FAQs – Wastewater-Implementation of Ocean Outfall Alternative Discharge

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  • Why is the City undertaking this project?

    In 1998 the Delaware Department of Natural Resources and Environmental Control (DNREC) adopted a regulation for the Inland Bays known as a Total Maximum Daily Load (TMDL). The TMDL identified the nutrients nitrogen and phosphorus as impairing the Inland Bays and ordered reductions of these nutrients entering the bays. The treated wastewater from our wastewater treatment plant contains relatively low levels of these nutrients, however, the TMDL requires the complete removal of the City’s nutrients from the Inland Bays Watershed.

  • What is included in this project?

    There are five elements to this project:
     
    ·         An ocean outfall that will discharge the City’s highly treated wastewater over one mile from the shore.
    ·         A new effluent pumping station within the site limits of the existing RBWWTP.
    ·         A force main running north from the RBWWTP along the edge of canal, in Right of Way of USACE Lewes-Rehoboth Canal, along Roosevelt Street to DE-1B, under Rt. 1 Bridge, to State Road to Canal Street, under Rehoboth Avenue and Grove Park, and in Right of Way of Henlopen Avenue to the Deauville Beach parking area.
    ·         Treatment plant improvements and reliability upgrades.
    ·         Changing the disposal of bio solids (treated sewage sludge that meets EPA requirements) generated at the treatment plant from land application of Class B to drying as Class A.

  • Why was an ocean outfall selected to comply with the TMDL?

    In 2002 the City signed a consent order with the State, entered in the Delaware Superior Court, agreeing to study effluent disposal alternative and implement the selected alternative. The City investigated four possible alternatives; ocean outfall, spray irrigation, rapid infiltration beds and deep well injection. After exhaustive studies by experts, along with presentations and public hearings, the Commissioners unanimously selected ocean outfall as the best option to meet the TMDL. In January 2015 DNREC concurred with the City’s assessment that ocean outfall is the most environmentally and financially responsible alternative when the Secretary of DNREC issued the Record of Decision DNREC stated “Specifically, the ocean outfall is the only alternative that assures 100 percent of nutrients from the Rehoboth treatment plant are eliminated from the Inland Bays watershed. Any land application alternative – including constructed artificial wetlands, would result in wastewater discharges to either ground or surface waters, continuing to add nutrients to the Inland Bays. Likewise, locating a treatment facility in the adjacent Broadkill River watershed would also continue to add nutrients to a system already impaired by nitrogen and phosphorous.”

  • How will this project be financed?

    The City currently has commitments from the Clean Water State Revolving Fund to finance the outfall and plant improvements at an interest rate of 2% and for terms of 25 and 20 years respectively. The City has a loan from the same source with an interest rate of 2%.

  • Will other jurisdictions share in the cost?

    Yes. The City treats all the wastewater generated east of the Lewes-Rehoboth Canal. The City contracts with Sussex County to treat the wastewater from their Dewey Beach and Henlopen Acres districts. The City does the collection and treatment for North Shores and bills the customers directly. The recent flow data is:
     
    ·         55% Rehoboth Beach
    ·         36% Dewey Beach
    ·         4% Henlopen Acres Sanitary District
    ·         5% North Shores
     
    Rehoboth Beach will ultimately only have to pay 55% of the cost, or a little over $28.8 million. The other communities served by the wastewater facility will ultimately pay 45% of the cost of the project, or $23.6 million.

  • Why is the City borrowing all of the money?

    The City owns the wastewater treatment plant. In order to control the schedule and avoid delays it was decided the City would borrow all necessary funds. The City will recover from the other entities their proportionate principal and interest payments through periodic billing.

  • What will be the effect on user rates?

    It is estimated that the average residential customer will pay about $760 per year for wastewater service once the project is complete. This amounts to a little over $2.00 per day. This compares to an average of $325 today not including the current sewer surcharge of $488 if the surcharge is included.

  • Did the City investigate with a privately owned utility?

    Yes. In 2008 as the City was investigating its options to eliminate and canal discharge, Tidewater Utilities and Artesian Resources expressed interest. The City took the time and incurred the expense to prepare and advertise a Request for Proposals. The RFP specified spray irrigation as the disposal method. Once the RFP had been issued Tidewater Utilities wrote a letter requesting that the City also accept rapid infiltration basins (RIB) as the disposal method. The City sought the State’s assistance in responding to Tidewater Utilities Request. DNREC responded that they consistently opposed the use of RIB’s to dispose of the City’s wastewater. Only one submission was received in response to the RFP. It was from Artesian but could not be evaluated because it proposed an unworkable concept and contained no pricing.

