Boats puttered by slowly in a Lake Minnetonka channel Saturday as Deputy Shawn Eberle flipped on blue and red emergency lights.

“Do you know why I stopped you?” he asked the driver of a yacht.

He pointed to buoys marking where boats are required to go 5 miles an hour between channels, telling the driver he didn’t slow down soon enough.

“Be safe,” he said, giving the driver a warning.

Eberle is one of eight deputies and 22 special deputies in the Hennepin County Sheriff’s Office’s water patrol unit, overseeing boating enforcement, education and emergencies on Minnesota’s most popular lake. In its six decades, the unit has grown to one of the biggest and busiest water patrols in Minnesota, overseeing waterways from massive Minnetonka to the Mississippi River.

This weekend, deputies and law enforcement across the state were out in full force for the final big boating weekend of 2016. This season was the deadliest in recent years on Minnetonka, the Twin Cities’ largest lake, with three people killed while boating.

That coincides with a rise in deaths statewide, with 14 people killed in boating incidents — on pace to reach an 11-year high, the Department of Natural Resources said.

On Lake Minnetonka, there’s no clear reason for the rise in deaths, but deputies said boating inexperience and alcohol are factors.

“This is a fun lake to be on, and boating is a fun thing, and we just want to keep people safe,” said Amir Gharbi, a special deputy. “We want to set the safety standard.”

On the job with the patrol

As boaters soaked up sunshine Saturday, Gharbi scanned ahead with binoculars as Deputy Jeremy Gunia drove one of three water patrol boats on the lake. Club music blasted from boats tied together on Big Island’s Cruiser’s Cove, a popular party site.

For deputies, the job of patrolling Minnetonka and the county’s 106 other lakes and rivers is anything but glamorous.

They are charged with enforcing a patchwork of boating laws depending on the lake or river or whether temporary no-wake rules are in place. They stand for most of their 10-hour shifts, often in hot sun, and backup is usually farther away. It’s also harder to see violations from the water, so they use binoculars to see if people are gunwale riding or children are not wearing life jackets.

Special deputies like Gharbi help, and while they can’t carry a gun or Taser like their licensed colleagues, their roles are similar. As volunteers, they complete 16 hours of training or more.

Gharbi, an Army veteran, was drawn to the role for the community service. He volunteers for two eight-hour weekend shifts a month. As an Osseo physics teacher, he has a passion for education, even if it’s schooling boaters.

“We’re not lifeguards,” he said. “It’s about behavioral changes … the rules of the road are different on the water.”

In the winter, the water patrol unit, which also has two sergeants and one lieutenant, transitions to traversing waterways by snowmobile and airboat, teaching ice safety and responding to cars or snowmobiles breaking through ice.

“Everyone thinks it’s ‘Baywatch’ out here,” Lt. Kent Vnuk said before the July 4th weekend. “Everything is the same on the water as [patrolling] on land, just more difficult.”

‘A whole other world’

On the 14,000-acre Lake Minnetonka, deputies navigate a tangle of bays and channels, waving to anglers on shore as well as boaters.

On a busy weekend, the wealthy west metro lake can draw upward of 9,000 boats — and the occasional celebrity. It also racks up about half of the state’s boating while intoxicated (BWI) charges.

“It’s going to be a busy night,” Eberle said.

Two men renting a WaveRunner for the first time were speeding in a channel ahead. Eberle gave them a warning and a pamphlet on lake rules.

Minutes later, he stopped a pontoon for passengers sitting illegally outside the boat. Smelling alcohol on the driver, Eberle questioned him. The driver said he had two beers, but Eberle didn’t believe him, seeing his watery eyes and beer cans piled up.

“I just want to make sure you’re OK to drive,” he said.

As Gharbi held the boats together, Eberle questioned the driver, who messed up his ABCs and struggled with an eye test. A breathalyzer showed the driver had a blood alcohol content of 0.06, under the legal limit. Relief set into his face as Eberle warned him to be safe and not drink more.

Locally and nationally, alcohol is the top factor in boating fatalities and accidents. On Minnetonka, there was one death last year from carbon monoxide poisoning and no boating deaths in 2014.

Boating deaths prompted Hennepin County to start a water patrol in 1955, when 18 people died, part of a trend of double-digit water-related deaths.

Neighboring Ramsey County started a water patrol unit in 1960 and now has three full-time and five part-time deputies, one commander, one sergeant and 55 reserve deputies. The DNR also assists on metro area waterways, including Minnetonka.

“Lake Minnetonka is probably the most patrolled [inland lake] and has the most law enforcement of any other body of water in the state,” said Lt. Adam Block, who oversees the DNR’s west metro team.

As the sun set, Eberle stopped another boat for speeding in a quiet water area, then gave ice cream coupons to kids for wearing life jackets.

“Every time we stop, we do a safety inspection,” he said.

Boats piled into a popular lakeside restaurant as Eberle passed by. Until 2 a.m., he would be watching for speeding or intoxicated boaters.

But he also sees a different side to the large lake known for its crowds and rowdy parties, relishing the bright pink-orange sunset, then the shooting stars across the sky as the lake grows quiet and dark, only the lights of planes overhead.

“It’s a whole other world,” he said.