The Threat of Flooding in Manitou Springs

Throughout its history, the economy of Manitou Springs has been based almost exclusively on tourism. Manitou Springs’ dependence on a summer tourist economy relates to the issue of floodplain management in three important ways.

First, the flood hazard and tourism both peak at the same time of year. “Flash floods are most likely to occur in the late afternoon or early evening from late spring to early fall; at those times more tourists and visitors are in the floodplain” (Downing,1977a). Provisions must be made in contingency plans which allow for this increase in population.

Second, although residents may be aware of the flood threat, it should be assumed that visitors to the area are unaware of the potential hazard.

And, third, when a flood does occur, the overall economy of the city will be affected. Manitou’s almost exclusive reliance on the tourist trade suggests that the large scale disruption resulting from a major flood would be especially evident, as “dependence on one major source of revenue leaves the town vulnerable to fluctuations in the industry” (Community Renewal Associates, 1977). The very attractions that lead tourists to Manitou Springs are predominantly in the most hazardous floodplain areas.

The Source of the Problem
Fountain Creek and its tributaries have been extensively developed along the floodplain with residential, commercial and industrial buildings built next to, and in many cases, over the channel. This is especially true in the main business district of Manitou Springs where many businesses are established along or over Fountain Creek. It is also apparent along Ruxton Creek where residential and commercial buildings are built along or over the narrow channel. The flow from Williams Canon has been channelized to flow in a culvert along Canon Avenue with residential buildings occupying the floodplain. The culvert is designed to only carry minimal flow so the channelization is ineffective. The municipal building and fire station are situated along Fountain Creek with building supports extending into the creek.

Floodflow Obstructions
One of the major problems in passing floodflows is the presence of natural and man-made obstructions within the floodways. These obstructions lead to the formation of dams which, in turn, cause higher backwater depths, increased overbank flooding, and, when they fail, surges in floodflows and increased debris battering.

Natural obstructions to floodflow within the Manitou Springs area occur when trees, brush and other vegetation clog the channel.

There are a variety of obstructions built within the Manitou Springs area with stone arch bridges, utility pipelines, wooden footbridges and even buildings spanning the creek channels in numerous locations. Much of this material, especially the small wooden foot bridges, can be expected to be washed away to form debris dams farther downstream. Other restrictions to floodflows are the many building foundations and supports which extend into and over the channel.

Public Awareness
Public awareness and public education are needed in order for the residents of Manitou Springs to have a realistic perception of the hazards which face them. Local authorities should implement a modest education program concerning the flash flood potential.

Community awareness through public education is vital to reduce the flood threat. Public education is a key to saving lives in a flash flood as the short lead time requires quick, positive action. Many tools maybe used to increase the level of awareness including the following options:

  • Showing the Manitou Springs flash flood scenario (the slide show is available at the public library)
  • Signs can be installed identifying the flood threat
  • Evacuation routes can be marked with 100 year flood elevations, and historical high water marks
  • Pamphlets can be prepared and sent to residents and business owners
  • Workshops can be held to maintain a high level of preparedness

Floodproofing
Where economically feasible, building owners should be encouraged to floodproof their structures in a manner compatible with the building’s architecture and historic character. For example, exterior walls could be reinforced with concrete on the inside of the building so as not to alter its outer appearance. Display windows could be protected by various types of flood shields. The Colorado Water Conservation Board’s Colorado Flood-Proofing Manual provides specific examples of various types of floodproofing as well as cost/benefit analyses.

Want to see this story played out live? Check out this video from the Colorado Springs Gazette.

Preparing in advance can save the community and the lives of its citizens.

Courtesy of Dr. Eve Gruntfest
Professor Emerita of Geography & Environmental Studies
University of Colorado Colorado Springs

 

This information was originally published in 1985 as part of a larger study entitled “Manitou Springs Flood Hazard Mitigation Plan.”