Phase 3 Drainage Project - Outfalls & Basin
Milestone timeline:
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.
Project Updates
30th Avenue
- Contractor on site installing tide check valves, tide gates, trash racks and grates on the junction box.
36th Avenue (Forest Trail)
- Construction to start immediately following Labor Day weekend.
41st Avenue
- Pre-bid meeting – August 23, 2023. Deadline for bids– August 30, 2023.
Comprehensive Drainage Master Plan
- Davis & Floyd updating executive summary for report to be completed and distributed.
Waterway Boulevard Multi-use Path Elevation Project
RFP for design, permitting, bidding and construction administration is out. Deadline for proposals – August 18, 2023.
Waterway Boulevard Multi-use Path Elevation Project
- RFP for design, permitting, bidding and construction administration is out. Deadline for proposals – August 18, 2023.
Phase 3 Drainage 30th, 36th & 41st Avenue Outfalls 30th Avenue
- Check valves have been delivered and are on site. 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 agreement on conceptual design of junction box complete. Construction of 36th Avenue outfall to start in the fall. 41st Avenue
- MS4, NPDES, OCRM, USACE & SCDOT permits on hand.
- Environmental Assessment completed and approval of grant funds for purchase of wetland credits approved
T&H prepared technical specifications and special provisions for bidding - Start of construction planned for fall/winter 2023.
Comprehensive Drainage Master Plan
- Maintenance review and development regulations review and recommendations in progress
- Waterway Boulevard Multi-use Path Elevation Project
- Staff developing Request for Proposals for the City to engage engineering firm to perform pre-award costs for engineering and permitting in accordance with FEMA’s Hazard Mitigation Grant Program specifications.
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.
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
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
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