Tourists and truckers were told to prepare for another day of disruptive detours Wednesday around a closed stretch of busy Interstate 15 (I-15) in southern Nevada that crumbled in chunks during intense flash flooding.
Ripples spread from the closure of the main road from Las Vegas to Salt Lake City, as crews began mopping up from Monday's pouring rain and rushing runoff. Water also scoured out part of a main rail freight line and swelled a river so high that a Utah national park was briefly shuttered.
The storm, spawned by seasonal monsoon moisture and the remnants of Tropical Storm Norbert, dumped heavy rain throughout the Southwest and set a single-day rainfall record in Phoenix.
But the sun was out Tuesday in the rural southern Nevada towns of Moapa and Glendale, about 50 miles northeast of Las Vegas.
Convenience store manager Penny Hyde spent a harried day advising motorists who waited through delays and detours to reach Glendale that to get back on I-15 they'd need to take another roundabout route on two-lane state and U.S. highways to Panaca, Nevada, and then to Cedar City, Utah.
"It'll be a couple of hours out of their way," said Hyde, who noted the remnant red mud all around her store.
No damage estimate was immediately available, but Clark County spokeswoman Stacey Welling said officials were preparing to ask county lawmakers next Tuesday for an emergency declaration.
A state disaster assessment team was due in the Moapa and Logandale area on Wednesday to begin determining if the region would qualify for funds from the state.
Officials say large-scale damage was narrowly averted when rushing water nearly overwhelmed the banks of the swollen Muddy and Virgin rivers.
"We saw it right at the cusp and it didn't go over," said Erin Neff, spokeswoman for the Clark County Regional Flood Control District. "It's a near-miss."
A subdivision with about 30 homes flooded in Overton, several miles downstream from Moapa, and Clark County firefighters counted 18 rescues in the area, many involving submerged cars.
"I've been in this area since 1978. We've never had water like that before," said David Muns, a resident of Moapa, where more than four inches of rain fell in two hours.
Transportation officials said the damaged stretch of I-15 near Moapa could be closed for several days for repairs. It usually carries about 20,000 vehicles a day.
Union Pacific Railroad service was suspended while crews repaired track that was undermined and washed out near Moapa. Officials hoped to have the track bed and rails repaired by Wednesday for freight service to resume on the busy Las Vegas-to-Salt Lake City main line.
In southern Utah, rangers at Zion National Park turned away visitors for several hours Tuesday when heavy rain and a surging river made park routes impassable. Mud, debris and a boulder blocked Route 9, the road through the main canyon.
Wet weather also took its toll on neighboring states.
Freeways in Phoenix became small lakes on Monday and rescuers scrambled to get drivers out of inundated cars after more than 3 inches of rain fell.
Cars also were stranded near Palm Springs and in the Coachella Valley in Southern California.
Beneath an I-15 overpass in the Moapa area, police officer Shanan Kelly said he and several construction workers helped rescue a woman who was swept into rushing water from the top of her minivan.
"It was very heroic and awesome," Kelly said.
A Red Cross shelter remained open Tuesday night at a school in Overton.
About 190 people were evacuated from the Moapa Band of Paiutes reservation after tribal officials warned that waters were close to breaching a Muddy River dam.
"We had rivers running through people's yards. But as far as property damage to homes themselves, I think we fared pretty well," said Sherryl Patterson, administrator at the tribal office.
National Weather Service meteorologist Charlotte Dewey warned that any more rain in the Southwest could cause new flooding because the ground was saturated.
Associated Press writers Paul Davenport and Alina Hartounian in Phoenix, and Michelle Price in Salt Lake City contributed to this report. Rindels reported from Las Vegas.