Charleston, Bluffton, and Hilton Head Water Quality: A Lowcountry Pillar Guide

The four Lowcountry utilities at a glance

Lowcountry South Carolina is not one water market. It is at least four. Charleston Water System serves the City of Charleston, North Charleston, Hanahan, and most of James Island. Mount Pleasant Waterworks serves east of the Cooper. Beaufort-Jasper Water and Sewer Authority (BJWSA) covers Bluffton, Beaufort, and most of southern Beaufort County. And Hilton Head Public Service District serves much of Hilton Head Island in coordination with Broad Creek PSD and South Island PSD.

Each utility publishes an annual Consumer Confidence Report. The CCR is the authoritative source for current-year contaminant data, and we link to each one above. The rest of this guide explains what those differences mean for your tap, your appliances, and your treatment options.

Charleston Water System: Edisto River, Bushy Park, chloramine

Charleston Water System draws from the Edisto River at the Hanahan plant and from the Bushy Park Reservoir. Both are surface waters, which means seasonal swings in temperature, organic matter, and disinfection-byproduct precursors. The utility disinfects with chloramine rather than free chlorine, a choice that produces fewer regulated trihalomethanes but a more persistent residual at the tap. If you taste a swimming-pool note in Charleston water, that is chloramine.

The peninsula and West Ashley have a high concentration of pre-1950 service lines and copper plumbing. None of that affects what leaves the treatment plant. It does affect what comes out of your faucet. Our Charleston water quality article covers the historic-home plumbing angle in depth.

Mount Pleasant Waterworks: a blended system

Mount Pleasant Waterworks is the most chemically varied of the four because it actively blends water from three sources: surface water purchased from Charleston Water System, groundwater from the Middendorf aquifer, and groundwater from the Black Creek aquifer. The Middendorf and Black Creek sources are mineral-rich, which is why a softener delivers a more dramatic difference in Mount Pleasant than in downtown Charleston.

Our deep dive on the Black Creek and Middendorf aquifers explains naturally occurring fluoride and radium chemistry in those source waters and what utilities do to bring them into compliance before water leaves the plant.

BJWSA: Savannah River blended with the Floridan aquifer

BJWSA serves Bluffton, Beaufort, Port Royal, Hardeeville, and the Okatie corridor. The Chelsea and Purrysburg plants treat Savannah River surface water, and that surface water is blended with Floridan aquifer groundwater to balance hardness and dilute river-source organics. The Savannah River carries different natural organic matter than the Edisto, and that shows up in taste, in seasonal disinfection-byproduct readings, and in the PFAS data BJWSA publishes.

If you live south of the Broad River, your water is almost certainly BJWSA, and the right treatment baseline is a high-grade carbon filter (whole-house or point-of-use) plus a softener if you see scale.

For the city-specific service pages, see Bluffton filtration and Beaufort softening.

Hilton Head Island: three districts on the Floridan aquifer

Hilton Head Island is served by three public service districts in coordination: Hilton Head PSD on the north end, Broad Creek PSD in the middle, and South Island PSD on the south end. All three pull from the Upper Floridan aquifer and supplement with treated surface water purchased from BJWSA. The Floridan source is mineral-rich and very stable in temperature and chemistry. Salt-water intrusion in the shallow surficial aquifer is the long-running regional story. Our saltwater intrusion article covers the well-water side of this issue.

Hardness and scale: coastal humidity makes it worse

By national standards, Lowcountry city water is moderately soft. The CCRs typically report hardness in the 3 to 7 grains per gallon range. So why do Charleston homes see scale faster than the number suggests? Two reasons. First, coastal humidity keeps fixtures wet longer between uses, which means more time for minerals to deposit. Second, tankless water heaters and modern showerheads concentrate mineral exposure in small heated passages. Even slightly hard water can scale a tankless inlet in two seasons.

A condition-to-action table for Lowcountry homes:

PFAS and disinfection byproducts in 2026

Both Charleston Water System and BJWSA have published PFAS data in their CCRs. The 2024 EPA rule sets enforceable Maximum Contaminant Levels at 4 parts per trillion for PFOA and PFOS individually and at 10 parts per trillion for three other PFAS compounds. Utilities have until 2029 to come into compliance. Some Lowcountry source waters already test below those limits; some are close to them; reading the CCR is the only way to know for your address. Our PFAS article covers what each treatment technology actually removes, and our 2026 SC PFAS regulation update walks through the EPA timeline in plain English.

Disinfection byproducts (trihalomethanes and haloacetic acids) tend to peak in summer when warm surface water carries more organic matter into the plant. Whole-house catalytic carbon and point-of-use RO are both effective on these byproducts. The RO pillar covers the point-of-use side; the chlorine and chloramine basics article covers the whole-house side. Households on private wells should read the coastal SC well water pillar instead.

Choosing the right system for your Lowcountry home

We do free in-home water testing across the service area. The test takes about twenty minutes and produces a hardness number in grains per gallon, a chlorine residual reading, a TDS reading, and a pH. Combined with your utility's CCR data, that lets us match a system to your actual water rather than a national average. Our Lowcountry diagnostic article maps symptoms to the right system.

City-specific service pages: Charleston filtration, Charleston softening, Mount Pleasant filtration, Bluffton softening, Hilton Head filtration, Bluffton drinking water, Mount Pleasant whole-house refining, Daniel Island drinking water, James Island softening, and Folly Beach filtration.

Already know what you want and just need a quote? Reach out to schedule, or visit our about page for the short version of how we work. The reverse osmosis pillar and the coastal SC well water pillar are also useful neighbors to this guide.

Call a professional if…

• Your water has changed taste, color, or smell suddenly. A sudden change is rarely your home plumbing.
• You have a child under one year and use tap water for formula. Fluoride and sodium levels are worth confirming.
• You see scale build-up on a tankless water heater. Untreated, scale will void most tankless warranties.
• You're on a private well within the BJWSA or GSWSA service area. See our coastal well water pillar.
• You're considering a point-of-use RO for PFAS reduction. Pre- and post-filters need to be matched to actual feed water.

What to do this week

1. Pull your utility's most recent CCR using the links above. Note hardness, TTHM/HAA5, and any PFAS values.
2. Inventory your appliances. Tankless water heaters, espresso machines, ice makers, and humidifiers are the canaries for scale.
3. Schedule a free in-home water test. We bring the test kit; you get a written report.