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Strategic plan targets invasive species
The Superior Daily Telegram (11/17)
Douglas County’s Land Conservation Committee is forwarding a plan to the county board that takes aim at invasive species.
Mich. Clean Marina Program: Public-private partners work together to improve water quality
Grand Rapids Environmental News Examiner (11/9)
Partners from the public and private sector in Michigan are working together in a voluntary program to improve the quality of the Great Lakes.
Researchers seek funding for wind test site in Lake Michigan
Grand Rapids Environmental News Examiner (11/7)
In a recent article in The Muskegon Chronicle, it was reported that researchers at Grand Valley State University’s Michigan Alternative and Renewable Energy Center (MAREC) cited a lack of year-around data (on wind platform testing) needed by prospective development companies.
COMMENTARY: Senate needs to pass clean energy act to help Michigan
The Grand Rapids Press (10/26)
Senate Majority Leader Harry Reid was absolutely correct with his recent proclamation about the current condition of the Great Lakes State: "The State of Michigan," Reid declared from the Senate Floor, with a copy Time Magazine in his hand, "is in trouble."
First Nation women 'walk the environmental talk'
WeNews (10/23)
Tomorrow's global day of climate activism aims for media and political attention. First Nation women have another way. Since 2003, they've walked the shoreline of a Great Lake or major river, meditating on the needs of an unborn generation.
City making big push for water school
The Business Journal (10/23)
The push is on to convince the University of Wisconsin-Milwaukee that the best location for its new School of Freshwater Sciences is near the university’s existing Great Lakes Water Institute on East Greenfield Avenue.
What's going on in your neighborhood this month? Meet other people and learn together at recreational and educational events! Our new dynamic calendar is updated daily with current educational events.
2 | The construction period: 1954-57
Because the bridge was in a remote area, financing the project was slow and difficult. The total cost of the project was upwards of $100 million (originally estimated at $70 million).
Construction began in 1954 and during the 42 months that followed hundreds of men worked on the various phases of the bridge construction.
The first step was to sink the large, double-walled cylinders that form the bases of the two main tower piers. These cylinders are called caissons (cay-säns). The caissons had to be sunk down into the bedrock on the lake floor, a great challenge for the divers involved.
When the foundation pillers were finished, the iron workers were brought in to string the massive cabling network! More than 500 workers were housed in St. Ignace, Mich., during this construction period.
A "catwalk" made of cyclone fence enabled the workers to navigate between the bridge towers, high above the lake below.
When finished, the cables were close to 25 inches in diameter. Each cable consists of 340 wires banded into a single strand; 37 strands are then assembled into a single cable. To complete the job and add extra strength, a covering is spun around each finished cable. More than 42,000 miles of wire were used in the two main bridge cables!
The last step was to construct the road surface. The inner lane on the middle span of the bridge includes an open grid riding surface. This was installed to allow wind forces to move through the bridge.
Images: Erecting the north tower and adding trusses and cables, courtesy "Picture Story of the Mackinac Bridge," 1978 Voyager Press; the Mighty Mac close to completion in 1956, courtesy Albert Ballert.
