HomeMy Public PortalAboutMinutes_CCWorkMeeting_02212012CITY COUNCIL WORK MEETING FEBRUARY 21, 2012 6:00 P.M. IONA COMMUNITY
CENTER
PRESENT: Mayor Brad Andersen, Council President Bruce Case, Council member Dan Gubler,
Council member Rob Geray, Public Works Supervisor Zech Prouse, City Clerk Robyn Keyes,
Treasurer, Deputy Clerk Amy Sullivan, Police Chief Shannon Basaraba.
Visitors: Thane Price, Bryce Contor, Jason Helms, Del Kohtz.
Rocky Mountain Environmental Associates (RMEA)
Bryce Contor from RMEA handed out information regarding possibilities for increasing the
City's water rights. Contor said the City had an adequate supply of water for culinary use, but
was deficit for irrigation purposes. Mr. Contor suggested the City keep the water rights with any
future annexations.
Del Kohtz from Idaho Water Company said he had water rights available for sale that were
$1,000 per acre foot.
Mr. Contor said the rights Mr. Kohtz had available would be enough to add another well for
redundancy and emergency purposes such as fire protection. Mr. Contor also said the City can
receive money for any water not used during the year from the water rights.
Mayor Andersen said he learned during the Iona Capitol for the Day event that the City could re-
apply for the 2007 well permit that the City already had submitted.
Mr. Contor agreed that by implementing a mitigation plan it would resurrect the application the
City had submitted in the past.
Council member Gubler asked what had happened to the water rights from the annexations of the
subdivisions within the City.
Public Works Director Prouse said the City retained the rights from Country Haven, but the
irrigation district reclaimed the rights from the developments after Country Haven.
Mayor Andersen said the City attorney suggested that the assessment fees from the rights would
be an unnecessary burden since the City could not use the water at the time, so the City yielded
the water rights.
Council member Gubler asked if the city could get the rights back.
Mr. Helms said other Cities were unsuccessful through court to regain the water rights for
properties within their jurisdiction.
Mayor Andersen said many changes have been taking place in the Legislation regarding water
rights. The Mayor said some of the other cities within the district were considering pooling their
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money to help support lobby efforts regarding local water rights and suggested the City of Iona
join with those efforts.
The Mayor thanked Mr. Contor, Mr. Kohtz, and Mr. Helms for their time and said the Council
would need time to consider the issues.
Reports
Chief Basaraba reported that he had been selected by the Idaho Transportation Department
(ITD) to attend a highway safety conference in Orlando Florida. ITD will pay all expenses for
Basaraba to attend the five day conference from July 13 to July 17. The Chief said he would like
to stay four more days and make the trip a family vacation as well.
Mayor Andersen said the reason he wanted to discuss the training was because the Chief would
also be gone for three weeks in August for training in Chicago. The mayor said he wanted to
make sure there would be law enforcement coverage for the City while the Chief was gone.
Council member Geray asked what the ITD training topic was. Chief Basaraba said it was about
traffic safety and decreasing fatalities.
Mayor Andersen suggested the Council take another look at the water study conducted for the
City and think about planning for future water needs, the costs involved, and the payment
options.
Director Prouse reported he was waiting for more information regarding the street light
proposal from Rocky Mountain Power. The proposal included the City purchasing all of the
street lights within the City limits and becoming responsible for their maintenance in exchange
for a lower rate fee for power. Prouse said an assessment must be conducted first. Prouse said the
City could save approximately $3,600 a year on rate fees but a contractor to maintain the street
lights would cost approximately $4,800 a year. One benefit to owning and maintaining the street
lights would be faster service for maintenance.
Council member Geray and Thane Price liked the idea of faster service for repairs and
maintenance.
Chief Basaraba said he saw advertised a water filtration system that could purify ditch water into
potable water and suggested the Council purchase some for emergency purposes.
The Mayor said the filters could be placed at different points throughout the city for relief
purposes.
Meeting adjourned 6:57 pm.
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daho Department of Water Resources
http://www.idwr.idaho.gov/WaterInformation/Projects/esparr
• Water Data
• 4- Hydrologic Projects
Eastern Snake Plain Aquifer Model
The Eastern Snake Plain Aquifer at Thousand Springs, photo by U.S.
Geological Survey
Introduction
The Eastern Snake Hydrologic Modeling Committee (ESHMC) is
composed of hydrologists and modelers from state and federal agencies,
private industry and the University of Idaho. The group was formed in
1998 with the following mission:
Evaluate the status of hydrologic modeling on the Eastern Snake River
Plain and tributary basins, define objectives for modeling efforts, assess
data and technical needs, and provide technical support and peer review
for the modeling process.
