National Park Rocky Mountain Colorado National Park Service U.S. Department of the Interior Flood! / started to hear a sound like an airplane...there were loud booms...I saw trees crashing over and a wall of water coming down...there was a deafening roar.... Steven Cashman Flood of '82 In mountain environments, weather Human activities also sometimes Thompson Canyon Flood of patterns can change quickly, cause floods. Dams and levees 1976 showed the scouring force turning meandering streams into designed to tame a river or lake of a natural, flash flood. The Flood scouring walls of water or flash can fail. Generally, natural and of '82 or Lawn Lake Dam failure floods. Floods can be natural or unnatural floods are minor was a reminder of the limitations unnatural events, but both occurrences causing little of human engineering. Both flood demonstrate the same awesome damage, but all floods have the events unveiled the shattering force of water. capability to change human lives force of water, and the ability of and the natural landscape. people and nature to rebuild and Natural floods in the mountains recover. can be caused by snowmelt or In Rocky Mountain National Park spring runoff, rainfall mixed with and the surrounding area, two snowmelt, or intense rainfall from major floods have displayed this storms. powerful force of water. The Big BIG THOMPSON CANYON Water levels rose 9 feet above the During the flood, search and FLOOD normal riverbed, cutting away the rescue personnel tried to warn river bank and changing the and assist people in the canyon. The Big Thompson Canyon is river's main channel. Soil, rocks, Some rescue workers lost their located in the foothills east of the trees, homes, and businesses lives trying to save others. town of Estes Park. This canyon, were swept away. Once the water Rescue workers came from local like many in the foothills area, is reached the plains, the water areas and from far away to help characterized by narrow valleys slowed down and spread the people trapped in the canyon. bordered by steep, side slopes debris out for miles. Following the flood, searchers with soil that is highly susceptible continued working for weeks to to erosion. Intense rainfalls can Few flood controls and warning find survivors and to retrieve the oversaturate the soil and overflow systems were in place along the bodies of those who had river banks, creating a flash flood. river. Flood warnings were issued perished. too late for many people in the During the night of July 31,1976 canyon. Others ignored the severe thunderstorms developed warnings altogether. In the over the Big Thompson River confusion, some people tried basin. A large storm system driving up or down the canyon and stalled over the foothills for several were lost in the flood waters. By hours, dumping torrential rains in dawn, 145 people had lost their the upper section of the canyon. In lives in the canyon. Many survived one area of the canyon, 71/2 by climbing to higher ground or inches of rain fell in a 70-minute clinging to trees and rocks. period! Jf^ Printed with Soyoil Ink *M0 on Recycled Paper FLOOD OF '82 As the flood entered the flat valley, Luckily, the Lawn Lake Dam failed the water slowed down and early in the morning before many Lawn Lake is a natural lake quickly deposited the heaviest people were in the park. A trash located in the park's Mummy debris first. Initially, large collector working in Horseshoe range. In the early 1900's, a boulders, weighing up to 452 tons, Park notified emergency 26-foot high earthen dam was were dropped, while lighter personnel. The early notification added to the lake, nearly tripling materials were carried farther allowed emergency personnel to its size. This privately owned dam downstream. The flood waters issue advance warnings of the was one of five dams built prior to spread out and deposited debris pending flood danger. Flood the establishment of Rocky in a fan shape or alluvial fan over warnings were issued inside Mountain National Parkin 1915. 42 acres in size. Rocky Mountain National Park, and in the town of Estes Park and On July 15,1982, at 5:30 a.m., the The flood continued eastward the surrounding area. Lawn Lake Dam failed. On this down the Fall River drainage calm, clear Thursday morning, a towards a second dam. Four Emergency personnel closed 95-foot section of the dam feet of water swept over the roadways and evacuated people breached sending more than 200 17-foot high, concrete Cascade from the flood path. The water million gallons of water down the Dam, causing this dam to fail. level in Lake Estes was lowered Roaring River into the Fall River The new wave of water continued to handle the incoming water. drainage. A 30-foot high wall of on towards the town of Estes The Flood of '82, which traveled water scoured out trees, boulders, Park. Trees, mud, rocks, and six 12 1/2 miles in 3 1/2 hours, and sand from the steep feet of water covered downtown claimed three human lives in mountainside and carried them Estes Park and continued to head Rocky Mountain National Park down to Horseshoe Park. towards the Olympus Dam which and caused over $31 million forms Lake Estes. This dam held damages in the town of Estes and the flood was stopped. Park. RECOVERY The Flood of '82 destroyed some Following the dam failure, the areas while creating new life in remaining private dams inside Powerful flood waters scour out other areas of Rocky Mountain Rocky Mountain National Park channels and deposit the National Park. Visual scars along were removed. The town of Estes material they carry, changing the the alluvial fan and the scoured Park was declared a national landscape in an instant. Both the river remain. Fish and wildlife disaster area and the community Big Thompson Canyon Flood and slowly returned to Horseshoe rebuilt. The Flood of '82 challenged Park. Trees, killed during the nature's and people's ability to flood, provided a new haven for Both natural and unnatural floods recover. cavity nesting birds. Many trees, change the landscape and shrubs and grasses sprouted on people's lives. Floods can be In the Big Thompson Canyon, the alluvial fan, beginning a new destructive while at the same time, recovery started immediately. The cycle of growth. Flood debris creating new areas. Being able to canyon was declared a national created a new lake and wetland recover from these dramatic disaster area and human area, opening up opportunities for events is part of the natural cycle. intervention quickened the pace of waterfowl and returning beaver recovery. Flood warning systems populations. and signs were improved. Areas of the canyon were revegetated and the roadway rebuilt. People began to reoccupy and rebuild. Today, stories about lost loved ones and the courageous efforts of many people in the canyon^ continue tp be tolcU^__>^ "V* .