Savannah Water Is Moderate — Here's What It Costs You Each Year

Why Is Savannah Water So Hard?

Savannah’s water comes from the Savannah River, and the short answer for why it lands at 4.1 GPG (70 ppm) is that the river doesn’t have to work very hard to pick up minerals. That puts it in the “moderate” range, which is actually on the softer side for the Southeast. But here’s the thing about the Savannah: it drains a metamorphic watershed before it hits the coastal plain, and that geology shapes everything about your water.

The river starts up in the Blue Ridge and Piedmont regions, where the bedrock is old, hard metamorphic rock like gneiss and schist. Those rocks are stingy with minerals. They’re crystalline and dense, so rainwater running over them doesn’t dissolve much calcium or magnesium. Compare that to limestone or dolomite aquifers, which are basically solid calcium and magnesium carbonate just waiting to dissolve. The Savannah simply doesn’t flow through those in any meaningful way. That’s why your water is moderate rather than rock-hard.

By the time the river reaches Savannah, it’s crossed the fall line and moved into the coastal plain. The coastal plain is lower in total dissolved solids, which is a fancy way of saying there’s just less stuff dissolved in the water. The river picks up a little more mineral content as it meanders through the sandy, clay-rich soils of the low country, but it’s nowhere near what you’d see from a limestone aquifer. So you get 4.1 GPG, which is enough to notice in the shower or on glassware, but it’s not the scale-caked nightmare some cities deal with.

One thing worth understanding: Savannah Water Resources treats the river water before it reaches your tap, and that treatment doesn’t remove hardness. The EPA doesn’t regulate hardness as a health hazard, only as an aesthetic issue under its Secondary Maximum Contaminant Level. So what comes out of your faucet is essentially what the river carried in, mineral-wise. The moderate hardness you feel is the river’s natural character, not something the utility added or removed.

How Savannah Compares to Nearby Cities

If you’ve lived in other parts of the Southeast, you know water hardness varies wildly from town to town. Savannah sits at 4.1 GPG, which is moderate. That’s noticeably softer than the national average of about 7.3 GPG, and it’s well below the 7 GPG threshold the USGS uses to classify water as “hard.” You’re not imagining it if your Savannah water feels easier on your skin than water you’ve used elsewhere.

Head south to Jacksonville, Florida, and you’re dealing with a completely different story. Jacksonville draws from the Floridan Aquifer, one of the most productive limestone aquifers in the world. That limestone is essentially fossilized shell and calcium carbonate, so the water comes out of the ground already loaded with hardness minerals. Jacksonville water runs significantly harder than Savannah’s, and anyone who’s moved between the two cities notices it immediately in soap lather and spotty dishes.

Augusta is the interesting comparison because it sits on the same river, just upstream. Augusta draws from the Savannah River too, but at a point where the water hasn’t traveled as far through the coastal plain. The geology is similar, so Augusta’s hardness is in the same ballpark as Savannah’s, though the exact numbers depend on where the intake is and what the river’s doing that season. Both cities benefit from that metamorphic watershed, which is why neither one has the brutal hardness you see in limestone-fed systems.

Hilton Head and Brunswick are coastal, and that’s where things get different again. Coastal communities in the Lowcountry often blend surface water with groundwater sources, and some of those groundwater wells tap into limestone or shell deposits that push hardness up. Hilton Head in particular has water that runs harder than Savannah’s in many areas. Brunswick, being further down the coast, can vary by neighborhood depending on whether the supply is river water or well water.

The practical difference between Savannah at 4.1 GPG and a hard-water city at 10-plus GPG is real but not dramatic. You’ll use more soap and detergent than you would with soft water, and the WQA and Battelle found in their 2010 study that soft water can cut laundry detergent use by up to 50% and dish soap by up to 70%. But you’re not dealing with the scale buildup that shortens water heater life by 30-50% or costs the average affected household around $800 a year in energy and cleaning products, according to WQRF research. Savannah’s moderate water is the kind you can live with comfortably, maybe think about a softener if you’re picky about spots, but you’re not fighting the geology every single day.

How does Savannah stack up against the rest of Georgia? It's moderate at 4.1 GPG — Atlanta and Augusta sit nearby with different numbers. See the full hardest-water ranking for context.

Want the broader explainer on what hardness actually is and how it behaves? Read hard water vs. soft water, explained.