Scappoose stares down $20.5 million in sewer upgrades
Improvements and upgrades to the wastewater system in Scappoose are estimated to cost $20.5 million over the next 20 years.
Engineers with water consulting firm Carollo Engineers updated the Scappoose City Council Monday evening during a workshop to lay out a timetable of needed capital improvements and cost estimates for each phase.
The cost is daunting, but the projects are necessary, engineers and city staff say, to keep the Scappoose sewer system working efficiently and to keep up with growth over the next two decades.
"We've got development happening, it's happened, we're going to be seeing more coming soon," Scapppoose Mayor Scott Burge noted. "It's good but we need to make sure we're continuing to move forward on this."
"It's not really a high-tech treatment plant you have now," Bob Eimstad, a principal with Carollo, told the council, noting a system that allowed for around-the-clock remote monitoring would be ideal.
City Manager Michael Sykes said when the same wastewater project was priced out by a different company a year ago, the city was given a $43 million cost estimate. The high cost brought a halt to the project until the estimate from Carollo was received.
Within the city's urban growth boundary, it's estimated the region will see a 56 percent growth rate. That means the city will have many more households and businesses to serve and hook into the wastewater system. The growth bodes well for the city, as fees paid by new development will help generate revenue for capital projects.
When asked how Scappoose stacked up to other cities faced with tackling major wastewater infrastructure projects, Carollo staff said the city was likely in a better position to pay for the upgrades it will need.
"I think a lot of communities are facing similar challenges," Bhargavi Ambadkar of Carollo told city councilors and staff. Ambadkar noted in Klamath Falls, which has a higher population than Scappoose and is staring down roughly $35 million worth of projects, the estimated growth rate is only 5 percent.
What's needed, in phases
An analysis of the city's existing system shows the city's pumping stations, UV disinfection sites, and other components of the treatment processes contain "severe leaks," as well as aging pumps, a heating and cooling system that's not up to code, and other mechanical failures throughout the system that need to be addressed. The process for treating solids within the system is also undersized, a report shows.
To address inadequacies in the system, projects are being planned in phases.
Immediate improvements, which are slated for sometime between 2018 and 2019, include a lift station at Spring Lake, a new UV disinfection operation and aerobic digester, estimated to cost $1.32 million.
Phase I would likely happen between 2020 and 2022, to include influent pumping upgrades, as well as a second channel of UV disinfection, a new pumping station, and hydraulic and operational upgrades to the tune of $12.1 million.
Phase II comes with an estimated $4.6 million pricetag to pay for a secondary clarifier. That likely won't happen until 2026 or 2028.
Phase III, scheduled for 2033-35, includes the addition of another aerobic digester, could cost about $2.5 million.