Church Creek Drainage Basin

Community Education

• Interactive StoryMap of Church Creek Basin: The StoryMap highlights the City’s flood mitigation projects of voluntary buyouts, nature-based solutions, and green infrastructure to reduce flooding in the Church Creek Basin. These projects also provide added benefits such as improved stormwater management, enhanced wildlife habitat, and new community amenities. Link here.
• Self-Guided Tours at Bridgepointe: The City partnered with The Nature Conservancy of South Carolina to create a self-guided tour at the new 6-acre Bridgepointe Ecological Park in the Church Creek Basin. The site was formerly home to 32 flood-prone townhomes. The City acquired and demolished the properties as a voluntary buyout. The site was then transformed into a neighborhood park that also increased the capacity for stormwater storage. Visitors can listen to the self-guided audio tour using the link here or scan QR codes on park signage once on site to begin the tour.

Background

The Church Creek drainage basin today drains a total of area of over 10,000 acres located along the western side of the Ashley River. This area has been studied for over 20 years, and its flat terrain made it difficult to estimate the extent until the advent of modern high-resolution topographic information. We can now appreciate that historically, the area of watershed was much smaller. Early ditches, road construction, and stormwater management have redirected water towards Church Creek and away from other flow paths, enlarging the drainage area. 

The area that flows into Church Creek today was once composed mainly of marsh and lowland hardwood forests that were ditched and converted to rice fields and phosphate mines. Today the lower sections of the basin  are largely developed. The residential neighborhoods of Shadowmoss, Hickory Hill, Hickory Farms, Grand Oaks, Village Green, Forest Lakes, and Canterbury Woods fall within the Church Creek watershed. Church Creek passes through these neighborhoods in straightened ditches and flows down to marsh and then into the Ashley River under U.S. Highway 61 and the Seaboard Systems Railroad. Upstream of the Seaboard Systems Railroad, portions of the existing channel have been improved between Bees Ferry Road and the railroad.

Project Timeline

To date, the City of Charleston has spent more than $4 million on constructing improvements and monitoring the impact of stormwater runoff from new developments to ensure it does not negatively affect existing areas. Committed to addressing ongoing drainage challenges in the basin, the City continues to update the ICPR model, review proposed development plans for compliance with stringent stormwater standards, maintain the existing collection and conveyance system, and pursue additional capital improvement projects to enhance drainage.

• 1990’s
  • New homes were constructed in the Still Shadow section of Shadowmoss. Throughout the 1990s these new homes were flooded during several rain events. After determining that the accepted engineering standards applied to stormwater system design were not effective in this drainage basin, the city approved a nine-month building moratorium and initiated a detailed study of the drainage basin.
• 2001
  • The City, through its consultant, developed an ICPR model of the basin which was calibrated through comparison of known flood events. The study resulted in new design standards for new development in the basin and recommendations for system improvements that could lower flood levels.
• 2005
  • Capacity was added to provide additional stormwater storage in conjunction with construction of the Middleboro section of Shadowmoss.
• 2007
  • The City completed a diversion project that intercepted a significant portion of stormwater runoff from the eastern side of Shadowmoss Plantation. The new system included a new canal and dual 4 by 8 feet box culverts which created a second outfall to Church Creek.
• 2010
  • The City constructed a 4 by 12 box culvert to add additional capacity from the Bridge Pointe pond to the main channel.
• 2017
  • After several flooding events in succession, the City began coordinating with FEMA to buy the Bridge Pointe Town Homes site and convert it to open space.
• 2019
  • The Dutch Dialogues' focus on Church Creek is listed in the final report located here. The City led a grant application to the National Fish and Wildlife Foundation's (NFWF) Emergency Coastal Resilience Fund for Habitat Restoration and Flood Protection. The Grant was successfully submitted with community partners such as the Nature Conservancy and Clemson Extension. 
• 2020
  • The City released new stormwater regulations for the basin to minimize the flood risk associated with development. They include comprehensive site planning and the integration of low impact design approaches that decentralize stormwater management. 
  • The City also hired a consultant team to undertake wetland design on select properties owned by the city or collaborative partners in accordance with the NFWF grant.
• 2025
  • The City completed work on the Bridge Point and Mowler Court improvements.