Site plans in South Carolina

What changes a site plan in South Carolina

Five South Carolina conditions shape a site plan before any local code is read. Each one adds a line, a row in the site data table or a reviewer to the drawing.

The seal is broad, and it attaches at filing. Section 40-22-270(3) requires plans, specifications, plats and reports prepared by a licensee, or under a licensee's direct supervision, to carry the licensee's seal when they are filed with public authorities ^[5]. The engineering exemption in Section 40-22-280 covers farm buildings, buildings that need no permit, and one- and two-family dwellings built to the IRC; assembly, business, educational, factory and industrial, high-hazard, institutional, mercantile, storage and utility occupancies are not exempt regardless of size ^[6]. A building official must refuse a permit for plans that would need an engineer's seal unless the applicant shows they were prepared by a licensed engineer or are exempt (Section 40-22-270(8)) ^[5]. A fuel, storage, retail or industrial building therefore reaches its permit with a sealed set, and the preliminary plan is the draft the engineer of record builds that set on.

Disturbed acreage sets the stormwater tier. Land disturbance of 1 acre or more, or less than 1 acre within a larger common plan, requires coverage under the NPDES construction general permit ^[1]. Sub-acre sites file a Notification (SCDES Form 2628 for non-coastal sites) ^[7]; sites of 1 to 2 acres file a simplified SWPPP under R.72-300 ^[8]; and at 2 acres or more the Comprehensive SWPPP "must be prepared by a licensed South Carolina Professional Engineer, Landscape Architect, Tier B Land Surveyor, or a Federal Government Employee" ^[1]. Coastal-zone sites within one-half mile of a coastal receiving water face heightened requirements and BCM coastal zone consistency review. Disturbed area is a row in the site data table from the first sketch.

Eight coastal counties add a state permit. The SCDES Bureau of Coastal Management, the former OCRM, covers Beaufort, Berkeley, Charleston, Colleton, Dorchester, Georgetown, Horry and Jasper counties ^[9]. Critical areas are coastal waters, tidelands, beaches and beach/dune systems, and all alterations require authorization ^[10]. A critical area permit is required to alter a critical area directly, and a coastal zone consistency certification is required where a separate state or federal permit is sought for an activity in the eight counties ^[9]. The setback line equals 40 times the average annual erosion rate, with a minimum of 20 feet landward of the baseline (Section 48-39-280; Regulation Chapter 30) ^[3], and a certified Critical Area Line may be valid up to 5 years and is often required by municipalities for building setbacks ^[9]. Both lines are drawn on the plan before pads and buildings are placed.

Permit homes moved on July 1, 2024. DHEC was dissolved into SCDES for environmental programs and DPH for health ^[11]. Onsite wastewater under R.61-56 now sits with SCDES ^[11], as do underground storage tanks under R.61-92 Part 280 ^[12], construction stormwater, drinking water and wells, air and the coastal program. Many regulations and agency pages still carry the DHEC name until they are amended.

Lowcountry ground constrains the layout. The 1886 Charleston earthquake is the source of the greatest seismic risk in the region ^[13], and USGS scenario modeling near Summerville shows high liquefaction hazard next to rivers and marshy areas and low hazard away from them ^[14]. A high water table limits septic systems and infiltration-based stormwater, and R.61-56 sets onsite system setbacks that include 75 feet from the delineated critical area line ^[15]. The preliminary plan places buildings and pads against those lines; the geotechnical and civil engineers of record design the foundations, septic systems and stormwater.

Approval layers: state, county and city

South Carolina delegates land use power through one statute: the Local Government Comprehensive Planning Enabling Act of 1994, codified at Title 6, Chapter 29 (1994 Act No. 355) ^[16]. It authorizes counties and municipalities to create planning commissions, adopt zoning ordinances and land development regulations, and create boards of zoning appeals and boards of architectural review ^[16]. Municipalities govern inside corporate limits, counties govern unincorporated areas, and a parcel is subject to only one general-purpose zoning jurisdiction. Some counties historically had limited or no zoning in rural areas, so subdivision and stormwater regulations may still apply where zoning does not.

In Charleston, the Technical Review Committee coordinates Planning, Fire, Stormwater, Traffic and Transportation and other departments in one review ^[19]. Subdivision review governs the division of land, site plan review governs development of a single parcel, and a land disturbance or land development permit governs grading and stormwater; the three usually run concurrently.

Who prepares and seals what

South Carolina separates drafting a plan from taking professional responsibility for it. Section 40-3-20 defines responsible charge in the architecture act as the architect's direct control and personal supervision of the work ^[20], and Act 259 of 2016 added language under which a licensee's seal and signature certify that the document was prepared by the licensee or the licensee's agent ^[21]. The preliminary site plan is the unsealed first draft; the client's engineer, architect and surveyor of record build the sealed set on it. For the division of work in plain terms, see who prepares a site plan and the site plan architect page.

