“These elements comprise parts of the City’s infrastructure that are largely unseen and un-noticed by the public…until they fail,” Milliman noted. “Our sewer collection and wastewater treatment system is substantial, with many stationary and moving pieces that are expensive to maintain.”
The $133,825 sewer rehabilitation project on Pacific and Mendy Streets is complete. This project involved lining some 1,400 lineal feet of older sewer main and replacing 25 sewer service laterals. The goal of the project is to eliminate the intrusion of storm water into the sewer collection system. Storm water intrusion results in overloading the collection system and unnecessary costs associated with treating storm water through the wastewater treatment plant. Similar projects are being planned in other parts of town. John Rapreager, of Brookings, was the contractor for this project.
Two of the City’s sewer lift stations, Macklyn Cove and Dawson Tract #1, required emergency repairs. Macklyn Cove’s lift station discharge piping suffered severe corrosion which resulted in pump failure. While the extent of needed repairs was being evaluated, the lift station was disabled and drained regularly by Roto Rooter service. Repairs were completed at a cost of $7,000 in addition to the $8,210 in emergency pump-out costs.
A section of pipe located beneath the Dawson #1 lift station failed, causing the lift station to malfunction. The $40,000 emergency repair project required shoring and excavation under the lift station building. A geotechnical engineer was retained to develop foundation support recommendations for the building before repair work could begin. “This was a small but very difficult project because of the tight site conditions and the need to maintain the lift station in operating condition,” Milliman said. Additional work needed to complete this project includes pile drive stabilization for the building.
A $19,000 project to replace failed air piping at the Wastewater Treatment Plant (WWTP) is scheduled to begin within two weeks. The contractor for this project is Martin Glazebrook, of Brookings.
Wastewater processed through the WWTP receives ultraviolet (UV) disinfection before it is discharged to the ocean. The UV system at the WWTP has experienced several malfunctions and replacement of worn-out parts is underway this week, with installation work primarily being performed by WWTP staff. The overall project cost is estimated at $208,000.
During a post-tsunami inspection of the ocean outfall from the WWTP, which extends some 500 feet into the ocean off Chetco Point, divers discovered several devices…known as diffusers… through which the treated wastewater is discharged, to be missing. Divers are scheduled to install replacement diffusers and improved fasteners at 10 locations along the outfall line this week. This $5,300 project has been contracted to Ballard Diving and Salvage, of Seattle, WA.
Also at the WWTP, the City has installed a new device…known as a “macerator”…that is used for grinding sludge particles at the end of the treatment process. The total cost for this project was $20,251.
Public Works and Development Services Director Loree Pryce is responsible for overall management of all of the above listed projects. Questions can be directed to Pryce at (541) 469-1138.