Two soil experts say crowds at the Boise River Festival and other summer activities could threaten the river they want to celebrate.
Sections of the river's banks have been seriously damaged by "people traffic," according to soil scientists who toured the river recently with an Idaho Statesman reporter."I can't say it's all from the festival, but these areas certainly have been impacted by tromping," Terry Tindall said. "People love these riparian areas. Unfortunately, we can love them to death."
Tindall is a University of Idaho soils specialist who examined the scene of the festival's Night Light Parade, which occurred in late June. About 100,000 people watched the parade from the river's banks.
Accompanying Tindall was Hal Swenson, a U.S. Soil Conservation Service soil scientist. Neither was convinced the impact of the crowds was serious enough to recommend canceling future festivals.
But they warned that without proper controls, festival crowds could undermine the river's aesthetic value and water quality.
Places where natural vegetation has been destroyed "put fair amounts of sediments into the river system," Tindall said. "What they might want to consider is restricting those areas that are more sensitive to erosion and traffic."
"If they could keep the crowds on top of the bank instead of walking or sliding down the banks, it would help as much as anything," Swenson said.
Both men said separating festival damage from longstanding problems is difficult. But they said festival crowds most likely contributed to soil compaction, loss of vegetation and erosion.
"Our main concern is taking care of the river, because that's what we're saluting," festival executive director Steve Schmader said. "We're very concerned about that, and we think we've done a good job of it."
The entry point for the festival's river floats - which also is a jumping off point for people tubing the river - was rated "poor" by the two scientists.
"This area is toast," Tindall said. "This is serious degradation over a period of time. People putting in floats didn't do all this, but it's definitely people traffic."
Also, riparian zones at Park Center, Boise State University, River Run subdivision and city parks lining the river are too narrow to provide adequate erosion and wildlife protection, the experts said.
"There are places where the bank has been cut down as much as a foot by erosion, trails and traffic," he said. "Grass and weeds have replaced the natural riparian vegetation. There are definite signs of tromping and a lot of erosion here. People shouldn't be allowed on these banks."
"During the festival or at any other time," Swenson added.