By Shaun Hall • Rogue Valley Times

Any day might be a good day to visit the Kenneth Denman Wildlife Area near White City, but a hot summer weekend is a pretty good time to get a first-hand look at how commercial jet boats might be impacting the Rogue River.

A chorus of riverfront property owners, conservationists and anglers are calling for a ban on the boats upriver of the nearby TouVelle State Recreation Site. Much of their concern is directed at Rogue Jet Boat Adventures, which has been operating on the river in Jackson County since 2011. Immediately upriver from TouVelle is Denman, where the river narrows and curves.

My wife and I pulled up to the rocky north shore at Denman about noon on Saturday, June 22. A couple, Ryan Case of Gold Hill and Hawley Pruett of Medford, was already there, sitting in chairs and soaking up the sun at the river’s edge, music playing not too loudly.

“I don’t think it’s that bad,” said Case, when asked about the jet boats. “I like seeing them go by, having fun. They slow down.”

“I always enjoyed them,” said Pruett, who had ridden Hellgate Jetboat Excursions boats operating out of Grants Pass.

Over the next three hours, river traffic was light: one drift boat, two rafts and four kayaks floated by. Also, a total of five anglers fished from shore or waded into the river during that time, and four other vehicles pulled up to the shoreline within sight, with some visitors wading into the frigid water.

Ducks quacked. Dragonflies darted about. And jet aircraft taking off from the Medford airport flew overhead, adding to the medley of sound.

A bit after 1 p.m., the first of two jet boats sped around a curve and headed our way. The video camera application on my smartphone was running.

That day, the company was running three trips, at 9:45 a.m., 1 p.m. and 4:15 p.m. Depending on the number of passengers, the company uses up to three boats holding 12, 18 and 25 passengers, respectively.

About 11 people were on board the first boat, which left a wake that came ashore at under a foot high. On its return trip, the boat puttered by, leaving no wake until it was past our area, which by then had more visitors on shore and in the water.

The second boat, carrying about 18 people with room for more, produced a sound level of 85 decibels while headed upriver, close to the 90-decibel level mentioned by Bob Hunter of the Applegate Valley, in a letter to the Oregon State Marine Board. Hunter is a leader in Upper Rogue Guardians, a group opposed to the jet boats.

“The danger, noise … wakes, erosion and dislodging of aquatic vegetation from the operation of a commercial jet boat in this stretch of river adversely impacts the public’s use of these lands and the wildlife that inhabits them,” Hunter wrote.

Busy traffic generates a decibel level of 80, while a motorcycle generates a decibel level of 90, according to Decibel Meter Pro, a downloadable application I used on my smartphone.

The river where we were was maybe 75-100 feet across. Across the water, a bank maybe 15 feet high was eroded.

“I think nature did that by itself,” Case said.

Contacted a few days later by phone, Phil Simpson, district watershed manager for the Oregon Department of Fish and Wildlife said jet boats “absolutely” can have an impact on riverbank erosion, but he was unsure what caused the erosion at that spot. Among the causes of erosion are vegetation removal from the bank, shifts in the river, changes upriver and changes in peak flows, according to Simpson.

“Oftentimes, it’s a function of the river doing its thing,” he said. “It can be so many different things.”

Taylor Grimes and his wife, Emily, own Rogue Jet Boat Adventures. They point to a 1995 ODFW study that focused on impacts to juvenile fish. The study is cited in a management plan published in 2000 by the U.S. Bureau of Land Management for the Hellgate Recreation Area, downstream of Grants Pass, where Hellgate Jetboats operates.

“(The study) concluded that all watercraft disturbed the fish, however, slow moving watercraft and people wading in the river disturbed fish the most,” the plan states.

The plan quoted another study, a 1993 Oregon State University report: “Most erosion was naturally caused and some erosion was due to motorized boats and other human-caused sources.”

Frances Oyung, program director for Rogue Riverkeeper, a program of the Klamath Siskiyou Wildlands Center of Ashland, said river studies in Jackson County were lacking, but she provided studies done in Alaska and elsewhere.

“Even if there are no studies specific to the Upper Rogue on jet boats, other studies can be interpreted to have similar impacts,” she wrote in response to a request for comment. “It is known through many studies and data collection as well as basic observation that motorized boats and especially jet boats disturb sediment and substrate and aquatic plants, and affect turbidity.”

“We know that salmon are highly dependent upon a specific habitat to spawn and alterations to substrate can have a big impact on their ability to reproduce,” Oyung wrote.

Simpson agreed there was a lack of local studies, but said information can be extrapolated from studies done elsewhere.

“There’s not a huge body of literature out there on impacts of boats on ecosystems,” he said, adding that additional studies of the Upper Rogue River are under consideration.

Dan Van Dyke, a fish biologist with ODFW, wrote to Oregon State Parks in November 2022 about limiting impacts from jet boats. He wrote that anglers had complained about aquatic vegetation being dislodged and that landowners claimed damage to riparian habitat from the tour boats. Without confirming that actual damage had been done, Van Dyke recommended that the state and jet boat company work to evaluate conditions and create a prevention and repair plan as needed.

Van Dyke also recommended against allowing jet boats above Rattlesnake Rapids, the farthest point upstream where Rogue Jet Boat Adventures operates. The virtually impassable rapids are about 5 miles upriver from TouVelle and about 2 miles downstream from Dodge Bridge and Highway 234, well downstream from Shady Cove. Van Dyke also recommended that tour boat operations below Rattlesnake Rapids cease between Sept. 11 and April 30. The company operates tours from May 1 to Sept. 8 at the latest.

After my wife and I left the wildlife area shortly after 3 p.m., we went to TouVelle to catch the 4:15 p.m. jet boat tour leaving the park. We got aboard with several others.

“We will be running into river traffic,” operator James Dyer told us. “I slow down, stop, do whatever I need to do to be safe.”

And that is what he did, shutting down to idle speed several times when headed upriver and encountering river traffic headed downstream. He also shut down to no-wake speed while passing rafters, swimmers and fishermen encountered while the jet boat was headed downstream.

“To be kind and courteous and safe, we’re going to wait,” he said as one party floated by.

Dyer, a U.S. Coast Guard certified mariner, took the boat to Rattlesnake Rapids and then back downriver past Denman and TouVelle, where waders were out on both sides of the river. There’s no speed limit on the river, but Dyer slowed as he approached the outlet of a side channel where it reentered the main channel at TouVelle, looking for cross-traffic.

Once past the side channel, Dyer sped off to the company’s Discovery Park, located about 3 miles downstream and across the river from Lower Table Rock. There, passengers visited for about an hour during which they could have a bite to eat, get something to drink or take a swim in the adjacent lake before reboarding.

Dyer then took everyone a couple more miles downstream, past the mouth of Bear Creek to the site of the former Gold Ray Dam, now removed, before heading back to TouVelle. In all, the trip lasted about three hours, at a cost of $69 per adult.

Out on the water, someone asked Dyer about the opposition to tour boats.

“As long as everybody’s polite and gets along, we can all use it,” he said.

Oregon’s Kitchen Table, a state consultant, is surveying Jackson County residents and river visitors about their views and use of the river. A report is due out in August. To take the survey, go to tinyurl.com/okt-upperrogue-survey.