Wastewater Ocean Outfall

PDF icon Ocean Outfall Town Hall Presentation Sept. 16, 2017The City of Rehoboth Beach is required, under the terms of a consent order from the Dept. of Natural Resources, to eliminate the discharge of treated effluent from the Rehoboth Beach Wastewater Treatment Plant into the Lewes-Rehoboth Canal. The city, after detailed studies and the evaluation of all options, is proposing an ocean outfall in order to comply with that order.

Wastewater Outfall pathThis project consists of a new pump station and a 24 inch force main/pipe which are required to convey the treated effluent to the ocean outfall and to provide the head required to pump the effluent through diffusers located 6,000 feet offshore in water approximately 40 feet deep. Vertical turbine effluent pumps will be installed in the existing post-aeration tank. The force main will be aligned along the plant access road and end at the public access parking area at the beach near Henlopen Avenue.

The pipeline from the Rehoboth Beach Wastewater Treatment Plant to the ocean outfall was sized to handle the summer peak flow. As part of the overall project analysis, a detailed alignment study was completed to determine the best routing of the force main considering such issues as cost, environmental issues, permitting, potential interferences, traffic control and public concerns. The preferred alignment was selected based on the recommendations of the Rehoboth Beach Wastewater Treatment Plant Effluent Force Main Alignment Study.

Project Update 

Drone video of the ocean outfall diffuser towed from Lewes to Rehoboth and placed on the ocean floor. 

Please visit our YouTube channel for more videos at https://www.youtube.com/c/rehobothbeach


The crew is now at Canal Street working towards Rehoboth Avenue. This section of work is expected to take two weeks. They have installed a total of 4,478 LF of pipe to a point beyond the intersection of DE-1B and Canal Street. Tracer wire and metallic ID tape were installed along the entire alignment. Backfilling and compaction were performed daily. The jack and bore subcontractor continues installation of the 36” casing, 60 LF of casing was installed last week. The contractor will not be working this Saturday. Canal Street from Sixth Street to Rehoboth Avenue remains closed. Access to Canal Street is for local homeowners only. All work is weather dependent.

The contractor is working on Henlopen Avenue between Third Street and Gerar Street. This section of work is expected to take two weeks. Sewer and water service laterals continue to be reconnected as necessary. The crew has installed from Deauville Beach 2,277 LF of pipe ending 180 ft. before Third Street. All work is weather dependent.

PDF icon Force Main Lookahead Schedule


The horizontal directional drilling contractor has two shifts working at Deauville Beach 24 hours per day, seven days a week. The contractor continues installation of pipe casing in the drilled hole. The current schedule this weekend is the contractor will tow pipe from Lewes to offshore. Divers will connect pipe to the drill string and pipe pullback is estimated to be completed in one day. Offshore activity is anticipated to continue mid-week installing concrete mats. The Deauville Beach parking area continues to be closed to the general public. Access to the tennis courts is from Surf Avenue.  

 PDF icon Ocean Outfall Three Week Lookahead Schedule


  • The force main contractor will notify property owners on-site a week before and the day before work is nearing your home. We will also keep you updated with construction schedules via email as they become available. The contractor is required to maintain access, water, electric, and sewer service to all properties during construction. However, there will be a temporary 6-hour water and sewer shut off while work is being performed in front of your property. Residents adjacent to the construction area may experience short periods when crews will need to limit driveway access. We will work closely with those affected and provide as much advance notice as possible.  
  • Only the disturbed areas on both sides of Henlopen Avenue will be replaced with stone. If the contractor or the city finds it necessary to remove pavers, plants, etc., on city property for project work, they will remove the items and place them aside on your property. The contractor or city will not replace items in the right-of-way. You are responsible for reinstalling your items in the same area from which they were removed, however, with the awareness that it is city property where future decisions of the commissioners could alter these permissions. 
  • The contractor will work to ensure disruptions are minimized during construction operations and will restore all work sites to their original condition as quickly as possible. 
  • All traffic will be maintained around construction zones. The contractor will utilize maintenance of traffic standards established by DelDOT for traffic control, including signage and protective barriers that will be set up to maintain public safety during construction. Traffic impacts will be minimized as much as possible, however, please plan for some delays and travel carefully through the work zone.  
  • Provisions will be made to ensure that the contractor allows refuse pickup, mail and delivery service to be maintained during the force main project. 
  • Selected trees within the force main work zone limit of disturbance along Canal Street and Grove Park were flagged and removed.
  • The force main contractor working hours are Monday through Friday from 7 am to 6 pm. The ocean outfall contractor working hours are seven days a week, 24 hours a day, at Deauville Beach. Marine work is seven days a week, 24 hours a day.    
  • Construction completion:  Ocean Outfall April 2018 – Force Main May 2018


