March 29, 2024

Getting in compliance

City enters into engineering-services agreement with Veenstra and Kim for sanitary sewers

The city of Osceola has a problem with sanitary sewers, and it needs to get fixed.

During Tuesday night's Osceola City Council meeting, the council entered into a engineering-services agreement with Veenstra and Kimm for the old plant pumping station and force main sewer project that will take place on the south and west sides of the city.

"This is one of the projects that's in our facility plan that we completed for the city back in 2010, and it's also part of the consent-order agreement that the city signed back in 2010 with the DNR, as well," said Anthony J. Bellizzi with Veenstra and Kimm during the city-council meeting. "So, it's one of the requirements in our plan of action that needs to be completed to address the I and I (inflow and infiltration) issues and the sanitary-sewer overflows that the city has in the system."

Current problems

The project will replace the old pump station and force main. The issue with the existing pump station is it's not big enough to handle the flows of the service area that are tributary to it. It also receives some flows from three other pump stations via the crosstown-interceptor sewer when they are at peak capacity.

"It has, I believe, a capacity of somewhere in the order of 1.5 to 2 million gallons per day for that service area, and the flows that we see today, that needs to be closer to 5 to 6 million gallons per day, peak capacity," Bellizzi said. "It's well undersized."

He added, there's also issues with influent-meter structure and discharge location of the existing force main. The current force main is 8 inches and the location is in a place that won't be able to discharge in the future with the new force main.

"We've got another bypass downstream of that location, as well, so one of things we need to do is eliminate that force-main discharge at its current location," Bellizzi said. "So, you see on the drawing we provided, we've got a new route for that force main kind of along the westerly side of the Harkin Hills area down to the wastewater treatment facility. That's along an existing pipeline easement, too. … It kind of makes sense in terms of for future development on that ground we'd have an easement, most likely adjacent to it, or as close to that existing easement as we can get. So, not to disrupt future anticipated use of that property."

DNR compliance

Another issue the DNR recognized in August with a plant inspection is there's no standby power at the existing lift station, Bellizzi said.

"If we lose power, what that means is we're already bypassing flow during extreme-rain events at that lift station site," he said. "If we lose power, we'd be bypassing a lot more flow from that location. So, that's in their inspection report. They've asked the city to expedite those improvements, based on the consent order that's something that needs to be done by, I believe, 2015."

Time is of the essence to get the project improvements up to date. If the city doesn't make the improvements by 2015, the state will come in and enforce it.

"That clock is ticking right now," Bellizzi said.