Approximately 30 years from the initial project planning to its current state of construction, the new North Millsboro Bypass connecting Route 113 and Route 24 is progressing on schedule.
The major infrastructure project will soon offer a safer and more efficient solution for Delaware’s swelling population, while simultaneously making it easier for agricultural products and tourists to traverse the notorious Sussex County bottleneck.
The project includes the construction of four bridges and an overpass, notably one that will span Millsboro Pond.
The new grade-separated, 2-mile, two-lane connector road — sitting approximately 20 miles from the Delaware and Maryland beaches north of the town of Millsboro — is expected to cost $140 million and is 100 percent funded through the Federal Highway Administration.
The team is constructing through a challenging, environmentally-sensitive area, and a lengthy and complicated permitting process required greater teamwork and patience.
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Delaware’s State Road 24 (SR 24) is a major east-west connector route servicing the beach resort area via the downtown district of Millsboro. It intersects with U.S. 113, a congested, signal-controlled intersection surrounded by commercial and residential development.
“Intersections such as these are typically being converted to a grade separation, however, due to the project’s large footprint and the potential environmental impacts, that option was not feasible at this location,” said George Pierce, Area Engineer/Construction Project Manager, Delaware Department of Transportation (DelDOT).
Instead, bypassing Millsboro to the north by realigning SR 24 with a grade separation at U.S. 113 and SR 20’s intersection was the preferred option.
The project begins at Route 24 west of Mountaire Farms and travels westward, with bridges over Gravel Hill Road, Millsboro Pond, the Norfolk Southern Railroad, and Fox Run Road. It will connect to Route 113 north of Millsboro.
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New Jersey-based Richard E. Pierson Construction Company (R.E. Pierson) won the bid on the contracts and is working to complete both concurrently.
“The project is essentially two big phases, with the off-alignment portion occurring during the first phase, then the tie-in, switch over, and existing road reconfiguration in the second phase,” Pierce said.
“We are targeting a late summer 2025 completion of the tie-ins and switchover of traffic from existing SR 24 to the new bypass [phase two],” he added.
The bypass route, however, crosses a highly sensitive environmental area over Millsboro Pond and the adjacent Doe Run Nature Preserve, encompassing more than 4,000 acres of land protected by the state. The waterbody feeds into the brackish, drowned river valley of Indian River Bay, lying between the barrier islands of Delaware and the inland wetlands.
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DelDOT was seeking to minimize the impacts of the roadway and bridge construction in this sensitive area. R.E. Pierson was selected and came on board to minimize the impact through innovative solutions.
“Their ideas and input were integral in obtaining the necessary environmental permits required to move forward with construction of this project,” Pierce said.
The overall project is a compromise drawn from over 20 years of environmental studies compiled by DelDOT regarding U.S. 113 and the bypass of Millsboro.
One of the challenging environmental issues was the presence of forest-nesting birds and an endangered striped mud turtle. The time-of-year restrictions for these two species overlapped, allowing tree clearing to occur only in August.
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DelDOT mitigated the striped mud turtle restriction by awarding an advanced work contract to R.E. Pierson, who installed a turtle fence, essentially a super silt fence product, around the forest clearing limits of the project.
“By placing this fence before the time-of-year restriction, we prevented the movement of striped turtles from the pond to the forested areas, allowing the turtles to nest elsewhere in the adjacent forest,” Pierce said.
This permitted the team to clear trees within the fenced area from April through September, instead of being limited to the one-month window in August.
- BR 3-594 (grade separation over U.S. 113 for bypass) - Traditional simple span steel girder, single pier, cast-in-place pier elements.
- BR 3-595 (bridge across Fox Run Road and railroad) - Traditional simple span steel girder, single pier, precast pier elements.
- BR 3-596 (western crossing of Millsboro Pond) - Top-down construction to minimize in-water footprint and eliminate need for a trestle/causeway. Concrete pile foundation, precast PCC pier cap, PCEF deck bulb tee with UHPC closure pour, standard concrete deck overlay.
- BR 3-597 (eastern crossing of Millsboro Pond) - Concrete pile foundation, precast PCC bathtub footings, precast PCC pier columns, precast PCC pier caps, precast PCC bulb tee beams with traditional PCC deck pour.
The onsite concrete manufacturing plant is currently up and running, and mainline paving has begun. Almost all of the earthwork has already been completed for the project.
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Bridge 3-596 was initially planned as a traditional causeway trestle construction, with an anticipated temporary impact of .04 acres of wetland and 1.10 acres of open water. One third complete, the bridge is being constructed in a top-down method.
“Based on input from R.E. Pierson, the design was changed to a precast top-down technique, which reduced both wetland and open water temporary permit impacts to zero,” Pierce said.
The team originally planned for Bridge 3-597 to be a combination causeway/trestle construction with an anticipated temporary open water impact of .07 acres, designed with suspended bathtub footings, which were precast and draped over the pile foundation for a closure pour. However, by eliminating the causeway and converting to a full pipe pile trestle, these impacts were reduced to .05 acres.
“This design removed the footing from resting on the bottom of the pond, greatly reducing the impact on this sensitive fish-spawning area,” Pierce said. “Our mitigation efforts on this bridge even included relocating any woody stumps or debris encountered during pile driving within the pond to ensure no loss of spawning habitat for game fish.”
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The eastern abutment of Bridge 3-594 over U.S. 113 has been completed, and work on the pier and western abutment foundations started in October. Bridges 3-595 and 3-597 both have the piers and abutments finished, and beam placement began in October.
Pierce said the contractor’s alternative bid was a challenge for DelDOT in itself, as it did not quite fit into the standard low bid process.
“It was a bit cumbersome, as many of the traditional steps and coordination needed with other agencies do not exactly align with the traditional preparation of our bids,” Pierce said. “While anything can be solved with time, this did cause some issues trying to get the contract executed quickly and in a specific time window to avoid schedule impacts from environmental time-of-year restrictions.”
According to Pierce, the Construction Manager/General Contractor (CM/GC) process itself does not have a good mechanism for performing preliminary construction engineering shop drawings, because the process does not guarantee the contractor selected for the CM/GC design phase of the contract is automatically awarded the construction portion of the contract.
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“While it’s helpful to brainstorm and formulate designs, a bulk of the shop drawing and construction engineering work cannot occur until post award of the construction contract, at which point the clock is ticking,” Pierce said. “In a project with three different bridge designs, and numerous precast elements, this makes for a very tight critical path centered around numerous submissions and reviews.”
Pierce recommends having both a Cooperative Design Consultant and Construction Engineer, because they will be heavily reliant upon each other to meet deadlines.
Being good neighbors to the locals, be they municipalities, legislators, constituents, or residents, is always of critical importance to a project’s success. Pierce mentioned that the close-knit environment of the Delaware community helped to keep the process quick and nimble.
“Delaware is lucky; we’re a small state, we have a consistent tenured staff with local ties, and a good working relationship within the area,” Pierce said. “If someone has a problem, they generally know who to call and can get a quick turnaround to avoid the small issues turning into major issues.”
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“I think this is a unique thing that DelDOT can bring to the table with our projects that is harder to accomplish at a project level in larger, more urban areas,” he said.
The bypass will be operational and open to traffic in the late summer of 2025. Commuters can expect existing roadway conversion and touch up work to last throughout early 2026.