The contractor is continuing installation of the FRP accessories, including the launder covers, density current baffles and scum baffles in the Clarifier T3-A. The contractor has also started working on preparing the anchors for the center column and seal plate. In the Filter Building B2, electrical installation, including the installation of the interior lighting and emergency fixtures conduit on the upper level and pulling wires between the lighting fixtures and the lighting control panel continues. The contractor has poured the roof slab of the wet well in the effluent pumping station. The structure is now 100% complete. Backfilling has progressed, and is now 95% complete. The electrical contractor has moved onto the construction of the third ductbank, RTU-3, starting excavation, and installation of reinforcement steel and conduit

Please contact the Communications Department at 302-227-6181 ext. 522 or [email protected] for additional project information or questions. 

New skylight at the WWTP

On August 14, 2017, the Rehoboth Beach Commissioners unanimously approved awarding four bid packages to various contractors to begin construction on the ocean outfall project. The project consists of a new pump station and 24-inch force main, which are required to convey the treated effluent to the ocean outfall and to provide the head required to pump the effluent through diffusers located 6,000 feet offshore in water approximately 40 feet deep. The bids totaled $37,381,407. The ocean outfall bid was awarded to Manson Construction of Seattle, Washington, for $27,655,850. Allan Myers Construction of Worcester, Pennsylvania, was awarded the effluent pumping station bid for $1,768,555, and the wastewater treatment plant upgrades for $2,256,555. A-Del Construction of Newark, Delaware, won the force main bid for $5,700,447. Contractors were pre-qualified by GHD, the engineering company for the project. Steps taken to pre-qualify were assessing each contractor's project completion record, reviewing their performance on similar projects, safety record, insurance coverage and other factors. Mobilization of equipment will tentatively begin October 1, 2017, and work is to be completed by April 30, 2018.

On August 7, 2017, the Rehoboth Beach Commissioners unanimously approved a renewed and expanded Agreement for Wastewater & Biosolids Services with Sussex County. Sussex County Council unanimously approved the PDF icon Agreement for Wastewater & Biosolids Services at their meeting on August 8, 2017. Under the new agreement, the county will continue to pay the city to treat wastewater from surrounding areas of the county's sewer system. The county will be responsible for hauling via truck the city's biosolids to a new treatment plant at the county's Inland Bays facility. Fees will be determined once the new facility is operational, and the city will not have to contribute to operating costs until that time. Sussex County's contribution toward the $52.5 million outfall project will be based on utilization of services.

Announcement of Rehoboth Beach issuance of outfall permitting

On May 25, 2017, Delaware Department of Natural Resources and Environmental Control (DNREC) Secretary Shawn M. Garvin approved and signed the Secretary’s Order for the Rehoboth Beach ocean outfall which includes all required DNREC permits to move forward with construction. The U.S. Army Corps of Engineers will be issuing a permit along with a Sediment and Stormwater Permit from the Sussex Conservation District, and DelDOT permits for work on state road right-of-ways.

The approved pipeline alignment begins at the existing Rehoboth Beach Wastewater Treatment Plant, follows the Lewes and Rehoboth Canal north to Grove Park. The pipeline will then turn northeast to Henlopen Avenue and continue along Henlopen Avenue to the Deauville Beach parking area and terminate in the Atlantic Ocean, approximately 6,000 feet from the parking area. The 24-inch high-density polyethylene (HDPE) pipeline will be installed via horizontal direction drill approximately 3,000 feet and marine open-cut trench approximately 3,000 feet. Once the pipe is anchored in place with concrete collars, the open-cut trench will be backfilled. The terminus of the outfall pipe will consist of a 120 linear foot diffuser comprised of eight risers, 1.5 feet above the ocean floor, with four discharge ports per riser. The diffuser will be installed on pilings to ensure stability. Mobilization of equipment will tentatively begin October 1, 2017, and work is to be completed by April 30, 2018.

The Secretary's Order can be viewed at http://www.dnrec.delaware.gov/Info/Pages/SecOrders_Permits.aspx

Change Orders

Approved Permits

Bid Information

Contract Information

DNREC Workshop & Hearing

DNREC Public Workshop October 19, 2016
DNREC Public Hearing November 15, 2016

Frequently Asked Questions

FAQs regarding the Wastewater-Implementation of Ocean Outfall Alternative Discharge




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