By RAY WILBUR
Capital News Service
LANSING — While people in Florida gear up for more intense hurricanes, Michigan officials are bracing for heavier rainfall caused by global warming ,and that threatens the state’s aging drains and the Great Lakes.
Local drain commissioners are questioning how to handle the influx of water and the problems it brings.
And more intense, heavier rainfall has become more prevalent in Michigan, said Joan Rose, an international expert in water microbiology, quality and public health at Michigan State University.
That causes trouble not only for the state’s old drainage systems and its water sources but for animal and human health, she said.
“When it rains, the water moves contaminants quite broadly,” Rose said. “In a summer storm event, the whole state basically turns red with contaminants.”
Contaminants include trash, microorganisms, sewage and other nutrients that cause toxic algae blooms in lakes.
Rainfall is not only heavier — it’s faster when it’s on the ground, making it difficult to control what flood water carries and where it ends up, said Pat Lindemann, the Ingham County drain commissioner.
Some drainage pipes are 100 years old, he said. Many are inadequately sized for the storms that have now become common.
“There is more stress on the infrastructure we have in our state,” he said. “We have to rethink the way we interact with our urban and rural areas and how water plays into that.”
Preparing for heavier storms require rewriting the standards of development and standing drainage systems, Lindemann said.
These types of storms increase flooding which can damage homes, businesses and crops, said Denise Medemar, the Allegan County drain commissioner.
Her county hasn’t experienced terrible flooding while she has been drain commissioner, Medemar said. But flooding in the past prompted drainage projects.
The Bear Swamp Drain in Allegan County is a wetland created to collect water before it can flow downstream and flood the village of Hopkins, she said. The project cost roughly $1 million.
A major factor in the increase of floods is the development of land that at once helped collect water.
In Allegan County, structures built on the Rabbit River impeded its flow and contributed to the need for flood mitigation.
Such flood control projects happening statewide are much more difficult to implement in urban areas.
“Wetlands are one of our biggest allies,” Lindemann in Ingham County said. “But now with urbanization and development, we’ve seen a lot of those areas taken away and turned into shopping.”
Projects that preserve or create areas for water to collect are becoming much more common, said Evan Pratt, Washtenaw County water resources commissioner.
They include increasing the size of ponds or streams, constructing water basins or preserving old ones and installing new or bigger pipes.
Most Michigan drainage pipes are old, Pratt said. Even those that last a long time weren’t designed to handle the amount of water that flows through them now.
“Local areas are really starting to realize the negative impacts this rainfall can have,” Pratt said. “I think there is plenty of time, but things do need to be done.”
The poor drainage threatens the Great Lakes, said James Clift, Michigan Environmental Council’s public policy director.
Floods can increase algae blooms in the Great Lakes and threaten aquatic and human life, Clift said.
The summer of 2015 saw the largest algae bloom in Lake Erie in 100 years and while it didn’t reach earlier toxicity levels of 2011, the bloom covered 300 square miles and threatened the safety of drinking water.
If the state doesn’t begin addressing how rain can impact lakes, algae blooms could be much more frequent, Clift said.
By RAY WILBUR