Sewee to Santee Septic Tank Study (2006)
For years, most of the 900 or so households in the rural northeast Charleston County corridor known as Sewee to Santee had bought their water in 1 or 5 gallon containers from stores in Georgetown or Mt. Pleasant. Water from their shallow private wells was undrinkable, with a very high iron and particle content that left rust-colored stains on white laundry after a few wash cycles.
As a result, most residents were paying about 400 times as much for their drinking water as residents of Mt. Pleasant, who got their water from a local utility.
A non-profit group made up of Sewee to Santee residents requested that a study be conducted of area households to assess septic tanks and water wells and usage. They needed the data to help them decide whether to support centralized public water and sewer hookups or a community-managed septic tank maintenance plan, or other possible solutions.
Fifty-five percent of the Sewee to Santee households meet federal poverty guidelines, and most drive 20-30 miles to reach their jobs. Several households lack indoor plumbing and rely on hand pumps and outhouses.
The land owned by the Sewee to Santee residents is part of an extraordinary, priceless 40-mile stretch of undeveloped South Carolina coastline that includes 73,000 acres of salt and brackish marshes and intertidal mudflats, six government-protected barrier islands, 20,000 acres of managed Santee River Delta wetlands, the Francis Marion National Forest, and the Cape Romain National Wildlife Refuge.
DHEC helped train Lincoln High School honor students who lived in the community to administer in-person surveys. The students ultimately surveyed around 300 households and collected water samples, which DHEC then tested. Among the survey results:
- Area septic tanks ranged in age from 1 to 51 years.
- 57 percent of the septic tanks had never been pumped out.
- Over 22 percent of the homes pumped their septic tanks at least once per year, which told us that they may be experiencing problems such as leaky utilities resulting in water overload, system overload, or failed drainfield lines.
- 17 percent used water softeners.
- 38 percent of homes flowed wash water to a back or side yard or a drainage ditch.
- Nearly 70 percent of homeowners surveyed supported the concept of a wastewater management system and were willing to pay between $5 and $20 per month for the service.
- Many of the homeowners understood how their septic systems operated, but a number of the systems needed replacement, repair or upgrades.
Results of Lab Tests, Septic System Inspections, and Soil Sampling
DHEC lab tests found that more than one-third of the wells sampled were contaminated with coliform bacteria. Six percent were contaminated with dangerous fecal coliform bacteria.
Failed septic systems that were inspected were far removed from waterways or freshwater or saltwater marshes in the area, and it did not appear that septic systems were contributing in any measurable way to microbiological contamination of waterways at the time, although the conditions could be disease vectors for insects and wildlife.
The soils in most areas of the region will support conventional or mound septic systems.
The Sewee to Santee study concluded that there was an urgent need to improve the potable water supply in the community, and it recommended these measures as possible solutions:
- Drilling deeper individual, private wells or constructing community wells operated as a utility
- Installing water softeners or of point-of-use devices (such as reverse osmosis units or distillation units that can treat up to 15 gallons of water a day for drinking and cooking)
- Bottled water delivered by a designated provider.
- Creation of a community septic tank management program that would allow residents to pay an affordable monthly fee to participate.
See the final report, Onsite Disposal System Evaluations in the Sewee to Santee (pdf).
Sanitary Situation Survey Form (doc) – This was the assessment tool used by the students who visited residents. Your town could use a similar survey as a first-step assessment tool.Hold Harmless Agreement (doc) - This form told homeowner that their yard would be disturbed during the inspection, that there could be some risk of damage to their septic system, especially older systems, from the inspection, and that the inspection would not guarantee future system performance.
For additional information, contact: (803) 898-4329 Fax (803) 898-4200