Problem No. 5 with the Republican River Model is Ignored Elements.
Kansas State Scientist, James Koelliker, says 60 to 80 percent of the stream flow depletion in western Kansas is caused by conservation practices such as terraces, minimum till, and retention ponds. While the study is watershed specific, almost identical conditions exist in Nebraska. In fact, Koelliker has tested his model on the Republican River Basin, including the Nebraska portion.
Koelliker has created a table and formula that allow one to calculate the effect on stream flow based on location and type of crop or vegetation.
The table shows 44 different types of crop or range conditions for various Kansas communities.
The Koelliker study shows that conservation practices in Northwest Kansas have reduced the amount of water flowing into streams and reservoirs due to flood events by as much as 50 percent. He compares precipitation events in 1951-52 to similar events in 1993-94 and shows that terraces and retention ponds have dramatically reduced the expected runoff.
This increased retention of water on the land where the precipitation fell has resulted in more water being available to plants.
According to the USDA, this retained water is responsible for 40 percent of the increase in yields that have been seen in dry land wheat crops since the 1930s. The other 60 percent of the increase has been the result of genetic improvements.
The problem is that the Model intentionally ignores the effects of these conservation practices. Ann Bleed, former director of the Nebraska DNR, said that the effects of conservation were intentionally excluded from the Model because the policymakers did not want anyone to measure the impact and have an incentive to reduce conservation.
The fear was that if people knew how much of an effect there was, there would be a desire to remove conservation practices.
The effect of this is that water captured by conservation and whose timing to the stream is delayed or prevented is reassigned to something else in order to make the Model balance. That something else is groundwater irrigation, thus exaggerating the effect of irrigation and overestimating the benefits to the stream when irrigation is reduced.
To fix this would require the agreement of all three states. As Kansas will not agree to this change, it will require that Nebraska ask the US Supreme Court to correct the problem when the case returns to the Court in the next year or two. This is a decision to be made by the Nebraska governor or attorney general.
If they choose not to act on this, then the Model will continue to fail to accurately measure the causes of the problem and the benefits of reduced allocations.
Again, documentation and graphs are available on the WaterClaim site.