Record-low lake levels a force to be reckoned with

There’s plenty of room for a walk on this Union Pier-area beach.

By William F. Ast III
For the News

The problem is easy to see.

Take a look at the St. Joseph River. It has some new small islands where there were no islands before.

Or consider the harbors in New Buffalo and South Haven. Both cities are doing a lot of dredging to make sure boats can get in and out of the harbors with no trouble.

The level of Lake Michigan is near a historic low.

That’s great for people who like the beach. There’s plenty of beach to enjoy.

And it’s both a relief and a pain for those who own houses along the lake. Their houses aren’t being threatened by high water, but some are seeing beach vegetation growing between them and the water

Why should people care? Low lake levels only affect beachfront owners and boat owners, right?

Wrong, according to Andrew Gronewold, a hydrologist for the National Oceanic and Atmospheric Administration’s Great Lakes Environmental Research Laboratory in Ann Arbor.

“The Great Lakes constitute more than 90 percent of America’s fresh surface water,” Gronewold said. “The Great Lakes are vital to the North American economy. And I’ll give you one more fact.

“We’ve learned some numbers on how much fresh water there is on the planet. Here’s one. Lake Baikal (in southeastern Siberia), Lake Tanganyika in Africa, and the Great Lakes, they collectively hold about half the earth’s unfrozen fresh water. Half, in just those three lake systems … If that doesn’t grab you, I don’t know what would.”

Gronewold said water levels on Lakes Michigan, Superior and Huron have been “predominantly below average since around 2000.” Lake Erie is about normal, as is Lake Ontario, though “part of that, as you know, is that Lake Ontario is regulated,” he said.

Lake levels were at an “all-time high” in 1986, Gronewold said in a phone interview. “The take-home message is that a water level drop in the late 1990s really set the stage for the low-water levels,” especially on Lakes Michigan and Huron, he said.

Water levels then remained stable until 2012, “and it was in 2012 that we had a lot of different things happen,” Gronewold said.

“One is, beginning in 2012, we had an incredibly warm winter with hardly any snow pack,” he noted. “We also had a drought.”

Gronewold chuckled, but said he’d chuckled because all those factors coming together at one time was incredible, not because it was funny.

“Because the water temperatures were so warm, and we had so little ice cover, then we had above-average evaporation” on the lakes, he said.

“Precipitation over the lake, evaporation over the lake, and the runoff coming into each of the lakes – those are the three major drivers of water level changes over time,” Gronewold said. “The are the big factors behind water levels rising from the previous low of 1964, and the major reason water levels have dropped since 1986, when they reached their all-time high.”

The U.S. Army Corps of Engineers says Lake Michigan is currently close to 2 feet below its long-term average of 579 feet above sea level. Lake Michigan was at 577.15 feet on May 12, up a bit from 577.05 on May 1.

The average in 2012 was 577.6 feet. The lowest level in 1964 was 576.6 feet, and the highest in 1986 was 581.6 feet.

Gronewold said the situation has eased a bit of late. Abundant rainfall this spring, about 150 percent of average, raised the levels of Lakes Michigan and Huron about 6 inches in April, according to the Corps of Engineers. But a lot more precipitation is needed to return the lakes to their normal levels, officials said.

According to The Associated Press, an advisory panel has recommended that the United States and Canada think about using artificial structures to retain more water in Lakes Michigan and Huron.

The International Joint Commission said “placing structures” in the St. Clair River, at the south end of Lake Huron, might be useful in raising water levels in the two lakes. That might boost water levels anywhere from 5 to 10 inches, commission officials said. Dredging in the river did contribute to the low lake levels, commission officials conceded. But the dredging wasn’t the main culprit — drought and evaporation are the biggest causes, they said.

In New Buffalo, one dredging project (of the upper harbor area from the Whittaker Street Bridgman to the city boat launch)  is under way while another from the bridge to the lake is slated to begin in June. Dredging has been necessary for five of the past six years, said Ryan Fellows, assistant city manager.

It’s important work, Fellows said. New Buffalo’s harbor generates $7.7 million in revenues throughout the Harbor Country area and supports an estimated 130 jobs that generate $2.5 million in labor income, he said.

As to what’s causing New Buffalo’s problems, Fellows said a variety of factors, including the low level of Lake Michigan, are at work.

“One is the littoral (shore) current of Lake Michigan that is depositing sand on the city beach side of the breakwater,” Fellows said. “The breakwater has sunk about 2 feet from when it was first put in, and it’s no longer holding back sand as it was designed to do. It’s depositing it into the harbor mouth.”

Besides that, the Galien River carries sediment into the harbor, and runoff from the city beach and other runoff areas contributes, Fellows said.

The breakwaters are “an interruption to the natural flow of the lake,” Fellows said. “Mother Nature will always win. It’s just a matter of time. It’s like a paved road, which will have grass growing through it eventually. Mother Nature always wins.”