Objectives
1. Establish a coordinated, inter -agency approach to improve the
ground water flow modeling system of the Snake River Plain to
address the demands of current and emerging water resource issues
within a reasonable cost and timeframe. The coordination will pull
together what may otherwise be piecemeal efforts of agencies into
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Related Links:
Eastern Snake
Hydrologic
Modeling
Committee
• ESHMC Meetings
• ESHMC White
Paper (KB)
• ESHMC Updated
White Paper
Eastern Snake
Plan Aquifer
• ESPAM (All Data)
• ESPA CAMP
• ESPAM 2 Design
Docs
• ESPAM 2 Final
Report
• ESPAM 3
• ESPA Monitoring
Data
• ESPA Model
Articles
• ESPA Model
Boundary
• ESPA Model Files
• ESPA Model Tools
• ESPA Model Trim
Line
• ESPA Model
Uncertainty
• On -Farm Water
Budget
• ESPAM 2
Recharge Tool
1/26/2012 7:30 PM
daho Department of Water Resources
http://www.idwr.idaho.gov/WaterInformation/Projects/espan
PIN
of 3
an organized and comprehensive program.
2. Enhance and refine the existing model to better represent the
physical system, with an emphasis on the interactions of surface
water and ground water.
3. Develop a framework (process/procedure) to quantify estimates of
uncertainty in model parameters and predictions.
4. Establish a framework within which modeling work is implemented,
coordinated and reviewed among experts in state and federal
agencies and universities.
Eastern Snake Hydrologic Modeling Committee Members
Organization
Idaho Department of Water Resources
US Fish and Wildlife Service
Idaho Water Resources Research Institute
Hydrosphere Resource Consultants
Brockway Engineering, PLLC
US Fish and Wildlife Service
Idaho Power Company
University of Idaho, Graduate Research A
US Fish and Wildlife Service
Principal, Leonard Rice Engineers, Inc.
Idaho Water Resources Research Institute
US Geological Survey
Idaho Water Resources Research Institute
Spronk Water Engineering, Inc
Leonard Rice Engineers, Inc.
Idaho Water Engineering
May, Sudweeks & Browning, LLP
HyQual
Idaho Power Company
Idaho National Laboratory
US Bureau of Reclamation
US Geological Survey
Leonard Rice Engineers
HDR, Inc
Public
Idaho Power Company
US Geological Survey
(Idaho Falls)
sst.
(Idaho Falls)
(Idaho Falls)
• ESPA Scenarios
• Idaho Water
Resources
Research Institute
(IWRRI) - Eastern
Snake Plain
Reports and Design
Documents
• Water Resources
Research at the
Kimberly Research
and Extension
Center
1/26/2012 7:30 PM
daho Department of Water Resources http://www.idwr.idaho.gov/WaterInformation/Projects/esparr
. s
Idaho Aquaculture Association and Thousand Springs Water Users
Association
Idaho Department of Water Resources
US Bureau of Reclamation
Idaho Department of Water Resources
University of Idaho - Kimberly Research Station
Idaho Department of Water Resources
Rocky Mountain Environmental
Idaho Department of Water Resources
US Bureau of Reclamation
Idaho Water Resources Research Institute (Idaho Falls)
Idaho Department of Water Resources
Idaho National Laboratory
Principia Mathmatica
Huntsman Corporation
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1/26/2012 7:30 PM
005
ock, WowItairt
EWR NTAI:
ASSOCIATES, INC.
MEMORANDUM
To: Eastern Idaho Water Rights Coalition
Fr: Bryce Contor
Date: 21 December 2011
Re: Report on 12 December Eastern Snake Hydrologic Modeling Committee
On December 12, 2011, Bryce A. Contor of Rocky Mountain Environmental Associates,
Inc. (RMEA) attended the Eastern Snake Hydrologic Modeling Committee (ESHMC)
meeting in behalf of and in representation of the Eastern Idaho Water Rights Coalition
(Coalition). This is a committee of technical representatives assembled to give IDWR
non -binding advice on hydrologic modeling in general, and on the Eastern Snake Plain
Aquifer Model in general. There are two versions of the model; ESPAMI.1 was
developed from 2001 through 2004 and is currently used by IDWR for planning and
administrative purposes. ESPAM2.0 has been under development since 2005 and is
nearing completion.
This memorandum reports on individual discussion items and their implications for
eastern Idaho water interests.
I have inserted comments into the agenda provided by IDWR. Underlined type is used
for IDWR agenda headings, normal type is used for my brief summaries of discussion
and italic type is used to highlight important implications for the Coalition.
1) Introductions
The meeting was well attended, with most water -user interests represented.
The only agency represented was Idaho Department of Water Resources.
2) Committee business
a) Data gathering for model validation effort [Stacey Taylorl
The plan for model deployment has included three steps: 1) Complete
calibration; 2) Validate the model; 3) Assess the model, including assessment
of uncertainty.
