A tractor sits partially submerged in a field after flooding along the South Platte River in Weld County, Colorado near Greeley, on September 14, 2013. A days-long rush of water from higher ground turned parts of Colorado's expansive eastern plains into muddy swamps. (AP Photo/John Wark)

A raging waterfall destroys a bridge along Highway 34 toward Estes Park, Colorado, as flooding devastates the Front Range and thousands were forced to evacuate, on September 13, 2013. (AP Photo/Colorado Heli-Ops, Dennis Pierce) #

This aerial photo shows a waterfall at flood stage along Highway 34 near Estes Park, Colorado, on September 13, 2013.(AP Photo/Colorado Heli-Ops, Dennis Pierce) #

Boulder Creek roils at high speed after days of record rain and flooding, at the base of Boulder Canyon, on September 13, 2013 in Boulder, Colorado. (AP Photo/Brennan Linsley) #

A flood-affected area of northern Colorado along the Big Thompson River which has been declared a federal disaster area, on September 14, 2013. (Reuters/Capt. Darin Overstreet/U.S. Air National Guard) #

A field of parked cars and trucks sits partially submerged near Greeley, Colorado, on September 14, 2013, as debris-filled rivers flooded into towns and farms miles from the Rockies. (AP Photo/John Wark) #

Cattle find dry ground near Fort Collins, Colorado, on September 13, 2013. (AP Photo/Colorado Heli-Ops, Dennis Pierce) #

Culverts and a boat are piled up after a flash flood in Coal Creek destroyed bridges near Golden, Colorado, on September 12, 2013. (Reuters/Rick Wilking) #

A home and car are stranded after a flash flood in Coal Creek destroyed the bridge near Golden, Colorado, on September 12, 2013. (Reuters/Rick Wilking) #

A farm house, surrounded by flood waters along the South Platte River near Greenley, Colorado, on September 14, 2013. (Reuters/John Wark) #

Residents and children from Cal-Wood Education Center in Jamestown, Colorado await a rescue helicopter flown by the U.S. Air National Guard after severe flooding shut down major roads leading out of town in this September 14, 2013 photo. (Reuters/U.S. Air National Guard/Staff Sgt. Nicole Manzanares) #

Children from Cal-Wood Education Center in Jamestown, Colorado board a rescue helicopter flown by the U.S. Air National Guard, on September 14, 2013. (Reuters/U.S. Air National Guard/Staff Sgt. Nicole Manzanares) #

A couple on an ATV turn around at the edge of a flooded road in La Salle, Colorado, on September 14, 2013. The Sanchez family has lived there for 11 years and said they've never seen anything even close to this level of flooding in the area. (Marc Piscotty/Getty Images) #

A deer jumps over the sidewalk while moving through a flood damaged area in Boulder, Colorado, on September 13, 2013. (Reuters/Mark Leffingwell) #

Pro mountain biker Joey Schusler tests his skills along Canyon Boulevard in Boulder, Colorado, on September 12, 2013. (Dana Romanoff/Getty Images) #

Zoe Kang (right), 11, and Madison Hawk, 11, play in North Boulder Park in Boulder, Colorado, on September 12, 2013. (Dana Romanoff/Getty Images) #

Flood-damaged train tracks in Milliken, Colorado, on September 14, 2013. (AP Photo/David Martin) #

Cars lay mired in mud deposited by floods in Lyons, Colorado, on September 13, 2013. Days of heavy rains and flash floods which washed out the town's bridges and destroyed the electrical and sanitation infrastructure have left many Lyons residents stranded with minimal access to help, and sectioned off the town into several pieces not reachable from each other. (AP Photo/Brennan Linsley) #

Residents look at the damage along Topaz Street September 13, 2013 in Boulder, Colorado. (Marc Piscotty/Getty Images) #

Don DeGraff and his niece Julie DeGraff, both of La Salle, Colorado, carry valuable items out of their home, on September 14, 2013. Don said he already plans to rebuild adding, "we built it from nothing and we'll do it again." (Marc Piscotty/Getty Images) #

Homes in a residential neighborhood in Longmont, Colorado, submerged as flooding continues to devastate the Front Range, on September 13, 2013. (AP Photo/John Wark) #

Matthew Messner looks for a way to cross where water has over flowed the sidewalk from heavy rains in Boulder, Colorado, on September 12, 2013. (Reuters/Mark Leffingwell) #

A residential neighborhood and connecting road in Lyons, Colorado, are cut in two by floodwaters, on September 13, 2013. (AP Photo/John Wark) #

Chris Rodes helps Fred Rob salvage a friend's belongings after floods left homes and infrastructure in a shambles, in Lyons, Colorado, on September 13, 2013. (AP Photo/Brennan Linsley) #

Fred Rob sits in the doorway of his home, destroyed by floods in Lyons, Colorado, on September 13, 2013. (AP Photo/Brennan Linsley) #

A resident rides down Main Street with his dog in Jamestown, Colorado, after a flash flood destroyed much of the town, on September 14, 2013. (Reuters/Rick Wilking) #

A destroyed house with some furniture still intact inside, in Jamestown, Colorado, after a flash flood destroyed much of the town, on September 14, 2013. (Reuters/Rick Wilking) #

A group of trailers are smashed together at a storage site near Greeley, Colorado, on September 14, 2013, as debris-filled rivers flooded into towns and farms miles from the Rockies. (AP Photo/John Wark) #

Farm buildings stand in fields submerged by flooding along the South Platte River in Weld County, Colorado, near Greeley, on September 14, 2013. (AP Photo/John Wark) #

Members of the Rocky Mountain Rescue Group and a resident relax on Main Street in Jamestown, Colorado, after a flash flood destroyed much of the town, on September 14, 2013. (Reuters/Rick Wilking) #

Dakota Walters shovels mud and debris at her aunt and uncle's home on Qualla Drive after their basement was flooded with 8-feet of water in Boulder, Colorado, on September 14, 2013. (Reuters/Mark Leffingwell) #

Allison Wold of Denver, Colorado and her nephew, Jack Wold, look at a flooded ranch home with John Brinckerhoff, also of Denver, after heavy flooding near Dearfield, Colorado, on September 14, 2013. They were trying to cross County Road 87 to get to some family property but couldn't because of the flooding. (Marc Piscotty/Getty Images) #