Long Lake has lost its shoreline. Dock after dock dead-ends in the weeds. It looks more like an unmowed lawn with a pond in the middle than a place where families used to water ski and fish.

Once up to 12 feet deep, the lake is now closer to three, having bounced back slightly since 2006 when the lake dried up completely.

“Long Lake was once a trophy bass lake. So when we moved here, in the first two years, my boys were catching bass like crazy,” said Brian Wolf, who owns a cabin on Long Lake. “It was like catching fish in a barrel.”

In the six-county area known as Wisconsin’s Central Sands — made up of Adams, Portage, Marquette, Wood, Waushara and Waupaca counties — residents like Wolf have watched water levels in lakes and small streams drop for years. Twenty miles north, a cold-water trout stream, the Little Plover River, just landed on American Rivers’ list of the country’s 10 most endangered rivers because of its declining flow.

The receding water levels have come as the number of high-capacity wells — those that can draw 100,000 gallons of water per day — have dramatically increased.

In the early 1950s, there were fewer than 100 high-capacity wells in the Central Sands, according to the state Department of Natural Resources. Today, there are more than 3,000 — 40 percent of the state’s total.

Farmers say they need the water to irrigate crops like potatoes and corn.

“Our groundwater is not decreasing,” said Duane Maatz, head of the Wisconsin Potato and Vegetable Growers Association, an Antigo-based group representing 140 growers. “If the flows are different, there has to be another reason.”

But water quality advocates and experts say the wells are drawing down surface water and affecting recreational lakes and streams.

“Every gallon of water that gets pulled out of the ground is a gallon that’s not going to the stream or lake it’s supposed to,” said George Kraft, a hydrologist with UW-Stevens Point and the UW Extension.

While water levels fluctuate based on rainfall, Kraft’s research shows that water in lakes near high-capacity wells have declined steadily since 2000 while those farther away have not. His research identifying agricultural irrigation as a factor in the drawdown was published in the journal Groundwater in 2012.