Mossy Oaks Stormwater Drainage Project
Suffering from repeated flooding during heavy rains, king tides and storm surges, Beaufort’s Mossy Oaks neighborhood, home to 1,500 houses, experienced many drainage challenges. The issues of inadequate pipes and overgrown ditches were compounded by the vulnerabilities of slab-built homes, and after the neighborhood suffered three damaging floods in 11 months, Beaufort identified it as the top priority for mitigation among its flood-prone areas.
The city created a multijurisdictional task force for the effort, including the Town of Port Royal, Beaufort County, state agencies, utilities, nonprofits, neighborhood groups and the U.S. Army Corps of Engineers. Over several years, the city conducted an engineering study and identified funding, including $5.9 million from bonds, $1.5 million from grants and $580,000 from community partners.
The project installed improved drainage pipes at corrected elevations and tidal flap gates to control water flow into the marsh. After permitting and bidding, the construction took nine months — two months less than planned — and was completed under budget. The numerous partnerships involved in the effort allowed for utility collaboration, so that new water, sewer and electrical lines could be installed during construction. Ongoing outreach efforts and two-way communication with residents meant that those affected by construction were kept informed of the process.
Since completion of the project, Mossy Oaks has experienced no significant flooding, even during a storm event that dropped 7 inches of rain in less than 24 hours. For future stormwater projects, Beaufort will use the planning, construction and communication methods employed for Mossy Oaks as it addresses one of the objectives in its strategic plan: “plan for sea-level rise.”