482 Constitution, Idaho Falls, Idaho 83402-3537 • (208) 524-2353 •
FAX (208) 524-1795 • www.rockymountainenvironmental.com
The model is being calibrated using a data set from May 1980 through October
2008. In previous ESHMC meetings it has been agreed that validation will be
performed by applying the calibrated model to data for November 2008
through October 2010, to see if it reasonably reproduces observed aquifer
water levels and spring discharges after the end of the calibration period.
Taylor of Idaho Water Resources Research Institute (IWRRI) has been tasked
with gathering the 2008 - 2010 data. She reported that all major data are in
hand, with final processing expected to be complete by January 2011. Some
minor data elements will likely need to be estimated.
The validation will provide useful information to the Coalition regarding the
potential accuracy and usefulness of the model.
b) other
Only procedural and scheduling issues were discussed.
3) Western ESPA METRIC data vs. ESPAM calibration data for 2000, 2002, 2006,
and 2008 [Michael McVay]
An important part of calibration is to compare model output with various
known, measured data. These measured data are referred to as "targets" and
the goodness of the comparison is referred to as "fit" or "match."
In the current state of the model, the fit of spring targets show a marked
divergence between observed and modeled values in the final two or three
years of the calibration period. This is especially pronounced at high -elevation
target springs such as the springs that feed the Rangen facility near Curren
Tunnel.
One hypothesis put forth to explain this phenomenon was that perhaps there
was an increase in evapotranspiration in the last few years of the calibration
period, which was not captured by the model data. Michael McVay of IDWR
reported on work he had done to test this hypothesis by comparing model
evapotranspiration data with remote -sensing evapotranspiration estimates
calculated using the METRIC method. His results were inconclusive but pointed
out some of the difficulties with the methods used in the model data, as well as
the confounding effects of differences in irrigated -lands data.
McVay's report underscores some of the limitations of the model input data. It
Rocky Mountain Environmental Associates 2
watchful that such efforts are fully reviewed and vetted by the ESHMC, as occurred
in this case.
7) Lunch on your own
8) Ground water underflow between Kimberly and King Hill [Allan Wyliel
a) Description and evidence of underflow
b) Current model allocation of underflow to Group C calibration targets
c) USGS gage data — river gains
d) Re -allocation of underflow
Allan Wylie is the chief calibrator of the model and an IDWR employee.
His discussion related to the locations where the model represents that
discharge from the aquifer to the springs and river occurs.
The total contribution of springs to the Snake River between Kimberly and
King Hill is known with a reasonable degree of certainty, based on the
difference in gauged flows in the Snake River and reasonably good
estimates of flow contributions from the south side of the river.
The discharge of some individual springs is also known with reasonable
certainty. Past practice has been to assign these known individual
discharges to the locations where they occur, and distribute the remainder
of the total reach gain along the rest of the model cells in the Kimberly to
King Hill reach of the river.
As calibration of ESPAM2.0 has progressed, more and more data have
been obtained for individual springs. This has forced the unaccounted
flow into fewer and fewer model cells. Wylie reported that the remaining
cells are few enough that this representation results in more water being
applied to those cells than is reasonable. His presentation was on a
conceptual explanation of how additional water may be reaching the
Snake River in all model cells in the reach, including those with discrete
spring targets. Wylie proposed a method to represent this flow as direct
underflow into the river using a particular modeling algorithm.
After significant discussion, the committee generally accepted Wylie's
methodology and recommendations.
Because the spring reaches are in the western part of the aquifer, this
issue does not have large impact on the Coalition.
Rocky Mountain Environmental Associates 4
9) Discussion of ESPAM version 2.0 predictive uncertainty [Allan Wylie]
Predictive uncertainty is a subset of overall model uncertainty. At one time the
ESHMC had agreed that predictive uncertainty should be evaluated as part of
the process of assuring that ESPAM2.0 is ready for use, and agreed upon
methodology to perform the evaluation. Interim Director Gary Spackman had
stated at an earlier meeting that he required an evaluation of predictive
uncertainty before deploying ESPAM2.0.
This part of the meeting involved significant discussion of not only predictive
uncertainty, but uncertainty in general. John Koreny (representing the Surface
Water Coalition) was the most vocal opponent of performing a predictive
uncertainty analysis, but there was strong opposition from a number of
attendees and consensus on neither whether nor how predictive uncertainty
should be evaluated.
While the ESHMC is nominally a technical advisory group, there was significant
discussion of the policy question of a "trim line." The trim line is a geographic
delineation that IDWR has applied in administration of aquifer calls.
