Comments Period: January 22, 2020 – February 21, 2020
SUBJECT: The U.S. Army Corps of Engineers, Sacramento District, (Corps) is evaluating a permit application to construct the Ash Creek Pipeline and Toquer Reservoir project, which would result in permanent impacts to approximately 6,728 linear feet (1.36 acres) and temporary impacts to 5,643 linear feet (2.66 acres) of waters of the United States. This notice is to inform interested parties of the proposed activity and to solicit comments.
AUTHORITY: This application is being evaluated under Section 404 of the Clean Water Act for the discharge of dredged or fill material in waters of the United States.
APPLICANT: Washington County Water Conservancy, Attn: Mr. Corey Cram, 533 E Waterworks Drive, St George, Utah 84770
LOCATION: The approximately 678-acre project site is located east of I-15, between the northern boundary of Latitude 37.41026°, Longitude -113.23525°, and the southern boundary of Latitude 37.26986°, Longitude -113.31086°, Washington County, Utah.
PROJECT DESCRIPTION: The applicant is proposing to construct the Toquer Reservoir, install four water transmission pipelines, and reconstruct the South Ash Creek Diversion Structure. The majority of the proposed project is located on Bureau of Land Management (BLM) property and will require Right of Way authorization for the pipeline and Recreation and Public Purpose authorization for the reservoir from the BLM. An environmental assessment has been completed by the BLM for the project.
The proposed reservoir would have an inundation surface area of 115 acres with a capacity of 3,638 acre-feet. A 12-acre recreation area would be constructed on the southwest side that would include a primitive campground, parking lot, boat ramp, restroom, group pavilion, and interpretive kiosks. The reservoir dam would have a maximum height of 103 feet by approximately 1,100 feet and a maximum width of 300 feet. A concrete weir and splashpad would be constructed for the spillway, and a 1,889 linear foot open channel would tie into the Anderson Junction Wash below the dam. The reservoir would permanently impact 6,703 linear feet of two ephemeral channels from the dam footprint and the inundation of these channels. The downstream channel of Anderson Wash would be truncated as a result of the dam. The reservoir would be used as a water storage facility receiving flow from the upstream Ash Creek Reservoir, the existing Leap Creek Diversion, the reconstructed South Ash Creek Diversion, and the existing Wet Sandy Diversion.
The project would also include four water transmission pipelines that would distribute water between the existing Ash Creek Reservoir and the proposed Toquer Reservoir, and existing regulating ponds. These pipelines would involve 10 channel crossings and construction disturbance to Ash Creek where the main pipeline would run parallel. The water pipelines would be installed using the trench and backfill method to a minimum depth of 8 feet with riprap placed to a minimum depth of 3 feet on the downstream side to protect the pipe from scouring. Once, installation is complete the channels would be restored to preconstruction contours. These channels disturbance would result in temporary impacts to 5,531 linear feet (2.35 acres) of intermittent channel and 112 linear feet (0.31 acre) of ephemeral channel.
The applicant’s stated purpose is: 1) to increase the availability of water for consumptive use through water collection, storage, and aquifer recharge; 2) to improve the efficiency of water conveyance and storage by preventing seepage and evaporative losses occurring in canals and reservoirs; and 3) to allow for high quality water from Toquerville Springs to be transferred from irrigation to culinary uses.
The attached drawings provide additional project details.
Environmental Setting. There are approximately 10,532 linear feet of intermittent channel and 9,135 linear feet of ephemeral channel within the 678-acre project area. The site is located at the northeastern edge of the Mojave Desert.
The reservoir area is located in a transition zone from a black brush (Coleogyne ramosissima) community to a pinyon/juniper forest. Roughly, the western third of the area is dominated with Utah juniper (Juniperus osteosperma) and black brush, while the other two thirds is dominated with black brush, wolf berry (Lycium andersonii), green ephedra (Ephedra viridis), Indigo bush (Psorothamnus fremontii) and sand sage (Artemisia filifolia).
Vegetation communities along the pipeline area varies with changes in elevation, presence of surface water, and impacts from past fires. Vegetation from Anderson Junction north to Ash Creek Reservoir can be characterizes as pinion/juniper forest. Vegetation communities south of Anderson junction are lower in elevation and dominated by sand sage, and desert almond (Prunus fasciculate). Within the pinion/juniper vegetation communities north of Anderson Junction, there are two distinctly different plant communities. The first is dominated by cottonwood (Populus fremontii) and single leaf ash (Fraxinus anomala), and was found in association with several streams. The second plant community, dominated by yerba santa (Eriodictyon angustifolium) and Dixie live oak (Quercus turbinella), was found in burned areas. Cheat grass (Bromus tectorum) and foxtail brome (Bromus rubens) occur in great density in the burned areas and throughout the project area. Salt cedar (Tamarix ramosissima), perennial pepperwood (Lepidium latifolium), and scotch thistle (Onopordum acanthium) are found along several streams within the study area.
