The Legislature’s various pronouncements about aquifer recharge do not address private aquifer storage and recovery (“ASR”) projects, except to the extent that they do confirm that aquifer recharge is a beneficial use of water.
Unlike the PBARs discussed above, which require some special treatment under the prior appropriation doctrine, ASR projects conceptually are very familiar—they simply are ordinary storage projects that have been moved underground.
Consequently, no special legislative authorization is required, and, indeed, the Legislature has as yet said nothing on the subject. More importantly, the unique legislative restrictions applicable to PBAR projects are inapplicable to ASR
593 A mass measurement of ground water levels in wells throughout the ESPA was conducted by the U.S. Geological Survey in 1980. When ESPA ground water levels were again measured in 2000, the Department of Water Resources found that over the ensuing twenty-years changes in water levels in most areas of the aquifer were insignificant, including many areas with substantial ground water development.
594 At first blush, agreements, or amendments to agreements, to allow use of federal facilities to divert or carry water for aquifer recharge or to obtain needed rights-of-way on federal lands would appear to be straightforward tasks. However, as “federal actions” they would be subject to the environmental impact review required by NEPA. And, given the potential impacts on federally listed endangered species in the Columbia River Basin, and the existence of pending federal and tribal water right claims in the Snake River Basin, extensive consultation with the National Marine Fisheries Service and U.S. Fish and Wildlife Service under Section 7 of the Endangered Species Act and consultation and/or negotiation with the Tribes almost certainly would be required.
projects. What this means is that an entity seeking to undertake an ASR project should be able to obtain a water right (through appropriation or transfer) allowing the entity to divert water from some source (surface water, ground water or storage) and place the water into the aquifer without regard to the non-subordination provisions applicable to PBAR projects.
(2) Water diversions and ASR
What about the other end? Is a separate water right required to take the water out again?
In the limited ASR matters that have come before the Department it has required the project proponent to obtain a water right permit to recover water intentionally stored in an aquifer.595
Arguably, there is no legal requirement for obtaining a new water right to recover ground water once it has been lawfully placed into storage.596 Once water has been diverted in priority and placed into aquifer storage, it should be available for withdrawal from the aquifer by the project sponsor without regard to priority. This seems consistent with the analogy to diversion from a surface reservoir. So long as the water remains under the appropriator’s “control,” the water is no longer public water, but rather has become private property. Provided that the water has been properly diverted, in priority, into storage in the first instance, and the water can thereafter be accounted for using an approved ground water model or other means, one could argue that the ASR proponent remains in constructive “control” of the water, in the same manner as the owner of an on-stream reservoir. Wells into which water can be injected can be constructed and used pursuant to rules implementing the statutes pertaining to Waste Disposal and Injection Wells, Idaho Code §§ 42-3901 through 42-3919; IDAPA 37.03.03.
The Department also attaches a priority date to aquifer storage recovery permits. This too seems antithetical to the entire purpose of an ASR project—to divert water to storage when it is available and draw upon it later without regard to priority when it is needed. The Department has obtained the same effect–in a roundabout way–through the inclusion of a condition in the water right approval that allows “out of priority” diversions of ground water to the extent that they are mitigated by ground water recharge activities. To the authors, this is a needless complication.
There is no magic in ASR projects. Like any reservoir, an ASR project typically does not create new water in the hydrologic system.597 The issue is primarily one of timing—making water available when needed. In some cases, ASR projects may be employed because they improve the quality of water. In others, the project goal may simply be to make the water physically available in a different place. Except in the limited example of diversion of water from a foreign source into a closed ground water basin, no ASR project, increases the overall quantity of water in the system.
As with any reservoir, there must be a mechanism for determining what water within the reservoir belongs to the storage right older. In the case of a surface reservoir, that calculation is relatively simple. In the case of an underground reservoir, the technical computations may be more complex. The question of control over the water, and where it goes after it is injected into the subsurface, are matters of hydraulics and hydrogeology that need to be answered by an expert, preferably one who is using reliable monitoring wells and other data. In addition, proper well construction is essential.
