Water Hardness Atlas ZIP / postcode

Well water hardness in Delaware

Across 3 counties of Delaware, the median well sampled by the USGS has 3.3 gpg of hardness. Counties range from 2 gpg (Sussex County) to 4.9 gpg (New Castle County).

Millions of American households drink water from their own well. No utility tests that water and no water quality report covers it. These pages summarise the hardness the U.S. Geological Survey measured in wells county by county, so you know what to expect before you test your own well.

Counties, hardest first

gpgmg/Lwells
New Castle County4.983255moderately hard
Kent County3.35773soft
Sussex County235401soft

Counties with fewer than 10 sampled wells, or a median outside 5–500 mg/L, are not shown until the figure is reviewed.

Delaware: tap water hardness by city → · Well water hardness by state and county →