ADDENDUM #2: Sonestown Sewer System Improvements

This Addendum consists of the following items:
Alteration to Scope of Work Section: Upon meeting with engineers at the Wednesday August 14th, Pre-Bid meeting, it was determined that the scope of work section of the RFQ was lacking directive for interested firms and that a more detailed scope of work would be required. This addendum shall replace the Project Description narratives pages 4 and 5 as well as page 14 which is the Standard Engineering Estimate.
Updated Scope of Work:
History of Problems of Collection System:
Davidson Township Sewer Authority provides wastewater and sewage treatment for the Village of Sonestown in Sullivan County. The Village of Sonestown is in a rural area of Sullivan County and has about 200 residents. There is one hotel and restaurant, a guest house, Thermal Blade business, gas station, and convenience store. The village has no access to public water supplies. The residents and businesses use wells for their drinking water and have a failing sewer system that has severe deficiencies.
The current system is a gravity fed system that utilizes settling tanks located on private properties that are pumped periodically pumped. The water table in Sonestown is located close to the surface which causes a problem with the settling tanks being buoyant. Without anti-buoyancy ballasts in each of the settling tanks, the tanks continue to be displaced and "pop up" during high water events. Sewer backups have previously caused an overflow of raw sewage into people's yards and into the streets. The collection system also lacks access points to flush and clean out clogged lines, which increases the chances of system backup and environmental spills that impact the health of the residence and the environment. There are also concerns that the gravity fed pipes have settled and cause increased buildup that increases the inefficiency in the system.
The Village of Sonestown sits along Muncy Creek and has experienced many high-water events that have caused an overflow of sewage due to cracks and breaks in the gravity line. Sewage back-ups have happened in the past and will continue to occur, contaminating ground-water supplies. Sewer back-ups occur when the system is overloaded, threatening the entire community's health.
This deteriorating system creates a dangerous situation and leads to a breeding ground for viruses and bacteria. These occurrences of contamination are a serious threat to the health and safety of Sonestown's residents.
History of Problems of the Wastewater Treatment Plant:
The system has a number of concerns and issues that have made major improvements to the system necessary. Specifically, the chlorine contact pit is open to the air and not protected from contamination. The current Sand Distribution System experiences clogging and bio-growth in the distribution piping that does not allow the wastewater to distribute evenly throughout the surface of the sand filters, which causes wastewater concentration. The main line from the pump station along with the solids collection tank have settled and wastewater discharge has resulted in the area. The current power control panels do not operate correctly, and the booster pump operation panel is exposed to the elements. Lastly, the effluent piping from the treatment plant does not have a check valve that would stop any flow from entering the effluent discharge piping. The valves in the valve pit at the plant are manually operated; when the pit fills with water, the valves are not reachable, rendering them useless. Automatic actuators would allow an operator to switch between filter beds and pumps during operation without manually turning the valves in the pit. In addition to these issues, five pumps throughout the system and the trash pumps need to be replaced as they are inoperable or otherwise in poor condition.
The current treatment plant is not only failing but is also prone to flood events. The WWTP has historically been inundated by floodwaters every five years or so. During those events, the Davidson Township Authority has had to manually operate the plant. Along with the flooding events the plant itself has severe deficiencies that need to be addressed, with its drainage bed requiring a new liner with new sand and stone to better treat the sewage entering the plant. The irrigation pipes also have several problems which include being clogged, brittle, and settling, not allowing for even distribution of liquids. These deficiencies have caused the plant not to function as efficiently and have compounded the problems faced by Sonestown and its residents.
Phase I Work Completed on Collection System:
In 2023, Phase I of the Sonestown Sewer System Improvements was completed this included the replacement of pumps at the main street pumping station. As well as rewiring these pumps to protect the wiring from the elements. There was also an alteration made to the collection system where surface water was entering the collection system and contributing to overwhelming the system.
Phase I Work Completed at Wastewater Treatment Plant:
Along with the work done to the collection system the pumps located at the plant were also replaced and rewired to increase the efficiency of the plant and its ability to process wastewater. Along with pump replacement the control panels located in the plant office were also replaced. A total of five pumps were replaced across the system and WWTP as well as most of the electrical equipment used to operate the system as whole.
Other improvements were put aside because of funding and time restraints.
Phase I Engineering Recommendations for Collection System and differing Recommendation from Pre-Bid-Meeting:
The original plan for Phase II of the Sonestown Sewer System project was to address conveyance issues in the collection system. The engineer believed that if the existing settling tanks are to be used, grinder pumps will need to be installed in each tank. The collection system scope of work in this project may include the complete installation of the following:
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Existing lines will need to be filmed and analyzed.
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The conversion of select sections from gravity drains to low pressure sewer lines.
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Installation of grinder pumps in each tank in the south system.
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The connection of laterals to grinder pumps and the low-pressure sewer main.
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Tank modifications to convert to the tanks for use of grinder pumps.
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Ballast in tank to reduce volume and provide flood protection.
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Connect users in Swamp Poodle Road to existing pump station located on Main Street.
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Convert the force main located on Swamp Poodle Road to a low-pressure sewer system.
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Install grinder pumps in tanks in the north system.
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Tank modifications to convert the tanks for the use of grinder pumps in the north system.
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Place ballast in tanks to reduce the volume and provide flood protection.
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Upsize gravity line through baseball field to 8” sanitary sewer with manholes.
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Convert north system to lower pressure sewer system.
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Connect all grinder pumps to the lower pressure sewer system.
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Convert gravity drain through baseball field to a low-pressure sewer system.
Upon meeting with other engineers at the Pre-Bid meeting on August 14, 2024. The following alternatives were provided.
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Maintain a gravity system instead of converting to low pressure system.
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Evaluate current pipes in Collection System through videoing.
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Plan to correct or replace pipes that have settled or broken to restore flow. The extent of rehabilitation and replacement work is unknown at this time.
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Evaluate settling tanks for deficiencies and stabilize them for continued use.
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Evaluate the Main Street pump station and update any equipment that needs to be replaced.
Phase I Engineering Recommendations for Wastewater Treatment Plant and differing Recommendation from Pre-Bid-Meeting:
The original engineer on Phase I advocated for a new package treatment plant. The new treatment plant would provide advanced wastewater treatment and needs to be safe from the risk of flooding during high-water events.
Upon meeting with other engineers at the Pre-Bid meeting on August 14, 2024. The following alternatives were provided.
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Staying with a gravity system would mean that the existing plant could be kept in place and existing structures replaced to make the plant more efficient.
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This could include replacing drainage beds with new liners and filtering materials such as sand and stone replacement.
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Replacing valves to adjust flow rates to the beds to better control the plants operating process.
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Install an improved dichlorination system to make the plant more efficient.
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Also flood mitigation measures which could include an installation of flood walls around the plant to protect from flooding events.
It is expected that the retained engineer will need to provide the most advantage and economical solution, that will provide Sonestown with a fully functional sewer system for the future.
An Act 537 amendment to the Authority’s existing plan for the collection line and/or WWTP improvement, may be needed depending on the initial recommendations of the retained engineer.
Sullivan County has obtained CDBG funds for this project in the amount of $1,023,204.00, these funds will include engineering costs. Additional funds may be added to the project at the discretion of Sullivan County or Davidson Township. Bidding for the project may have to be conducted at different phases and at different times frames depending on time constraints established by the funding sources.