PROJECT DESCRIPTION: The Gates, a new residential development on S-22 (Orangeburg Rd), located approximately 1,000 LF south of S-58 (W. Butternut Rd), required a left turn lane for its entrance. The engineer-of-record for the new development submitted an encroachment permit for the left turn lane and new entrance, and after receiving the initial comments on the encroachment permit, contacted J. Bragg Consulting to perform the roadway and drainage design to SCDOT’s standards and specifications for plan development as well as coordinate the approval for the encroachment permit.

CHALLENGES: Since the roadway improvements were for a new development, they were designed to remain within present right-of-way (R/W) or on the development’s property. Since this area of Orangeburg Rd consists of elevation differences between the roadway grade and adjacent properties (i.e.  existing properties are higher than the roadway), the design required an atypical section and other solutions as follows:

• 2-ft paved shoulder on right side of road (opposite side from development) with no additional improvements 
• 11-ft widening to the left (development side) with 2-ft paved and 4-ft grassed shoulder with 4:1 front slope and 2:1 back slope or with 3-ft valley gutter and 3-ft grassed shoulder with 3:1 back slope
• Maintain 11-ft travel widths and resurface with other improvements
• Match or exceed existing clear zone widths
• Improved drainage on left side, retain existing drainage on right side and retain existing crossline pipe
• Coordination with two properties for driveway reconstruction

RESPONSIBILITIES: J. Bragg Consulting performed roadway and drainage design for the improvements on S-22 (Orangeburg Rd) and approximately 250 LF for the entrance road.  The final construction plans included sight distance detail for the new entrance, typical section sheet, general construction notes, plan and profile sheets, pavement marking and sign plans, maintenance of traffic plans, pre- and post-drainage information for S-22, erosion control data sheet, cross sections.  The plans were prepared to SCDOT’s standards.  In addition, a future 60’ R/W is preserved by the developer for the widening of S-22.

The plans were also coordinated with the residential development. An all-inclusive MS4/land disturbance package was prepared by the engineer-of-record for the residential development and associated roadway improvements.  The MS4/land disturbance permit along with clear zone exhibit, final construction plans, traffic impact analysis and concurrence e-mail, performance bond, drainage report and geopak drainage information were submitted to obtain the encroachment permit.

Construction phase services were provided to address contractor’s questions, assist with retaining the Dorchester County Water Authority’s line in-place, and submit final documentation for encroachment permit close-out.