The City has initiated the third phase of a project to improve storm water and tidal drainage across the island. This project is intended to make significant drainage improvements to the 30th, 36th and 41st Avenue outfalls which will improve conditions on the amount of standing water events experienced by residents and property owners.
The project began in 2017 when City Council tasked the Planning Commission with developing a strategy to address drainage problems. As part of the project, smaller but impactful drainage improvement projects along the basin will also be addressed. These are located at Sparrow Drive, Forest Trail, Cross Lane, 32nd Avenue and 41st Avenue.
The construction of the 30th and 36th Avenue outfalls began in early 2022 and expected completion in 2023. The construction of the drainage improvements to the 41st Avenue outfall is scheduled to begin in the fall/winter of 2023.
Updates
Phase 3 Drainage Update - June 2023
30th Avenue
• Still waiting on delivery of check valves. Castings and grates are in and waiting for fabrication of miscellaneous items (railings, trash racks, etc.) All
installation to be completed at the same time with same crew.
36th Avenue (Forest Trail)
• Coordination and design of junction box still in process. Construction of 36th Avenue outfall to start in the fall.
41st Avenue
• MS4, NPDES, OCRM, USACE & SCDOT permits on hand.
• Terracon coordinating purchase of mitigation credits and Environmental Assessment w/ SCOR
• T&H prepared technical specifications and special provisions for bidding
• Start of construction planned for fall/winter 2023.
Phase 3 Drainage Update -May 2023
30th Avenue
• Check valves in final stage of production. Expected to arrive in 2-3 weeks.
36th Avenue (Forest Trail)
• Coordination and design of junction box still in process. Construction of 36th Avenue outfall to start mid-August
41st Avenue
• MS4, NPDES, OCRM & USACE permits on hand. SCDOT encroachment permit still in review.
• Terracon coordinating purchase of mitigation credits and Environmental Assessment w/ SCOR
• T&H prepared technical specifications and special provisions for bidding
• Start of construction planned for end of 2023
Phase 3 Drainage Update - April 2023
30th Avenue
• Completed final cleanup and stabilization at 30th Avenue. Pavement markings complete.
• Dominion Energy set up new utility pole and Comcast relocating lines from temporary pole
• No work expected in the next 2 weeks: waiting on drainage inlet tops, fabrication of all metal
hardware and check valves for 30th Avenue
36th Avenue (Forest Trail)
• Junction box design still in process. Possible 6-week production timeline. City waiting on
confirmation from junction box manufacturer on production timeline to decide whether to carry
on project this summer or delay until end of beach season
41st Avenue
• OCRM issued critical area permit on 1/4/23.
• USACE issued permit on 4/5/2023.
• Construction start date still feasible for year end
Comprehensive Drainage Master Plan
• D&F making progress on preparation of capital improvement prioritization plan, maintenance &
development of recommendations.
• Scheduling presentation to Council at May 9, 2023 workshop
Phase 3 Drainage Update - March 2023
30th Avenue:
• All utility work complete
• Box culverts has been installed
• All inlets and small diameter pipe is installed
• Driveway pour is complete
• Concrete placed on homeowners' side of sidewalk (in place of
existing asphalt)
• Homeowner indicated they were happy with the work
• Paving completed 3/9. Road reopened Friday, 3/10
• All pumps are off and have been relocated to Forest Trail location
36th Avenue (Forest Trail):
• Junction box design still in process. Possible 6-week production
timeline
41st Avenue:
• OCRM issued critical area permit on 1/4/23. Waiting on USACE
permit
Phase 3 Drainage Update - January 2023
30th & 36th Avenue:
• Road work and detour at 30th Ave &
Waterway Blvd to begin week of January
16th and last approx. 8-10 weeks. When
complete, contractor will move to complete
road work at Forest Trail and Waterway Blvd
41st Avenue:
• OCRM issued critical area permit on 1/4/23.
Next step is for the USACE to issue final
federal permit
• Kick-off meeting with Thomas & Hutton and
the SC Office of Resilience scheduled for
week of January 9th
Phase 3 Drainage Update - November 2022
30th & 36th Avenue:
• At 36th channel work adjacent to the golf
course is complete up to the cart bridge
• At 30th work completed up to a point near the
road where a pause is necessary to allow
coordination with Dominion Energy and the
construction of box culverts.
