The Colorado Flood 2013

While I was hoping to focus more on flooding and erosion in South Dakota, I feel the flooding in Colorado deserves some attention. Colorado is also special to me as I lived there for six years and many of my grade school friends currently live in or close to the effected areas.

So why did this flood happen? Well there have been several previous floods recorded in these same areas. This would be due mainly to the climate, underlying geology, topography, and vegetation. The climate this time of year is general dry but according to Martin Hoerling from Earth System Research Laboratory in Boulder, the moisture-laden air, moving up from Mexico, was drawn up by the mountains thus turning into rain. This event lasted unusually long in the affected area. Now as we all know the topography in the Rocky Mountains is very steep with narrow canyons. The Geology tends to be solid rock, while the vegetation is mainly coniferous trees and alpine plants. Also due to the recent wildfires in some of the effected areas, the newly growing vegetation would be sparse. All of these factors would lead to very small amounts of rainwater being absorbed creating large amounts of surface overflow. The surface flow would quickly drain to the bottoms of the canyons, picking up intensity as it went. This fast-moving water would wash away most anything in its path, creating the damage and devastation in the mountain towns. The water then reached the point where the canyons opened up to the plains. Many cities are located at these points, so while the water slowed somewhat and spread out, it still caused much damage due to the volume and already saturated ground. (Below are a few pictures from The Denver Post showing the damage.)

This flood reminded me of the Rapid City Flood of 1972. So, I wonder what provisions, if any, will Boulder, Longmont, Loveland, and the other affected cities take to keep this kind of damage, destruction, and death from happening again. I felt Rapid City's decision to create the green space along Rapid Creek was instrumental in saving lives and decreasing property damage from future flood events. Below is a flood map of Boulder. Notice the colored areas showing the 100-year and 500-year floodplains. I find it unsettling that the University of Colorado has student housing within the floodplain. So, hopefully better protection against future events will be put into place.

Photo by Joe Amon/The Denver Post

(Floodwater flowing through a housing area and over a road.)

Photo by Tim Rasmussen/The Denver Post

(Notice how the road was no match for the force of the water.)

Photo by Andy Cross/The Denver Post

(The floodwater easily eroded the soft fertile soil.)

Photo by Andy Cross/The Denver Post

(Notice the amount of debris left by flowing water and mudflows, the house is damaged on the left side. US 34 along the Big Thompson River)

Photo by Andy Cross/The Denver Post

(The fast flowing creek washed away the road but was contained by the rock canyon wall. Swollen Big Thompson River damaging US 34.)

Photo by Andy Cross/The Denver Post

(The shear force of the Big Thompson River. This is at Chasteen's Grove waterfall. Loveland's water treatment plant is on the right side of the picture)

 

Floodplain Map by Oakleafcontracts.com

(Notice where the high school and student housing are located.)

The theme for my first blog in my hydrology class is erosion and flooding effects. Both of these topics cover the force of water. In the summer of 2011 I had several of my family members affected by the flooding on the Missouri River. I was able to watch the process of preparing for the flood, the activity during the flood, and the aftermath after the water receded. I then became curious about learning more about how flooding changes the landscape both good and bad. My family also has a ranch in central South Dakota along the Cheyenne River. Much erosion can be seen along the Cheyenne and on the ranch land draining into the river. Once the topsoil is washed away, it is very difficult for grass to regrow. Water drainage also creates deep washouts that can be difficult for cattle or horses to cross. I am very interested in learning more about good practices to slow the erosion in these critical areas.

I feel a good blog is one that is interesting to read, while providing accurate and useful information. Blogs should not bore you with all the intricate details but summarize the important points. It should be fun and pleasing to the eye. A good blog will keep to it's topic so that followers know what to expect.