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Item 3A - WET2023-00010
M E M O R A N D U M TO: Planning Board FROM: Edward Stafford, P.E., PTOE, Senior Civil Engineering Manager DATE: August 8, 2023 CALL UP ITEM: Standard Wetland Permit (WET2023-00010) 19th Street and Fourmile Canyon Creek Bridge Replacement Key Dates Wetland permit approved by staff: 8/8/2023 The decision may be called up by Planning Board on or before: 8/22/2023 There is one Planning Board meeting within the 14 day call up period on: 8/22/2023 Project Description The city of Boulder Public Works Transportation Department is constructing a new bridge at 19th Street and Fourmile Canyon Creek (see Figure 1 in the attached report). The existing bridge is made of timber and frequently overtops 19th street during flood events. The new bridge will increase conveyance capacity of floodwaters, provide an underpass for the multiuse path, and improve safety on 19th Street during flooding events. The project area contains regulatory wetlands protected under the City’s wetland ordinance. This application is for the removal of existing wetland vegetation, replacement, and enhancement of wetland areas and for monitoring and mitigation of the wetland areas. Wetland Review Criteria for Standard Wetland Permits •Hydrology: the main source of hydrology for this project is ground and stream water. This source hydrology will not be diminished or reduced as a result of this project. •Minimization: Channel improvement projects pose a unique challenge in terms of minimizing their impact. The site is constrained by various factors, including private property ownership, right of way, school property, minor arterials, and existing easements. These constraints make it particularly challenging to reduce the project's impact. However, the final wetland and riparian habitats will provide increased species and structural diversity as well as an increase in wetland size. •Restoration of Temporary Impacts: consists of native vegetation and seed and restoring grades to pre-construction topography. Item 3A - WET2023-00010 • Best Management Practices: will be utilized during construction phase and include sediment and erosion control devices to prevent erosion of streambanks and sediment from entering the water way. • Protection of Species: there are no threatened or endangered species in the project area. There are no Preble’s jumping mouse or Ute Ladie’s Orchid habitat present on the site. • Mitigation Plan: the restoration area will be monitored for five years or until the wetland permit success criteria are fully met. The proposed project will have the following impacts to city regulated wetlands: Permanent (acre) Temporary (acre) Wetland 0.151 0.015 Inner Buffer 0.602 0.023 Outer Buffer 0.331 0.245 Associated Floodplain Development Permits A separate floodplain development permit has been submitted for this project and is being reviewed. That floodplain permit will go through public process when it is approved by staff. Questions about the project should be directed to: Edward Stafford, P.E., PTOE Senior Civil Engineering Manager 303-441-4276 StaffordE@bouldercolorado.gov Attachments: A. Wetland Permit Application B. Wetland Permit Report Item 3A - WET2023-00010 Planning & Development Services | 1739 Broadway, 3rd Floor P.O. Box 791 Boulder, CO 80306 303-441-1880 boulderplandevelop.net Page 1 of 4Updated June 2020 WET2020- Wetland Permit Application Wetland permits are required for development that impacts regulatory wetland and buffer zone areas and is required by Section 9-3-9 (see Table 3-1 for required permit type and exemptions) of the Boulder Revised Code. Incomplete applications will not be accepted. Please fill out every section of this form. REQUIRED MATERIALS FOR ALL PERMITS Site Plan (please show the wetland and buffer zone boundaries) At least two photographs of current conditions Construction drawings (as applicable) TO SUBMIT YOUR WETLAND PERMIT APPLICATION Save your application and supplemental files as PDFs Name your materials according to the File Naming Convention in the Electronic Submittal Guide Submit application and files to PDSskipatrip@bouldercolorado.gov CONTACT INFORMATION Applicant Contact Information Name Phone#Email Address Address City State Zip Property Owner Contact Information Same as Applicant Name Phone#Email Address Address City State Zip PERMIT Date: Item 3A - WET2023-00010 Planning & Development Services | 1739 Broadway, 3rd Floor P.O. Box 791 Boulder, CO 80306 303-441-1880 boulderplandevelop.net Page 2 of 4 Updated June 2020 PROJECT INFORMATION Permit Type (please check one) Standard Boundary Determination Conditional Functional Evaluation Project Address: Project Description: please include the who, what, where, when and why in your project description (please also describe if this project is part of a larger project) PROJECT IMPACTS Impact Area (permanent & temporary) Total Impacted Area (square feet) Required Restoration Ratio (area restored to area disturbed) Wetland 2:1 Inner & Outer Buffer Zone 1:1 BEST MANAGEMENT PRACTICES Describe how you will keep sediment or erosion from entering the creek. HYDROLOGY Check all that apply: Current Water Source Groundwater Stream water Rainwater Other: Future Water Source Groundwater Stream water Rainwater Other: Will your project negatively impact site hydrology? Yes No If yes, please describe: Stream water Item 3A - WET2023-00010 Planning & Development Services | 1739 Broadway, 3rd Floor P.O. Box 791 Boulder, CO 80306 303-441-1880 boulderplandevelop.net Page 3 of 4 Updated