Jacob Creek: It Was Ten Years Ago This Weekend

Photo by Kathleen Smith, earlier today.

My wife, Kathleen, on her way back from Kansas City, called me ten years ago this weekend with an emotional and chilling call, "there is water going across the Kansas Turnpike, I barely got through it!" Kathleen is usually very collected. I knew something was seriously wrong and called the office. We had warnings out for our clients in the area.

When Kathleen arrived home, she was deeply shaken. By that time, the media was reporting something was seriously wrong on the Turnpike. She told me in the darkness with no lightning she experienced the heaviest rainfall of her life. While driving the segment from Emporia (where she entered the Turnpike) to about 20 miles southwest, she was furiously scanning the radio for flood or other weather information. Nothing. The problem was, once on, there was no place to turn around or stop until the Matfield Green Service Area far past Jacob Creek. She was afraid that if stopped on the side of the road she would be rear-ended because of the near-zero visibility.

While following a semi and simply trying to stay on the road when, suddenly, she found herself in deep water. Praying her car would maintain traction as she drove southwest (far lane, right to left on illustrations below). People in the other lane, on the other side of the Jersey barrier, were out of their cars, wading through waist-deep water, trying to escape.

Kathleen made it through, barely, and for a time, continued to Wichita until stopping at Matfield Green (where the memorial is located) to call me. Just behind her, the Jersey barrier gave way and people and cars were instantly washed downstream. The NCAR COMET program created the illustrations below of what happened. Click any image to enlarge.

Photo of the Jacob Creek valley on the Turnpike looking northeast. Jacob Creek flows right to left.

Kathleen Smith

Illustrations from the National Center for Atmospheric Research:

Water flows from bottom of picture to top. The arrow pointed to a box culvert under the Turnpike (I-35) as torrential rain fell.

As the rain continued to fall, the box culvert could not drain the area quickly enough and the water began to back up.

The water encroached the Turnpike after 9pm and began rising as the Jersey barrier acted as a dam.

Kathleen went through about 9:25-9:27pm in the far lane, traveling from right to left. At 9:29, the barrier gave way. 

When the barrier gave way, the water rushed northwest across the Turnpike carrying the people and autos with them.

Six people were killed, including Mr. Al Larsen who died rescuing people from their trapped cars.

How did this occur?

There were a number of issues involving the radar in Wichita which had (and has) warning responsibility for Chase County, Kansas. Heavy rains had begun two evenings before (Thursday, August 28) which saturated the soil.

There had been a problem with the Wichita radar the morning of Saturday the 30th. It caused the radar to "purge" the rainfall readings of the previous two days. The discontinuity was not noted by some.

A band of tropical rains with little lightning developed over the Kansas Flint Hills and moved only very slowly. Six to eight inches of rain fell. Unfortunately, the radar's signal to rainfall conversion (known as the "Z-R relationship") was set to the normal setting rather than the tropical rain relationship. Below

is an illustration from a paper presented to a National Weather Association about the flood. The radar indicated 2-3 inches during that critical period rather than the 6-8 inches that actually fell. Thus, no flash flood warning was issued. Frustratingly, the Topeka National Weather Service radar depicted the event perfectly but its area of warning responsibility ended about 50 yards to the northeast of the flood.

This was not the first fatal flash flood on Jacob Creek. William Least Heat-Moon's outstanding story of Chase County, Kansas, PrairieErth, tells the story of a nearly identical flood (about a mile downstream of where the Turnpike is now located) that washed a wagon of early settlers downstream.

The story of Jacob Creek has been part of meteorologists' training for a number of years. Hopefully, this event uncovered a weakness in the system and it will not occur again.