ZION NATIONAL PARK — On any given day during the height of the summer visitor season, thousands of people wade and play in the Virgin River at the Narrows in Utah's most popular national park.
Hardy adventurers, too, seek the "other worldly" experience by making the complete 16-mile trek through the Narrows, wading through the rushing water and picking their way over boulders and rocks to gaze at the spectacular sandstone scenery.
"We think a national park where people play in the water is pretty darn important," said Dave Sharrow, hydrologist for Zion National Park.
But there's a threat here, and it has nothing to do with falling rocks or narrow terrain. Levels of E. coli contamination in the river are "off the chart" and far exceed state water quality standards.
That's prompted park officials to issue warnings along with permits to backcountry hikers to avoid contact with the water as much as possible.
"We are concerned that levels of E. coli bacteria that we are finding in the river exceed the state standard for swimming-type recreation," Sharrow said. "And when that happens, the risk of coming down with a disease associated with playing in that water is too high. We would like to protect visitors and get the water cleaned up to the point where we meet the standard."
Walt Baker, director of the Utah Division of Water Quality, said three years of testing from 800 water samples detail levels of E. coli contamination that are "significant and a concern," with rolling averages showing high levels 90 percent of the time.
Amy Dickey, environmental scientist with the state Division of Water Quality, said she's not aware of any reports of people getting sick from the contamination, but Environmental Protection Agency standards say with levels that high, eight out of every 1,000 are at risk.
"Sometimes it won't show up for several days," Dickey said, "and people by then may write it off as the flu."
The culprit is feces — from wildlife, people and from cattle that graze upstream on Bureau of Land Management property and private lands.
The BLM, Division of Water Quality and the Utah Farm Bureau all play a role in solving the problem and will meet next week in Cedar City to search for solutions.
"It is a puzzle. We've put a lot of time and resources into studying the problem," Dickey said.
"I get asked a lot of times, 'Who cares? It is out in the middle of nowhere.' But it is our job to take a closer look, and it is a problem when it is upstream of a national park, where thousands of people are in the water recreating and more who spend the night in the Narrows," she said.
At the bottom end of the Narrows at the riverside walk, there is no limitation on the number of people who can jump in the water, Sharrow said.
"We have documented 2,000 a day, and that was before we had our shuttle buses and parking was limited," he said. "It is probably significantly higher than that. There are a lot of people playing in the water."
The park does limit the number of participants who make the daylong or overnight trek all the way through the Narrows, Sharrow said, curtailing the number of permits issued at any given time.
Still, the impacts go on all season long, with an estimated 5,000 people who go through the Narrows each year.
Upstream, the BLM issues grazing leases to ranchers on land northeast of the park, and private land is also home to cattle.
Sharrow said flood irrigation practices that ultimately wash manure into the river are suspected to be at the root of the contamination, but he said the area is rife with wildlife and, downstream, with people.
"There's a whole lot of animals out there pooping," he said.
To help eliminate one source of the problem, a pit toilet was installed in the summer of 2011 at the trailhead of the Narrows, Dickey said, on BLM land where people start their trek into the park.
"There was fecal matter and toilet paper behind every shrub, bush and tree at the spot," she said, with people relieving themselves prior to reaching the river. "We are happy to say the toilet has been well used."
Tyce Palmer, resource coordinator for the southwest area of the Utah Association of Conservation Districts, has been working with local land owners and state and federal agencies to help mitigate the contamination problem.
"It's a complex watershed, in a pretty steep and narrow remote area," he said. "There might be some cows in there in places where we can do better management on."
Palmer said he was in the area recently and found a cabin with an outhouse that had been erected right over an irrigation ditch, its contents eventually flowing to the river.
"There's definitely a lot of issues up there, not just the old cow," he said.
Dickey said the E. coli levels have been so high they exceed what the state can test for, which earned the river a spot on its watch list for human interaction.
The good news, both Dickey and Sharrow said, is that after Deep Creek meets up with the Virgin River, the contamination is diluted, but some E. coli persists at the park's Temple of the Sinawava.
Both water watchers know the fix won't be an easy one because of the diverse group of interests involved. Sharrow said he's not in the business of telling cattle ranchers how to manage their animals, but he wants to fix the problem.
"It is a remote area. It is not an ideal place to change irrigation practices. You don't have electricity," he said. "You don't have someone living there being able to run and operate the system all the time. It is going to take some time and some creativity to come up with a solution."
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