Restricted Pumping Effects

Effect on the stream caused by turning off varying numbers of irrigation wells

We are not aware of any Model runs that have been done showing the result of turning off 60,000 QR acres and limiting pumping in each district.  Several other things, which are not being done have been modeled but the thing that is being done has not been simulated.  If it has, we are unaware of it and the DNR has not told the NRDs or anyone else about the simulation. 

 In 2004, Ray Supalla from the University of Nebraska was commissioned by a group of power companies, banks, and coops, to do an economic study.  The question asked by this group was what is the economic impact of the various water reduction plans that are being considered.  The DNR had four computer simulations studying this question.  These charts reflect what the DNR was considering in early to mid 2004.

The computer simulation estimates how much water should have reached the spring if an irrigation well had not intercepted it.  This chart shows how much water was intercepted by year.  Remember, the pumping this year may not have an affect on the stream for a number of years.  The simulation computes which future year that affect will happen.

Definition - Consumptive Use - Water that would have been in the stream except for the activity of man.

This chart shows the consumptive use for the Republican River Basin.  The total volume from the 0 axis to the top of the red area is the consumptive use if no changes are made in irrigation practices.  The dips and hills are caused by varying amounts of rain, irrigation evaporation, etc in years past that are just now having an affect on the stream.  If the entire Basin were to reduce irrigation by 10% then the amount of water saved, that would now flow into the stream, would be the difference between the top of the yellow line and the top of the red line.  The effect is minimal in the first several years but grows as time goes by because of the delayed affect.

The Nebraska portion of the Republican River Basin studies done in early 2004.  

The Upper Republican NRD asked the DNR what the affect on the stream would be if all of the Quick Response wells (those within 2.5 miles of the stream) were permanently turned off.  There are 88,000 QR acre in the URNRD.  If all were shut off then this is what the DNR projects would be the increase in the stream.  This study was done in February of 2005. 

The Nebraska portion of the Republican River Basin studies done in early 2004.  

There are some questions about the results the Model shows regarding the affect on the stream if irrigation wells are turned off.  

1. If there are 88,000 QR acres in the URNRD.  Each pumps about 1 acre foot per acre.  This means the QR wells in the URNRD use about 88,000 acre feet of water each year.  If those are all turned off then the Model says the stream will only increase by about 20,000 acre feet per year after three years.  That would imply the Model says that 23% of the water pumped from a typical QR well gets its water from the alluvial area that would have, at some time, been in the stream if it had not been pumped.  That also implies that 77% of the water would never have entered the stream even if it had not been pumped.  Is this correct?

2. Assuming our understanding of what the Model says about the percentage of water being available to the stream is correct, then is this also the same percentage for the entire Basin?

3. If all QR wells in the Nebraska portion of the basin were shut off, then we can infer that the stream would increase its flow by about 23% of what had been pumped by the QR wells.  There are no definitive numbers on the number of QR acres irrigated in the Middle or Lower NRDs. NRD estimates are 88,000 for URNRD, 71,000 for the MRNRD, and 97,500 for the LRNRD.  Tri Basin NRD numbers do not exist.  This would be about 256,000 QR acres and a resulting stream increase of about 59,000 acre feet per year.  This is about half of what the DNR projected in 2004 when they looked at the four reduction scenarios (pink and blue chart above).  Which number is closer to correct, the 2004 estimates or the numbers we derived from the 2005 URNRD Model runs?

4. Why do the NRDs choose to make decisions without knowing the answers to virtually any question dealing on this subject?

What would happen to the stream flow if you shut off all of the upland wells in the URNRD in 2001 and left them off.  According to the DNR Model run the stream flow would increase by the amount shown in this graph.  See the 2nd graph for perspective.

The blue line on the following graph is the same information at the blue on the above graph.  For example, in the year 2014, the basin would have pumped about 500,000 acre feet of water out of the ground.  In the same year there was an increase in the stream flow of about 16,000 acre feet.  Remember the pumping does not have an affect in the year the water is pumped but instead on many years out in the future.  So in reality the water that was not pumped in the year 2001 would cause the stream to increase its flow by a small amount in each of the many future years. After 40 years the DNR reports that 17,319,000 acre feet of water would not have been pumped out of the ground and this would after 40 years cause the stream to have an additional 751,000 acre feet over those 40 years.   To put that in perspective it would be like you giving me about $450,000 a year and I will give you in return $18,800 a year.  Actually almost nothing at first and then more toward the end, just like in the graphs.

In other words, the only way to increase stream flow is to turn off all wells and even then the increase in the stream flow will be minimal.  Those such as the Game and Parks, Tom Osborne, Robert Ambrosek, and Jack Maddox need to consider what they gain in exchange for the cost they pay.  

For every 1000 acre feet not pumped, the NDNR reports indicate that there will be a 1.16 acre feet increase in stream flow.

• 25% reduction of quick response well pumpage in 2001 results in 2.9 AF saved for each 1000 AF not pumped.

• 25% reduction of quick response well pumpage in 2002 results in 4.8 AF saved for each 1000 AF not pumped.

• 50% reduction of quick response well pumpage in 2001 results in 6.2 AF saved for each 1000 AF not pumped.

• 50% reduction of quick response well pumpage in 2002 results in 9.8 AF saved for each 1000 AF not pumped.
  

This chart shows that the allocation for the area goes up by 30,000 acre feet, if the area makes a reduction in 2003 of 10% of usage from all acres and a 25% reduction in usage by the QR wells.  The allocation increases by a small amount more, if the reduction on QR wells is 50% instead of 25%.  We can find no logical explanation for the data this chart is based on.  The lines show the use as measured by the Model for various plans.  This chart shows the most logical choice would the blue line and the purple area.  The 10% reduction in all and the 25% of QR.  This data is strange enough we think it has errors in it.  However, it is next to impossible to get those that generate the data to respond to any questions.  And why should they whent he policy makers don't care?