Wellsville Canyon Plan-EIS

Wellsville Canyon Watershed Plan and Environmental Impact Statement for Improvements in the Wellsville Mountains Watershed

Sponsor: Cache Water District
Co-sponsors: Wellsville City Irrigation Company, Wellsville City, Mendon City, Wellsville-Mendon Conservation District, Mendon North Irrigation Company, Mendon Central Irrigation Company, Mendon Second North Irrigation Company, Greater Mendon Irrigation Company, Wellsville East Field Irrigation & Canal Company, Mendon South Irrigation Company, Cache County

Page updated: May 7, 2024  (This page will continue to be updated as the project progresses.)

Note: Previously referred to as the Wellsville-Mendon Plan-EA. Some early project materials use this name.

◆ Notice of Intent to Prepare an Environmental Impact Statement

The Natural Resources Conservation Service (NRCS) Utah State Office, in cooperation with the U.S. Bureau of Reclamation (USBR), the Environmental Protection Agency (EPA), and Cache Water District (project sponsor), announces its intent to prepare a watershed plan for the Wellsville Canyon Watershed Plan located within the Little Bear River Watershed in Cache County, Utah. The proposed Wellsville Canyon Watershed Plan will examine alternative solutions to provide flood protection and conveyance infrastructure, reduce irrigation water loss, enhance recreational facilities, and reduce erosion and nutrient loading to the Little Bear River in Wellsville and Mendon cities and portions of unincorporated Cache County. NRCS is requesting comments to identify significant issues, potential alternatives, information, and analyses relevant to the proposed action from all interested individuals, Federal and State agencies, and Tribes.

Notice of Intent: Wellsville Canyon Watershed Plan-EIS NOI

NRCS began an Environmental Assessment (EA) for the proposed Project in mid-2021. As the EA developed, the project team completed public and agency scoping, development of the initial design alternatives and review of those alternatives based on the purpose and need for the project. Based on programmatic project scale requirements, NRCS determined an EIS was necessary and is seeking further public comment to help determine the range of actions, alternatives, and impacts to be evaluated and included in the EIS. Written or emailed comments can be submitted through June 7, 2024, and should be directed to:

Mail:   Wellsville Canyon Watershed Plan-EIS
c/o Landon Richins
1276 South 820 East, Suite 100
American Fork, Utah 84003

Email: [email protected]  

Please note that all comments received previously during the Environmental Assessment scoping comment period in 2021 will be included and do not need to be resubmitted. Previous comments submitted can be reviewed in the Scoping Report at the bottom of this page. Water resource concerns and alternatives previously identified in the EA are shown below.

Following the public comment period, the planning process will continue to move forward with development of alternatives and the alternative analysis required for the EIS. The Draft EIS is anticipated to be available Summer 2024, which will include another public comment period.


Purposes and Project Objectives

The primary purposes and objectives for watershed planning and preparation of this EIS are to:

  • Provide flood control to the Cities of Wellsville, Mendon, and portions of unincorporated Cache County from flooding that occurs from large thunderstorms and rain on frozen ground events in the valley.
  • Provide more reliable management of agricultural water in the area by constructing a more efficient irrigation delivery system to mitigate current seepage losses; and
  • Enhance recreational opportunities within the project area.

Watershed planning is authorized under Public Law 83–566, the Watershed Protection and Flood Prevention Act of 1954, as amended, and Public Law 78–534, the Flood Control Act of 1944.


Project Need ― Current Resource Concerns
Flood Protection
  • Inadequate flood capacity through Wellsville, Mendon, and areas of unincorporated Cache County
  • Address historic flooding of homes and roads
  • Reduce erosion and nutrient loading to the Little Bear River

The project will reduce flood risks and improve public safety in the watershed. Furthermore, it will greatly reduce flooding concerns associated with intense rain-on-snow and/or frozen ground events within the project area. More dependable floodwater management will benefit homes, businesses, agricultural fields, roads, and public utilities in the area.

