Mount Pleasant Waterworks (copy)

The deep well operation center for Mount Pleasant Waterworks is located in the Old Village at the corner of King And Simmons Streets. 

South Carolina is rich in fresh water, most of it deep underground in aquifers. Responsibly managing that wealth is arguably one of the state’s most important missions as we look to the future. But just how to do it is still largely a mystery.

The Department of Health and Environmental Control, responsible for managing and permitting groundwater withdrawals, has expanded its “Capacity Use Zone” program to better regulate pumping in areas of concern, including the Charleston area. But DHEC has yet to set area-specific limits on how much water can be safely withdrawn — something it needs to do to accommodate demand and, more importantly, ensure the long-term health of the aquifers.

“While there’s not an unlimited amount of groundwater in the South Carolina coastal plain, there is a lot of water,” Bruce Campbell, a groundwater specialist with the U.S. Geological Survey, told Post and Courier reporter Bo Petersen recently. “However, there are practical limits on how much can be extracted and extracted without causing problems.”

Some DHEC critics, however, have rightly pointed out that the agency rarely denies a groundwater withdrawal permit and its management strategy amounts to little more than well monitoring and the perfunctory scrutiny of permits.

Those tensions came to head last year when Google, already permitted to withdraw 500,000 gallons daily, asked to withdraw an additional 1.5 million gallons from the pristine, roughly 2,000-foot-deep Charleston aquifer for cooling servers at its Berkeley County Data Center. Public opposition and resistance from Mount Pleasant Waterworks, which draws from the same critically important aquifer, prompted the tech giant to put its permit on hold indefinitely.

Google’s own hydrogeologists, however, insisted the withdrawal wouldn’t harm the aquifer. They estimate 200 million gallons flow through it daily, and only about 8.3 million gallons are withdrawn in total each day.

That may be true, but a miscalculation could be devastating. In its latest budget request, DHEC said it needed additional staff “to assist with increasingly complex water-quantity planning issues, assess data, perform complex audits or participate in in-depth stakeholder processes.”

What happened in the Hilton Head/Savannah area should serve as a cautionary example. An overreliance on shallower aquifers there has caused saltwater intrusions that have ruined numerous wells over the past two decades. And the cost of replacing fouled freshwater supplies has run into the hundreds of millions of dollars.

By contrast, Mount Pleasant Waterworks officials realized water levels in the much-deeper Charleston aquifer were dropping precipitously in the late 1990s, largely due to pumping for the public water supply. That prompted the utility to back off and start buying water from Charleston Water System and rely more heavily on surface water. Since then, groundwater levels have been rebounding.

According to DHEC, groundwater usage in the tri-county area has declined since peaking around 2002, when the agency established its Trident Area Capacity Use Zone. That’s good evidence DHEC’s plan is working. But more needs to be done.

With mega-farms in the Aiken and Lexington areas tapping both ground and surface water supplies in increasing volumes, some shallower wells nearby have run dry over the past couple of years.

Funding for DHEC to hire two additional hydrogeologists – less than $200,000 — is pending before the Legislature as it finalizes a budget. The agency has just four hydrogeologists in its capacity-use program and 14 in the larger water bureau, which isn’t enough in a fast-growing state that continues to attract more residents and industries.

Lawmakers should ensure the agency gets what it needs to get a better grip on managing the state’s network of aquifers.

And DHEC must continue to work with the state Department of Natural Resources and the USGS to better understand aquifer flow models and establish safe withdrawal limits. Protecting one of our state’s most valuable natural assets must not be left to trial and error.