Pettit Lake Creek Weir Project
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Pettit Lake Creek Weir Project United States Department of Notice of Proposed Action Agriculture Forest Service February 2020 Sawtooth National Recreation Area Sawtooth National Forest Blaine County, Idaho Pettit Lake Creek Weir In accordance with Federal civil rights law and U.S. Department of Agriculture (USDA) civil rights regulations and policies, the USDA, its Agencies, offices, and employees, and institutions participating in or administering USDA programs are prohibited from discriminating based on race, color, national origin, religion, sex, gender identity (including gender expression), sexual orientation, disability, age, marital status, family/parental status, income derived from a public assistance program, political beliefs, or reprisal or retaliation for prior civil rights activity, in any program or activity conducted or funded by USDA (not all bases apply to all programs). Remedies and complaint filing deadlines vary by program or incident. Persons with disabilities who require alternative means of communication for program information (e.g., Braille, large print, audiotape, American Sign Language, etc.) should contact the responsible Agency or USDA’s TARGET Center at (202) 720-2600 (voice and TTY) or contact USDA through the Federal Relay Service at (800) 877-8339. Additionally, program information may be made available in languages other than English. To file a program discrimination complaint, complete the USDA Program Discrimination Complaint Form, AD- 3027, found online at http://www.ascr.usda.gov/complaint_filing_cust.html and at any USDA office or write a letter addressed to USDA and provide in the letter all of the information requested in the form. To request a copy of the complaint form, call (866) 632-9992. Submit your completed form or letter to USDA by: (1) mail: U.S. Department of Agriculture, Office of the Assistant Secretary for Civil Rights, 1400 Independence Avenue, SW, Washington, D.C. 20250-9410; (2) fax: (202) 690-7442; or (3) email: [email protected]. USDA is an equal opportunity provider, employer and lender. 2 Notice of Proposed Action Request for Comments Comments on this Notice of Proposed Action for the Pettit Lake Creek Weir Project may be submitted by facsimile, U.S. mail, or hand-delivery to the address listed below. Office hours for hand-delivered comments are 8:30 a.m. to 5:00 p.m., Monday through Friday, excluding holidays. Electronic comments can be submitted by email message to comments-intermtn- [email protected]. These comments must be submitted in a format such as plain text (.txt), rich text (.rtf), Adobe (.pdf), or Word (.doc). Please indicate “Pettit Lake Creek Weir Project” in the subject line. Please Note that comments are a matter of public record and will be released in their entirety if requested. A legal notice will be published in the Challis Messenger newspaper and is the exclusive means for calculating the comment period. Comments will be accepted for 30-days following the publication of the legal notice. Those wishing to comment should not rely upon dates or timeframe information provided by any other source. Individuals and entities wishing to be eligible to object must meet the information requirements of 36 CFR 218 Subparts A and B. It is the responsibility of persons providing comments to submit them by the close of the comment period. Only those who submit timely and specific written comments are eligible to file an objection under §218. For further questions regarding this project, please contact: Whitney Burgess Sawtooth National Recreation Area 5 North Fork Canyon Road Ketchum, Idaho 83340 Email: [email protected] Phone: 208-727-5008 Fax:208-727-5029 Introduction What is being proposed? The Shoshone-Bannock Tribes of Fort Hall have requested that the Sawtooth National Forest (SNF) authorize construction of a weir fish trap, located in Pettit Lake Creek, that replaces an existing weir built in 1995 (Figure 1). The plan is to construct the new weir in the same general location as the existing weir. Construction will include a new sill, new abutments, and a small parking area and walkway adjacent to the creek. Another part of the proposed work is to remove the two concrete abutments of a non-functional rough fish barrier upstream of the weir. The Shoshone-Bannock Tribes of Fort Hall have also requested the issuance of a 20-year special use permit for continued operation and maintenance of the Pettit Lake Creek Weir. The current weir operates under a 5-year special use permit that expired on December 31, 2019. The Bonneville Power Administration will fund the construction of the weir. Why is this project proposed? The new design will resolve several issues that the existing weir currently has. The design of the existing weir was based on a 1994 feasibility study, which indicated a