Rehoboth stormwater outfall repairs tally nearly $1 million

Beach replenishment in Rehoboth Beach is anticipated to begin later this month, and as part of that project, the U.S. Army Corps of Engineers will repair two stormwater outfalls at the north end of the Boardwalk.

Mayor Sam Cooper said outfalls at Grenoble Place and Maryland Avenue have been damaged but have remained functional for nearly eight years. Cooper said wave action has caused damage primarily to the support pilings. He said the city has been relying on temporary fixes, such as cutting the pipe down to keep it out of the water, to avoid further wave damage.

The city will pay $946,000 in budgeted funds towards the project, which will be added as an alternate to the beach replenishment project. The base cost of the beach replenishment is $8 million, although options on the contract with Great Lakes Dredge and Dock could push the total to $12 million.

Steve Rochette, spokesman for the corps, said, “We are still in the process of evaluating the outfalls at those locations and working out the details, but it is going to be a part of the main beachfill contract.”

Krys Johnson, spokeswoman for the city, said pre-construction meetings are planned, but no dates have been set.

Cooper said the new outfalls will have a more robust design better able to withstand storm damage, with steel pipe for added strength and an enhanced support structure around the pipe.

The corps is planning to begin work in late-November, pumping 424,000 cubic yards of sand on Rehoboth Beach and Dewey Beach. In a break from previous beach replenishment projects, the corps will use a new borrow site off Delaware Seashore State Park. The last beach repair in 2013 used sand from a site off Fenwick Island; the corps has changed sites to reduce the costs of moving the sand to the project beaches.

Meanwhile, Rehoboth Beach’s largest civic project, the wastewater ocean outfall, will be subject to a public hearing on five permits related to design.

The hearing will be held at 6 p.m., Tuesday, Nov. 15, at Rehoboth Elementary School.

The city is seeking five permits related to the $52.5 million ocean outfall project, including permits to install a 24-inch pipe in the ocean and conduct upgrades to the city’s wastewater treatment plant. A decision on the permits is expected by early next year.

Rehoboth is planning to build a force main to discharge its treated effluent at an outfall pipe located 6,000 feet off Deauville Beach, at the city’s north end. Rehoboth officials hope to complete the project by April 2018.

The hearing will take comments from the public with priority given to pre-registered speakers followed by speakers who sign up at the hearing. Speakers will have a five-minute time limit.

To preregister, email DNREC at Rehoboth_Wastewater_Comments@state.de.us or by mail to John Schneider, DNREC, State Street Commons, 100 W. Water St., Suite 10B, Dover, DE 19904. Anyone who cannot attend the Nov. 15 public hearing may submit comments to the above addresses by Friday, Dec. 2. DNREC prefers comments to be sent in via email.

For more information on the proposed outfall project, visit www.dnrec.delaware.gov/Admin/Pages/Rehoboth-Wastewater-Projects-Info.aspx.

• A National Pollution Discharge Elimination Permit authorizing the city to discharge treated effluent from its wastewater treatment plant. The permit would allow the city to discharge the effluent into the Atlantic Ocean at a site one mile off the coast of Deauville Beach. Also included are improvements to the plant itself, including new sediment-filtering screens and a sludge-removal facility.
• A subaqueous lands lease permit to install the 24-inch diameter outfall pipe in the ocean.
• A water quality certification required for dredging the ocean floor to install the diffuser at the end of the outfall pipe. The diffuser is a large, sprinkler-like contraption that disperses the treated effluent water into the ocean.
• A wastewater facilities construction permit to build a 3.5 million gallon-per day pump station at the treatment plant, as well as the force main and diffuser pipe to take the treated effluent from the plant to the ocean.
• A beach preservation coastal construction permit to drill the ocean outfall pipe. The city plans to directionally drill the pipe from the plant, along the Lewes-Rehoboth Canal, going under Grove Park and down Henlopen Avenue to Deauville Beach. The pipe will then be horizontally drilled into the sand to the diffuser site 6,000 feet off the coast.