Algae blooms have been visible lately in quiet areas of Spring Lake, its bayous, Grand River bayous and ponds. Nash said warm weather, rain and shallow, quiet conditions contribute to the growth of algae.
Nash said he is fairly certain that some residents are still using fertilizers containing phosphorus and that’s contributing to the complaints he’s heard lately about local water quality.
Michigan’s law restricting phosphorus in fertilizer went into effect in 2012. That’s after local municipalities, and then Ottawa County, banned the use of fertilizers containing phosphorus in the Spring Lake and Grand River watersheds.
The conditions are made worse as the waterfront communities add more roads and wider roadways, and people build homes in former wetland areas, mow down vegetation at their waterfronts or landscape their waterfronts with impermeable surfaces.
It’s the vegetation that helps filter the contaminants before they reach the water.
The Spring Lake Lake Board monitors the condition of the lake and its bayous. Residents around the lake help pay for treatments to reduce algae.
Nash said the treatments are done three times a year: around Memorial Day, before the Fourth of July and before the Coast Guard Festival.
McKenzie Nelson, an employee of Lakeshore Kayak Rental in Spring Lake, said the algae off the company’s launch ramp on Lloyd’s Bayou was pretty bad until the treatment in early June.
Most of the water in the area was clear of the algae last week.
Nash said the most recent treatment began June 27.
Scientists go out and determine the areas to be treated each time, Nash said. They also go back to make sure the treatment worked after the work is done.
Nash said the Michigan Department of Natural Resources does not give the lake board permits to do the entire lake at any one time.
Each time the lake is treated, it makes an obvious difference, Nash said.
But there are things area residents can do to help protect the lake. For instance, if you live on the north side of Savidge Street in Spring Lake, anything that runs down your driveway goes into drains that empty into Spring Lake, Nash said. If you are on the south side of Savidge, the runoff goes into the Grand River.
“You don’t have to live on the waterfront for your runoff to affect the lake,” he said.
The lake board does occasional soil tests on properties around Spring Lake, and they have found them already rich in phosphorus, so there’s no need to add phosphorus fertilizer because it’s already there, even if it is legal to use it to start a lawn.
“The soil doesn’t need it,” Nash said.
And, if you don’t believe it, lawn care companies will run a soil test if you ask them to do it, he said.
Nash said you can rake up the algae, put it on your dock to dry, and then put it in your yard waste or on your garden.
Another thing people can do is read through all the information on the Spring Lake Lake Board website at www.springlakeboard.org, then you can share the information with your neighbors, Nash said.
“Spring Lake has a very challenging situation,” Nash said. “The choices people make can make a significant difference.”
Spring Lake facts
— The lake has a surface area of 1,091 acres.
— The maximum depth is 40 feet (south side of the lake, somewhat in line with Prospect Street in the Village of Spring Lake).
— The average/mean depth is 18.2 feet.
— The lake volume is 19,845 acre-feet. That would cover 31 square miles to a depth of 1 foot.
— The shoreline length is 25.3 miles.
— Spring Lake is a drowned river mouth lake that formed as a result of fluctuating water levels in the glacial Great Lakes.
— Spring Lake is the 85th largest lake in Michigan.