peak discharge for Pettit 3 Notice of Proposed Action Lake Creek of 57 cubic feet per second (SBT 1994). However, peak discharges have routinely exceeded 100 cubic feet per second, making the weir inadequate. The weir routinely experiences debris accumulation, overtopping, and backwater flooding. These issues make weir operation difficult and hazardous for operators during spring trapping, increase the potential for fish mortality, and prevent collection of accurate and precise data. Figure 1: Location of Pettit Lake Creek weir Location Pettit Lake Creek Weir is located on Pettit Lake Creek approximately 0.2 miles downstream of Pettit Lake near the headwaters of the Salmon River. The creek flows from Pettit Lake for approximately 1.2 miles to its confluence with Alturas Lake Creek which then drains into the Salmon River approximately 20 miles upstream of Stanley, Idaho (Figure 1). Project Design As previously discussed, the plan is to construct the new weir in the same general location as the existing weir. The new design accommodates peak flow discharges and incorporates the 4 Notice of Proposed Action required weir specifications of multiple agencies. The new structure will be larger than the current weir and include a new sill, new abutments, a parking area adjacent to the creek, and an access trail from the parking area to the weir (Figure 2). Visual considerations like paint color, architectural design of the structure, and screening are being considered and incorporated to help ensure compliance with Public Law 92-400 and to mitigate impacts to the recreating public. The project has a total area of ground disturbance of approximately 0.5 acres including a 300- foot section of Pettit Lake Creek. Figure 2- Weir access and staging area Project Access and Staging Area The Shoshone-Bannock Tribes of Fort Hall are also considering improving the current parking area and creating an access trail that will aid in operation and maintenance of the weir. The parking area will be gravel and sit in the same general location that operators have used in the past. Weir operators will park a truck and tagging trailer in the parking area and the access trail will connect the parking area to the weir’s right-bank abutment. The trail would allow for foot travel and occasional ATV access to the work area and weir. The staging area for contractor equipment will be located South of the weir on previously disturbed ground (Figure 2), alongside Forest Road 362 which is approximately 350 feet South of the weir location and 300 feet from Pettit Lake Creek (at its closest point). Construction equipment and temporary storage of materials and supplies will be the main use of the staging area. The staging area is not visible from Forest Roads 208, 361, 362, or 365, though it is possible that large vehicles or materials placed there may be partially visible from Road 208, 5 Notice of Proposed Action depending on their height. Weir Design The proposed design would include a bridge weir within the creek and an adult trap with a holding box on the left bank (Figure 3), in anticipation of the sampling needs required for increased Snake River Sockeye spawning returns, resulting from current and future actions. Figure 3: Proposed weir design Project Construction Sill (foundation of weir) The weir sill, per National Marine Fisheries Service criteria, will be a uniform concrete surface. The uniform sill provides a solid surface against which the weir panels can seal to prevent fish from going under the trap. The sill will consist of a precast, concrete, box-like section with a lid. It will be filled with native substrate and secured to the channel section. This design’s benefit is that the sections and lid can be precast and delivered to the site for easy installation. The concrete does not need any field cure time. The precast units have a connection system that will allow for ease in securing the lid to the vault. The vault will have weep holes to prevent buoyancy forces from misaligning the structure over time. To install the sill, contractors will trench the channel and compact the base as much as possible. They will then place the channel sections within the excavated area and place the excavation soil back into the box. The lid will then be set on top of the channel sections and secured in place. The structural steel members of the bridge weir will be anchored to the concrete lid (see Figure 4). 6 Notice of Proposed Action Figure 4: Typical sill construction (example from Redfish Lake Creek weir installation) If, during construction, the gravel bed proves unsuitable for the precast concrete sill construction method, a cast-in-place foundation system will be utilized. The system will be like the precast design but without a full box foundation. Upstream and downstream cutoff walls will be excavated and poured to the required depth and back filled with engineered fill.