June 2020 MINIMIZATION Describe the steps taken to ensure that your project is causing the least amount of wetland disturbance. RESTORATION OF TEMPORARY IMPACTS I will be utilizing native wetland seed mix for restoration. Yes No If no, please explain: Will you be restoring at the project location? Yes No If no, please describe where your restoration will occur: OTHER ITEMS TO CONSIDER Does your project include any of the following? Check all that apply: Bank Stabilization Native plants/landscaping are preferred over rip rap or hardened structures (as feasible). Vegetation Removal For noxious weed infestation or native habitat restoration only (applies to inner buffer). New Steps/Pathway Only allowed in buffer zones, one per property, and 4-feet wide maximum. Sediment Removal Shall not alter flood capacity. Vegetated channel bottoms shall be restored. Fill Identify the source of any fill, and the location where any fill will be placed If you checked any of the above, please describe: None of these apply to my project Item 3A - WET2023-00010 Planning & Development Services | 1739 Broadway, 3rd Floor P.O. Box 791 Boulder, CO 80306 303-441-1880 boulderplandevelop.net Page 4 of 4 Updated June 2020 For Standard Review Applications Only PROTECTION OF SPECIES Check one and attach to application: Army Corps of Engineers Nationwide Permit Army Corps of Engineers 404 Permit AND US Fish and Wildlife Threatened & Endangered Species Permit MITIGATION PLAN Please provide a mitigation plan that addresses the following items in the order listed below. 1. Statement that mitigation plan was prepared by qualified wetland biologist 2. Existing site evaluation a. Type and value of existing wetlands b. Total area impacted (use table above) c. Total area to be mitigated (use ratios in table above) d. Construction start/end date 3. Mitigation Site a. Location b. Who owns the mitigation site (do you have their approval?) c. Description of mitigation (i.e. is the site suitable for wetlands?) d. Hydrology description i. where will the water come from to establish the wetland? ii. Who owns the water? Do you have their consent? e. Mitigation start/end date f. Probability of success of mitigation measures 4. Mitigation Site Maintenance a. Description of maintenance activities: weed control, litter removal, irrigation, water control structures, vegetation maintenance (replanting), culvert clearing b. When will maintenance start? c. Who will perform maintenance? d. How often will maintenance be performed? e. When will maintenance end? 5. Mitigation Site Monitoring a. Monitoring criteria: how will you know the site is successful? 80% revegetated, no noxious weeds b. When will monitoring start? c. Who will perform the monitoring? d. When will monitoring end? Item 3A - WET2023-00010 Denver • Durango • Hotchkiss • Idaho www.eroresources.com Consultants in Natural Resources and the Environment City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado Prepared for— City of Boulder 1777 Broadway Boulder, Colorado 80302 and Mile High Flood District 2480 West 26th Avenue, Suite 156-B Denver, Colorado 80211 Prepared by— ERO Resources Corporation 1842 Clarkson Street Denver, Colorado 80218 (303) 830-1188 ERO Project #10675 March 19, 2023 Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 i ERO Resources Corporation Contents Introduction .......................................................................................................................... 1 Location ................................................................................................................................. 1 Existing Conditions ................................................................................................................. 4 Streams, Wetlands, and Water Body Protection...................................................................... 4 Threatened, Endangered, and Candidate Species .................................................................... 7 Public Need and Alternatives Analysis .................................................................................... 8 Description of Activities ......................................................................................................... 9 Realignment and Reshaping of a Channel ....................................................................................... 9 Grade-Control Structures ............................................................................................................... 12 Bank Stabilization ........................................................................................................................... 12 Other Project Elements .................................................................................................................. 12 Description of Impacts ......................................................................................................... 12 Vegetation Removal ....................................................................................................................... 13 Extent of Permanent Adverse Effects ............................................................................................ 14 Cumulative Effects ......................................................................................................................... 14 Uniqueness or Scarcity of Wetlands .............................................................................................. 14 Avoidance and Minimization of Wetland Impacts ................................................................. 