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"' We both quickly learned that the data necessary to drive good computer models was lacking in the basin. so a lot of assumptions had to be made. and both models had their shortcomings. The area of focus for the modeling efforts ofboth states was the area from Pueblo to the state line. It basically covered the valley fill or alluvial aquifer of the Arkansas River as well as aquifers to the outside of these called bench aquifers or surficial aquifers. Basically, it is an area where there are about 2,000 irrigation wells in existence that have pumped upwards of 250,000 acre-feet (at) of water in certain }'e8I's. The models were set up in a manner to evaluate both the effect of pumping and then turning off certain switches in a model to evaluate the effect of what the river would have seen in the way of additional flows had tbere not been pumping. Where would that water have been diverted? Would the senior surface rights have diverted more, or how much really would have reached the state line? The study period was 1950 to 1985, and both states came down with similar results. It is not surprising. when )'OU think about the hydraulic connection between the alluvial or surficial aquifer and the stream system. If you pmnp grooodwater, and if you consume it in growing crops, you are going to deplete streamflow. That is a fact of physics that you really can't overcome no matter how much you would like to. Both states had similar results, although Kansas' model showed lesser depletions of usable state line flow than Colorado's model, and the Master in his report indicated that he would support using the Kansas model since it showed the lesser depletions and Kansas was the complaining party. He further fO!JIld that the 1973 rules were not effective. In other words, that reduction or curtailment of pmnping to just three days of pumping per week didn't really reduce pumping. in his opinion. In fact, every}'e8I' after 1973 the pumping increased or was greater than the 1973 level of pwnping. In his report which he filed in July of 1994, the Master found, just to reemphasize, that most compact well pwnping did deplete usable state line flows. The 1973 rules were not effective. The augmentation plans that allowed certain wells to pwnp seven days a week were not sufficient in ~ depletions caused by post-compact pumping. There were some offsets but not complete offsets, so he was critical of the augmentation plans that had been approved in the intervening period. Year by}'e8I', the division engineer under the 1973 rules would allow groups, if they submitted a plan, to pwnp seven days a week -- and there was augmentation, but not total augmentation. One of the more limiting determinations of the Special Master was that the 700 existing pre-compact wells could not pwnp unlimited with respect to the compact. His finding was that in the period just prior to the signing of the compact the pwnping averaged about 15,000 afper}'e8I'. Colorado had argued that it could have been as much as 40,000 afper }'e8I' in dry }'earS, and that it should be allowed to pwnp what was necessary based upon the decree of the pre-compact well. The Master put an annual limit not to exceed 15,000 af on those 700 wells, and so one of the responsibilities under the new rules is how to allocate the 15,000 af to those 700 pre-compact wells. You heard from Jim Lochhead just before lOOCh about the Arkansas River Coordinating Committee and how important'it was in bringing together all the diverse interests of the valley. I want to say briefly that the conunittee was, in my opinion, a real success, because the water users, after about three or four months of sparring, sat down aroood the table and for the next six or eight months worked hard on helping develop workable rules and regulations, helping to find solutions on where we could find augmentation water, and generally working together-in a manner I hadn't seen in the Arkansas River Basin in the pasL It is the leadership of those 30 individuals who were willing to meet monthly without compensation, some of them driving from Leadville to Lamar at times just to be public servants, that I think can be credited for the success we had thus far. . I want to take a few minutes to talk about the new rules to let }IOu get a flavor of what we are trying to accomplish, our time lines, and where we are right now. There are two key points that I want you to really understand about these new rules. One is to bring about compact compliance. David Robbins indicated to you that we have no choice. It is the law of the State of Colorado and it is the law of the federal govemmenL It is a compact. We have been fOood to be in violation, by primarily the pwnping of 1500 post-compact wells. The second issue, which I think is just as important, is that we have about 2000 we~s, that may total about 2200, some of them are not always pwnping in a given }'e8I' and affecting senior surface water rights in Colorado. As I indicated, Mr. Kuiper in 1973 started down a path to bring the pwnping by junior wells under control and require augmentation. He was not successful, but we cannot overlook all the infonnation we have developed through the investigations related to the litigation with Kansas. Arkansas River Basin Water Forum 23 "A River of Dreams and Realities"