Agricultural Water Management
  • Improve water management and measurement
  • Reduce demand on the culinary water systems
  • Reduce seepage loss in existing earthen conveyance systems

The project will implement improved culinary and agricultural water conservation techniques in the watershed. A more efficient irrigation delivery system within Mendon City and Wellsville City will help mitigate the heavy seepage losses experienced by the current earthen canal irrigation distribution systems. The project improvements will also reduce demand for the existing culinary water systems within the watershed and capital expenditures to meet peak summer irrigation demands.


The project will address limited public recreational facilities and opportunities within the watershed available for the growing population of Cache County. Recreational improvements will provide residents with a higher quality of life and will increase the public’s well-being by providing new opportunities for leisure and enjoyment.


Preliminary Proposed Action and Alternatives

The watershed-focused planning area is approximately 70,845 acres. NRCS will evaluate a minimum of two action alternatives and the no action alternative in the Draft EIS. NRCS will provide technical and financial assistance for the proposed project through the NRCS Watershed Protection and Flood Prevention Program, and NRCS will also design and implement a selected alternative. Possible alternatives are:

Alternative 1—No Action Alternative

Taking no action would consist of activities carried out if no federal action or funding were provided. This alternative would not address flooding into the canals. The canals would continue to overtop during rain-on-snow events, and flooding in the project area would continue. The canals would be maintained in their existing condition as earthen channels, and irrigation conveyance within the communities of Wellsville and Mendon would continue unchanged. The additional recreational access to Wellsville Reservoir would not be built. Additionally, erosion and sedimentation from the alluvial plains above the canals would continue unaltered under this alternative. The existing project infrastructure would continue to operate in its current condition and would not improve flood control, conserve irrigation water, improve recreational access, or reduce watershed erosion as described above. Residents would continue to use culinary water for irrigation (i.e., watering lawns and gardens), putting stress on existing water supply and infrastructure.

Alternative 2—Proposed Action

The proposed action is to enclose the Wellsville-Mendon Canal (Lower Canal) and convey water through piping in Wellsville and Mendon cities and part of unincorporated Cache County, Utah. The existing Wellsville-Mendon Canal would be improved with the addition of open channel overflow systems at 2900 South or 3400 South (Unincorporated Cache County) and 200 South (Mendon City). This would be accomplished through a combination of conduits and channels to convey floodwaters from the west side of Cache Valley between Wellsville and Petersboro to the natural floodplain of the Little Bear River east of the communities. This proposed action would continue to divert the water for the Wellsville-Mendon Conservation District from below Hyrum Reservoir at the existing diversion points. This proposed action would also enclose and pipe a portion of the Wellsville Eastfield Canal beginning at the existing diversion at the base of Hyrum Dam and passing through Hyrum and ending in unincorporated Cache County, Utah. This proposed action would also pressurize Wellsville City Irrigation Company’s irrigation system within Wellsville City and within Mendon City’s irrigation system managed by the Mendon North, Mendon Central, Mendon South, Mendon Second North, and Greater Mendon Irrigation companies. This proposed action would also install regulating ponds to stabilize peak demands on the pressurized irrigation systems. A new access ramp limited to non-motorized personal watercraft would be constructed at Wellsville Reservoir for recreational activities. Additionally, a reflecting pond may be constructed as an additional recreation component near Mendon cemetery.

Alternative 3—Lining Alternative

All project measures would be the same as Alternative 2 with the following exceptions. Alternative 3 would line and increase the capacity of the Wellsville-Mendon Canal (Lower Canal) to carry both irrigation and flood water from the west alluvial plains between Wellsville and Petersboro in Cache County instead of enclosing and piping. This would include the reconstruction of the existing Murray Spring overflow structure and the addition of overflow structures at 2900 South or 3400 South in unincorporated Cache County and 200 South in Mendon City.

◆ Project Watershed Map and Potential Disturbance Areas Map

Wellsville Canyon Watershed Map

Wellsville Canyon Potential Disturbance Areas Map

◆ Project Description

The United States Department of Agriculture Natural Resources Conservation Service (USDA-NRCS), with assistance from Cache Water District as the project sponsor, and several co-sponsors—Wellsville City Irrigation Company, Wellsville City, Mendon City, Wellsville-Mendon Conservation District, Mendon North Irrigation Company, Mendon Central Irrigation Company, Mendon Second North Irrigation Company, Greater Mendon Irrigation Company, Wellsville East Field Irrigation & Canal Company, Mendon South Irrigation Company, and Cache County—are considering proposed improvements within the Wellsville Canyon and Threemile Creek Watersheds, Cache County, UT.

