The heavy rains in December and January resulted in some rivers in Southern Nevada and nearby areas reaching their highest-ever recorded flows, U.S. Geological Survey hydrologists said Wednesday.
The flooding destroyed some of the agency's instruments designed to guage the intensity of the flows.
Hydrologist Jon Wilson said the floods damaged or destroyed instrument stations on the Virgin and Muddy rivers and on the Beaver Dam and Meadow Valley washes, all of which ultimately feed into northeast Clark County.
The agency said it recorded peak flows on the washes and the Virgin River, Meadow Valley and Beaver Dam washes, but an estimate of the flow from the Muddy River was less than a third of the previous record set after severe thunderstorms that hit near Glendale in August 1981.
The geological survey estimated that the Virgin River's flooding was a "100-year flood," meaning such a flow would typically only occur once every 100 years. The floods on the Muddy River and Meadow Valley Wash were of the type that would be expected about once every 25 years, the agency estimated.
A team of federal and state officials are in Clark County surveying damage left in the wake of floods that inundated homes in rural areas last week.
The flooding, an avalanche at Mount Charleston and the washout of the pipeline from Southern California bringing fuel for cars and aircraft teamed up to hit the county with a triple whammy, County Manager Thom Reilly told the Clark County Commission Wednesday.
"I proclaimed a state of emergency effective Jan. 11," Reilly said. "That emergency condition remains in effect."
County officials cited a number of reasons why the declaration of emergency should not yet be lifted. Don Burnette, Clark County chief administrative officer, said the emergency declaration should remain in place while federal, state and local officials evaluate the damages from last week's weather conditions.
While the emergency exists, the county has at least a chance to receive reimbursement for its work from state and federal agencies, Burnette said.
Other concerns are more practical than financial, or a mixture of the two.
"The avalanche danger is covered in the emergency declaration, and that threat has not gone away," Burnette said. "There are well-meaning residents driving over exposed infrastructure in Overton that could sustain damage. Repairs could be made under the emergency and the county reimbursed for the costs.
"If we terminate the emergency, we are saying that our resources can cope with problems caused by the flooding or avalanche," he said. "Just as we found out today, two days after the fact, about the sewage issue coming from Utah, there are likely some unknown problems that will be uncovered over time."
County officials said 22 agencies responded to the unusual confluence of three weather-related events. Reilly said county officials are working with the region's congressional delegation to find federal funding to respond to the crisis.
One piece of good news: The avalanches at Mount Charleston did not do any permanent damage to public infrastructure. Some bad news was that the gas pipeline appears to be a continuing problem.
"This is the third time this year because of weather related issues we have jeopardized gas for cars and fuel for aircraft at the airport," Reilly said.
In Moapa Valley, including Overton and Logandale and Moapa, at least 150 homes were flooded and now have a silt-like mud that covered or destroyed property, including landscaping. Roads and at least one bridge were affected by the flooding, Administrative Services Assistant Director Jim Spinello told the board.
Two golf courses in Mesquite were among the businesses that suffered in the flooding of the Virgin River, Spinello said. Mesquite's phone system also had intermittent problems that extended through last weekend and Martin Luther King Jr. Day. Callers were able to call within Mesquite but could not reach outside lines, Spinello said.
During the four-day event, which ended Friday, the Muddy and Virgin rivers drained water from an area covering more than 8,000 square miles, an area larger than Clark County and about the size of New Jersey.
Damage assessment teams walked through the flood-ravaged communities in Southern Nevada on Wednesday.
"We literally knocked on people's doors and talked them about their damage," said Dan Burns, director of communications for Lt. Gov. Lorraine Hunt who accompanied the team in Overton.
Gov. Kenny Guinn said these assessments are the first step toward determining whether federal and state disaster assistance programs will be made available."
Burns, who was assigned to the detail, said preliminary damage estimates may be made by the end of the week. The teams are looking at how much it will cost to return the communities to the shape they were in before the flooding.
The teams had visited Mount Charleston on Tuesday to check avalanche damage, and a team was scheduled to be in Caliente today.
The teams, composed of state and federal officials, are looking at not only homes but public facilities such as streets, sewers and public building.
Based on the reports from these teams, Guinn will determine whether to recommend a disaster designation for the areas. Then it will be up to the federal government to make a final decision.
If the area is declared a disaster area, than it would open the door to federal grants and SBA low interest loans, Burns said.
Michele McNeil-Candee, staff information officer for the state Division of Emergency Management, said "so much depends on the assessment."
The governor said he is "confident the assessments made by the teams will provide the necessary information so that the maximum assistance will be made available to our communities in need."
Meanwhile, the state Department of Wildlife said there will be a controlled release of about 100 acre-feet of water from the Beaver Dam State Park east of Caliente today. Department officials said the dam is not in imminent danger of failure, but additional rainfall could threaten its stability.
The department said the state engineer's office considered the dam a high hazard because of the flooding. The top of the dam was damaged slightly and water seeps are now evidence across the dam face.
The nearest community in the path of the release of water is Beaver Dam in Arizona.
archive