Dredging

February 2016

From the Leader-Telegram:

ALTOONA – On Friday afternoon Lake Altoona looked just like normal, its mostly calm surface sparkling as it reflected the sunlight and bright blue sky above. 

But two portions of the lake – the delta where the Eau Claire River enters the body of water and the spot where Five Mile Creek flows in – have significantly less sand, thanks to dredging in February and March.

In recent years those lake entries had become clogged with sand pushed there by the river and creek. As the lake filled with sand at those points, boat travel became difficult.  

Sediment filling portions of Lake Altoona has been an ongoing problem in recent decades and has necessitated periodic dredging of those areas. Past hydraulic dredgings have proven costly for the 300-plus residents who live near the lake and are part of a lake district.

When district chairman Paul Johnson learned the lake would be drawn down 9 feet during the winter for repairs to the Lake Altoona dam, he figured it would be a good time for a different, cheaper type of dredging. On Feb. 3 the lake district board approved spending $1.14 million to remove sand from portions of the lake with heavy equipment, a process made possible by the lake drawdown. 

Knowing the lake would be refilled in late March, lake district officials sought a reduction in the normal permitting process from 150 to 60 days, a move that won the approval of state Department of Natural Resources and Eau Claire County officials. 

Johnson praised the work of the DNR and county, adding “without the quick action of the property owners of Lake Altoona, this project would not have been completed.”

Haas & Sons of Thorp began removing sediment on Feb. 15 and lake district officials hoped the weather would cooperate to allow for sediment removal. It did, and the work was finished on March 8. 

“We were thrilled to see how quickly Haas & Sons were able to finish this project,” Johnson said.

The areas dredged average 3 to 4 feet deeper than they were. In all 214,000 cubic yards of sediment was removed from the lake, at a cost of $4.82 per yard removed. Removing sediment hydraulically would have cost between $16 and $20 per yard, Johnson said, and he estimates the ability to dredge while the lake was drawn down reduced project costs by nearly $3 million. 

“Having that lake drawn down turned out to be a big break for us,” Johnson said. 

In another bit of good news, the project cost $1.03 million, or $103,916 less than budgeted. In fact, lake district board members, DNR and county officials are so pleased with the project they hope to use it as a blueprint for similar efforts.

“This sets a precedent for successful cooperation between these organizations in the future,” Johnson said. 

The lake was most recently dredged during a couple of years beginning in 2008. Prior to that dredging occurred in 1996. Lake district residents are about to pay off the last dredging and will maintain annual $175,000 payments to fund the recently completed dredge through 2026. 

Video of dredging