PUBLIC NOTICE Corps File No: NWO-2004-10258-WEH Project: Nebraska Highway 12 (N-12) Niobrara East and West US Army Corps Project of Engineers Applicant: Nebraska Department of Transportation Omaha District Waterways: Missouri River, Ponca Creek, Harry Miller Creek, Medicine Creek, Bazile Creek, intermittent waterways (primarily tributaries to the aforementioned surface waters) Release Date: January 3, 2020 February 17, 2020 Comments Due: REPLY TO: Rebecca Latka, N-12 EIS Project Manager U. S. Army Corps of Engineers Omaha District 1616 Capitol Avenue 45-DAY NOTICE Omaha, Nebraska 68102 Phone: (402) 995-2681 E-mail: [email protected] https://www.nwo.usace.army.mil/Missions/Regulatory-Program/Nebraska/EIS-Highway-12/ JOINT PUBLIC NOTICE CLEAN WATER ACT SECTION 404 PERMIT APPLICATION AND AVAILABILITY OF THE SUPPLEMENTAL DRAFT ENVIRONMENTAL IMPACT STATEMENT FOR NEBRASKA DEPARTMENT OF TRANSPORTATION’S NEBRASKA HIGHWAY 12 NIOBRARA EAST AND WEST PROJECT JOINT PUBLIC NOTICE: This public notice is issued jointly by the U.S. Army Corps of Engineers (USACE), Omaha District, and the Nebraska Department of Environment and Energy (NDEE). The NDEE will review the proposed project (N-12) for state certification in accordance with the provisions of Section 401 of the Clean Water Act (CWA). The NDEE hereby incorporates this public notice as its own public notice and procedures by reference thereto. AUTHORITY: Section 404 of the CWA (33 USC 1344) APPLICANT: Mr. Kevin Domogalla, Nebraska Department of Transportation (NDOT), District 3 Engineer, 408 North 13th Street, Norfolk, Nebraska 68702 Page 1 of 8 SUPPLEMENTAL DRAFT ENVIRONMENTAL IMPACT STATEMENT: The USACE has prepared a Supplemental Draft Environmental Impact Statement (SDEIS) to analyze the direct, indirect and cumulative effects of a proposed Nebraska state highway project, Nebraska Highway 12 Niobrara East and West Project (Project), by the NDOT. NDOT proposes to rehabilitate two segments of N- 12 east and west of Niobrara, between Verdel and Spur 54-D in Knox County, Nebraska. The SDEIS describes the Project by the NDOT; a road rehabilitation of N-12 which incorporates an elevation increase to the 100-year flood elevation plus 3 feet. Alternatives to this proposal have also been reviewed, with all alternatives within the existing N-12 corridor, and are described in the SDEIS. The purpose of the Project is to improve the safety and reliability of the roadway and meet current NDOT design standards. PROJECT LOCATION: The Project is located in Knox County, in northeastern Nebraska near the village of Niobrara. Niobrara West or Segment 1 is approximately 6.4 miles long and extends from just east of Verdel, Nebraska east to 2 miles west of the N-12 Niobrara River Bridge. Niobrara East or Segment 2 is approximately 6 miles long and extends from just east of Spruce Avenue in Niobrara east to approximately 1 mile east of Spur 54D. PROJECT DESCRIPTION: All alternatives use a similar vertical profile clear of the anticipated wave action based on the current 100-year flood elevations, without consideration for future siltation for each alignment. Consistent with standard NDOT practice, a 6-foot buffer past the limits of construction was also included when determining wetland impacts. It is proposed that traffic and access to existing properties will be maintained with temporary pavement and by phasing construction at key locations where access is not available along other routes. NDOT’s Applied-For Project, S-3 Minimized: Alternative S-3 Minimized involves raising the existing N- 12 roadway on a parallel alignment for both the west and east segments to an elevation approximately 3 feet above the projected water surface elevation of the Missouri River during a 100-year flood event. The 3 additional feet compensates for potential wave action (assumed to be 3.0 feet). The total roadway elevation increase would be approximately 4 to 9 feet higher than the existing N-12, depending on location. In addition, the roadway would be widened to have 12-foot driving lanes, 2-foot paved plus 6- foot turf shoulders (8 total feet), 30-foot lateral obstacle clearance, and sloping embankments. Curvature and ingress and egress considerations for county roads and private access would be modified to satisfy current NDOT design standards and to facilitate an adequate level of service for east-west traffic. A 6:1 maximum slope would be used within the clear zone, with a 3:1 maximum slope used to tie into existing ground. Riverside slopes would be armored with riprap to 1 foot above anticipated wave action. The west segment would be 6.4 miles long; the east segment would be 6.0 miles long; and proposed elevation of the N-14 segment would be 0.7 mile long. Traffic is proposed to be maintained on a two-lane temporary roadway offset to the north through the construction zone, consisting of two 12-foot driving lanes, a 6-foot shoulder adjacent to the new roadway, and a 4-foot shoulder within the future ditch of the new roadway. Existing intersections with county roads and private crossings would remain open during construction