Aren't you glad Fond du Lac will only be using well water?







Ahh the taste of fresh clean blue water free of lake sludge. Thank you Concilman Thiesfeldt and all who worked so hard to stop this project. I only wish former Concilman Mike Schmal could enjoy the taste difference.

Posted July 11, 2006 online Fond du Lac Reporter and Appleton Post-Crescent

Lake Winnebago presents problems for Appleton water plant
Algae, stirred sediment crimp capacity of filtration facility
By Steve Wideman Post-Crescent staff writer

APPLETON — Lake Winnebago, which provides a comfortable home for the state’s lake sturgeon, isn’t quite so welcoming to the latest in drinking-water filtration technology.

The water, drawn through a large pipe, has proven difficult for the city’s five-year-old water plant to treat. The result has been a $54 million plant that's not producing to the full capacity for which it was designed, presenting possible higher water rates for customers and additional investment in the plant by taxpayers.

Utilities Director Mike Buettner points to two particular challenges: algae in late summer and dirt in winter.

Both can wreak havoc on the filtration system, resulting in the breaking of thin straws used in the plant’s final treatment process, called membrane filtration.

“You have to have the power in these processes to settle out all those solids,” Buettner said.

The dirt is stirred up around Thanksgiving each year and again in the spring, Buettner said, “when the bottom of the lake literally turns over to become the top” due to changes in water temperature.

“It happens like clockwork when the water gets to be 38 degrees Fahrenheit,” he said.

The dirt-filled water combines with a third membrane filtration challenge — cold water — to create further problems. Buettner said cold reduces the water’s viscosity, or ability to flow through the straws.

The result leaves the water plant’s capacity at about 9 million gallons a day in winter versus the promised 18 million gallon capacity.

Since the plant went on line in 2001, operators have changed the various processes that pre-treat the water before it makes it to the straws. The actions, of course, depend on the fickle lake.

“In Lake Winnebago, the water quality changes seasonably and is not the same from year to year,” said Nicholas Powell, vice president for municipal business at Koch Membrane Systems, Wilmington, Mass., the firm that supplied the technology.

“It’s been a case of gradually optimizing all the (water treatment) processes together to make sure the plant works better,” Powell said.

Buettner said the problems are truly unique. “You won’t find the same water conditions anywhere else.”

Steve Wideman can be reached at 920-993-1000, ext. 302, or by e-mail at swideman@postcrescent.com.