A report by South Carolina's Floodwater Commission released Monday puts forth suggestions long made by environmentalists — that planners should work to preserve wetlands and prepare for flooding on a watershed level.
It also promotes some relatively novel ideas: an artificial reef placed offshore as a way of reducing beach erosion and a 400 acre man-made lake to store water.
The recommendations come after months of work by the commission, which was announced by Gov. Henry McMaster in October and convened for the first time in December.
The report will be opened for 60 days of public comment, and the commission will issue its final recommendations in November.
"This is the starting point. This is not an end point," said Tom Mullikin, the chair of the commission. "We’re creating a plan we want to continue to encourage robust comment and discussion on."
Among the initial recommendations are:
- Better drainage maintenance, coordinated though local groups like the task force in Charleston County.
- Identifying "high-priority floodplains, wetlands and open spaces" and preserving them, while encouraging natural solutions to store water in other areas.
- Constructing up to two artificial reefs along the coast to study their effectiveness.
- Protecting the electrical grid by putting lines underground and requiring health care facilities to have backup generators.
- Building new reservoirs and "channelizing," or excavating, rivers.
- Developing a program to help local governments secure federal funding for flood protection.
Some of the ideas explored by the commission have already been underway. For example, two state agencies are in the midst of a multi-year process to create standards for living shorelines. That idea was the subject of an entire sub-group on the task force.
Engineered oyster reefs and augmented marshes are considered by many scientists a gold-standard method to avoid shoreline and riverbank erosion. The report goes further, however, suggesting that land near marshes should be preserved to account for migration upland as the sea level rises.
Other ideas are less tested. The first-draft proposal to build an artificial reef, released months ago, equated what would be a highly-engineered, near-shore speed bump for waves with the deep-water "reefs" that South Carolina has already created for fish habitat.
Those reefs, often made of sunken ships or metal containers, would be too far below the surface to affect wave energy.
Ultimately, the commission has suggested more study on that subject, said Mark Robertson, director of The Nature Conservancy in South Carolina. Robertson worked on the reef sub-group.
"We know that (tropical) coral reefs can reduce up to 90 percent of wave energy, so that works. But that's a very different environment than in South Carolina," Robertson said. "At this point in my mind, it’s a concept. It’s not yet a plan."
At the same time, recent recommendations made by the group behind the Dutch Dialogues, a flooding study panel examining the Charleston area, essentially ruled out tidal gates.
The expensive, highly-engineered gates would have the same goal: slowing down or stopping wave energy in the case of storm surge. But the cost would be astronomical, especially in the Lowcountry's complicated network of rivers and sea islands, engineers said in the Dutch Dialogues presentation in July.
The state commission, Mullikin has previously said, is focused entirely on dealing with the on-the-ground reality of flooding, not the climate change that's making it worse. As average temperatures in South Carolina and elsewhere rise, scientists largely agree that storms will dump more rain and seas will get higher.
Earlier plans on the state and local level to address the carbon emissions behind rising temperatures have mostly fallen by the wayside.
In the case of the flood commission, Mullikin said, "it's going to require a number of pieces coming together for a holistic response."