SUBJECT: The U.S. Army Corps of Engineers, Albuquerque District, (Corps) is evaluating a permit application from the City of Colorado Springs Stormwater Enterprise to construct the Cottonwood Creek Stabilization from Academy to Union project, which would result in impacts to approximately 3.08 acres of waters of the United States (WOTUS), including 0.29 acre of wetlands adjacent to Cottonwood Creek and 3,415 linear feet of stream. 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 WOTUS.
APPLICANT: City of Colorado Springs Stormwater Enterprise
Adam Copper
30 South Nevada Avenue, Suite 401
Colorado Springs, Colorado 80901
Adam.Copper@coloradosprings.gov
AGENT: CORVUS Environmental Consulting LLC
Korby Mintken
6419 South Marion Place
Centennial, Colorado 80121
kmintken@corvusenv.com
LOCATION: The proposed project site is located in the city of Colorado Springs, between North Academy Boulevard and North Union Boulevard, within and adjacent to Cottonwood Creek, at approximately latitude 38.9299°, longitude -104.7844°, El Paso County, Colorado.
PROJECT DESCRIPTION: The applicant proposes to stabilize the channel by eliminating vertical banks to address existing degradation and reconnect the floodplain. The proposed work will begin about 850 feet upstream of Academy Boulevard and continue upstream along Cottonwood Creek for about 3,415 feet. The proposed work would tie into existing drop structures upstream, downstream, and within the project reach.
The project involves the placement of 19,323 cubic yards of clean onsite fill, soil, and concrete-filled riprap and boulders below the OHWM and into wetlands to rehabilitate existing drop structures, re-grade the channel to a 3:1 or less than slope, install cutoff walls upstream of drop structures, raise the channel elevation within steep canyon sections, and rehabilitate adjacent stormwater outfalls. The addition of fully grouted boulder drop structures are proposed to achieve longitudinal channel stability.
Revegetation is proposed to establish habitat and support the regraded banks. Disturbed and existing bare areas would be revegetated with live herbaceous and woody species, as well as distributing native wetland and riparian/upland seed mixes throughout.
Based on the available information, the overall project purpose is to stabilize a degrading stream channel, increase floodplain connectivity, and reduce the potential for future scour. The applicant believes there is a need to discharge dredge/fill material into Cottonwood Creek and its adjacent wetlands to address degradation along Cottonwood Creek, stabilize the channel, reduce future maintenance needs, and protect current infrastructure along the corridor. The attached drawings provide additional project details.
PROPOSED MITIGATION: Mitigation is an important part of the Corps’ permitting process. Mitigation is sequential and includes avoidance, minimization, and compensation for unavoidable adverse impacts to aquatic resources. A detailed mitigation plan is not required for issuance of a public notice, but all three aspects of mitigation must be adequately addressed prior to any Corps’ permit decision. Currently, the applicant is proposing the following mitigation:
The applicant stated that the proposed work would result in 3.08 acres of unavoidable impacts to Cottonwood Creek and its adjacent wetlands. To minimize impacts to WOTUS, the applicant stated that the project was limited to areas where treatment would be most effective while still achieving the project’s purpose and need. To minimize adverse effects to wetlands outside of the project area, the project would implement Best Management Practices (BMPs) during construction to minimize adverse effects on water quality and to minimize excessive sediment transport. BMPs, including but not limited to, sediment control logs, construction limits fencing, vehicle-tracking pads at site entrances/exits, and temporary rock check dams, would be used to reduce impacts outside of the project areas.
To compensate for the unavoidable 0.29 acre of wetland impact, the applicant proposes the creation/replacement of 0.45 acre of wetland. A functional assessment using Colorado Department of Transportation’s Functional Assessment of Colorado Wetlands (FACWet) was completed, resulting in a functional score of 0.66, which identifies the on-site wetlands as “functionally impaired”. The applicant proposes to increase the function of the wetlands to a score of approximately 0.75, to classify the wetland as “functioning”.
The applicant submitted a Colorado Stream Quantification Tool assessment that reflects a net gain of 140.7 Functional Feet across all reaches. Therefore, stream mitigation is not proposed.
The Corps has not yet determined the adequacy of the applicant’s proposed compensatory mitigation.
OTHER AUTHORIZATIONS:
State or Tribe Water Quality Certification: Under Section 401 of the Clean Water Act, the Corps cannot issue a permit to conduct any activity that may result in a discharge into WOTUS unless a Section 401 water quality certification (WQC) is granted, verifying compliance with water quality requirements, or WQC is waived. The Colorado Department of Public Health and Environment is the certifying authority responsible for making WQC decisions.