How much of the injected water will be available for recovery will depend on such analyses. Because water in aquifers
595 See discussion of Micron Technologies ASR project below.
596 Typically, once water has been diverted into storage, it is for all practical purposes the appropriator’s property, and may be diverted from storage as the appropriator deems necessary, provided the amounts diverted are reasonable and can be beneficially used. See Washington Cnty Irrigation Dist. v. Talboy, supra (although water diverted to storage no longer is public water, reservoir owner may not waste it); City & Cnty of Denver v. N. Colo. Water Conservancy Dist., 276 P.2d 992 (1954) (the “Blue River” case) (all water impounded must be put there only temporarily; otherwise its capture from the stream defeats beneficial use). For example, in Idaho, a storage right for a surface reservoir will note the priority of the right to divert water into storage (i.e., to capture water behind the dam), and also will identify the ultimate use(s) for which water may be released from the reservoir. However, reservoir releases of captured water are not subject to any priority constraint.
597 The “hydrologic system” here being the interconnected surface and ground water source.
moves according to geology and hydraulic head, there also will be questions of timing: will the water placed in storage still be present when the appropriator seeks to withdraw it? Thus, ASR projects raise questions not faced by surface storage owners, whose reservoirs are understood to fully capture and hold the water placed there, less seepage and evaporation (both of which generally can be calculated more accurately than movement of water underground).598
(3) Examples of ASR projects
The authors currently are aware of three ongoing projects that can be considered ASR projects: South West Irrigation District’s program on the Oakley Fan aquifer; a small pilot program being carried out by United Water Idaho in Boise, and a program—also still in the pilot stage—being implemented by Micron Technology in the Southeast Boise Ground Water Management Area.
Southwest Irrigation District (“SWID”), which is served primarily by ground water in Cassia and eastern Twin Falls Counties south of Burley, Idaho, has applications pending for the use of several injection wells in an aquifer storage and recovery (or mitigation) project. The applications have been filed in connection with SWID’s proposed mitigation plan it filed with IDWR in late 2009 in response to delivery calls affecting the Eastern Snake Plain Aquifer.
For a number of years, SWID has used surface water to recharge the aquifer underlying its members’ lands, using a variety of infiltration and injection methods. These methods have included injection of surface water into the aquifer through some 13 wells installed beginning in 1991.599 SWID annually has recharged approximately 3,900 acre-feet of surface water through these injection wells, using diversions from Cottonwood Creek, Dry Creek, and Murtaugh Lake. It also maintains a constructed infiltration ditch about 8 miles in length.600
SWID’s program is probably better described as a mitigation project, not an ASR program. As indicated above, SWID recently proposed a mitigation plan that further explains the program.601
In the Micron ASR project, the Department has required a permit to remove the water from the aquifer once it has been stored. The permit issued includes a 2001 priority date, and states that the permit is “subject to all prior water rights.” Nevertheless, conditions of approval allow out-of-priority diversions to the extent that 1) the diversions are mitigated by ground water recharge activities and 2) the diversions do not injure senior rights through direct well
interference. The Micron permit allows one hundred percent of the water injected into the aquifer to be diverted under the permit provided the diversion is in the same calendar year. To the extent water injected in any given year is not diverted in the same calendar year, recharge credits may be carried forward to subsequent years, subject to a ten percent reduction per year.602 This system of accounting for recharge credits is based upon computer modeling of aquifer hydrology prepared by Micron’s consultant and approved by the Department. It is logical that such accounting would be accomplished on a case-by-case basis.
Micron annually injects approximately 1,200 acre-feet of Boise River water into the Boise Fan Aquifer, where the Company’s production wells are located. Before being injected, the river water is put through a sophisticated membrane
598 The practitioner may wish to consult published papers or other literature in this field before implementing an ASR project. Two sources are: R. Pyne, Groundwater Recharge and Wells, A Guide to Aquifer Storage Recovery, Lewis Publishers (1995); and J.H. Peters, et al., eds., Artificial Recharge of Groundwater, A.A. Balkema Publishers (1998).
