Utah’s Flooding: The Flood of 83’s Revenge

Utah’s snowpack this year was undoubtedly surprising. Each storm seemed to out-do the last. With roads closing down, avalanches clouding the canyons, and skiers jumping for joy, it was a winter to remember. As we roll into the warmer seasons, the snow we once prayed for might cause us more harm than good. Inevitably melting at a rapid pace and flooding surrounding areas. 

The Central Wasatch Mountains are the source of water for much of the Salt Lake Valley. Each year we rely on the canyons’ snowpack for 95% of our water (see visual below) (2). We also store excess water in reservoirs for dry seasons. This past winter, resorts in Little Cottonwood Canyon, and across the Central Wasatch, received over 800 inches of snow (11). Utah hasn’t had snowfall like this since the season of 1982-1983. 

Long-time residents of Utah continuously remark the similarities of the two winters, as well as the infamous aftermath – the Flood of 1983. 

The Great Flood of 1983 

After receiving hundreds of inches of snowfall the winter of 1982-1983, Utahns saw the aftermath unfold in late April. A “40-foot hole” was exposed on the Emigration Canyon road (3). There was a spur of panic as more mudslides and damage stretched throughout the Wasatch. Salt Lake City (SLC) Mayor Ted Wilson called a state of emergency on May 26, 1983 (5). Eastern canyons and reservoirs overflowed as they rushed the Salt Lake Valley. Despite the effort to pile sandbags, many parts of the region flooded.

On May 29, 1983, City Creek overflowed and stretched to Downtown SLC. Thousands of volunteers were called to help sandbag State Street where the water would be diverted onto 800 South and 1300 South then into the Jordan River (4). City officials and engineers soon went to work to build bridges and make life more normal, despite the circumstances. People across the region traveled to marvel at the “State Street River” (4). In fact, the amount of water was so great that people were kayaking and floating in the flood (see below).

The Flood of 1983 taught us that extreme weather can have consequences we’ve never seen before. It’s been years since Utah had storms and floods similar to 1983. Now in 2023, we are dealing with the same fears as before. 

Current Flooding

Flooding in 2023 seems to be mirroring that of its predecessor. The sudden rush of snowmelt enveloped the Salt Lake Valley. In mid-April, Utah Governor Spencer Cox declared a state of emergency as increasing landslides and flooding occurred (6). Over a million sandbags and funds have dispersed throughout the region since then (5). Citizens have also been provided flood warnings as well as advisories in order to stay safe. 

In May, the Utah Department of Natural Resources asked the State legislature for an extension of the State of Emergency (1). This came after assessing the remaining amount of snowpack left to melt, and expressing concern for potential damage. Rising temperatures means larger quantities of water rushing down the canyon.

Damage

There are a number of concerns regarding melting snowpack. Something that isn’t discussed enough is soil erosion and high saturation levels (1). Saturated soil means more potential for disastrous landslides in both the canyons and suburban areas. We’ve seen various occurrences of avalanches and mudslides this past season in Little Cottonwood Canyon (LCC). Many barricaded the road leaving dozens of people stranded for days at cabins or the regional ski resorts, Alta and Snowbird.

 

Debris from landslides is another hazard. Due to the large amount of snowpack, the massive avalanches took out many rocks and trees. Debri stretched to the LCC creek which can not only cause build up, but also pollute watersheds and negatively impact wildlife habitat.

 

The ever present hazards can be dealt with as they come. Reservoir managers and city officials are continuously working to prevent further damage. However, we still have more rainfall accumulation through the summer storms that will push boundaries. 

 

 

 

 

 

 

Summer Storms

Utah’s past few weeks of summer have seen a surprising amount of storms. With mornings starting out sunny, and closing the day with clouded skies. Much of our snowmelt has been topped off with additional precipitation, adding onto current flooding. This summer, however, is the start of a new era as the El Nino season has begun and La Nina is no more.

El Nino and La Nina are cyclical climate patterns that dictate heat and precipitation across the globe. For the United States, an El Nino season means rising temperatures and rainfall near the lower Pacific Ocean (8). Utah will see rising temperatures but less precipitation. Although this prevents further accumulation of water, it heightens the rate of snowmelt.

Each El Nino season is different from the last. Some years we’ve had average rainfall, others have had more. We can look back to a similar transition during the summer of 1983. Utah’s winter closed that year to the end of its La Nina season. Summer 1984 involved a massive amount of flooding. Only time will tell if our next cyclical season will be similar. 

 

 

 

 

 

 

 

 

 

 

How to Prepare

The snowpack, flooding, and memories from 1983, make Utah’s current situation seem daunting. Where you live impacts your concern for the flooding. Some Utah residents pay no attention to the potential damage. Others stock up with sandbags and barricades. It’s important to not only stay informed, but know the potential risks.

Here is a list of resources on how to prepare for the worst, and more information on flooding:

• Salt Lake City Flooding Events and sandbag resources – https://www.slc.gov/em/2023/04/17/2023-salt-lake-city-flooding-events/ 
• BeReady – https://beready.utah.gov/utah-hazards/flood/ 
• Salt Lake County Flood and Floodplain Map – https://www.arcgis.com/apps/instant/interactivelegend/index.html?appid=988696c93c964a0695a4a319c793102f&locale=en 
• FEMA Flood Map Service Center – https://msc.fema.gov/portal/home 
• Utah Department of Natural Resources Info on Flooding Hazards – https://geology.utah.gov/hazards/flooding/ 
• Utah Department of Natural Resources Info on Landslides – https://geology.utah.gov/hazards/landslides/ 

 

For more information on Utah flooding and soil erosion visit our Environmental Dashboard

 

Written by Mia McNeil

Sources:

1.  https://www.ksl.com/article/50646458/why-utahs-flooding-landslide-risks-are-beginning-to-pick-up-again 
2. https://water.utah.gov/snowpack/ 
3.   https://www.saltlakemagazine.com/utah-flood-of-1983/ 
4. https://www.abc4.com/news/wasatch-front/40-years-ago-the-floods-of-1983-and-salt-lake-citys-state-street-river/amp/ 
5. https://www.ksl.com/article/50624354/gov-cox-declares-state-of-emergency-over-snowmelt-flooding-landslides-in-utah
6. https://www.ksl.com/article/50646458/why-utahs-flooding-landslide-risks-are-beginning-to-pick-up-again 
7. https://collections.lib.utah.edu/search?q=flood+of+1983&gallery=1&facet_type_t=%22Image%2FStillImage%22#g15 
8. https://www.kuer.org/health-science-environment/2023-05-08/what-would-an-el-nino-mean-for-utah-this-summer 
9. https://cwc.utah.gov/environmental-dashboard/ 
10.  https://arcg.is/1Xuj4C 
11. https://www.skiutah.com/members/snowbird/snowreport 
12. https://cwc.utah.gov/environmental-dashboard/water/reservoir-storage/