BOARD00126

• Board Meeting Date: 3/16/2004
• Description: WSP Section - Request for Expenditure from Litigation Fund for Kansas v. Colorado Costs
• Board Meetings - Doc Type: Memo

Arkansas River Compact Compliance
Division of Water ResourceS

.

Introduction
This request is for up to $750,000 to provide for additional activities to implement the findings in the Fourth Report
(October, 2003) of Special Master Arthur Littleworth, who was appointed by the U.S, Supreme Court to oversee and
make recommendations on the resolution of the KS v CO litigation conceming Colorado's violation of the Arkansas
River Compact. Four general areas have been identified into which tasks required to implement or support the
findings of the Special Master in his fourth report have been classified, We believe that the tasks required to comply
with the findings of the Special Master in his Fourth Report, and described in this request, need to be initiated at the
beginning of FY 2004-05 so that the results of these tasks can indicate whether the AMENDED RULES AND
REGULATIONS GOVERNING THE DIVERSION AND USE OF TRJBUTARY GROUND WATER IN THE ARKANSAS RIVER
BASIN, COLORADO ("Use Rules") approved in Case No, 95CW211 in the Division 2 Water Court need to be
modified prior to the end of Colorado's first ten year compact compliance evaluation for the period 1997-2006,
These projects, which will take at least three years to complete, must be initiated by July of 2004 in order to begin
producing results that can be used before the end of 2006,

Backl!round
The State of Kansas filed a lawsuit in the United States Supreme Court against the State of Colorado in 1985, One
of Kansas' complaints was that Colorado had violated provisions of the Arkansas River Compact by allowing post
compact (after 1948) well pumping in Colorado that had diminished flows that Kansas is entitled to under provisions
of the Compact. In May of 1995, the Supreme Court affirmed a Special Master's finding that the post-compact well
pumping in Colorado had depleted usable Stateline flows in violation of the Compact. In response to the Supreme
Court decision, the State Engineer adopted two sets of Rules and Regulations, In 1994, the State Engineer
promulgated the Arkansas Measurement Rules, requiring well users in the valley to measure and provide
information about amounts of water being pumped, In June 1996, rules and regulations adopted by the State
Engineer and approved by the Colorado Water Court became effective to bring wells into compliance with the
Arkansas River Compact, These rules ("Use Rules") restrict pumping of ground water from most wells in the valley .
unless the well user is included in an approved water replacement plan or a decreed plan for augmentation,

The Special Master's Fourth Report provides his lmdings concerning the issues covered in the trial proceedings
during the final segment of the trial, which began on June 24, 2002 and was completed on January 17,2003, The
issues covered in the report, which are relevant to this request, are:
1. Whether there were additional depletions to usable Stateline flows for the period 1997-99, Total depletions for
the period 1950-96 had been previously determined to be 428,005 acre-feet.
2, Whether Colorado's Measurement Rules for the determination of ground water pumping are sufficient.
3, Whether numerous changes proposed by both states to the Hydrologic-Institutional (H-I) Model, which is used to
determine depletions to usable Stateline flows, should be made,
4, Whether Colorado's Use Rules, as implemented, are sufficient to ensure compact compliance,
5, How to utilize the H-I Model in the future in order to determine compact compliance,
In his Fourth Report, the Special Master finds that the new administrative rules for wells implemented by the State
Engineer brought Colorado into compliance with the Arkansas River Compact for the period 1997-99, In addition,
he finds that totalizing flow meters are not required to be placed on Colorado wells to ensure compliance with the
Compact. He accepted Colorado's proposal on how to utilize the H-I Model in the future in order to determine
compact compliance, Finally, he accepted some of the changes proposed by both states to the H-I Model, The tasks
related to the implementation of these changes are the subject of this request. Probably the major task involves
changing the method used for calculating crop water use, which is used as an input to the H-I Model. The Special
Master accepted changing the method for calculating crop water use from the widely used and accepted method in
Colorado, called the Blaney-Criddle method, to a more recently developed method called Penman-Monteith, The
importance of this change is that the Penman Monteith method, with the crop coefficients used by the Kansas
experts, calculates higher crop consumptive use for many crops and requires more data and information than the
Blaney-Criddle method in order to be used properly and much of this data and information is not available for many
locations in the Arkansas River Valley and has been inferred from data available at other locations, This lack of
sufficient data specific to the Arkansas River Valley will have a significant impact on the amounts of replacement .
water that will be required from well USers, Colorado's experts testified that without certain adjustments to the
Penman-Monteith method, calculated crop water use would be overestimated, The Special Master was able to find