) |
| Manganese | 0.06 mg/L (range 0.05–0.13) |
| Sodium | 8 mg/L (range 5–12) |
| Chloride | 14 mg/L (range 11–17) |
| Total dissolved solids | 101 mg/L (range 76–140) |
| Disinfectant | chloramine |
| Source and treatment | Purchased finished water from Charleston Water System, drawn from Bushy Park Reservoir (primary) and the Edisto River (secondary) and treated at the Hanahan Water Treatment Plant · North Charleston treats no water of its own. Upstream: rapid mix with alum, powdered activated carbon, lime and polymer, coagulation and flocculation, sedimentation in plate settlers, filtration, then clearwell dosing of chlorine dioxide, chloramine, fluoride, orthophosphate and lime. · No softening step. |
Not in the report: corrosion index.
SOURCE · Charleston Water System, Water Quality Results (Monthly Averages) 2024, YTD average/min/max (charlestonwater.com), read with the treatment-process diagram in the 2026 Water Quality Report. North Charleston operates no treatment of its own and is inside Charleston Water System's retail area. · How we source these numbers
Traffic and industry run on a weekday rhythm rather than a seasonal one, so commercial frontage along the freight corridors dirties steadily and predictably regardless of month. Salt matters only close to the rivers and fades inland. Pollen is a spring event in the older tree-lined districts. Humid summer weather slows every dry-down and lengthens the working time needed per pane, which is a scheduling consideration rather than a chemistry one.
SOUTH CAROLINA SEASON BY SEASON →North Charleston buys its water rather than making it: Charleston Water System's own service description names the city directly, so the hardness figure is the supplier's — 54 to 56 mg/L, or 3.15 to 3.27 grains per gallon, which is soft. Nothing here needs treated rinse water. The same wholesale network reaches Mt. Pleasant, Dorchester County, Kiawah and Seabrook, Folly Beach, Sullivan's Island, Isle of Palms and Joint Base Charleston, so a great deal of Lowcountry water originates at the same plants regardless of whose name is on the bill. Where this city differs from its neighbour is in what the air delivers. It sits inland along the rivers rather than in open tidal water, so salt falls away toward the north, and in its place comes a working port and freight economy that puts road grime, diesel particulate and brake dust on commercial glazing at levels the historic peninsula never reaches.
North Charleston does not run its own treatment. Its retail supply comes from Charleston Water System, whose own service description names North Charleston directly alongside Charleston, Hanahan, Ladson, James Island, Daniel Island and West Ashley.
That means the hardness figure here belongs to the supplier rather than to the city, and it is the same one: 54 to 56 mg/L, which the utility prints as 3.15 to 3.27 grains per gallon. Soft water, reaching both cities from the same plants.
The wholesale arrangement reaches further than the city boundary in every direction. Charleston Water System also sells to Mt. Pleasant Waterworks, Dorchester County Public Works, St. Johns Water Company serving Kiawah and Seabrook, Folly Beach, Sullivan's Island, Isle of Palms, Joint Base Charleston and Lincolnville — so even where another provider's name appears on a bill in this area, the water frequently originated here.
For glass that settles the question cleanly: no part of North Charleston needs treated rinse water, and any spotting that appears on a pane arrived from the air rather than through the meter.
What sets this city apart from its neighbour is distance from the water and what replaced it. North Charleston runs inland along the Ashley and Cooper rivers rather than sitting in open tidal water, so salt loading falls off markedly toward the northern subdivisions.
In its place sits an industrial and logistics economy. This is a port and freight city with a working container terminal, rail, and the state's heaviest concentration of distribution and manufacturing floor space, and that produces road grime, diesel particulate and brake dust on ground-floor commercial glazing in quantities the historic peninsula never sees.
The former naval complex is the single largest glazing question in the city. Decommissioned industrial buildings carry original steel-framed factory sash in enormous runs, and the redevelopment work happening around them mixes newly sealed units with century-old industrial glazing on the same site.
This is the most price-competitive market in the Lowcountry, because the housing stock is modest and uniform and route density in the postwar subdivisions is excellent. Commercial and industrial frontage is where margin lives, and it prices on access and soiling rate rather than on glass area. Historic-district premiums do not apply here the way they do across the Ashley, which keeps residential quoting lean.
