Facing creeping saltwater plumes and little progress in reaching an agreement with Georgia to curb draining a local freshwater aquifer, Hilton Head Island water utilities are planning -- and digging -- for the future.
The South Island Public Service District is in the midst of a $10-million improvement and expansion that began in September. The project includes replacing pumps, installing new pipes and adding three wells.
The district plans to build a 620-foot-deep well near Cordillo Parkway for about $500,000. It could draw as much as 526 million gallons per year from the less-used Middle Floridan Aquifer, according to district operations manager Brad O'Keefe.
The project awaits permit approval from the S.C. Department of Health and Environmental Control, but construction could begin in May, O'Keefe said.
Most wells on Hilton Head draw from the Upper Floridan Aquifer -- 150 to 250 feet below sea level -- which holds freshwater like a sponge and is replenished naturally by rain water.
However, overpumping in parts of South Carolina and Georgia -- particularly in Savannah -- have caused saltwater to seep into the aquifer in some parts of the island and near Port Royal Sound, contaminating wells, according to a DHEC study.
The proposed South Island well would draw brackish water from a deeper aquifer, requiring treatment at the district's reverse-osmosis plant to remove the salt. The district built the plant in 2002, and it filters 2.88 million gallons of water per day that is pumped from a well 3,800 feet underground. The district uses between 5 million and 9 million gallons of water per day.
The new well will serve as a backup for the district's deep well and 11 Upper Floridan wells. O'Keefe said the district lost one well to saltwater intrusion in Long Cove Club about three years ago.
Other wells may follow, according to DHEC models.
"Just like the north end, saltwater intrusion is creeping in all the time, so we're trying to stay ahead of the game," O'Keefe said.
Hilton Head Public Service District, which provides water and sewer service to the island's north end, has lost six wells to saltwater intrusion since 2000 and expects two of its remaining five to become unusable next year, according to Pete Nardi, district spokesman.
Nardi said losing more wells appears to be inevitable, and the district has been gradually incorporating alternative water sources, such as treated Savannah River water purchased from the Beaufort-Jasper Water & Sewer Authority and treating Middle Floridan water in a reverse-osmosis plant. It also pumps fresh water it buys from BJWSA during months of low demand into mid-level aquifer wells, where it is stored; the water is drawn during the summer months of peak demand.
The South Island district is building two similar storage wells capable of holding 120 million gallons each.
Broad Creek Public Service District, serving mid-island residents, has not lost wells to saltwater intrusion, general manager Rusty Hildebrand said.
Committees from South Carolina and Georgia, created in 2005 by the governors from both states to study the saltwater intrusion in the Upper Floridan Aquifer, have been unable to reach a solution.
South Carolina spent months threatening to sue the Peach State if it wouldn't reduce water consumption from the aquifer. Utilities serving the Savannah area pump about 52 million gallons per day from the Upper Floridan; S.C. pumps about 10 million.
Tensions appeared to be coming to a head this winter, but the legal punches were never thrown, and such actions are -- for now -- off the table, according to Dean Moss of the S.C. Governor's Savannah River Committee.
Moss said he doesn't know if the legal threats moved negotiations forward, but the two sides are still working together.
Attempts last week to reach a representative from the Georgia committee were unsuccessful.
Suing Georgia would have meant spending a lot of time and money, without any progress on slowing the intrusion, Moss said.
A lawsuit between South Carolina and North Carolina over water drawn from the Catawba River, which runs near Charlotte into Upstate South Carolina, took four years to settle.
Moss described the current process to curtail saltwater intrusion as "slow," "painful" and "like a chess game."
Follow reporter Brian Heffernan at twitter.com/IPBG_Brian.