Fastest-Growing Michigan County Reckons With Groundwater Pollution and Depletion

Ottawa County leaders recognize the need to act on groundwater.

By Brett Walton, Circle of Blue

The dry wells, not more than 15 miles from Lake Michigan, one of the largest bodies of fresh water on the planet, were the first alarm bells for Ottawa County.

It happened a little over a decade ago, back in 2007, when wells supplying drinking water to new homes in the Highland Trail subdivision of Allendale Township started to sputter and then blink out. Allendale is in the north of Ottawa, which has been the fastest-growing county in Michigan since at least 2010. The expansion is propelled by proximity to Grand Rapids, the economic engine of western Michigan and one of the nation’s highest-growth metropolitan areas.

Then came complaints from farmers. Leaves on their soybeans had been “burned” – turned brown and crispy on the edges – because their irrigation water, pumped from deep wells, was becoming too salty. Half farmland, the county has one of the most diverse agricultural operations in the state, with apple orchards, flower nurseries, blueberry patches, and row crops like corn and soybeans.

Those incidents raised eyebrows among county leaders, according to Paul Sachs, then the assistant director of the Planning and Performance Improvement Department.

The stories they heard sounded more like those from Arizona or California or the Texas Panhandle, dry regions where scarcity reigned, or Hawaii or Miami, where fresh groundwater is precariously balanced atop saltier layers. Leaders soon realized that something was amiss in a land of supposed plenty.

“The mindset was that because we’re on the shore of the Great Lakes water is pervasive. But even here water conservation is important,” Sachs, now the department director, told Circle of Blue.

“We’re not an arid state, but we still have water challenges,” he added.

Those challenges are better defined now thanks to a six-year study from Michigan State University that was commissioned in response to those incidents a decade ago. The study, which concluded earlier this year, found that Ottawa County faces a two-headed emergency: declining aquifers that are becoming more polluted with salts and nitrates.

And it’s not just Ottawa. The study identified three dozen other Michigan counties where intensive groundwater pumping will invite saltier water to invade from below.

“Michigan’s fresh groundwater is sitting on a pool of brine underneath,” Shu-Guang Li, the Michigan State University researcher who led the study, told Circle of Blue. “We talk about the Great Lakes, but deep underground, it’s salty.”

The groundwater emergency is a homegrown challenge, but one that Ottawa County is not dodging. Allendale Township instituted a six-month moratorium last month on new housing developments that plan to use wells. The county, meanwhile, is developing a strategy that will convert findings from the Michigan State study into actions to protect groundwater.

Depletion Worsens Pollution

The study, funded by the Ottawa County Planning Commission and the Michigan Department of Agriculture and Rural Development, unfolded in two parts.

The first report, published in 2013, sketched an outline of the problem, which links water-use behavior at home and on the farm with the county’s underlying geology.

It was clear from existing well measurements that an increasing reliance on groundwater was depleting deeper aquifers and causing groundwater quality to deteriorate. Well water, in certain areas, was becoming too salty for crops and off-putting to drink.

The first study also noted elevated nitrate levels in shallow groundwater. In a half dozen hotspots, researchers found nitrate concentrations two to five times higher than the U.S. Environmental Protection Agency standard for drinking water. High nitrate levels increase the risk of infant death from methemoglobinemia, known more commonly as blue baby syndrome. Recent studies that traced health outcomes over decades have also shown a higher risk for cancers of the bladder, colon, thyroid, and kidneys at even lower nitrate exposures than the EPA standard.

Nitrate levels at the hotspots did not vary much over time, suggesting that the sources, most likely farms and septic systems, were “persistent and prevalent.”

The second report, published in March of this year, revealed a curious connection between groundwater use and the rising concentrations of chloride, or salts, in well water.

A layer of sandstone called the Marshall aquifer runs beneath Ottawa County, and most household and farm wells draw water from it. Below the freshwater layer are briny waters. When water levels in the Marshall aquifer drop, briny water is pulled upward, accelerating natural upwelling that occurs. Water levels in wells south of Allendale dropped, on average, 45 feet in the last five decades, and the groundwater has grown saltier.

“Essentially, if you go too shallow you have the nitrate problem, and if you go too deep you have the chloride issue,” Li said. “That’s the dilemma.”

Currently a quarter of Ottawa residents use a household well, according to the U.S. Geological Survey.

Making matters worse, an impermeable clay layer above the Marshall formation impedes rain from percolating downward to flush out the salts.

Based on similar geology, the research team identified three dozen other low-elevation counties in southern and eastern Michigan that are at risk of chloride contamination from groundwater pumping. Most susceptible are the counties along Saginaw Bay, they found.

“This is not a problem that is limited to Ottawa County,” Li said. “Ottawa County is just more proactive.”

Sachs and colleagues in the planning department will use the study to develop a groundwater protection plan. Included will be a thorough review of county policies and regulations on the placement and design of wells and septic systems. Additional studies will take place. Grand Valley State University will survey the county for land where the soils are most suitable for recharging the aquifer. Sachs said that the county could preserve that land from development.

Education and outreach to local communities will be essential as well, to garner support. “Conservation needs to be practiced by everyone,” Sachs reiterated. He’s thinking about ways to incentivize homeowners to collect rainwater because “using drinking water for lawns may not be best.” A draft plan will be ready in the spring of 2019, he said.

Groundwater Concerns Guide County Policies Today

Even before the plan is in place, the threat of groundwater depletion is swaying county land-use decisions.

In August, Allendale Township passed a six-month moratorium on new housing developments that are not connected to public water and sewer.

The moratorium was partly spurred by concerns over Trader’s View, a 52-unit housing development. Neighbors told the township planning commission that they worried about their wells going dry. They cited Highland Trail as a cautionary tale. (To fix that problem, Allendale ended up spending $2.6 million to extend public water to Highland Trail. Homeowners are repaying the cost via assessments.)

Trader’s View developers ended up reversing course. Instead of 52 additional wells, Trader’s View homes will hook into Allendale’s water system. Like most public systems in the county, Allendale Township delivers Lake Michigan water to customers, which does not have the same supply and pollution risks as wells.

Adam Elenbass, the township supervisor, told Circle of Blue that the moratorium allows town officials to consider what protections need to be put in place for groundwater.

That’s the type of thinking that county administrators hope will spread.

“It’s not a problem we can continue to ignore,” Sachs said. “If we continue to operate with blinders on, we’ll have a significant challenge down the road.”