Inland residential stock is single-storey, accessible and undemanding, and with soft water a homeowner has every advantage. The exception is anything greasy: diesel and brake residue on glass near the freight corridors will smear under a water-only pass and needs a detergent step rather than more effort. Factory sash on the former naval complex is industrial-scale work requiring equipment and site permissions that put it firmly outside the domestic market.
OPEN COST ESTIMATOR →2025 annual mean at the North Charleston Fire Station monitor, 2800 Carner Avenue (NCFS), 12.2 km south-east of the city (EPA site 45-019-0020).
Largest air release: Ingevity South Carolina LLC Charleston Chemical Plant, 5598 Virginia AVE (chemicals), inside the city limits, 66,672 lb in 2024.
Charleston Water System lets a business that uses water at changing locations draw from its hydrants only under an annual transient water use permit, with an inspected air gap on each tank and a decal on the vehicle. Opening or interfering with a hydrant without that permission is a misdemeanor under state law, punishable by up to sixty days in jail or a fine.
Charleston Water System, Temporary Fire Hydrant Water Use Manual (EC-CC-00029, October 2024): transient water use · checked September 2026
North Charleston's Stormwater Management Ordinance makes it unlawful to throw, drain or otherwise discharge into the city's storm system anything other than stormwater or unpolluted water the Public Works Department approves. Its exemptions cover things like lawn watering and street wash water, not detergent runoff, so a crew should catch soapy rinse water before it reaches an inlet or gutter.
City of North Charleston Stormwater Management Ordinance Sec. 4.1, printed as Appendix D of the city's January 2026 SWMP · checked September 2026
Inside the Olde North Charleston local historic district, the planning director (or a designee) reviews construction, renovation and repair in advance. Exempt: upkeep and repairs that leave the building looking the same, work not visible from a public right-of-way, and window screens and grilles (front-porch screens excepted). A like-for-like pane swap is maintenance; new window units are not.
North Charleston Zoning Ordinance Section 10-15: historic district regulations · checked September 2026
Three to four week yellow film deposition on horizontal and east-facing vertical glass. Wet-only handling. Do not scrape. Heaviest pollen-deposition state in the country alongside Georgia and Alabama.
Pure marine aerosol on ocean-side. Lifts predictably with extended alkaline-soap dwell plus citric finish. Monthly visit frequency standard on high-end coastal residential.
Not a contaminant but a conservation consideration. Original crown-and-cylinder glass survival rates 40-60% on better-preserved blocks. Conservative protocol — no scraping, water-fed pole or hand-detail only, test inconspicuous areas first.
North Charleston runs on Charleston Water System lake or reservoir surface water at a published 54–56 mg/L (CaCO₃) — 3.15 to 3.27 grains per gallon, as published by the supplying utility. The supply reaching North Charleston is the same soft Charleston Water System product its neighbour drinks, in the region of 55 mg/L, and it will not mark a pane as it dries.
Residential window cleaning in North Charleston typically runs $8–13 per pane or $240–430 for a standard single-story exterior. This is the most price-competitive market in the Lowcountry, because the housing stock is modest and uniform and route density in the postwar subdivisions is excellent.
North Charleston's drier, frost-free months are March to May and October and November, by NOAA's 1991–2020 normals for the Charleston International Airport station, where July brings the most rain. The calendar on this page marks April (after the March 1 bloom), October (after smoke season) and November (before frost). Frost nights usually run from November 27 to March 7.
Yes, if the rinse is squeegeed off before it dries: Charleston Water System publishes dissolved solids of 101 mg/L, between this site's two dissolved-solids flags. Its manganese, up to 0.06 mg/L, is at the staining level, and acid cleaners will not lift that film. It draws on purchased finished water from Charleston Water System.
In North Charleston the dominant residue patterns include soft supply at 54–56 mg/l, purchased retail from charleston water system rather than locally treated and road grime, diesel particulate and brake dust along the freight and retail corridors.
Inland residential stock is single-storey, accessible and undemanding, and with soft water a homeowner has every advantage. The exception is anything greasy: diesel and brake residue on glass near the freight corridors will smear under a water-only pass and needs a detergent step rather than more effort.
A planned garden-suburb centre from the early twentieth century with a surviving commercial ring and modest period housing around it. Walkable, low-rise and the most route-efficient district in the city. Olde North Charleston and The former Navy Yard have their own housing stock and glazing as well.
Just over the South Carolina line