Work is underway to extend two stormwater drains off Rehoboth.

Beaches in Rehoboth and Dewey have been undergoing replenishment since mid-November, and the final phase of the $11.2 million project – the extension of two stormwater outfall pipes at Virginia and Maryland avenues – began Monday, March 6.

Stephen Rochette, spokesman for the U.S. Army Corps of Engineers, said two stormwater outfall pipes at the ocean end of Maryland and Virginia avenues is scheduled to be completed by June.

According to bid documents, this portion of the project costs more than $1.6 million and includes 108 feet of 30-inch pipe at the Virginia Avenue outfall, 54 feet of 36-inch pipe at the Maryland Avenue outfall and a total of 20 pipe supports.

Five stormwater outfalls empty into the ocean in Rehoboth at Virginia, Maryland, Rehoboth and Delaware avenues and Laurel Street. The extension of these two stormwater outfalls has nothing to do with the proposed $52.5 million wastewater ocean outfall near Rehoboth Beach.

Rochette said extending the stormwater outfalls requires erecting a cofferdam to provide for dry working conditions and the installing of new ductile iron pipe extensions. The cofferdam, he said, is removed after the work is complete.

Rochette said the crew will be working on one pipeline at a time and there will be a 200-foot-wide section of beach, from the Boardwalk to the shoreline, closed during construction.

Great Lakes Dredge & Dock Co., the same outfit that pumped 650,000 cubic yards of sand onto the beach in Rehoboth and Dewey late last year, has been hired for this portion of the project, said Rochette.

Dune crossovers, fencing and grass planting

Crews have been busy working on dune crossovers, dune grass planting and sand fencing in the months since the show-stopping heavy equipment associated with the beachfill portion of the replenishment project was completed Dec. 23.

Rochette said pedestrian, vehicular and ADA-accessible crossover work in Rehoboth was completed Feb. 27. Bid documents have the estimate for the crossover work coming in at roughly $225,000.

Users of the crossovers will notice the paths are not just sand. Rochette said the mixture for the crossovers is clay and sand for the pedestrian crossovers, while the vehicular and ADA crossovers have a bed of stone nine inches thick under the clay/sand mixture.

Rochette said sand fence installation and dune grass planting are expected to be completed by April 1. There will be 8,000 linear feet of fence installed in Rehoboth and 1,800 linear feet of fence in Dewey.

Rochette said approximately 91,040 dune grass plugs will be planted over 22,760 square feet of dune by the time it’s all done. He said the estimate is based on 100 plugs for every 25 square feet of dune.

The cost for sand fence and dune grass installation is a little more than $201,000, said Rochette.

The contract completion date per the contract is Aug. 31, but Rochette said the contractor is anticipating July completion based on good weather and no equipment breakdowns or design issues.

This replenishment was part of a federal and state partnership that renourishes the beaches every three years. The 50-year program, which has 30 years remaining, calls for the corps to pay 65 percent of the cost, while the Delaware Department of Natural Resources and Environmental Control pays the remaining 35 percent.