  • What are the plant improvements and reliability upgrades?

    The original facility was constructed in 1935. There were complete upgrades for biological nutrient removal in 1959, 1987 and 1994. The current treatment plant went into operation in November 1987. Since then the plant has operated 24 hours a day and seven days a week. It is now time to replace many of the pumps and mechanical equipment; replace the roofs on the buildings; paint the various steel structures; replace the final effluent filters with ones of newer design and easier operation. The main electrical switch gear will be replaced and a generator will be installed that can power the treatment plant in the event of a power failure. The City has been holding off on this work waiting until the effluent disposal issue is resolved.

  • What DNREC permits are required to construct and operate the ocean outfall?

    1. National Pollutant Discharge Elimination System (NPDES) Permit
    2. Coastal Zone Management Act Federal Consistency Determination
    3. Subaqueous Lands Act Permit
    4. Water Quality Certification
    5. Wastewater Facilities Construction Permit
    6. Beach Preservation Coastal Construction Permit

    The City also needs a permit from the U.S. Army Corps of Engineers, a sediment and stormwater permit from the Sussex Conservation District, and DelDOT permits for work on State road right-of-ways.

  • How will the DNREC permits protect the environment and the health of beachgoers?

    There will be numerous restrictions and requirements to ensure that water quality, aquatic life, and swimmer health are protected. During construction, impacts to the dunes, beach and nearshore ocean will be avoided by installing the outfall pipe using horizontal directional drilling (HDD) techniques. This is the same technique used to install various utilities like water lines, sewer lines, electrical cables, and communications cables beneath roads, streams, driveways, and other infrastructure that is impossible or costly to displace. The outfall pipe will be split into two installation methods, HDD and open-cut marine trench and cover. At a minimum, the outfall pipe will be installed via HDD a minimum of 3,000 LF offshore. At that point, the outfall pipe will be installed via open-cut marine trench excavation and cover, the remaining distance, for a total of 6,000 feet, and terminate with a diffuser assembly. Permits will restrict all of the ocean work to the colder months when piping plovers, ospreys, migrating fish, turtles, and mammals are not in the area to avoid impacts to marine species. Further, construction of the outfall during the off-season will minimize disruption of recreational uses of Deauville Beach, the parking area, tennis courts, and avoid traffic delays during the busy summer season. Should there be any unavoidable impact to the dunes, restoration and revegetation will be required. Additionally, if there is a threat of coastal storm or higher than usual tides, any pipe or equipment will be moved to avoid impacts.

    When the outfall is operational, the National Pollutant Discharge Elimination System (NPDES) Permit will ensure that water quality and swimmers, surfers, and other users are protected. The permit will include numerous effluent limits and monitoring requirements including but not limited to bacteria, dissolved oxygen, pH, biological oxygen demand, and total suspended solids. With respect to nitrogen and phosphorus, the City of Rehoboth Beach will be required to maintain the current treatment and effluent quality.

    Additionally, the Subaqueous Lands Act Permit will require the monitoring of benthos (marine bottom-dwelling organisms) before construction begins and at least two years after construction of the outfall is completed. These organisms are ecologically important and serve as sources of food for animals such as the Atlantic Sturgeon and Shortnose Sturgeon; both listed as endangered under the federal Endangered Species Act.
     

  • When will the outfall be constructed?

    The schedule calls for work to begin in October 2017 and for the outfall to be operational by June 1, 2018.

  • Why is the City changing from Class B to Class A bio solids?

    Bio solids are the nutrient-rich organic by-product of domestic wastewater treatment. The City currently disposes of the bio solids generated at the treatment plant by trucking them to a farm field north of Milton, where they are injected into the ground. The product is only about 2% solids with the remainder being water. Currently the bio solids are classified as Class B, which have additional management practices due to the less complete pathogen reduction levels and the disposal site must be permitted. Class A bio solids are viewed as an asset. Since Class A bio solids have reduced pathogen levels, Class A bio solids can be used as a fertilizer, soil amendment, or composting blend on residential lawns, gardens and parks where unrestricted public contact is likely.

  • What does “effluent” mean?

    “Effluent” means treated municipal wastewater.

  • How much water comes out of the outfall?

    The current plant peak weekly flow varies. During the summer months the flow is around 2,000,000 gallons per day and tapers off during the winter months. That is total volume in a 24 hour period.

  • Who can I contact to get information about the Ocean Outfall Project?

    For more information about the project, please contact the Communications Department at 302-227-2772 or email [email protected].

Stay Informed!