In the summer of 2020, a heavy rain overwhelmed an existing triple-pipe culvert under Sagamore Drive in the Lake Royale community in Louisburg, NC, flooding the road. A pipe joint of the center culvert separated, while roadway fill above it washed away. A sinkhole, 14 feet across and five feet deep, formed in the middle of the road. The drainage ditch along the south side of the roadway was also badly eroded.

To determine the best and most cost-effective method of replacing the culvert and repairing the road, A&O performed a design study of three options. After considering the options, the client chose a set of three 12x12-foot reinforced concrete box culverts to replace the existing triple-barrel culverts. The solution offered a “no-rise” scenario and reduced the frequency of rain overtopping the road to a 50-year storm event.

For the design phase of the project, we consulted with a geotechnical engineer and provided erosion control design, roadway plans, final construction documents with complete specifications, and a cost estimate. We developed final hydraulic modeling and documentation for submittal and approval by Franklin County Floodplain Management.

We managed the bidding of the project and are currently managing construction administration, providing construction observation, final inspection, and close-out documentation.

Overview
Client: 

    Lake Royale Property Owners Association
Location: 

      Lake Royale, Louisburg, NC
Subconsultants

  GC Mapping – Land Surveying

  Geotechnologies – Geotechnical survey
Contact:  

 George Cooper Jr., CMCA, AMS, PCAM

  General manager, LRPOA

  252-478-4121 ext 150
Design fee:

    $52,620
Construction cost:

    $870,170
Start/completion:  

    6/2020 – 6/2021
Project manager: 

      Glenn Zeblo, PE

  Experience
  Flood study
Drainage design
Culvert design
Roadway Repair Design
Construction documents
Civil-site design
Coordination
Construction administration

Relevant Image

Lake Royale - Day After Storm

The water was still high at Lake Royale the morning after a storm caused the failure of a triple-barrel culvert and the formation of a large sinkhole in the road above it.

Lake Royale-Sinkhole

Heavy rains from a storm in summer 2020 caused a pipe joint in the culvert below the road to separate, and a 14-foot wide by five-foot deep hole formed in Sagamore Drive in the Lake Royale community in Louisburg, NC.

Box Culverts Installed

The Lake Royale Property Owners Association chose to replace the failed culverts with three reinforced concrete box culverts, 12-foot by 12-foot each.

Box Culverts

The Lake Royale Property Owners Association chose to replace the failed culverts with three reinforced concrete box culverts, 12-foot by 12-foot each.