If the documents are signed by authors with their true occupational titles, the architecture act does not apply to farm buildings; to buildings of less than three stories and fewer than 5,000 square feet of total floor area, except assembly, institutional, educational and hazardous occupancies regardless of area; or to one- and two-family dwellings, including townhouses, within the prescriptive SC Residential Code (Section 40-3-290) ^[2]. The 2021 amendment (S.500, effective May 17, 2021) narrowed the dwelling exemption to that prescriptive scope ^[25], and joint board guidance requires a design professional for any assembly building regardless of size ^[26]. Section 40-22-280(C) preserves any local ordinance that independently requires a sealed plan ^[6].

Statewide overlays

Under the Beachfront Management Act, BCM reviews the baseline and the 40-year setback line every 7 to 10 years, and the current statewide review runs in three geographic areas from 2024 through 2027 ^[34]. Myrtle Beach keeps a policy of retreat based on erosion and amends its own baseline and setback line when BCM amends the state line ^[35].

Top jurisdictions

Digital submittal is standard in the larger jurisdictions, but the platforms differ: Tyler EnerGov in Charleston, Berkeley, Columbia and Spartanburg County; eTRAKiT in Greenville County; Click2Gov in the City of Greenville; OPAL in Mount Pleasant; CitizenServe in Summerville.

City of Charleston. The Technical Review Committee coordinates multi-department review of site plans and subdivisions for code compliance; plans are uploaded to the CSS portal for eReview, and each plan must be certified by an SC-registered architect, engineer, landscape architect or surveyor ^{[19, 24]}. The Board of Architectural Review reviews all new construction, alterations and renovations visible from the public right-of-way in the historic districts, and all demolitions of buildings 50 years or older south of Mount Pleasant Street ^{[37, 38]}.

Asset registries

Where a row gives no state rule, the rule is set by the county or city. No state RV park design rule has been verified for South Carolina: the state layer found is onsite wastewater, and the density and site size examples below are local ordinances.

For density arithmetic against local caps like these, see RV sites per acre. Asset detail sits on the national hubs for RV parks, campgrounds, glamping, gas stations, car washes, hotels, marinas, self storage and industrial sites.

Timelines and bottlenecks

Where a South Carolina jurisdiction publishes its own review time, these are the figures: Rock Hill returns development plan comments in about 10 business days ^[51], York County returns plat comments in about two weeks ^[48], Summerville's maximum review time is typically three weeks ^[50], and Mount Pleasant's plan review lead time is 4 to 6 weeks with no expedited option ^[49]. Berkeley County sells expedited review at $2,500 per department for two rounds ^[40]. Rezonings and planned development districts go to council, typically by three readings.

The resubmittal causes that recur across South Carolina:

• Stormwater plan deficiencies, and a C-SWPPP preparer without one of the qualifying licenses on a site of 2 acres or more ^[1].
• SCDOT encroachment sequencing and traffic impact study scoping under ARMS, which can run on a separate clock from local review ^[28].
• Critical Area Line determinations; a certified line is valid up to 5 years and is often a prerequisite for local setbacks ^[9].
• Wetland delineation timing with the Corps Charleston District.
• Septic feasibility in the Lowcountry, given the high water table and R.61-56 setbacks such as 75 feet from the critical area line ^[15].
• Board of Architectural Review aesthetic review in Charleston across conceptual, preliminary and final stages.
• Water and sewer capacity and tap availability.

Each item can be checked on the concept, before the engineer of record starts design.

Proof points

Recent outdoor hospitality cases on the Horry County coast show the rezoning path for RV parks:

• Waccamaw River destination park, Highway 905. On September 3, 2024, the Horry County Planning Commission approved rezoning a 34.47-acre tract on Highway 905 near Highway 22 to DP Destination Park, planned for about 200 campsites and 35 cabins on the Waccamaw River ^[59].
• Second Highway 905 proposal. A separate 98-acre Highway 905 proposal for 158 RV sites advanced through the Planning Commission, with three council readings required ^[60].
• Existing comparable. Sun Outdoors Myrtle Beach (formerly Carolina Pines) on Highway 90 operates in the same submarket ^[60].

Model projects in other states, including RV parks and resorts, are under case studies.

What the preliminary plan carries in South Carolina

A preliminary site plan from the studio is a detailed first draft of the project without the engineering layer: site layout, buildings and floor plans, internal roads and drive aisles, parking, pads and units, and the yield, organized with a site data table. In South Carolina that table carries the rows reviewers check first: disturbed acreage against the 1 and 2 acre stormwater tiers, the critical area line and setback line in the eight coastal counties, onsite wastewater setbacks, SCDOT frontage, and zoning and density against the local cap.

Stormwater design and the C-SWPPP, onsite wastewater engineering, utility design, SCDOT access design and the sealed building set are not included; the client's engineer, architect and surveyor of record produce and seal them on top of the preliminary plan. Developers take the plan to the county or city at concept and pre-application (see where unsealed site plans are accepted), to a lender, and to a general contractor for pricing. The preliminary versus final site plan guide shows where the handoff falls, and the site plan consultant and site plan services pages describe the work. Background reading: stormwater as a site plan variable, coastal zone requirements for waterfront projects and the RV park regulatory matrix.

Neighboring state pages: Georgia and North Carolina. York and Lancaster counties draw growth from the Charlotte metro. All covered states are listed under service areas.

By Viola Sauer, Principal, Innowave Studio