Groundwater rights falling within the trim line are subject to a given call, while
those outside are not. The trim line for each call is constructed using the
groundwater model. The current definition is that wells are subject to
administration if they lie within a model cell where 10% or more of the
pumping would eventually affect the model reach where the call was made. In
the past, IDWR has defended the choice of 10% as a cutoff based on an
assertion that this is an estimate of the uncertainty of the model. Hence, it is
possible that an assessment of lower uncertainty in the model might result in a
lower threshold for the trim line, which would subject more Coalition members
to administration than does current policy.
Interim Director Spackman attended part of this discussion and clarified that he
was not so much interested that specifically a predictive analysis be performed,
as that the ESHMC provide guidance as to whether the model is appropriate for
use in administrative decisions which have significant financial impact on
participants.
The ESHMC generally agreed (in some cases, it appears with reservations) to
continue this discussion at the next ESHMC meeting in January 2012. Rick
Raymondi of IDWR (who chairs the meetings and supervises the IDWR
technical staff) followed up with an e-mail on December 15 requesting
members to "develop comments and suggestions in writing regarding the use
Rocky Mountain Environmental Associates 5
of a trim line."
This is a very important issue for the Coalition. Because of the trim line, all
Coalition members have previously been isolated from administration of aquifer
calls in the Twin Falls/Thousand Springs area. Another of these calls was filed
just recently on December 14. Some Coalition members have also been
isolated from administration of calls by the Surface Water Coalition.
In addition, the issues of uncertainty and model reliability are important in the
context of administration of water right transfer applications Current
interpretation and application of ESPAMI.1 has made many water right
transfers in eastern Idaho very difficult to accomplish without sacrificing a
significant portion of the water right, providing other mitigation, or performing
complex and costly offsetting transfers This is especially true for locations in
and around the Rigby Fan area (ie. Rigby, Rexburg, Newdale) and areas
upstream of the confluence of the Henrys Fork and South Fork of the Snake
River.
We agree that predictive uncertainty is a new concept in modeling protocol,
and understand that not all modelers accept it as part of standard protocols
We also stress the importance of considering the uncertainty of input data
themselves We feel strongly that given the potential impact of administrative
decisions on the livelihood of coalition members, any pronouncement of the
models ability to predict the depletion of water should be reasonably
coincident to the uncertainty of the model data inputs In simple terms, we
don't believe that the model can reliably predict flows in the aquifer within the
0.1 % range when the most accurate model data inputs are held to have an
uncertainty in the 10% and higher range.
RMEA intends to prepare a draft response to Raymondi s request, for approval
by Coalition leadership and presentation to IDWR.
Rocky Mountain Environmental Associates 6
EASTERN IDAHO
WATER RIGHTS COALITION
Executive Committee:
Roger Warner,
President
Scott Brace
Dr. Rebecca Casper
Administrator
Stan Clark
Past President
Craig Evans
Mayor
fared Fuhriman
Comic), Liddiard
Senator
Dean Mortimer
Nathan Olsen
Counsel
fefrRaybould
Dave Richards
Randy Skidmore
Dale Swensen
Christian Taylor
Mayor
Richard Woodland
EASTERN IDAHO WATER RIGHTS COALITION
P.O. Box SOI25 • Idaho Falls, ID • 83405-0I25
12 January 2012
Rick Raymondi
Idaho Department of Water Resources
322 Front Street
Boise, Idaho 83720-0098
Re: Eastern Idaho Water Rights Coalition input on Trim Line.
Dear Mr. Raymondi:
This letter is a response to your invitation to members of the Eastern Snake Plain
Hydrologic Modeling Committee (ESHMC) to "develop comments and
suggestions in writing regarding the use of a Trim Line" and predictive
uncertainty. It is made in behalf of the Eastern Idaho Water Rights Coalition
(EIWRC). We respond with background and general comments, discussion of
modeling issues, discussion of policy issues, and recommendations. While we
focus on Eastern Snake Plain Aquifer Model Version 2.0 (ESPAM2.0), most of the
comments apply also to Eastern Snake Plain Aquifer Model Version 1.1
(ESPAMI.1).
BACKGROUND AND GENERAL COMMENTS
EIWRC agrees with the comments of Dr. Willem Schreuder and Dr. Chuck
Brendecke that the appropriate questions to ask are broader than just the Trim
Line and predictive uncertainty. We agree with Interim Director Spackman that
the essence of the Director's need is for the ESHMC to provide input to the
Department on appropriate uses and application of ESPAM2.0; what the model
can and should do, and what it cannot and should not. We suggest that the most
important category for consideration is the realm of things which the model can
do but should not.
We agree with John Koreny that uncertainty is addressed by the entire data
gathering and modeling process, and that the ESHMC, IDWR and IWRRI have
worked very hard to address uncertainty by refining the model and model data.
