WMOD00249

• Contract/Permit #: #97-3
• Applicant: Western Kansas Groundwater
• Project Name: Kansas Weather Modification
• Date: 1/1/1997
• Weather Modification - Doc Type: Public Hearing

EVALUATION OF THE WESTERN KANSAS
WEATHER MODIFICATION PROGRAM

INTRODUCTION AND SUMMARY

Weather modification activities began in Western Kansas in 1972 and several cloud seeding
operations were conducted from 1972 through 1978. The centerpiece of weather
modification activities in Kansas is represented by the Western Kansas Weather Modification
Program that has operated from 1975 to the present time under the leadership of the Western
Kansas Groundwater Management District No. 1. The primary objective of the Program has
been to reduce hail dama~e, although a significant effort has also been made to increase
precipitation.

The Western Kansas Weather Modification Program has been solely locally funded with
fmancial support typically ranging between $150,000 and $250,000 per year. State support
for the Program has been limited to the annual issuance of a permit to operate the Program
by the Kansas Water Office.

In late 1993 and early 1994, Keith Lebbin and Wayne Bossen, Managers of Western Kansas
Groundwater Management District No. 1 and Northwest Kansas Groundwater Management
District No.4, respectively, called upon the Kansas Water Office to evaluate the
effectiveness of this Program in order to increase the likelihood that state suppon might be
provided to enhance and/or enlarge the Program. The Kansas Water Office proceeded to
prepare a new subsection of the State Water Plan entitled "The State Role in Weather
Modification" and was directed by the Kansas Water Authority to proceed with an evaluation
of the Program. It was indicated in this new subsection that state support for the Program
would be dependent upon a favorable outcome to the evaluation.

The Western Kansas Weather Modification Program has been evaluated on several previous
occasions by various entities. However, the previous evaluation methodology and/or results
have been viewed as somewhat inconclusive by the Kansas Water Office. The recently
completed evaluation of this Program, by the Kansas Water Office, differed from previous
evaluationS of the Program in the following three significant areas: 1) the general
methodology to be used for conducting the Kansas Water Office evaluation was distributed to
the three Western Kansas Groundwater Management District Managers and was endorsed by
the Managers and the Kansas Water Office, 2) the target area (counties receiving cloud
seeding) consisted of the six counties who had participated in the Program for every year that
was included in the evaluation time period and 3) the control area did not include any
counties that received cloud seeding during any ponion of the evaluation time period.

The precipitation component of the Kansas Water Office evaluation of the Program showed
that precipitation declined by 0.25 inches in the target area from the pre-cloud seeding time
period of 1941 to 1970 to the cloud seeding time period of 1979-1993. This amount of
change in rainfall is well within normal precipitation variation and was determined to be of

1