There are two primary soil types within the project: on the north, which includes much of the area that would be inundated by the reservoir, the soils are a Veyo-Curhollow complex, which are characteristic of alluvial fans that are well-drained and have a 3 to 10 percent slope. On the southern end of the proposed project site, which would include the dam, the soils are a Pintura-Toquerville complex, which are characteristic of mountain slopes, generally have a 1 to 20 percent slope, and are considered somewhat excessively drained. Neither of these sandy soil types are hydric, nor are they frequently flooded.
Alternatives. The applicant has not provided information concerning project alternatives. Additional information concerning project alternatives may be available from the applicant or their agent. Other alternatives may develop during the review process for this permit application. All reasonable project alternatives, in particular those which may be less damaging to the aquatic environment, will be considered.
Mitigation. The Corps requires that applicants consider and use all reasonable and practical measures to avoid and minimize impacts to aquatic resources. If the applicant is unable to avoid or minimize all impacts, the Corps may require compensatory mitigation. The applicant has proposed to preserve and dedicate 4.4 acres of land along the Virgin River to the Virgin River Program.
OTHER GOVERNMENTAL AUTHORIZATIONS: Water quality certification or a waiver, as required under Section 401 of the Clean Water Act from the Utah Division of Water Quality is required for this project. The applicant has indicated they have applied for certification. Projects are usually certified where the project may create diffuse sources (non-point sources) of wastes which will occur only during the actual construction activity and where best management practices would be employed to minimize pollution effects. A person who wishes to challenge such certification may only raise an issue or argument during an adjudicatory proceeding that is raised during the public comment period and is supported with sufficient information or documentation to enable the Director to fully consider the substance and significance of the issue. Utah Code Ann. 19-1-301.5 can be viewed at the following URL: https://le.utah.gov/xcode/Title19/Chapter1/19-1-S301.5.html. Written comments specific to the Section 401 Water Quality Certification relative to this public notice should be submitted to Leanna Littler, Utah Division of Water Quality, P.O. Box 144870, Salt Lake City, Utah 84114-4870, or email@example.com on or before February 21, 2020.
HISTORIC PROPERTIES: The Bureau of Land Management is lead federal agency responsible for compliance with Section 106 of the National Historic Preservation Act. The Corps will act as cooperating agency and adopt determinations, as appropriate.
ENDANGERED SPECIES: The Bureau of Land Management is lead federal agency responsible for compliance with Section 7 of the Endangered Species Act. The Corps will act as cooperating agency and adopt determinations, as appropriate.
ESSENTIAL FISH HABITAT: The proposed project would not adversely affect Essential Fish Habitat (EFH) as defined in the Magnuson-Stevens Fishery Conservation and Management Act.
The above determinations are based on information provided by the applicant and our preliminary review.
EVALUATION FACTORS: The decision whether to issue a permit will be based on an evaluation of the probable impacts, including cumulative impacts, of the described activity on the public interest. That decision will reflect the national concern for both protection and utilization of important resources. The benefit, which reasonably may be expected to accrue from the described activity, must be balanced against its reasonably foreseeable detriments. All factors which may be relevant to the described activity will be considered, including the cumulative effects thereof; among those are conservation, economics, aesthetics, general environmental concerns, wetlands, historic properties, fish and wildlife values, flood hazards, floodplain values, land use, navigation, shoreline erosion and accretion, recreation, water supply and conservation, water quality, energy needs, safety, food and fiber production, mineral needs, consideration of property ownership and, in general, the needs and welfare of the people. The activity's impact on the public interest will include application of the Section 404(b)(1) guidelines promulgated by the Administrator, Environmental Protection Agency (40 CFR Part 230).
The Corps is soliciting comments from the public, Federal, State, and local agencies and officials, Indian tribes, and other interested parties in order to consider and evaluate the impacts of this proposed activity. Any comments received will be considered by the Corps to determine whether to issue, modify, condition, or deny a permit for this proposal. To make this decision, comments are used to assess impacts on endangered species, historic properties, water quality, general environmental effects, and other public interest factors listed above. Comments are used in the preparation of an Environmental Assessment and/or an Environmental Impact Statement pursuant to the National Environmental Policy Act. Comments are also used to determine the need for a public hearing and to determine the overall public interest of the proposed activity.
SUBMITTING COMMENTS: Written comments, referencing Public Notice SPK-2011-01121 must be submitted to the office listed below on or before February 21, 2020.
Hollis Jencks, Project Manager
US Army Corps of Engineers, Sacramento District
Bountiful Regulatory Office
533 West 2600 South, Suite 150
Bountiful, Utah 84010
The Corps is particularly interested in receiving comments related to the proposal's probable impacts on the affected aquatic environment and the secondary and cumulative effects. Anyone may request, in writing, that a public hearing be held to consider this application. Requests shall specifically state, with particularity, the reason(s) for holding a public hearing. If the Corps determines that the information received in response to this notice is inadequate for thorough evaluation, a public hearing may be warranted. If a public hearing is warranted, interested parties will be notified of the time, date, and location. Please note that all comment letters received are subject to release to the public through the Freedom of Information Act. If you have questions or need additional information please contact the applicant or the Corps' project manager Hollis Jencks, (801) 295-8380 X 8318, Hollis.G.Jencks@usace.army.mil.
Attachments: 12 drawings