We also agree with Dr. Brendecke that uncertainty can be assessed and we assert
that it should be. Most sources of uncertainty can at least be discussed
qualitatively and many can be estimated quantitatively. Predictive uncertainty can be rigorously
assessed quantitatively using published methodology.
DISCUSSION OF MODELING ISSUES
While we believe the Trim Line and a deminimus standard are primarily policy questions, some
technical modeling issues should be considered. All models are of necessity simplifications of reality.
Simplification occurs because of lack of data, lack of knowledge of subsurface geometry and geology,
lack of sufficient computing power, the need for timely completion of the modeling process, and finite
resources with which to conduct data gathering. Despite their limitations, models can be extremely
useful. Numerical groundwater flow models are often more useful than analytical solutions to
groundwater flow equations because the numerical model can better approximate complex geometry,
geology and spatial distribution of aquifer properties.
The ESPAM2.0 model is a refinement of ESPAMI.1. ESPAMI.1 was developed with participation of the
ESHMC, and development of ESPAM2.0 is proceeding with even greater ESHMC participation.
ESPAMI.1 has been deployed by IDWR in determining obligations under delivery calls for conjunctive
administration of groundwater and surface -water rights, and for evaluation of potential injury from
transfers of groundwater rights. This document discusses the applicability of ESPAM2.0 to the same
kinds of administrative decisions.
This discussion of modeling will touch on four areas: 1) Procedural uncertainty; 2) Limitations of
conceptual model; 3) Water budget data limitations; 4) Predictive uncertainty.
Procedural Uncertainty
In any process where the outcome materially affects the livelihood or financial fortunes of
stakeholders, robust procedural protections are vital. Without implying any lack of professionalism or
casting blame, EIWRC suggests that wherever there is simultaneous occurrence of opportunity and
motive to bias modeling outcomes, great caution is in order.
In development of ESPAMI.1, most technical work was performed by IWRRI under the direction of
IDWR, with some input data prepared by IDWR. The ESHMC process was used to receive non -binding
technical input and to provide full transparency of the technical process. ESHMC input was considered
but at times overridden by IDWR decisions, often at the suggestion of IWRRI. Hence, the procedural
uncertainty of ESPAMI.1 is limited to the opportunities and motives that would have existed within the
IDWR and IWRRI team.
ESPAM2.0 development differs in two important ways. First, ESHMC input has carried significantly
more weight, with much less willingness of IDWR to override ESHMC input. Second, ESHMC members
have provided much technical input to the ESPAM2.0 development process. This has occurred in three
areas:
1. Provision of input data by ESHMC members or their clients. These have primarily been refined
data on spring discharges, to be used as modeling targets.
2. Provision and review of the On -Farm algorithm and MKMOD software for calculating net recharge
associated with irrigation.
3. Participation in core modeling decisions of parameter -estimation setup, weighting of targets,
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calibration algorithms, and identification of water budget components to subject to parameter
estimation.
The procedural uncertainty of ESPAM2.0 includes not only the potential motivations and opportunities
of IDWR and IWRRI, but of all the participants in the three technical areas described above. EIWRC
strongly recommends that IDWR explicitly and deliberately evaluate whether adequate oversight,
transparency and accountability have been provided to address the issues of opportunity and motive
surrounding all technical input to the modeling process. This is not meant to be an assertion of
impropriety, but an effort to protect both the product and the participants.
Limitations of Conceptual Model
The conceptual model used in ESPAMI.1 and ESPAM2.0 differs from our actual understanding of the
physical system in at least four important ways:
1. The model is a single -layer representation. However, there is strong physical evidence of vertical
separation of aquifer zones or perhaps separate aquifers in a number of areas, including the
Henrys Fork, the Rigby Fan, and the Burley area. There are anecdotal indications of two vertical
zones in the aquifer immediately above the canyon rim west of Wendell.
2. The model represents the aquifer as a locally uniform porous medium, with aquifer properties
smoothly interpolated between a few hundred pilot points distributed across an area of
approximately 11,000 square miles. In reality we believe that much of the aquifer is hosted in
fractured basalt (itself non -uniform), and that there are locations where the aquifer abruptly
transitions between basalt and unconsolidated sediments, in either the vertical or horizontal
direction.
3. The model uses the USGS MODFLOW code, which can only represent the hydraulics of spring
discharge using the linear Darcy equation.' This may differ from reality:
3.1. Spring discharges are large enough, and confined to small enough discharge areas, that flow
velocities may be high enough to violate Darcian flow assumptions, even if occurring in a
locally uniform porous medium;
3.2. The existence of discrete springs (rather than a broad seepage front) and observation of
rubble zones and fractures on the canyon face suggest that fracture or conduit flow may
actually govern spring discharges. This type of flow is more likely to be governed by non-
linear turbulent processes.