to the greatest extent possible. Construction would likely occur in phases consisting of different sections within the west and east segments. It is anticipated that the work would generally progress linearly, with bridge construction occurring in advance of, and during, roadway and culvert construction. Each phase would begin with adding necessary embankment, culvert extensions, and pavement to provide for temporary maintenance of traffic. Once traffic is shifted to the temporary pavement, additional roadway embankment and the Page 2 of 8 proposed improvements would be constructed. Because traffic is proposed to be maintained to the north, temporary crossovers would be needed to use existing bridges where proposed bridges would be located to the south of the proposed alignment, such as at Bazile Creek. PROPOSED HIGHWAY N-1 2 - Sl For more information on the applied-for Project and its alternatives, see Chapters 2.0 and 5.0 of the SDEIS. PROJECT PURPOSE: NDOT’s stated project purpose is to maximize utilization of existing transportation infrastructure by rehabilitating the existing N-12 to improve the safety and reliability of the roadway, as well as to meet current NDOT arterial design standards for a major arterial-intermediate highway, between approximately Verdel, NE and Spur 54D. Rehabilitation of the existing road would preserve the existing transportation asset and its right-of-way, provide a safer and more efficient roadway that accommodates the need for local and regional mobility of the travelling public (including commercial traffic). NDOT indicated the project is needed due to ongoing risk of flooding, unreliable operations, and interruptions to regional connectivity. The existing N-12 roadway does not meet current arterial roadway design standards for a major arterial-intermediate highway. Continuing the current practice of maintenance fixes would not address the overall issue of a sub-standard roadway. For supporting information, see Chapter 1.0 of the SDEIS. The basic project purpose, as defined by the USACE, is road rehabilitation. The overall project purpose, as defined by the USACE, is to rehabilitate the existing roadway to maximize utilization of the existing transportation infrastructure and right-of-way, improve the safety and reliability, and bring the roadway up to current NDOT design standards for a major arterial highway between Verdel and the Spur 54D. This project purpose would be used to evaluate the full range of alternatives under Section 404(b)(1) guidelines and NEPA (see Chapter 2.0, SDEIS). SPECIAL AQUATIC SITES: The total acreage of permanent wetland and stream impacts anticipated from Alternative S3 Minimized is 90.06 acres of wetlands in the following types (PEMA, PEMC, PEMF, PFOA, PSSA and PUBG), and 1,206 linear feet (0.61 acre) of stream channel impacts in the following types (perennial, intermittent, ephemeral). A summary of this information for the applied-for alternative, and a breakdown of wetland type by Cowardin classification is provided in Chapter 5.0 of the SDEIS. See Appendix E of the SDEIS for a visual representation of the impacts. AVOIDANCE, MINIMIZATION, AND MITIGATION: NDOT applied several strategies to avoid and/or minimize aquatic resource impacts to Alternative S-3, in order to develop Alternative S-3 Minimized. NDOT will not compromise safety or disregard arterial design standards for a major arterial- Page 3 of 8 intermediate highway in order to consider avoidance measures through the extensive use of guardrail or placement of bridges in areas that do not qualify as bridge size structures. Because of the interrelated nature of roadway design criteria, the proposed avoidance and minimization strategies needed to be applied simultaneously to determine the feasibility and adjustments needed to reduce impacts while still satisfying the NDOT designated minimum design criteria. For this reason, individual gains for each strategy as a standalone modification are not available nor practicable to determine. • Adjusting top of culvert elevations to be at the 100-year flood elevation plus 3 feet of wave action • Adjusting the roadway profile to remain above the 100-year flood elevation plus 3 feet of wave action while allowing the proposed profile to be lower than the existing profile • Shifting the horizontal alignment to avoid wetland impacts • Eliminating ditches located in areas where wetlands would be impacted • Maintaining existing traffic on the south side to allow using existing bridges as temporary bridges during project construction. • Utilize a temporary slope during construction of the permanent lanes to allow using significant portions of the existing road as the temporary road during project construction. During final design, potential further minimization of wetland impacts for the Applied-for Project would be evaluated, and design alterations would be made to minimize wetland impacts where practical. COMPENSATORY MITIGATION: NDOT evaluated mitigating project wetland impacts at wetland mitigation banks within a service area encompassing the sites impacted.