Main Street saddle work starts Monday

First phase to cover 100 block of South Main

The city will start its Main Street water main saddle replacement project on Monday, with the first phase targeting the 100 block of South Main Street.

The plan is to have that part of the project completed before the Octoberfest festivities hosted by the Business Improvement District on Oct. 6.

Traffic will remain open during the work, but there won’t be any street parking. Several business have been promoting parking in the back during the project. There is also parking available in two city lots behind the businesses.

The entire project will cover Main Street from just south of the channel to the end of the 200 block of South Main Street. It should be completed by the end of October.

At issue are stainless steel saddles (a type of metal sleeve) that hold the service connection to the water main. They were installed during the Main Street reconstruction project in 2002 and 2003. The project stretched from the channel to the Mountain Bay Trail at Oshkosh Street.

The Shawano Common Council approved borrowing up to $180,000 from the Shawano Lake Sanitary District to cover the cost of replacing 71 saddles along Main Street.

The loan will be paid back over a five-year period with an interest rate of 3 percent.

The project is being done by DeGroot Inc.

Funding for the project will come from the Department of Public Works’ water utility fund, though the utility will borrow the money from the State Trust Fund.

A corroded saddle was blamed for a water main break outside Dreier Pharmacy at 117 S. Main St. on Jan. 4, the latest in a series of saddle failures over the last several years.

The city has been plagued with failing saddles starting in 2009.

Two water main breaks occurred in the 100 block of North Main Street in February 2009 and December 2010, only about 50 to 75 feet away from one another. Another saddle failed in the 200 block of South Main Street in September 2013.

It was determined that high levels of chloride in the soil were responsible for those saddle failures.

Random soil tests were done in 2015 by Mach IV Engineering, of Green Bay. Out of 20 locations sampled, chloride levels above 500 parts per million were found at three locations. Five others had chloride levels above 300 ppm.

The stainless steel used in the saddles could start to deteriorate at chloride levels over 300 ppm, according to city officials. At levels above 500 ppm, the deterioration is much faster.

Chloride levels in the area of the three previous water main breaks were in the range of 900 ppm, as a result of years of street salt seeping into the soil.

The city hoped it had solved the problem after it hired Grunewald Inc. in September 2015 to replace stainless steel saddles at eight Main Street locations where they were at risk for potential corrosion.

Three of the saddle replacements took place in the 100 block of North Main Street, two in the 100 block of South Main Street, one in the 200 block of North Main, one in the 200 block of South Main and one in the 100 block of West Fourth Street.

One of the saddles replaced was just south of the one that failed on Jan. 4.

The new saddles, which will be brass this time, will be wrapped in heavy plastic, and additional backfill will be added to protect the saddles from the chloride.