‘Swim at your own risk’: E. coli levels up at Boise ponds; escape the heat on these hikes

·5 min read

Ridge to Rivers, the agency that manages Boise’s Foothills trail system, has compiled a list of hikes for Treasure Valley residents determined to get outside during the area’s heat wave.

The “Beat the Heat” list can be found at RidgeToRivers.org. It features suggestions for shady trails in the Foothills, as well as trails with water access and higher-elevation routes that should be cooler despite the heat. They include Five Mile Gulch, Cottonwood Creek and Dry Creek trails.

Ridge to Rivers director David Gordon told the Statesman that the trails have mostly been empty by 9:30 a.m. as temperatures begin to warm up. That’s an anomaly after a year of record-breaking traffic on the system.

Gordon said trails near Bogus Basin are a good option to avoid the heat. While temperatures in Boise have exceeded 100 degrees in recent days, the National Weather Service has forecast temperatures in the 80s on the nearby mountain.

Gordon also advised setting out to hike as early as 5:30 a.m.

“Choosing the time of day wisely is key,” he said. “And so is bringing lots of water — especially if you’re going to be bringing a pet with you. The streams are drying up pretty quickly.”

E. coli levels high at popular Boise ponds

Boise Parks and Recreation officials are advising residents to swim at their own risk at two popular Boise ponds after tests showed elevated levels of E. coli, a bacteria that can cause stomach cramps, diarrhea and vomiting.

On Saturday, Parks and Rec said in a Facebook post that Esther Simplot Pond I had unsafe levels of E. coli. The pond, located north of Friendship Island at Esther Simplot Park, is the second-largest of three ponds at the park.

In an email Tuesday, Parks and Rec director Doug Holloway told the Statesman new tests showed the problem hadn’t cleared up at Esther Simplot Pond I — instead, the agency also detected elevated E. coli levels at the beach area of neighboring Quinn’s Pond, too.

Holloway said Parks and Rec would post warning signs on Wednesday morning, but the ponds are not fully closed.

“We’re working on treatment as quickly as possible and are encouraging users to head over to the east end of the pond at Bernadine Quinn Riverside park, where the levels are extremely low, or to Veterans Park pond,” Holloway said.

E. coli and algae blooms have closed ponds at the parks several times in the past. In 2017, the city banned dogs from swimming at both parks in an effort to curb bacteria levels. It also began diverting water from the nearby Boise River in 2019 to increase water flow and circulation.

Holloway said “hot weather” and “extreme frequent use” likely contributed to the E. coli problem.

“It’s a perfect breeding ground for increased bacteria levels,” he said.

Algae bloom detected at Lake Cascade

Officials have detected an algae bloom in one of Lake Cascade’s northern arms, the Idaho Conservation League said in a news release Monday. The bloom has raised concerns about potential toxicity, as well as the impacts of drought and the region’s heat wave.

Friends of Lake Cascade, a volunteer group that aims to improve the lake’s water quality, first reported the bloom on June 16. It was found in the Boulder Creek Arm Tributary, the smallest of several tributary arms flowing into the lake.

Though the Idaho Department of Environmental Quality has not issued any warnings about the bloom, saying tests show it has not produced toxins, the Idaho Conservation League urged recreators to use caution when swimming in the area or allowing pets to swim in or drink from the lake. Algae toxins can cause muscle weakness, dizziness, stomach pain, vomiting, diarrhea and other ailments, according to the CDC. The toxins can kill livestock and dogs.

More recent social media posts from Friends of Lake Cascade suggest that last week’s windstorms may have helped disperse the algae. One member of the group told the Idaho Conservation League that it’s one of the earliest algae blooms he’s seen in the area.

Jonathan Oppenheimer, external relations director for ICL, said warmer temperatures and low water levels because of widespread drought may have contributed to the early bloom.

Ketchum woman charged by black bear foraging in trash cans

A Ketchum woman was charged by a black bear that was frequenting the area to scavenge food from residents’ trash cans, according to an Idaho Department of Fish and Game news release.

Fish and Game said the Ketchum Police Department was notified of sightings of “a very large black bear” on the evening of June 22. A Ketchum woman decided to take a walk around her neighborhood several hours later, in the early morning of June 23. She was carrying bear spray, officials said, and quickly encountered the bear.

The bear displayed “aggressive postures and vocalizations” before charging at the woman, who ran to a nearby house.

“The encounter happened so fast, she was not able to even take the bear spray out of the holster,” officials said.

According to Fish and Game, the bear had been turning over trash cans in the neighborhood to look for food. The agency said the problem is a result of residents setting out their trash bins on the curb the evening before trash pickup. Residents are “setting the dinner table for animals that can now access household garbage.”

Fish and Game and Ketchum sanitation officials urged residents to set their trash cans out the morning of pickup to reduce incidents.

Officials said a culvert trap has been set for the bear, which will be euthanized if it’s caught.

“The last thing we want to do is euthanize bears,” said conservation officer Brandyn Hurd in a news release. “But once we have a bear that is showing no fear of humans, and that acts aggressively towards people, the outcome is clear that we must take action to protect public safety.

“It’s actually a simple fix. If residents will secure their garbage and not let bears and other wildlife access it, the need to euthanize wildlife will greatly diminish.”