Department of Environmental Quality To protect, conserve, and enhance the Quality of Wyoming s environment for the benefit of current and future generations Dave Freudenthal, Governor John Corra, Director CATEGORICAL USE ATTAINABILITY ANALYSIS FOR ARTIFICIALLY CONSTRUCTED CANALS AND DITCHES Purpose September 1, 2004 The purpose of this categorical Use Attainability Analysis (UAA) is to provide the required support for the Class 4A designation assigned to irrigation canals and ditches throughout the State. Chapter 1 of the Wyoming Water Quality Rules and Regulations establishes classifications for all surface waters of the state. Each classification refers to the uses that are designated on the associated waters and the water quality criteria necessary to assure the attainment of each designated use. Specifically, Section 4(d)(i) creates a category of waters (Class 4A) to which the statewide criteria for aquatic life protection do not apply. Section 4(d)(i) states: Class 4A waters are artificial canals and ditches that are not known to support fish populations. The rules provide that prior to classifying a water as 4A, the department will document the reasons for that decision in a UAA and provide an opportunity for public comment on the determination. The purpose of this document is to meet the UAA and public notice requirements for this category of man-made waters rather than addressing these created waters individually. Basis for the Class 4A Designation The waters that are covered by this categorical UAA are artificially constructed irrigation canals and ditches that: 1) are not constructed in natural drainages and are specifically managed for agricultural purposes; 2) are dewatered for significant periods of the year; 3) do not support existing fishery uses or aquatic resource values (i.e., there is no more than incidental occurrence of aquatic organisms, and those aquatic organisms that do occur are lost when the canal or ditch is dewatered); and 4) lack the flow and aquatic habitat needed to support an aquatic life use.
In making this classification determination, the Water Quality (Division) is relying upon the use attainability factor in Section 33(b)(v) of the Chapter 1 rules, which allows for the removal of an aquatic life designation where: "Physical conditions related to the natural features of the water body, such as lack of a proper substrate, cover, depth, pools riffles, and the like, unrelated to water quality, preclude attainment of the classification or use." The information necessary to establish this factor for the purpose of classifying a water "4A" should consist of information showing that significant periods of dewatering and physical habitat limitations preclude attaining an aquatic life use for this category of man-made waters. That information was collected during site visits to a representative number of irrigation canals and ditches in October, 2003. The canals and ditches visited included a range of sizes and were scattered throughout the State, with representatives in most of the major river drainages. These visited canals and ditches, therefore, provide a representative subset of expected flow and habitat conditions for irrigation canals and ditches state-wide. The October field evaluation occurred shortly (within days) after active diversion had ceased for the season for many of the canals and ditches. In those cases, the canals and ditches were either completely dewatered (dry), or where isolated pools remained, it was clear those pools would soon disappear. In general, the man-made nature of these canals and ditches is such that these engineered water conveyances provide little in the way of suitable aquatic habitat, i.e., these structures have relatively straight channels with steep sides, sandy or silty bottoms, no cover and no riffle/pool complexes. At the time of the field evaluation, water was still being diverted to several canals. Nevertheless, even though the water had not yet been shut off and the canals still carried water, the physical habitat limitations for this category of waters were still evident. Below is a series of photographs taken during the field evaluation showing the flow and habitat limitations for this category of waters. 2
List of Photographs (taken October 20 to 24, 2003) North Platte River Basin Photo 1 Photo 2 Photo 3 Photo 4 Photo 5 Photo 6 Photo 7 Photo 8 Photo 9 Photo 10 Photo 11 Fort Laramie Canal (near Torrington) Interstate Canal (near Torrington) Interstate Canal (near Lingle) Rock Ranch Canal (near Lingle) Fort Laramie Canal (near Lingle) Number 2 Canal (Wheatland) Bellamy Ditch) (near Laramie) Pioneer Canal (near Laramie) North Canal (near Laramie) Markle Ditch (near Centennial) Casper Canal (near Casper) Powder River Basin Photo 12 Photo 13 Redman Ditch (near Buffalo) Splasher Ditch (near Buffalo) Big Horn River Basin Photo 14 Photo 15 Photo 16 Photo 17 Photo 18 Photo 19 Photo 20 Photo 21 Photo 22 Photo 23 Photo 24 Photo 25 Photo 26 Upper Hanover Canal (near Worland) Lower Hanover Canal (near Worland) Big Horn Canal (near Worland) Beck-Allen Canal (near Burlington) Farmers Canal (near Burlington) Bench Canal (near Burlington) Shell Canal (near Greybull) Lovell Canal (near Lovell) Sidon Canal (near Deaver) Frannie Canal (near Frannie) Pilot Canal (near Riverton) LeClair Canal (near Riverton) Wyoming Canal (near Pavillion) Snake River Basin Photo 27 East Side Canal (near Thayne) Bear River Basin Photo 28 Photo 29 Chapman Ditch (near Evanston) Tunnel Ditch (near Evanston) 3
Photo 1 Fort Laramie Canal at the Highway 85 crossing north of Hawk Springs Wyoming. North Platte River Basin. Photo 2 Interstate Canal north of Torrington, Wyoming. North Platte River Basin. 4
Photo 3 Interstate Canal near Lingle, Wyoming. North Platte Basin Photo 4 Rock Ranch Canal below headgate on the North Platte River. Headgate closed for the season. Standing water resulting from a seep in the headgate structure. 5