ADDITIONAL INFORMATION:
Environmental Setting: There are approximately 0.72 acres of wetlands that are WOTUS within the proposed project area and there are approximately 4.83 acres (4,500 linear feet) of intermittent stream that are WOTUS within the proposed project area. The site consists of upland, riparian, and aquatic (e.g., wetlands and waters) habitats. Cottonwood Creek flows to the west through the project area and is a tributary of Monument Creek. Mature woody vegetation (e.g., trees and shrubs) is common throughout the corridor, with a dense herbaceous understory. Wetlands in the project area are classified as palustrine emergent (PEM) and palustrine scrub shrub (PSS). The project area is bound by residential properties that line the north and south sides of the creek, and Cottonwood Creek Trail runs east/west along the south side of the channel (between the creek and residential homes).
Alternatives: Alternatives to the proposed project are analyzed to identify the least environmentally damaging, practicable alternative that meets the applicant’s project purpose and need. Practicability is based on cost, logistics, and technology. All project alternatives, including those which may be less damaging to the aquatic environment, will be considered. The applicant has provided information concerning project alternatives. Alternatives considered by the applicant include:
Alternative 1 – No Action alternative. The applicant would not undertake any activities to stabilize the Cottonwood Creek corridor and a Clean Water Act Section 404 Individual Permit would not be required.
Alternative 2 – Non-aquatic/No Federal Action Alternative. General activities to support riparian health would be implemented; however, the Applicant would not undertake any activities would require a Clean Water Act Section 404 Individual Permit.
Alternative 3 –Re-grading Extension Upstream to Union Boulevard. This alternative would include re-grading the channel to match the upstream and downstream elevations more seamlessly. Existing structures would remain in place and failing/undermined structures would be rehabilitated. This alternative would increase the length of channel being re-graded by ~800 linear feet, which could potentially reduce the number of additional drop structures needed. This alternative would impact a portion of Cottonwood Creek that is not currently experiencing the extreme degradation and scour that the project area contains and would involve permanent impact to healthy wetland and riparian habitats.
Alternative 4 – Buried Drop Structure and Upstream Re-grading. This alternative proposes burying existing grouted boulder drop structures near the downstream end of the project area to help control vertical stability of the channel. Re-grading would be completed upstream of this structure to achieve lateral stability and would tie into existing in-stream structures. Existing compromised in-stream structures would be rehabilitated to return their function. This alternative would create opportunity for additional floodplain bench creation providing area for wetland and riparian habitats and additional area for floodplain inundation.
Alternative 5 – Vertical and Horizontal Channel Stabilization and Floodplain Reconnection (proposed project, described above).
Other alternatives may develop during the review process for this permit application.
HISTORIC PROPERTIES: The Corps consulted district files and records, the latest version of the National Register of Historic Places (NRHP), and state records of NRHP-eligible and potentially eligible historic properties to determine if there are any historic properties that may be affected by the proposed undertaking. There are no documented cultural resources or historic properties identified within or in the immediate vicinity of the proposed project area. The proposed project permit area is largely comprised of an intermittent stream that has been extensively modified by previous work and has little likelihood of impinging upon a historic property even if such properties were to be present. Based on this initial information, the Corps has made a preliminary determination that the proposed project will not likely affect any historic properties that meet the criteria for inclusion in the NRHP.
ENDANGERED SPECIES: The Corps has reviewed the U.S. Fish and Wildlife Service's latest published version of federally listed endangered and threatened species located in El Paso County, Colorado to determine if any listed species or their critical habitat may occur in the proposed project area. The Corps has made a preliminary determination that the proposed project will not affect any federally listed endangered or threatened species or their critical habitat that are protected by the Endangered Species Act. The Corps will initiate consultation with the U.S.
Fish and Wildlife Service pursuant to Section 7 of the Endangered Species Act, as appropriate.
FLOODPLAIN MANAGEMENT: The applicant stated that they intend to apply for a Conditional Letter of Map Revision (CLOMR). The Corps is sending a copy of this public notice to the local floodplain administrator. In accordance with 44 CFR part 60 (Flood Plain Management Regulations Criteria for Land Management and Use), the floodplain administrators of participating communities are required to review all proposed development to determine if a floodplain development permit is required and maintain records of such 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 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.
CLOSE OF COMMENT PERIOD: All comments pertaining to this Public Notice must reach this office on or before June 3, 2024, which is the close of the comment period. Extensions of the comment period may be granted for valid reasons provided a written request is received by the limiting date. If no comments are received by that date, it will be considered that there are no objections. 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. Comments and requests for additional information should be submitted to:
U.S. Army Corps of Engineers, Albuquerque District
Attn: Kerrianne Zdimal, Project Manager
Southern Colorado Branch, Durango Office
1970 East 3rd Avenue, Suite 109
Durango, Colorado 81301-5025
Phone: (970) 259-1764 X 1
E-mail: Kerrianne.L.Zdimal-Quarles@usace.army.mil
Please note that names and addresses of those who submit comments in response to this public notice may be made publicly available through the Freedom of Information Act.