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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 1 eRN 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. 2 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 of 3 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 of 3 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, 2 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 3 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. 4 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 5 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. 6 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 7 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. 8 "' 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 9