36.12.1902 CHANGE APPLICATION - HISTORIC USE
(1) The description of the historic information is related to a date that is dependent on the type of water right being changed. The following dates are applicable for each type of water right:
(a) historic information for a statement of claim must be described as it was used prior to July 1, 1973, unless the Water Right Claim was subject to a previous change in which case it is the date of completion of the change;
(b) historic information for a provisional permit must be described as it was
used at the filing date of the completion notice;
(c) historic information for a certificate of water right must be described as it
was used at the filing date of the completion notice;
(d) historic information for an exempt or nonfiled water right must be
described as it was completed prior to July 1, 1973; and
(e) when a change application has been granted on or after July 1, 1973, the department may request additional historic information for a statement of claim as it was used prior to July 1, 1973.
(2) Final Water Court approved stipulations and master's reports related to the water right being changed must be referenced with the application; however, this information or an abstract of a water right from the department or the Montana Water Court by itself is not sufficient to prove the existence or extent of the historical use.
(3) The amount of water being changed for each water right cannot exceed or increase the flow rate historically diverted under the historic use, nor exceed or increase the historic volume consumptively used under the existing use.
(a) The department may use column H in Table 1 for proposed irrigation to compare the historic consumptive use (HCU) to the amount of water being changed.
(4) The department shall compare historical acres irrigated to acres identified as irrigated in the Water Resources Survey, if available for the place of use. If the Water Resources Survey does not support the historical irrigation alleged in the application, the applicant shall explain why. Information from irrigation journals, logs, or old aerial photographs can be submitted for consideration.
(5) For an application to change multiple irrigation water rights, the total number of acres for each water right located within the place of use must be identified.
(6) For an application to change water rights that overlap the historic place of use, an applicant shall include those water rights in the change application or shall explain how each of the water rights has been historically used and how the unchanged water rights will be used if the change authorization were granted. If water will continue to be used at the historic place of use, the applicant shall explain how the continued use will not increase the combined historic maximum diverted flow rate, the historic diverted volume, and the historic consumptive volume.
(7) The department will corroborate the historic use, including the following of each water right being changed:
(a) water right number and the priority date;
(b) most recent year the water right was used;
(c) historic point of diversion;
(d) historic period of diversion;
(e) historic means of diversion;
(f) typical historic diversion schedule and operation pattern;
(g) means of conveyance;
(h) historic ditch capacity;
(i) maximum historic flow rate diverted from each point of diversion and how the amount was determined;
(j) historic place of use for each purpose;
(k) maximum number of acres historically irrigated;
(l) typical historic period of use for each purpose;
(m) annual or monthly historic diverted volume and how this amount was determined;
(n) the annual or monthly historic consumptive volume for each purpose;
(i) for irrigation, an applicant may choose to use the methodology described in (16); and
(ii) for irrigation, an applicant who chooses not to use the methodology described in (16), shall provide the factual basis for the historic consumptive volume calculation and why the historic consumptive use is less than or greater than the methodology described in (16);
(o) the historic efficiency including the diversion, conveyance, and overall system;
(p) the legal land description of a reservoir;
(q) the maximum volume in acre-feet of stored water;
(r) evaporation loss of stored water (evaporation standards can be found in ARM 36.12.116);
(s) maximum number of times a reservoir was filled during a year; and
(t) maximum period of time when water was legally collected for storage.
(8) The following information may be used by the department to establish the requirements under (7):
(a) aerial photographs depicting irrigated land:
(i) 1979, 1997, and 2005 photos showing the irrigated land;
(b) aerial or other photographs showing diversion or conveyance structures;
(c) Water Resources Survey book information;
(d) Water Resources Survey field notes;
(e) water commissioner field notes;
(f) Natural Resources Conservation Service (NRCS) information, such as field specific soils information;
(g) affidavits from persons with first-hand knowledge of historic use;
(h) calculation of historic ditch capacities;
(i) description of irrigation equipment, field treatments, means of conveyance, control structures, and other onsite features related to water use;
(j) description of water supply availability;
(k) log books or diaries of previous irrigators or farm operations, crop yield records, or diversion records; or
(l) an evaluation of the seniority of the water right in relation to other users.
(9) The annual or monthly historic diverted volume must be based on the appropriator's typical historic operation of their diversion, irrigation, and harvest schedule throughout the period of diversion and the period of use. If applicable, in addition to the information required in 36.12.1902(7), if a secondary diversion from a ditch or reservoir exists, an applicant shall identify the diversion means and the typical operation of that secondary diversion.
