SPRINGDALE — Several matters were discussed Wednesday evening at the Springdale City Council meeting pertaining to a possible future obstruction to the Virgin River and the eradication of invasive species.

Wayne Hamilton presented research findings regarding the east landslide area. What started attracting attention in 2006 was the fracturing and slipping of rocks in the area below Watchman. After observing a 2006 Google image of the area, Hamilton said he saw a fresh fracture scar near a sand delta that is over 100,000 years old. He set up motion sensors to inspect the speed of downhill slide occurring in this section of the hill.

“In the first month, I measured 3 millimeters of movement in the downhill direction near the old water tank hill,” he said.

This area was once used to irrigate alfalfa, and there is evidence the area has experienced a major land shift. Hamilton said he found an outcrop of chinle clay that might help explain the past events, though his most significant piece of evidence comes from a sample of a dead tree that grew out of the side of the hill.

Hamilton pointed out the angle at which the tree protruded from the slope. First, the trunk shows signs of vertical growth and then bends at a 30-degree angle. The trunk extends again and then reveals a  20-degree angle. After cutting a sample section from the tree, Hamilton said he counted 150 rings and found sections of thicker rings showing signs of extensive stress. While the threat is not as immediate as it is in another section of land located behind Tribal Arts, he said the potential consequences should be considered.

“If this piece of land comes down in a big clump, it would dam the river,” he said.

“Watch it but don’t lose sleep over it,” Springdale Mayor Stan Smith said. “If it does move, the plan of action is to get heavy equipment there as soon as possible to breach it.”

Some of the people in the audience joked about the need for flood insurance.

Sara Shaughnessey of the National Park Service presented a request for action regarding Springdale’s support of community education as well as grant proposals for the eradication of Russian olive and tamarisk along the stretch of Virgin River running through Springdale.

The Russian olive and tamarisk eradication project was initiated in Southern Utah in 2005. After eradication projects began throughout St. George and Hurricane, the logical answer to the problem became clear: Water doesn’t flow upstream, it flows downstream, which makes Springdale an essential component in getting a handle on the situation, Shaughnessey said. In order to proceed with the project, the National Park Service is asking for support from the Springdale City Council to acquire grant money and obtain resident participation.

Springdale’s support is essential for obtaining a fair amount of control over these invasive species, Shaughnessey said. Rather than going door to door to get support, establishing an outreach program to involve the greater community will result in a better outcome, she said.

“No one wants to be the first to jump on this kind of project,” she said, “but we like to be proactive rather than reactive.”

Russian olive and tamarisk pose a significant threat to endangered and native species because they are the worst fuel type when it comes to wildfires, Shaughnessey said. This vegetation, when ignited, can produce up to 65-foot-high flames and sterilize the soil.

The process of eradicating tamarisk and Russian olive involves either treating the roots with an herbicide or extracting the root system.

The City Council was in agreement that these invasive species pose a problem and agreed that awareness about the invasive species would be included in the next city newsletter.

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