Nebraskas Integrated Management Plans Ensuring Compact Compliance

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Nebraskas Integrated Management Plans Ensuring
Compact Compliance
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Overview

• RRCA Compact Accounting
• RRCA Compliance Tests
• Nebraskas Integrated Management Plans (IMPs)
• Dry year considerations
• Timeline for modification of IMPs

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RRCA Compact Accounting

• The RRCA computes the water supply that was
  available for beneficial use for each year.
• This accounting is always done after the fact.
• Each states allocation is based on this computed
  water supply.
• Nebraska also receives an Imported Water Supply
  Credit.

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RRCA Compact Accounting

• The Computed Water Supply consists of
• The gaged streamflow,
• Surface water diversions,
• Stream depletions due to groundwater pumping,
• Reservoir evaporation.
• The diversions, groundwater depletions, and
  evaporation are all lumped together as each
  states Computed Beneficial Consumptive Use (CBCU)

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Republican River Compact Sub-basins
Map here.
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RRCA Compliance Tests

• Each year, Nebraskas allocation plus Imported
  Water Supply Credit is compared to its CBCU to
  determine the balance for that year.
• Allocation CBCU IWS Balance

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RRCA Compact Compliance

• Normal Year Administration (NYA)
• Always done.
• Uses the allocation and CBCU for the entire basin
  above Hardy.
• Uses a 5-year average of the annual balances.
• The NYA test for 2009 would be the average of the
  annual balances from 2005-2009

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RRCA Compact Compliance

• Water Short Year Administration (WSYA)
• Only done in Water Short Years (when irrigation
  supply in Harlan County Lake is less than 119
  kAF).
• Uses the allocation and CBCU for the portion of
  the basin above Guide Rock.
• Uses a 2-year average of the annual balance above
  Guide Rock
• If 2009 had been Water Short, would take the
  average of the annual balance from 2008-2009.

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RRCA Compact Compliance

• Alternative WSYA
• The Settlement allows for Nebraska to ask the
  RRCA for Alternative WSYA.
• If approved by the RRCA, this allows Nebraska to
  use a 3-year average instead of a 2-year average.
• Not always beneficial, need to determine if it
  improves the average if we go back and grab the
  extra year.

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History of RRCA Accounting for 1995-2008
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History of RRCA Accounting for 1995-2008
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History of RRCA Accounting for 1995-2008
2008 values are preliminary and subject to
change.
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RRCA Compact Compliance

• The Computed Water Supply goes up and down with
  wet and dry cycles (changes in gaged streamflow).
• Groundwater depletions change very slowly.
• Changes in CBCU from surface water diversions
  depends on whether the source is natural flow or
  storage.
• During a dry period that might go up at first
  then drop as storage water runs out.

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Nebraskas IMPs

• Have two requirements
• Overall pumping is capped at 80 of the volume
  pumped during the baseline period (1998-2002)
• Groundwater depletions must not exceed the
  allowable groundwater depletions.
• Allowable Groundwater Depletions The maximum
  level of groundwater depletions that will result
  in Nebraska being in compliance with the Compact.

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Nebraskas IMPs

• Pumping limitations are designed to keep Nebraska
  in compliance during average and wet years with
  no further action required.
• During dry years, additional actions may be
  required to maintain compliance with the IMPs and
  the Compact.
• Dry-year leasing
• Augmentation
• Regulation

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Water Supply vs. CBCU
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Compliance Tests
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Kansas Remedy
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Dry year considerations

• Issues that need to be addressed
• Compact accounting is after the fact
• Water short year determination is made half way
  through year two of the two year averaging
• Very good years can drop off and change the
  5-year average very quickly
• Surface water supplies and/or augmentation
  deliveries may not be available when they are
  needed

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Dry year considerations

• These can be overcome by
• Developing a forward-looking monitoring system
• Developing triggers to ensure that Nebraska is
  maintaining enough of a cushion to withstand a
  dry year
• Working to put the needed surface water contracts
  and augmentation systems in place, along with the
  needed funding mechanisms.
• Implementing the necessary regulations when
  needed, but only as a measure of last resort.

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Timeline
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Questions?