599 B. Higgs, Groundwater Management Plan of Southwest Irrigation District (Draft) at 5 and 19 (September 2001). The plan using these 13 wells is now being replaced by a larger plan involving 25 injection wells, all of which are awaiting permitting by IDWR.
Permitting requires water quality monitoring of the injected water.
600 Personal communication with Brian Higgs (October 22, 2009).
601 Other entities on the ESPA in the past have injected water through wells. An example is A&B Irrigation District, which for many years injected wastewater from its project back into the aquifer through wells.
602 Idaho Dep’t of Water Resources, Permit to Appropriate Water No. 63-31183 (February 14, 2002).
water treatment facility capable of treating some 2 million gallons per day. The injected water exceeds (i.e., is cleaner than required by) drinking water standards. In addition to water quantity, water quality and temperature are important considerations. For example, Micron’s ASR project employs river water to cool the warmer aquifer water to the temperature needed for the Company’s manufacturing processes.
United Water Idaho is the municipal water provider for the City of Boise and surrounding areas. During the winter low-demand season, United Water is injecting drinking water pumped from elsewhere in its system into nine of its production wells and recovering it in the same year over several weeks during the period of peak municipal water demand in the summer. The purpose is not to enlarge production per se, but to improve the water quality available to each of these wells. So far it has proven successful.603
Moreover, improving an aquifer’s quality also usually increases its usefulness. Thus, an ASR project focused on the quality question can effectively augment supplies because it makes productive those wells that otherwise might be off-limits.
The Department issued United Water an injection well permit for each of the injection points, but did not require new diversion permits, presumably because there is no out-of-source water being brought to the system. The water being injected has been diverted originally pursuant to one or more of United Water’s existing municipal water rights in the area and it is recovered pursuant to the water right associated with the injection well. The injection well was drilled originally in connection with the development of a municipal water right held by United Water. Hence, no new permit was required.
Because the injected water is of drinking water quality, the project carries no additional treatment requirement.604 (4) Aquifer mitigation
“Aquifer mitigation” is used here to refer to a situation that arguably is the opposite side of the ASR coin. In this scenario a project sponsor adds a particular amount of water to an aquifer (or retires a particular amount of pumping) not for the public betterment, but rather to allow the sponsor to appropriate specified amounts of ground water right that otherwise would not be in priority. The project mitigates the junior right holder’s depletion and maintains the status quo for senior pumpers using the aquifer or for tributary surface water rights. An example from Colorado is the project managed by Groundwater Appropriators of the South Platte (“GASP”), where pumpers divert flood flows and non-irrigation season from the river into leaky ditches and infiltration basins, carefully account for the amounts recharged, account for the timing of return flows of the recharged water to the South Platte River and then are entitled to pump their junior tributary wells according to a schedule that recognizes the mitigation to senior surface water rights provided by the recharge.
IDWR’s Conjunctive Management Rules specifically list recharge as an appropriate mitigation device available to any appropriator facing water right administration. IDAPA 37.03.11.43.3.d.
In Idaho, the authors are aware of several mitigation proposals involving aquifer recharge that have allowed the Department to process applications to appropriate ground water despite the Department’s current moratorium on processing new applications in the Boise Basin.605
603 Personal Communication with Roger Dittus, United Water Idaho (October 12, 2009). The constituents subject to maximum contaminant levels (mcls) in the Boise area typically are arsenic, manganese, uranium, and ammonia. In addition, some wells are affected by dissolved solids, such as calcium carbonate, which cause problems with equipment.
604 The requirement that water injected be of drinking water quality and subject to a permit can be essential in these cases.
Recently, the Idaho Federal District Court found criminal liability where a feedlot operator injected surface water into the Eastern Snake Plain Aquifer without permits. United States v. King, Case No. CR-08-002-E-BLW (D. Idaho 2009).