• Cart path behind 36th is prepped for paving
41st Avenue:
• Wetland permit (OCRM and USACE) still
pending. City has conditional approval from
OCRM. All other permits are contingent on the
wetland permit.
• City received $1.4M grant from the SC Office
of Resilience from CDBG-MIT funds for
construction.
• City received approval for additional $730,000
to pay for the extension of drainage pipes
along the edge of 41st Avenue into the marina
site.
Phase 3 Drainage Update - September 2022
30th & 36th Avenue:
- Golf course portion of the work completed
- Road work/closure at 30th Ave delayed due to box culvert approval process and 8–10-week manufacturing lead time
- Work on 30th Ave restarted the week of September 12th and expected to take two weeks to complete pipes between homes and up to the road.
- Contractor will then move to 36th Ave Outfall; once completed, will return to install junction box and box culvert at 30th Ave. (road closure work)
41st Avenue:
- Wetland permit (OCRM and USACE) still pending. City has conditional approval from OCRM. All other permits are contingent on the wetland permit.
- Project was put on public notice on April 14 until May 14.
- City received $1.4M grant from the SC Office of Resilience from CDBG-MIT funds for construction. City received approval for additional $730,000 to pay for the extension of drainage pipes along the edge of 41st Avenue into the marina site.
Phase 3 Drainage Update - August 2022
30th & 36th Avenue:
- Golf course portion of the work completed
- Road work/closure at 30th Ave delayed due to box culvert approval process and 8–10-week manufacturing lead time
- Work on 30th Ave expected in the next two weeks – contractor & engineer to install yard inlet to manage stormwater from yard of adjacent resident and complete installation of pipes between homes and up to the road.
- Contractor will then move to 36th Ave Outfall; once completed, will return to install junction box and box culvert at 30th Ave. (road closure work)
41st Avenue:
- Wetland permit (OCRM and USACE) still pending. City has conditional approval from OCRM. All other permits are contingent on the wetland permit.
- Project was put on public notice on April 14 until May 14.
- City received $1.4M grant from the SC Office of Resilience from CDBG-MIT funds for construction.
- City held kick-off meeting with Office of Resilience staff and Thomas & Hutton to determine next steps to get the project ready to go to bid once permits are in hand.
- Grant amendment request for the extension of pipe along 41st Avenue submitted.
Phase 3 Drainage Update - July 2022
30th & 36th Avenue:
- Golf course portion of the work completed
- Road work/closure at 30th Ave delayed due to box culvert approval process and 8–10-week manufacturing lead time
- Work on 30th Ave expected in the next two weeks – contractor & engineer installing yard inlet to manage storm water from yard of adjacent resident and complete installation of pipes between homes and up to the road.
41st Avenue:
- Wetland permit (OCRM and USACE) still pending. City has conditional approval from OCRM. All other permits are contingent on the wetland permit.
- Project was put on public notice on April 14 until May 14.
- City received $1.4M grant from the SC Office of Resilience from CDBG-MIT funds for construction.
- City held kick-off meeting with Office of Resilience staff and Thomas & Hutton to determine next steps to get the project ready to go to bid once permits are in hand.
- Grant writer and staff working on a grant amendment request for the extension of pipe along 41st Avenue.
Phase 3 Drainage Update - June 2022
30th & 36th Avenue:
- Construction started at 30th Avenue
- Golf course portion of the work completed by mid June
- Waterway & 30th road closure to start in Mid August
- Waterway & 36th road closure late September - mid October
41st Avenue:
- Wetland permit (OCRM and USACE) still pending. City has conditional approval from OCRM. All other permits are contingent on the wetland permit.
- Project was put on public notice on April 14 until May 14.
- City received $1.4M grant from the SC Office of Resilience from CDBG-MIT funds for construction.
- City held kick-off meeting with Office of Resilience staff and Thomas & Hutton to determine next steps to get the project ready to go to bid once permits are in hand.
- Grant writer and staff working on a grant amendment request for the extension of pipe along 41st Avenue