Flood likelyMay 3, 2017 By Katie Roenigk, Staff Writer
Conditions look ripe to surpass events of 2011, planners say
Emergency management officials are bracing for flooding this weekend in the Wind River Basin due to rising temperatures and high levels of mountain snowpack.
As of Wednesday, the average snow-water equivalent for the basin was 240 percent of median, and snow depths remained at record levels, according to area Snotels.
"There's a lot of snow up there," Fremont County emergency management coordinator Kathi Metzler said Wednesday. "We stepped it up a little bit for this."
Her agency has dealt with flooding in recent years, and even in recent months, but Metzler said this week emergency management will offer additional resources to help keep residents safe as the rivers rise. For example, Metzler encouraged residents who use Union Wireless can download a Commercial Mobile Alert Service application to receive emergency notifications through an integrated public alert and warning system.
"We'll be using that as one of our communications tools," she said.
Fremont County has published an evacuation plan on its website to let residents know what to expect if they are asked to leave their homes (see sidebar).
Metzler said evacuees should try to stay with friends, relatives, or in local motels if possible, as her agency will only open an evacuation shelter if necessary.
"Make arrangements if you've got a prone area you're used to flooding in," she said, adding, "Please take your pets."
Spots that saw flooding in 2010 and 2011 are likely to be impacted again, Metzler continued. A press release Wednesday forecast a peak flow of 2,100-2,500 cubic feet per second for the Wind River at Dubois - higher than the 2011 peak flow amounts.
Amounts on other major drainages are predicted to be equal to 2010 and 2011.
"You need to be vigilant to changing conditions," Metzler said. "Private landowners should be performing mitigation efforts on their property to protect themselves."
Fremont County Fire Protection District chief Craig Haslam suggested the chronic flooding could merit long-term changes for some residents.
"If you've been flooded for the last 10 years ... you maybe ought to think about packing your bags and leaving," he said.
Metzler noted that emergency service agencies in the county will not assist with mitigation efforts and will only respond to life safety incidents that threaten the community.
"No county equipment will be used to protect private property," Metzler said in a press release Wednesday. "Only critical infrastructure property of the county will be protected by county equipment."
Anyone who wants sandbags can pick them up during normal business hours - typically 7 a.m. to 3:30 p.m. Mondays through Fridays - at the Fremont County Road and Bridge shops at 4421 Skyline Ave. Riverton, 856-8122, and 1580 U.S. Hwy. 287 in Lander, 332-2984.
Citizens must provide their own sand or fill material.
"We have bags available; it's your responsibility to come get them and fill them," Fremont County Commission chairman Travis Becker saidTuesday.
Sandbagging efforts in Hudson have been under way for weeks, but Becker said he's seen too many at-risk homes going unprotected elsewhere in the county.
"I don't know why they're not getting the message," he said. "Private citizens are responsible for taking care of their private property."
No more than 1,000 unfilled sandbags will be given to each address, 500 at a time. Metzler said there are 80,000 sandbags available, and distribution is only limited to 1,000 to prevent people from stockpiling materials.
A press release Wednesday indicated areas that may be affected by high water this weekend include the Little Wind River, the Big Wind River, the Sweetwater River, tributaries of the Middle Popo Agie River affecting Lander, the Little Popo Agie River affecting Hudson, and the North Fork of the Little Wind River affecting the Fort Washakie area.
Metzler said pre-emptive work is being done in Lander as well as in Hudson to help keep public infrastructure impacts to a minimum.
Her agency is assisting with the logistics involved in erecting a barrier wall along Fremont Street in Lander that will divert flood waters away from local roadways and back into area streams.
Initially, Lander fire administrator Nick Hudson said, the city planned to start constructing the barrier in mid-May, but because the upcoming rise in temperatures should activate flooding before then, officials began working with the Wind River Job Corps on the project Tuesday.
Lander streets department director Lance Hopkin said the barrier will run from Fifth Street back to the river along Fremont Street.
"It will be up through the flood season, which we are hoping would be over by the middle to the end of June," Hopkin said.
City crews are also cleaning out storm sewer piping and inlets and trying to remove debris from waterways that could create problems at bridges.
Third Street will remain open until actual flooding is observed.
A weather report last month estimated flood waters could flow at 3,500-4,000 CFS in Lander. To put that in perspective, Hudson said the flood of 2010 saw water flowing at 3,900 CFS. Since then, however, the city has improved its readiness for this type of flood, Hudson said.
In 2010, for example, parts of the Middle Fork of the Popo Agie River saw a great deal of damage to infrastructure along with residential damage due to flooding. Some of those portions of the river have since been widened by 30-50 feet in order to handle more flood waters.
Hudson added that, in 2010, Lander was not able to take every precaution in advance of the flood, so the impacts of the event were greater than they might have been otherwise. Before 2010, Metzler pointed out, the region had been in drought for decades.
"A lot of the people (had) never seen water like this before," she said. "(Now) we're trying to ... get people prepared."
82 on Saturday
She asked residents to stay informed about changing weather patterns and sudden warm-ups that will lead to rising waters. Highs in Riverton are expected to reach 72 degrees Thursday and continue to climb through the weekend, hitting 82 degrees Saturday, according to the National Weather Service.
A report from NWS hydrologist Jim Fahey indicates the warm-up in the basin translates to temperatures in the mid-50s to near 60 degrees in the mountains above 9,000 feet.
Temperatures will stabilize by Sunday, but local forecasters said clouds will roll in to drop rain on the softened mountain snowpack.
"(That's) not a good scenario - if you get three days or so of warming then get rain," NWS meteorologist Paul Skrbac said Tuesday. "A lot (of the snow) will melt and run off."
A hydrologic outlook Tuesday warned that warm basin temperatures will cause steady rises in small creeks and streams Friday afternoon through Sunday afternoon.
"Snowmelt runoff into small streams and creeks will drastically increase," Fahey wrote in the report. "Tributary creeks and streams may reach bank full by Saturday evening through Sunday morning (and) minor flooding of low lying areas is possible."
Main-stem rivers will see "noticeable rises" by Sunday morning, he continued, with additional rises possible Monday, though levels will remain below flood stage.
For further information, contact the Fremont County Emergency Management Agency at 307-856-2374.
Staff writers Kelli Ameling and Daniel Bendtsen contributed to this report.