605 The Department has imposed an administrative hold on processing applications for new consumptive uses of water in the Boise Basin. One of the conditions under which a new application may be processed is if the applicant proposes mitigation to prevent injury to senior water rights.
In one instance, the Department has approved a relatively small appropriation of ground water from the shallow aquifer for irrigation use where the applicant proposed to divert an existing surface water right into infiltration basins near the well. The applicant provided measurements of the rate of infiltration to the aquifer from the basins and was authorized to divert the same volume from a well.606
The Department also has processed applications involving the appropriation of ground water exposed by the construction of ponds that intercept shallow ground water. The ponds are to be constructed for aesthetic purposes in residential and commercial subdivisions and no ground water was proposed to be diverted from the ponds. To account for the evaporative losses from the ponds, however, the applicants proposed to change the nature of use of natural flow water rights represented by their shares of stock in mutual irrigation ditch companies from irrigation to ground water recharge.
Each share represented the right to receive up to 0.02 cfs of water per appurtenant acre within the development. One
“share” was offered as mitigation for each acre of pond and an equivalent area of “dry up” (i.e., no future irrigation) was proposed to insure no net increase in consumptive use of water following the pond construction and transfer.607 The transferred water rights were proposed to be diverted directly into one or more of the ponds as recharge to offset evaporative losses.
Typically, “mitigation” has meant the avoidance or offset of injury to senior water rights.608 But in the above cases, there was no indication that pumping the small well or evaporation from the ponds would interfere with water levels in neighboring wells. Nor was there any indication that they actually would cause injury to senior surface water rights, although that assumption is the basis for the Department’s processing moratorium. Nor was the recharge proposed to benefit a specified senior water right or to avoid a delivery call. Rather, it was to have no net effect on the water system and water users in that system as a whole—much like the PBAR projects discussed previously. In its most simple terms, the mitigation was offered because it was a prerequisite to being able to have the permit application processed.
(5) Injection of spent geothermal water
Both to conserve the volume of a geothermal aquifer and maintain its heat energy, several holders of geothermal water rights inject the water from which varying amounts of heat has been extracted. The City of Boise’s geothermal
606 The conditions imposed on the new right concerning recharge were as follows:
The right holder shall mitigate the groundwater diversion authorized under this right by directing water diverted from the Boise River under existing water rights into unlined ponds and causing it to seep into the ground. The volume of water directed into the ponds for mitigation purposes shall equal or exceed the volume of groundwater diverted under this right each year. The ponds shall be modified and/or constructed and the seepage shall be quantified in accordance with the plan proposed [by the applicant’s consultant]. If the proposed mitigation proves to be inadequate or cannot be maintained, the Director retains jurisdiction to require modifications to maintain sufficient recharge in order to offset diversion from the aquifer under this right. The Director retains jurisdiction to require measurement and reporting of the amount of surface water supplied to the ponds for mitigation purposes.
State of Idaho Dep’t of Water Resources, Water Right No. 63-12092 (issued November 18, 1999).
607 The assumption here is that the annual evaporative loss (consumptive use) of ground water per exposed surface acre is equivalent to the annual consumptive use attributable to the same acre due to irrigation. Hence the dry up of an acre of historical irrigation offsets the depletive effect of exposing one surface acre of ground water. Depending on the consumptive use values appropriate for evaporation and irrigation in the location where the mitigation is being proposed, the applicant could be required to provide more or less mitigation water.
608 The Department’s draft Water Management Rules define “mitigation” as “[t]he result of an action taken by or for the benefit of the holder of a junior priority water right to prevent injury to a senior priority water right, or to provide compensation acceptable to the holder of a senior priority water right for injury caused by the diversion and use of water under the junior priority water right.” This is consistent
608 The Department’s draft Water Management Rules define “mitigation” as “[t]he result of an action taken by or for the benefit of the holder of a junior priority water right to prevent injury to a senior priority water right, or to provide compensation acceptable to the holder of a senior priority water right for injury caused by the diversion and use of water under the junior priority water right.” This is consistent