Photo 5 Fort Laramie Canal west of Lingle, Wyoming. North Platte River Basin. Photo 6 Number 2 Canal in Wheatland, Wyoming. Laramie River Watershed. 6
Photo 7 Bellamy Ditch northwest of Laramie, Wyoming. North Platte River Basin. Photo 8 Pioneer Canal at Highway 130 crossing west of Laramie, Wyoming. North Platte River Basin. 7
Photo 9 North Canal at Highway 130 crossing west of Laramie, Wyoming. North Platte River Basin. Photo 10 Markle Ditch at Highway 130 crossing near Centennial, Wyoming. North Platte River Basin. 8
Photo 11 Casper Canal west of Casper, Wyoming. North Platte River Basin. Photo 12 Redman Ditch just below diversion structure on Clear Creek near Buffalo, Wyoming. Powder River Basin. Active diversion ceased, standing water in the canal caused by a seep in the diversion structure. 9
Photo 13 Splasher Ditch near Buffalo, Wyoming Wastewater Treatment Facility. Powder River Basin. Photo 14 Upper Hanover Canal southeast of Worland, Wyoming. Big Horn River Basin. 10
Photo 15 Lower Hanover Canal south of Worland, Wyoming. Big Horn River Basin. Photo 16 Big Horn Canal, Hwy 433 crossing just west of Worland, Wyoming. Big Horn River Basin. 11
Photo 17 Beck-Allen Canal at State Hwy 30 crossing south of Burlington, Wyoming. Still actively irrigating at the time of photo. Big Horn River Basin. Photo 18 Farmers Canal at State Hwy 30 crossing north of Burlington, Wyoming. Still actively irrigating at the time of photo. Big Horn River Basin. 12
Photo 19 Bench Canal at State Hwy 30 crossing north of Burlington, Wyoming. Big Horn River Basin. Photo 20 Shell Canal near Highway 14 east of Greybull, Wyoming. Still actively irrigating at the time of photo. Big Horn River Basin. 13
Photo 21 Lovell Canal east of Lovell, Wyoming. Active diversion shut off but canal still holding some standing water. Big Horn River Basin. Photo 22 Sidon Canal at Highway 130 crossing between Deaver and Cowley, Wyoming. Big Horn River Drainage. 14
Photo 23 Frannie Canal at the extreme end, east of Frannie Wyoming. Irrigation recently ceased, standing water still in canal. Big Horn River Basin. Photo 24 Pilot Canal at the Highway 26 crossing between Shoshoni and Riverton, Wyoming. Wind River watershed. 15
Photo 25 LeClair Canal at the Airport Road crossing just north of Riverton, Wyoming. Wind River watershed. Photo 26 Wyoming Canal west of Pavillion, Wyoming. Irrigation recently ceased, some standing water still in canal. Wind River watershed. 16
Photo 27 East Side Canal in Thayne, Wyoming, Still actively irrigating at the time of the photo. Snake River Basin. Photo 28 Chapman Ditch on highway 89 crossing north of Evanston, Wyoming. Still actively irrigating at the time of the photo. Bear River Basin. 17
Photo 29 Tunnel Ditch north of Evanston, Wyoming. Still actively irrigating at the time of the photo. Bear River Basin. A small number of canals and ditches are currently designated in the Wyoming Surface Water Classification List as Class 2B. These are agricultural canals that are known to temporarily support game fish species. They are designated as Class 2 in order to ensure adequate human health protection to people who may catch and consume those fish. It is important to note that the Wyoming Game and Fish Department (WGFD) does not manage irrigation canals and ditches for fishery purposes Rather, the WGFD's goal is to restrict fish entry into canals and ditches. Because the annual dewatering of the irrigation canals and ditches kills the fish, loss of fish to canals and ditches is considered an impact to the State's fishery resource. A limited number of canals and ditches are also receiving waters for NPDES-permitted discharges, and those canals and ditches were included in the subset visited in October, 2003. A review of the permits and information gathered during the site visits showed the permits were either inactive, or where active, discharges occurred only during the period of active diversion. The existing permits, therefore, would not alter the conclusion of this UAA that Class 4A is the appropriate classification for irrigation canals and ditches. 18
Conclusion The waters that are covered by this categorical UAA are artificially constructed irrigation canals and ditches, and the information presented in this categorical UAA supports the designation of Class 4A for this category of waters, where the canal or ditch: 1) is not constructed in a natural drainage and is specifically managed for agricultural purposes; 2) is dewatered for significant periods of the year; 3) does not support existing fishery uses or aquatic resource values (i.e., there is no more than incidental occurrence of aquatic organisms, and those aquatic organisms that do occur are lost when the canal or ditch is dewatered); and 4) lacks the flow and aquatic habitat needed to support an aquatic life use. This conclusion is supported by an evaluation of a representative subset of canals and ditches scattered throughout the State. Based on this UAA, irrigation canals and ditches, meeting the conditions outlined above, are Class 4A. No further analysis is required in making such a designation. Nevertheless, this general presumption can be rebutted, on a site-specific basis, and the public is encouraged to provide information where that information would call into question the appropriateness of the Class 4A designation for a specific canal or ditch. Public Participation All interested persons are invited to submit written comments and/or recommendations regarding this use attainability determination by October 1, 2004. Written comments may be directed to Bill DiRienzo, DEQ/WQD, Herschler Building, Cheyenne, Wyoming, 82002; phone: (307) 777-7081; Fax: 307-777-5973. Emailed comments will not be accepted. After an evaluation of all comments received, the administrator of the Water Quality Division will publish a final determination and begin implementation. WJD/bb/4-0845.doc 19