- Nassau County Department of Public Works
- East Rockaway, New York
- Our Role
- Design, Construction Administration, Inspection, Construction Management, Training, Staffing, Facility Start-up, Technology Investigation, Site Survey, Construction Estimating, Contract Drawings.
- 70 mgd
- Construction Cost
- $20 million
- In Progress
- Increased the plant's capacity and efficiency to meet community needs
- Improved effluent screening system safety
- Improved the effectiveness of the effluent strainers.
The Bay Park Sewage Treatment Plant was constructed in 1949, with major expansions and upgrades during the 1960s and 1980s. The current permitted capacity is 70 mgd, although current average daily wastewater flow is 50 mgd. The plant serves a population of approximately 550,000.
The Nassau County Department of Public Works (NCDPW) identified problem areas at the Bay Park Sewage Treatment Plant that restrict the plant's operational flexibility and prevent it from operating at peak efficiency. These problem areas included the hot- and chilled-water distribution system, grit removal, effluent screening, effluent pumps, process air filtration, emergency generators, and dissolved air flotation thickeners.
Our firm assisted in the preparation of a technical design report identifying the best strategies to deal with the problem areas while providing for maintenance of plant operations. After approval of the technical design report, our firm assisted in the design, contract preparation, inspection services, and operations and maintenance phases. Gannett Fleming evaluated deteriorated and leaking portions of the Bay Park sewage treatment plant’s hot- and chilled-water distribution system to determine whether the system needed to be replaced. The evaluation was critical in preventing a potential system failure that could have impacted plant operations and treatment processes. Portions of the underground piping were significantly deteriorated, resulting in leaks, leaking valves, metallic piping corrosion, and infiltration of groundwater into the piping insulation and jacket. As a result of the evaluation, our firm proposed replacing the hot- and chilled-water distribution system with a new state-of-the-art piping system. Our firm is providing construction assistance to oversee tasks and to verify that work is completed in accordance with the contract documents.
Gannett Fleming reviewed the operation of the effluent traveling screens pump system and its related effluent water reuse system. The effluent traveling screens pump system restricted the plant’s operational flexibility and prevented it from operating at peak efficiency. Our firm proposed and designed changes to the system, including effluent strainer upgrades, a new force main, effluent pump platforms, and controls to tie sump operation in with effluent traveling screen and effluent strainers operation. Additionally, we are currently providing design and construction-administration services for the rehabilitation of the grit-removal facility. Previously, it was concluded that rehabilitating the three existing detritor tanks was the most economical approach; however, we evaluated other available grit-removal technologies, and proposed the construction of vortex grit chambers within the existing detritus tanks. This proven technology offers consistent removal efficiency over a wide flow range. Our firm is also providing the heating, ventilation, and air-conditioning (HVAC) design and general inspection services for the grit-removal equipment.
- Technology and plant facilities evaluation and investigation
- Prepared detailed plans, specifications, and drawings to define the mechanical, civil, and geotechnical elements of the project; plans were suitable for use in obtaining contractor bids
- Construction-phase services, including attending a pre-bid meeting, site visits during critical phases of the construction, general inspection services, and construction monitoring
- HVAC design, including an odor control system
- General inspection services for grit-removal equipment
- Assisted in updating the pertinent sections of the existing Bay Park Operation and Maintenance Manual
- Facility start-up, staffing, and training services.