MMSD awards dam contract
Madison company will demolish Estabrook Park structure in 2018
The Milwaukee Metropolitan Sewerage District’s commission on Monday awarded an $844,421 contract to a Madison company for removal of the Estabrook Park dam on the Milwaukee River and demolition work is expected to begin in January.
Terra Engineering & Construction Corp. was the lowest of six bidders for the job, officials said.
After a final federal permit is received this month, Terra Engineering could begin building an access road on the south shoreline, installing erosion control measures and other preliminary work in late December, MMSD senior project manager Tom Chapman said.
Demolition is expected to be completed in 2018, according to Chapman. The dam is located nearly 1,500 feet downstream of the Port Washington Road bridge.
Monday’s unanimous commission action comes nine years after state officials ordered then-owner Milwaukee County to open dam gates in 2008 due to numerous safety problems found in inspections.
In 2009, the state Department of Natural Resources ordered the county to remove or repair the 1930s-era dam.
After years of inaction by the county, MMSD this year bought a 45.7-acre parcel at Estabrook Park for $1 for the purpose of demolishing all of the dam structures. Much of the property was returned to the county for park use at the time of the sale.
In addition to a dam with floodgates extending from the north bank of the river to an island at midstream, a serpentine concrete and stone wall, known as a fixed spillway, extends from the island to the south bank of the river. A series of concrete ice barriers are located upstream of the dam section with floodgates.
The contract also requires removal of a control building on the north bank of the river and excavation of an estimated 250 cubic yards of sand and muck from the riverbed immediately upstream of the spillway.
MMSD has received a total of $2.3 million in grants that will fully pay for dam removal, MMSD Executive Director Kevin Shafer said.
In addition to demolition work, the district estimates it will spend $1 million on engineering design, postdemolition restoration of the river banks and removal of a temporary access road on the south shoreline.
Taking out the dam will improve water quality, reduce flood risks to upstream properties, restore a natural passage for fish swimming upstream from Lake Michigan, and save public funds, Shafer said.
When dam gates were closed in the past, algae would grow in the stagnant pool of water held back by the dam, said Will Wawrzyn, a consultant for MMSD. Muck would accumulate in the bottom of the artificial pond.
Removal of the dam will lower the floodplain by as much as one foot in some upstream locations, according to Chapman.
More than 50 homes will be removed from revised floodplain maps. Most of those residences are located between Silver Spring Drive and Mill Road in Glendale, Chapman said.
The most recent county dam repair plan would have corrected safety problems, added floodgate control upgrades, and a fish passage around the dam, at an estimated cost of $4.1 million.
Operating and maintaining the dam would have cost an additional $160,000 a year, or $3.2 million over 20 years, under the county plan.