Posted on June 9, 2016
By Dana Larsen, Pilot-Tribune
Downtime and maintenance expense on the lake dredge are growing costly, without much production being seen for the money so far this season.
Currently dredging is at a standstill due to problems with the heat exchangers on the dredge boat. Only two full days of dredging have been done to date this season, and work is not expected to begin again until next week.
Local officials are in discussion with the contractor, Dredge America, on what to do about the lost time. The company is paid by the amount of silt removed, but the City is responsible for dredge maintenance, so will likely have to pay the company for time its crew is standing by unable to work.
City Manager Jim Patrick and Lake Improvement Commission leader Gary Lalone have met with the Iowa Department of Natural Resources about the future of the project.
While the community is committed to dredging over the next one or two more years, a decision will have to be made comparing dredge operations to the recommendations to the Fyra Report, in which an Omaha engineering company suggest using aluminum sulfate and engineered breakwater construction in the lake instead to deal with the turbidity issues.
“What will be the bigger bang for the buck? Yes, we have our new spoil site, but do we really have to fill it at this point?” Patrick asks.
One possibility is ceasing dredging but retaining the spoil site, which may be needed to hold material if breakwaters are constructed in the lake. “In reality it is the last place we have” in proximity to the lake, Patrick said of the spoil site.
The dredge was purchased used by the county for $450,000. It was rebuilt about 10 years ago, but significant maintenance issues have plagued the project in recent years, including a couple of incidents of leaking oil spilling into the lake this spring.
The heat exchangers, a system that uses lake water to cool hydraulic fluid pumping through tubes, are the current problem. They have failed, been fixed, and failed again.
The dredge and related equipment was recently appraised at $1.2 million, and selling it is an option. That decision would have to involve the LIC, Patrick said.
The dredging project remains worthwhile, he adds. “We’re deepening the lake, and I think we’re still making progress. But alum treatments and wave breaks may be more beneficial at this point.”
The IDNR, City and LIC will continue discussions this summer toward a plan for the future of lake improvements. Local officials are also asking the DNR to consider increasing funding to the project.dred
The LIC has about $720,000 remaining in its dredging fund. A full season of dredging could cost as much as $750,000 under the contract with Dredge America, which does not include the price of the dredge repairs.
SOURCE: Pilot-Tribune