4. The model does not explicitly represent distinct fault zones and breaks in subsurface geology
known to exist in the Rexburg Bench and Oakley Fan areas.
These departures from reality were taken deliberately and for good reasons, and in our opinion are
generally appropriate given the resources and data available for this modeling project. Nevertheless,
these conceptual model decisions have important implications on uncertainty and spatial and temporal
applicability of the model.
1. Single -layer representation means that all wells in a small geographic region will be represented to
have essentially identical effects upon springs and river reaches. In reality a deep well completed
in a lower aquifer will tend to have more of its effects expressed at distant locations, while a
nearby shallow well will have more of its effects expressed at nearby springs or river reaches.
Similarly, in reality the propagation of effect from the deeper well will be delayed in time relative
to the shallower well.
2. Representation as a locally uniform porous medium also tends to attribute similar effects to wells
in a small geographic region. In reality two nearby wells may have markedly different effects, if
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one is completed in gravels and another in adjacent basalts, or if one is near a fracture zone and
another is within a mass of relatively unbroken rock.
3. Using a linear representation of what may be non -linear hydraulic processes has directly affected
the combinations of aquifer parameters and adjustments to input data that have been adopted in
parameter estimation, in order to best match the temporal hydrographs of target discharges.
4. Omission of known faults and geologic boundaries means that modeled indication of propagation
of effects across these boundaries will most likely be incorrect.
All of these uncertainties are a function of the spatial scale at which answers are sought. If the
question is asked: "How much pumping at location X will propagate to river and spring reaches?" the
answer can be determined with very little uncertainty, and independently of the limitations described
above.
If refined estimates of above -Milner vs. below -Milner effects are required, the uncertainty depends on
the location of the well. For wells distant from Milner, none of these conceptual simplifications are
likely to materially affect the answer. For wells near to Milner, all of these affect the results and a
different set of assumptions would be expected to produce a markedly different result.
Similarly, refining the question to include some understanding of the timing of effect begins to
introduce additional uncertainty. The answer to "How much. will propagate in time period Y" is less
certain than "How much will eventually propagate," and results are sensitive to changes in conceptual
simplifications.
Water Budget Data Limitations
IDWR, IWRRI and the ESHMC have expended much effort to refine input data, and ESPAM2.0 will
include a number of improvements over ESPAMI.1. Nevertheless, there is still significant uncertainty
associated with input data. Water budget data uncertainty derives from imprecise knowledge of the
quantity, location and timing of fluxes of water. These propagate into uncertainty in the ability of the
model to correctly predict the quantity, timing and location of effects from pumping, recharge or
mitigation efforts. While a given percentage of uncertainty in a water -budget component does not
translate directly to the same numerical uncertainty in model results, concepts of uncertainty should
still inform deliberations of demiminus policy.
Quantity Uncertainty. In a modeling scenario," IWRRI calculated the standard deviation of the
ESPAMI.1 aquifer water budget at approximately 440,000 acre feet per year. This translates to an
expected range of uncertainty"' of plus or minus 880,000 acre feet, or about 17% of total annual flow
through the aquifer. However, the estimated uncertainty of individual water budget components
ranged as high as plus or minus 50 percent.
Spatial Uncertainty. The model uses one -mile grid cells, but this does not mean the spatial resolution
of data is at a scale of one mile.
1. The location of individual irrigated parcels is derived from remote sensing data, with a precision of
approximately 30 to 400 meters (including issues of georeferencing), depending on the data set.
2. Precipitation data are based on only a handful of weather stations distributed across 11,000 square
miles, but are interpolated to a four -kilometer grid.
3. Recharge from precipitation on non -irrigated lands is derived from precipitation data and from
generalized soils maps with a horizontal precision of perhaps one kilometer.
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4. An important consideration of spatial uncertainty is the fact that evapotranspiration of irrigated
crops is represented by a single crop mix and single reference evapotranspiration depth, per
county.
5. Surface water diversion volumes are applied to entire groups of canal companies or irrigation
districts, without data to inform more refined distribution.
6. Spatial distribution and total quantity of application of surface water to mixed -source lands is
poorly understood.
Temporal Uncertainty. Diversion data from Water District 01 are available on a monthly basis.
Diversion data for some non -Snake sources were obtained only on an annual basis, and were
interpolated to monthly values. Estimates of tributary underflow volume were obtained on a long-
term average basis and were interpolated to monthly values.
Effects of Water Budget Uncertainty. The model calibration process consists of adjusting model aquifer
properties, and in the case of ESPAM2.0, water -budget inputs, to aid the model's ability to match
observed targets. Imprecision in the water budget will affect the calculated model aquifer properties,
which in turn affect the model's prediction of effects of pumping, recharge or mitigation.
