June 13, 2007
Corrosion of Ports
An aggressive form of corrosion has eaten away at steel pilings along commercial ports on Lake Superior, and some pilings are so worn they're on the verge of failure. Researchers are trying to pinpoint the cause of the freshwater corrosion.
Perforations affect most sheet piling with an original thickness of three-eighths of an inch or less that has been in the harbor for more than 30 years. Most 3/8-inch docks probably will face collapse in the next five to 10 years unless their steel pilings are replaced.
The steel piles became more visible as Lake Superior fell 18 inches from its average historical level. Dramatic corrosion can be seen on Coast Guard range towers near the Bong Bridge and at the foot of the Duluth Missabe & Iron Range Railway ore docks in Minnesota.
Scientists are focusing on microbes and how they affect harbor corrosion. A study of organisms found on the port's steel pilings has isolated two types of bacteria. One appears to be an iron oxidizer and the other an iron reducer.
May 3, 2007
Public Access on Lakes
State lawmakers in Michigan are reopening the argument over public access versus private property rights on lakes. A two-bill package would require the state to issue permits allowing seasonal docks or marinas where public roads end at the water's edge. Provided local governments want them there. Townships would have to pass ordinances regulating them.
The legislation, seeking to reverse a 2006 Michigan Court of Appeals decision, was sent to the House floor from its Tourism, Outdoor Recreation and Natural Resources Committee.
Until now, the issue appeared somewhat settled. Appeals Court judges ruled that local governments couldn’t allow overnight boat mooring hoists. Judges have invited lawmakers to resolve the issue, which has wound in and out of state and local courts since at least the 1880s.
Many battles have been fought at heavily developed Higgins and Houghton lakes. Higgins alone has 94 such road ends. But the proposed legal changes would affect all inland lakes, with thousands of public accesses, and is opposed by the Department of Environmental Quality.
The DEQ believes the bill would interfere with the DEQ's ability to protect the rights of all residents, instead allowing small groups such as the back-lotters to take over lake access points. The docks would block other uses, such as swimming.