(10) The department shall calculate the historic diverted volume for water rights with the purpose of irrigation using the following equation: Historic Diverted Volume = (Volumehistoric consumptive use/On-farm efficiency) + Volumeconveyance loss:
(a) "conveyance loss" means the portion of water diverted at the headgate that does not arrive at the irrigated place of use due to seepage and evapotranspiration from the ditch;
(b) "seepage loss" means ((flow area)*(ditch length)*(loss rate)*(days))/43,560 ft2/ac; and
(c) "on-farm efficiency" refers to the percent of the water delivered to the field that is used by the crop.
(11) If the applicant chooses not to use the methodology in (10), they shall provide additional information on the Historic Water Use Addendum.
(12) Historic consumptive volume must be based on the acre-feet of water used for the beneficial purpose, such as water transpired by growing vegetation, evaporated from soils or water surfaces, or incorporated into products that do not return to ground or surface water.
(13) The following may be used to calculate ditch capacity, historic available water supply, and reservoir capacity:
(a) Manning's equation;
(b) Orsborn's equation;
(c) Blaney-Criddle equation; and
(d) the department will determine the acceptability of other reports or methods on a case-by-case basis.
(14) The historic consumptive use methodology that the department shall use to determine historic consumptive use for water rights with a purpose of irrigation is based on data from the United States Department of Agriculture (USDA) National Agricultural Statistics Service (NASS), and generated using the USDA NRCS Irrigation Water Requirements (IWR) program. If the applicant chooses not to accept the methodology used by the department, the applicant shall provide additional information on the Historic Water Use Addendum.
(15) IWR Data for Seasonal Alfalfa Evapotranspiration County Management Factor are shown in Table 1 and will be used by the department to identify the historic consumptive volume unless additional information is provided by the applicant on the Historic Water Use Addendum. If this table is used to establish the historic consumptive volume, the department will recognize that volume as a reasonable calculation, unless a valid objection is received which offers proof that the volume is inaccurate.
(16) To determine the historic consumptive volume using the table, the department will complete the following steps:
(a) determine which weather station (column B) is the most representative for the place of use (column C). The most representative weather station may not be in the county of the place of use, but must be nearby and about the same elevation and climatic conditions as the irrigated acres. A map showing the weather stations is located on the Internet at: http://dnrc.mt.gov/wrd/water_rts/default.asp;
(b) find the evapotranspiration inches based on whether the historic irrigation is flood, wheeline, handline, or center pivot, to estimate the historic IWR (columns D or E);
(c) identify the county in which the irrigated acres are located to determine the county management factor percentage (column F or G);
(d) multiply the IWR estimate found in column D or E by the management factor percentage in column F or G. The result is the number of inches used per irrigated acre;
(e) multiply the number of total acres within the historic place of use by the county adjusted inches used per irrigated acre calculated in (d) above to determine the historic consumptive inches for those acres; and
(f) divide the cumulative historic consumptive inches from (e) by 12 to determine the cumulative historic consumptive acre-feet for the total acres.
(g) If the historic consumptive volume determined by this methodology exceeds the historic diverted amount, the department may request additional information in order to resolve the discrepancy. This may result in a reduction of the consumptive volume.
Table 1 - Montana County Weather Station IWR Data for Seasonal Alfalfa Evapotranspiration and Montana County Management Factor.
1The 1997-2006 county management factor was calculated to be slightly greater than 100%, therefore the 1997-2006 Management Factor is set to 100%.
(17) In addition to the amount determined by the methodology described in (14) and (15), the department will add the following consumptive loss components to account for irrecoverable losses at the field:
(a) 5% of the volume applied to the field for flood systems; and
(b) 10% of the volume applied to the field for sprinkler systems.
History: 85-2-112, 85-2-113, 85-2-302, MCA; IMP, 85-2-302, 85-2-401, 85-2-402, 85-2-407, 85-2-408, 85-2-436, MCA; NEW, 2004 MAR p. 3036, Eff. 1/1/05; AMD, 2009 MAR p. 2259, Eff. 11/26/09; AMD, 2012 MAR p. 2071, Eff. 10/12/12; AMD, 2013 MAR p. 1344, Eff. 7/26/13.