A Critical Area Line (CAL) is the boundary between the upland and the Tidelands/ Coastal Water critical area, and any activities seaward of the CAL may require a critical area permit. CALs are determined by SCDES BCM staff upon request and are valid for five (5) years from the date the CAL is certified by SCDES BCM staff  

SCDES requires a current, Department-certified CAL for the following activities 

• Erosion control structure (ECS) within the Tidelands critical area 
• Recreational docks over 900 linear feet 
• Living shorelines if they are located at the marsh/upland interface 
• Boat ramps 
• Stormwater permits on lots adjacent to the Tidelands 
• Septic permits on lots adjacent to the Tidelands  
• Port activities; and 
• Public infrastructure projects (e.g. SCDOT roadway projects) 

Local governments can require a certified CAL for a variety of activities including erosion control structures, construction with buffers and setbacks, planning, subdivisions, and real estate transactions. CAL establishment and/or review can additionally be requested for general interest.  

A CAL request can be submitted via ePermitting using the BCM Critical Area Activities application form. The applicant will have the ability to request a critical area line independently or request a critical area line in conjunction with another BCM activity, such as an erosion control structure. The applicant should follow the form and answer all form questions.