The proposed project would prevent or reduce flooding, enhance wildlife habitat, and improve irrigation water delivery. Conceptual improvements may include:

  1. Flood Prevention
    • Culvert replacements
    • Channel stabilization measures
    • Detention basins
  2. Agricultural Water Management
    • Pressurized secondary irrigation system to improve reliable irrigation water supply and provide sustainable conveyance system
    • Diversion structures
  3. Recreation
    • Opportunities at Wellsville Reservoir

◆ Project Location

Map of the project watershed area: Wellsville Canyon Watershed Map

◆ NEPA Analysis

NRCS, as the lead federal agency, is initiating National Environmental Policy Act (NEPA) analysis in the form of a Watershed Plan and Environmental Assessment (Plan-EA) to analyze impacts to the natural and human environment from this project. The Plan-EA will comply with the Council on Environmental Quality’s regulations at 40 CFR Parts 1500-1508 and the Natural Resources Conservation Service Regulations (7 CFR Part 650), which require an evaluation of potential environmental impacts associated with federal projects and actions.

Update: This project has been updated from an Environmental Assessment (EA) to an Environmental Impact Statement (EIS).

Under the National Environmental Policy Act of 1969 (NEPA), any project which receives federal funding must undergo an environmental impact analysis to ensure that no unnecessary irreversible or damaging practices occur as a result of the project. Compliance with NEPA can come in three different ways: an Environmental Assessment (EA), an Environmental Impact Statement (EIS), or a Categorical Exclusion (CatEx).

A Categorical Exclusion is applied to federal projects which are deemed to have negligible environmental impacts and are exempt from further analysis.

Environmental Assessments are documents which are written to evaluate all existing resources in a project area, develop all possible project alternatives which would fulfill the Purpose and Need, evaluate the environmental consequences each alternative would have, select a Preferred Alternative, and issue a Finding of No Significant Impact (FONSI) statement. Under an EA, only two alternatives are evaluated, the NEPA No-Action Alternative and the Proposed Action.

An Environmental Impact Statement follows the same process as an EA but includes the evaluation of multiple alternatives in addition to the NEPA No-Action Alternative. An EIS also typically covers projects which are larger in scale that may have more significant environmental consequences. Upon completion of an EIS, the federal agency will issue a Record of Decision (ROD) instead of a FONSI since some impacts are likely to occur under EIS projects.

An EA may progress to an EIS for several reasons, including exceedance of a federal funding cap for an EA or if the project will have larger and more consequential environmental impacts to proceed. This project has progressed to an EIS due to the exceedance of the federal funding cap for the EA.

◆ Current Status

The NOI has been published to the Federal Register. The project is currently in the alternative development and analysis phase.

◆ Project Schedule
  • Scoping Public Comment Period :: April 27, 2021 — May 27, 2021

You can click here to view the Scoping Report. (The page may take a few minutes to load due to the large file size of the report. We recommend using the Google Chrome browser. Thank you for your patience!)

  • Scoping Public Virtual Open House :: May 11, 2021

You can click here to see the meeting flyer, presentation, and a recording of the meeting.

  • Alternative Development and Analysis :: Ongoing
  • Preparation of Draft Watershed Plan – Environmental Impact Statement (Draft Plan-EIS) :: Spring 2023 – Summer 2024
  • Draft Plan-EIS Public Comment Period (30 days) :: Pending
  • Preparation of Final Plan-EIS and Record of Decision (Final Plan-EIS and ROD) :: Summer 2025
  • Issue of Record of Decision (ROD) :: 2025

◆ Contact Information

Landon Richins — Franson Civil Engineers
1276 South 820 East Suite 100
American Fork, UT 84003
Phone: 801-756-0309
Email: [email protected]

Anthony Beals – USDA-NRCS
125 South State Street Room 4010
Salt Lake City, UT 84138
[email protected]

Derek Hamilton – USDA-NRCS
125 South State Street Room 4010
Salt Lake City, UT 84138
[email protected]