DESIGN CHALLENGES
Existing Soil Profile
Much of the property now known as Laurel Island was originally tidal marsh. Starting in the 1940s, the property was used as a dredge spoil disposal site. In the 1970s, the property was re-adapted to serve as two separate landfills which were known as the Romney and Holston landfills. Accordingly, subsurface conditions generally consist of municipal solid waste (MSW) underlain by soft, fine-grained dredge spoil and marsh deposits followed by the older and stable Tertiary deposits of the South Carolina Coastal Plain (i.e., the Cooper Group).
The MSW, dredge spoil, and marsh deposits are all highly compressible, and any additional weight such as roads, dirt, buildings, etc. will cause the ground surface to settle. This requires engineered solutions that will offset the negative effects of settlement.
Due to the amount of fill that has been placed on Laurel Island, the current elevation of the ground is some of the highest in all of Charleston at elevation 21. With the high ground and the engineering solutions available to manage the settlement, Laurel Island will become one of the most resilient developments in the Charleston area.