Quantity imprecision in the water budget is likely to mostly affect the overall range of transmissivity
and storage coefficient, and river and spring conductance values. This will have some effect on the
model's ability to spatially distribute effects, and more effect upon its indications of timing of effects.
Spatial imprecision interacts with the conceptual model consideration of a locally uniform porous
medium, spring hydraulics, the one -mile model grid cells, the number of pilot points, and the effort to
calibrate to individual spring targets. While the excellent results obtained for many target springs are
admirable, we submit that given the spatial imprecision of input data, these matches were only
obtainable by false precision in the array of aquifer properties, and perhaps false precision in
modifications to water -budget data. Combining this serious consideration with conceptual model
limitations suggests to us that while the model can estimate effects at individual springs, it should not
be applied to administrative decisions on an individual -spring basis. Similarly, the model can estimate
on a cell -by -cell basis the effects of groundwater transfers, but transfer decisions should not be made
on a single -cell basis.
The effects of temporal imprecision are analogous to the effects of spatial imprecision, but are
compounded with concerns about the difficulty the calibrators have had in matching seasonal
amplitude in some target springs. These suggest to us that while the model can be used to estimate
effects on a monthly basis, it should not be used to make administrative decisions that hinge on
monthly distribution of effects.
POLICY DISCUSSION
The concept of a Trim Line is essentially an identification of a deminimus standard below which
groundwater rights will not be administered to satisfy a conjunctive administration delivery call. We
believe it is similar in concept and nature to the concepts currently applied to groundwater -right
transfer analysis, in both the minimum transfer distance which triggers analysis and in the minimum
percentage change in modeled effect that requires mitigation. Both hinge upon the spatial and
temporal resolution at which the model can be relied upon. This general policy discussion is meant to
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apply broadly to all these topics and specifically to the narrower "Trim Line" question. It is presented
as a series of questions that EIWRC suggests must be further explored. We believe that these policy
questions are weightier considerations than the modeling discussion presented above.
Questions
1. Can the Conjunctive Management Rules" paragraph 010.07 definition of Futile Call provide
guidance on a deminimus impact?
1.1. If a well is curtailed where 10% of the foregone extraction benefits the target reach, this
means that 90% of the foregone extraction does not benefit the reach. Does the criterion of
preventing "waste of the water resource" apply to this reallocation of 90% of the groundwater
pumper's water right to reaches where no relief has been ordered?
1.2. When wells are distant from the target reach the benefits of administration are delayed.
For instance, ESPAMI.1 indicates that if a well were administered at model cell Row 5 Column
106 (within the 10% Trim Line for Near Blackfoot to Milner), less than 0.1% of that reach's
benefit would accrue the irrigation season that administration occurs. This extreme case
leaves more than 99.9% of benefit to arrive after it has been determined to be needed.
Should the criteria of satisfaction "within a reasonable period of time" inform the deminimus
decision process?
2. Do Judge Wood's discussions" of providing relief "consistent with the exigencies of a growing crop
during an irrigation season" and protection of "crops in progress, being green" inform the
considerations of "reasonable period of time?"
3. Does the Idaho State Constitution"' provide guidance with its requirement that the legislature may
provide "limitations [of priority of use] as to the quantity of water used and times of use... having
due regard both to such priority of right and the necessities of those subsequent in time?"
3.1. Does legislative adoption of the Conjunctive Management Rules satisfy the requirement of
legislative provision?
3.2. While the specifics of the discussion in the constitutional convention were different from
the specifics of conjunctive administration, conjunctive administration was not yet
contemplated at the time of the convention. Does the Constitution apply to general principles
or only to specifics debated and considered by the convention?
4. The defacto assumption in transfer administration, without evaluation or analysis, is that any
change in location or timing of effects of pumping will work injury. Is this justified?
RECOMMENDATIONS
1. The ESHMC and IDWR should adopt the list of elements of uncertainty proposed by Dr. Brendecke.
All should be described qualitatively and where possible a quantitative estimate should be
provided. Those amendable to more precise quantification (such as the water budget) should be
further specified.
2. IDWR should proceed with the analysis of predictive uncertainty following guidelines published by
Dr. John Doherty, author of the PEST software used in calibration of ESPAMI.1 and ESPAM2.0,
using the outline proposed by Dr. Allan Wylie.
3. It is appropriate for the Department to consider some deminimus standard for water right
administration. While model uncertainty must be part of this evaluation, it is the smaller part.
4. The spatial scope and scale of model application to administrative questions should be constrained
by the factors presented in the model discussion above.
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4.1. For administration of water delivery calls, the model should be used on a reach basis and
not an individual cell basis.
4.2. Transfer analysis should be made on a zone basis v" Fifteen to twenty zones should be
considered.
