North Myrtle Beach Water Hardness & Quality Report (2026)

North Myrtle Beach, South Carolina, in Horry County — a Horry County city adjacent to Myrtle Beach and Conway on the Grand Strand Atlantic coast — receives its municipal water from the Grand Strand Water and Sewer Authority, drawing from the Waccamaw River (Horry County) through the Grand Strand water treatment system.

The moderately hard 145.5 mg/L hardness and TDS of 373.4 mg/L (elevated TDS relative to hardness — suggesting additional mineral loading from coastal evaporitic or saline formations) reflect the east South Carolina Waccamaw River supply's moderate calcareous coastal character. The Waccamaw River drainage crosses the Carolina Coastal Plain — Cretaceous Black Creek Formation (calcareous marine clay and sand), Eocene Castle Hayne Limestone (calcareous — primary hardness contributor at the Grand Strand), and Pliocene Waccamaw Formation (calcareous marine sand). The Eocene Castle Hayne calcareous coastal limestone produces the moderately hard Grand Strand supply.

At 145.5 mg/L, North Myrtle Beach's water is moderately hard — scale builds in kettles and appliances over months, dishwashers benefit from rinse aid, and faucet aerators need periodic cleaning. Quarterly descaling is appropriate. The PFAS level of 8.0 ppt warrants a certified reverse osmosis drinking water filter — the Horry County Grand Strand coastal development corridor, the Atlantic Intracoastal Waterway PFAS background, and the Carolina Coastal Plain PFAS complex contribute to North Myrtle Beach's elevated readings.