At the south end of Elk Lake, swimmers stood in a semicircle around Bob Bruce, a longtime coach with Central Oregon Masters Aquatics and organizer of the Cascade Lakes Swim Series. Bruce looked out at more than 150 eager participants — a group diverse in age and body types, but almost uniformly wearing bright blue swim caps.

“If you’re in trouble, put up a hand, and one of our kayakers will come get you,” he bellowed to the swimmers.

Behind where Bruce was standing, event organizers on kayaks and paddleboards waited on either side of a 250-meter-long line of buoys, which pointed north toward a picturesque view of South Sister. Open-water swimming at high altitudes can be hard on the lungs, but at least it is easy on the eyes.

The first of two races scheduled for Saturday was of 500 meters — one trip out toward the center of the lake and back to shore. It started with a wide-legged, splashing sprint through shallow water before swimming a tight, extended loop, and for many it finished with an exhausted trot out of the lake and through the finish line.

Hailey Bambusch, 27, from Portland, was one of the first to start and finish the race. Starts were staggered to keep things orderly, and Bambusch was near the front of the line because of the times she submitted from previous races. Her experience with the masters team at Multnomah Athletic Club prepared her for this year, her third time participating in the Cascade Lakes Swim Series.

“There’s no lane lines or structure to it, so it’s a major mental game,” she said. “You’ve got to prepare that way, and it’s harder because of the waves and the altitude.”

In its 24th year, the annual series consists of five swims over three days. A 3,000-meter race opened the series on Friday evening. Races of 500 and 1,500 meters were staged on Saturday, and 5,000- and 1,000-meter races took place Sunday.

According to swimmers, the water was not as choppy on Saturday morning as it had been on Friday evening, making for an easier (and much warmer) swim despite some of the inherent challenges that go along with the 500-meter event. The water Saturday was about 70 degrees, according to Bambusch.

Other than the temperature, a notable challenge that affects swimmers young and old is the altitude, which is nearly 4,900 feet on the surface of Elk Lake.

Eighty-four-year-old David Radcliff knew what to expect. He had been coming to this event for more than 20 years. A self-described “flatlander” who lives in Hillsboro, he takes necessary precautions to keep from tiring himself out.

“I have to be careful at my age going out and coming in,” Radcliff said. “I don’t run very hard (into the lake), because that just takes your breath away.”

Swimmers younger than Radcliff — which was almost everybody — were in awe of his athletic ability at 84. He said he started open-water swimming as a teenager in San Diego, where one of his coaches, he recalled, sometimes held practice in the ocean. Those grueling days paid off, though, when Radcliff ended up swimming for the University of California, Berkeley, and made the U.S. Olympic team in 1956.

Radcliff returned from an extended swimming hiatus in 1995, which eventually led to a record-setting career in masters competition. He currently holds 45 individual records for long-distance and pool events in United States Masters Swimming. At this point in his decorated career, Radcliff is happy to participate in a variety of events around the country.

“I’m just enjoying life,” he beamed after finishing Saturday’s 500-meter race. “When you retire, you need to have something of real purpose to do. The swimming, the friends and being part of (USMS) has been really great.”

Camaraderie is the enduring theme of masters swimming events, particularly the Cascade Lakes Swim Series, which is hosted by Central Oregon Masters Aquatics. The weekend of friendly competition forms a bond between novices, seasoned swimmers and everyone in between, most of whom camp together along Elk Lake during the series and take in the natural beauty of Central Oregon.

For Sandy Beelmann, 56 and a Bend resident, this was her second time at the annual swim series. She said the friendly atmosphere drew her in, and it will keep her coming back every year.

“Being out in a beautiful venue like this with people you feel comfortable with, that’s a unique experience,” Beelmann said. “It’s amazing.”

— Reporter: 541-383-0307, rclarke@bendbulletin.com