For the initial settlers of the Charleston area, finding fresh water was easy – all you had to do was dig, and not very deep. The peninsula lies atop a 18-20 foot strata of sandy soil that underneath has bed of hardened clay marl impervious to water, and soaking rains fill this strata enough that a twelve-foot well should provide plenty of water. A water problem emerged with population growth and pollution, as wells on adjacent lots competed for the same water, while outhouses drains dumped harmful bacteria into the water system.
By the 1820’s steam technology and improved digging implements allowed for probing through the marl into the ancient aquifers deep in the substrata of the coastal plain. There, tons of water flows daily, creating enough pressure to create springs where the layers of subterranean rock come closest to the earth’s surface.
The initial artesian wells, drilled to 300-500 feet, had little success, but by 1880, a series of wells stretching as far as 1700 feet produced millions of gallons of water. The pressure from the flowing depths were strong enough to fill receiving reservoirs and twelve miles of street mains with 165 hydrants by 1881. Tests done by Charleston health officials on the chemical make-up of the water in the 1880’s proved that the underground water was cleaner than rain water, and the artesian wells on Calhoun and Wentworth street were a regular filling station for Charlestonians until Hurricane Hugo damaged the wells in 1989.
One of the fascinating things that Charelstonians learned from the ever-flowing water, was that it varied in strength according to tides. Many of the artesian springs bubble up under the sea, and when the tides are high the pressure on top of the springs holds back the flow, so that it moves faster through other openings, and vice versa.