4.3. Recharge within any of the transfer zones should be deemed applicable to mitigation
requirements within the same zone, without discount or additional analysis.
5. The model should not be applied for administrative purposes to time scales finer than quarterly
(three months).
6. The Department should consider University of Idaho work""' suggesting that transfers in aggregate
tend to be in self -canceling directions. It would be very possible to set up a robust set of rule -of -
thumb guidance principles (i.e. transfers moving in the eastward direction must mitigate by
surrendering X% of the annual diversion volume per mile of change in location of POD; transfers in
the westward direction must surrender Y%). Periodic modeling and review of the net effect of the
prior period's transfers could allow adjustment of the guidance, while allowing transfers to
proceed at low transaction cost to the applicant and low review cost to the Department.
7. No existing administrative decision, delivery call order, approved mitigation plan or approved
transfer should be changed upon adoption of a new model. To do otherwise sets the Department
up for endless review and reworking of old decisions and analyses, and deprives all parties of
certainty in administrative decisions.
8. Administrative decisions relating to the effect of groundwater transfers on the Snake River should
be considered in light of physical delivery of water and the practical effect upon delivery of surface
water rights. Any transfer whose main consequence is to shift the location of pumping effects
between the Henrys Fork and South Fork has no physical impact on the availability of water:
8.1. Any increase in effect to either reach will be accompanied by a corresponding reduction in
effect to the other, so that the net effect below the confluence is zero;
8.2. Storage water is being delivered to downstream users at all times when priority
administration would affect either reach; hence, carriage water is always available to
physically sustain all in -priority uses above the confluence.
8.3. It is possible that current surface -water accounting would respond to the effects of the
transfer in ways that result in harm. This could happen by causing a change in the priority cut
calculated at either reach, even though adequate carriage water is present to allow physical
delivery without harm. In this case we recommend that the appropriate response is not to
deny the transfer but to update the accounting methodology.
9. We suggest that neither are technical staff the best people to provide policy input nor is the
ESHMC the best forum. We encourage the Department to consider convening a policy advisory
committee to provide non -binding policy input, so that the ESHMC can return to its original role of
providing non -binding technical input. Ideally, stakeholders themselves and not representatives
should be the members and attendees of such a group.
SUMMARY AND CONCLUSION
Eastern Idaho Water Rights Coalition appreciates the opportunity to provide input on the Trim Line,
and on the use of the ESPAMI.1 and 2.0 models. We support the use of a deminimus standard in
administrative decisions and applaud the Department's willingness to consider it.
Model uncertainty is one of many factors that must be weighed in this decision. We support
evaluation of predictive uncertainty using the plan previously authorized by the ESHMC. We also
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encourage evaluation of other sources of model uncertainty, acknowledging that in some cases the
analysis can only be qualitative.
We urge the Department to be judicious in relying on model results, especially where very fine spatial
or temporal resolutions are involved. We strongly recommend that the model not be used for
administrative decisions to either single -grid cell or single -month resolution, even though it can be
applied at these scales.
Respectfully Submitted,
Roger W. Warner,
President
Eastern Idaho Water Rights Coalition
In ESPAM2.0 the innovation of two drains per model cell has been employed. This could have allowed introduction of a
piecewise linear approximation of non -linear discharge, if the upper spring had been set at an elevation where it could dry and
re -wet as water levels fluctuate through a normal range.
Donna M. Cosgrove and Bryce A. Contor, Nathan Rinehart and Gary Johnson. 2005 Snake River Plain Aquifer Model Scenario
Update: Hydrologic Effects of Continued 1980-2002 Water Supply and Use Conditions Using Snake River Plain Aquifer Model
Version 1.1 "Base Case Scenario." http://www.if.uidaho.edu/lohnson/ifiwrri/proiects.html#model
m R. Lyman Ott. An Introduction to Statistical Methods and Data Analysis, Fourth Edition. 1993. page 90.
" Idaho Administrative Code, Department of Water Resources. IDAPA 37.03.11— Conjunctive Management of Surface and
Ground Water Resources.
In the Fifth District Court of Idaho, Case No. CV-2005-0000600, Order on Plaintiffs' Motion for Summary Judgment, July 2006.
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"' Article XV Section 5
"" Donna M. Cosgrove and Gary S. Johnson, 2005. Aquifer Management Zones Based on Simulated Surface -Water Response
Functions, Journal of Water Resources Planning and Management, ASCE. March/April 2005 pp. 89-100.
"' Gary S. Johnson, Bryce A. Contor and Donna M. Cosgrove, 2008. Efficient and Practical Approaches to Ground -water Right
Transfers Under the Prior Appropriation Doctrine and the Snake River Example, Journal of the American Water Resources
Association Vol. 44 No. 1 February 2008, pp. 27-36
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