Governor Spencer Cox said weather will be a determining factor in the risk of flooding across the state.
He was joined by other state officials at a press conference Thursday afternoon. Utah Department of Transportation Executive Director Carlos Braceras said the public should expect more emergencies like the mudslide in Parleys Canyon Thursday morning.
“We expect additional material to keep coming down,” Braceras said. “We have developed response plans for this based on the level of probability and the risk associated with that probability. So, everything from a small amount of material comes down; how do we respond to that? [To] if a large amount of material comes down, how do we shut down the canyon very quickly?”
Braceras said that stretch of Interstate 80 is prone to deep-seeded slides, or “massive Earth movements” in other words. However, he said what happened in Parleys Canyon Thursday morning looked more like a “surface slide” that won’t trigger future slides.
Cox said one of UDOT’s primary focuses at the moment is Little Cottonwood Canyon, where wet avalanches have been frequent as temperatures warm.
He also said Thursday’s cooler temperatures are a good thing.
“Because of the temperatures that are forecast right now, we're not as worried as we might otherwise be,” Cox said. “If you show me three days in the 80s coming up anytime soon, then I'm really going to start to panic in lots of different ways, but if we can keep it in the 60s with cold nights, that also helps.”
National Weather Service hydrologist Glen Merrill said fluctuation between warm and cool days will help. That will prevent the snow from melting and gushing into canyons and communities all at once.
“Over the next two weeks, the outlook looks like a good one,” Merrill said. “We warm up again this weekend into early next week, and then we cool down, lock it up, and then we warm up after that. We don't see any big rain or snow events. So right now, looking forward, we're in good shape.”
Department of Natural Resources Executive Director Joel Ferry compared this spring to 1983, a spring infamous for huge floods in Utah.
He said overall, what’s happening so far this year is better. In 1983, snow continued well into May and the runoff began much later.
“In the '80s, it all came down at once. It heated up really quickly,” Ferry said. “So, what we're hoping for is weather like we're seeing today, where you have three or four days of warm weather, [or] four or five days, and then it cools down. So, the runoff starts, it picks up, but it's going to slow down a little bit, and we're going to ease it through.”
This week, floods and other snowmelt emergencies have already happened in Kamas, Francis, Heber City and other parts of eastern Wasatch County.
“My message to Utahns is twofold,” Cox said. “First, please do what you can right now to prepare. We've had a pause. Now you've seen where the water is coming. So, we have a break in the action. Pay attention to local conditions. Stay away from fast moving rivers and streams. Fill sandbags if you can. Ask for help if you need it.”
More information on flood risk in the Wasatch Back; including hazard maps, sandbag centers, mitigation tips and insurance information; is available here.