15 Construction Methods and Best Management Practices .............................................................. 15 Wetland Mitigation .............................................................................................................. 15 Source of Water for Wetland Mitigation and Site Hydrology ................................................. 16 Planting Plan .................................................................................................................................. 16 Planting Phases .............................................................................................................................. 19 Wetland Maintenance and Monitoring ................................................................................. 19 References ........................................................................................................................... 20 Tables Table 1. Federally threatened, endangered, and candidate species identified on the IPaC resource list for the project area. .............................................................................................. 7 Table 2. Summary of permanent impacts on City-regulated wetlands. ........................................ 13 Table 3. Summary of temporary impacts on City-regulated wetlands. ......................................... 13 Table 4. Trees to be removed and rationale. ................................................................................. 14 Table 5. Proposed planting location and acreage. ......................................................................... 16 Table 6. Native trees and shrubs. .................................................................................................. 17 Table 7. Native submergent seed mix (Zone 1). ............................................................................ 17 Table 8. Native riparian emergent seed mix (Zone 2). .................................................................. 18 Table 9. Riparian floodplain seed mix (Zone 3). ............................................................................. 18 Table 10. Upland/Xeric seed mix (Zone 4). .................................................................................... 18 Table 11. Wetland and riparian plugs. ........................................................................................... 19 Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 ii ERO Resources Corporation Figures Figure 1. Vicinity Map ...................................................................................................................... 2 Figure 2. Existing Conditions ............................................................................................................ 3 Figure 3. City of Boulder High Functioning Wetlands and Wetland Buffers .................................... 6 Figure 4. Proposed Impacts on High Functioning Wetlands .......................................................... 10 Figure 5. Proposed Impacts on Wetland Buffers ........................................................................... 11 Appendices Appendix A Photo Log Appendix B Construction Design Plans Item 3A - WET2023-00010 ERO Project #10675 1 ERO Resources Corporation City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado March 19, 2023 Introduction The city of Boulder (City), in partnership with Mile High Flood District (MHFD), is proposing stream improvement activities along a segment of Fourmile Canyon Creek (FMCC) immediately upstream and downstream of 19th Street in Boulder, Colorado (Figure 1; project area). On behalf of the City and MHFD, ERO Resources Corporation (ERO) submits this document as a portion of the application for a City Standard Wetland Permit as described in Chapter 9-3-9 of the City’s Streams, Wetlands and Water Body Protection Ordinance (City’s wetland ordinance) for the proposed project. Within the project area, the current channel alignment of FMCC as it approaches the 19th Street bridge has eroded and become undercut in areas, affecting conveyance through the project reach. The reduced conveyance has caused water to frequently overtop 19th Street, which has created a public safety hazard. The proposed project would replace the existing 19th Street timber bridge and reshape and realign the channel to improve flow and reduce flooding throughout the project reach while also creating a grade separated bike and pedestrian underpass under 19th Street to create safer travel along the FMCC path. The proposed project would improve stream function and conveyance through the reach by reestablishing the historic low-flow channel. The proposed project would improve the safety of the trail by reducing flooding events and by creating an underpass crossing of 19th Street and improve emergency access to Tamarack Avenue. FMCC is 6 to 10 feet wide in the project area and is mapped as a City-regulated wetland. Location The project area is in Section 18, Township 1 North, Range 70 West of the 6th Principal Meridian in Boulder County, Colorado (U.S. Geological Survey 2019) (Figure 1). The UTM coordinates of the approximate center of the project area are NAD 83 476721mE, 4433603mN, Zone 13 North. The longitude/latitude of the project area is 105.272928°W/40.052353°N. The elevation of the project area is approximately 5,460 feet above sea level. Photos of the project area are included in Appendix A, and photo points are shown on Figure 2. Item 3A - WET2023-00010 Prepared for: RS&H File: 10675 Figure 1 cob.mxd (WH) May 15, 2023 ± Figure 1 Vicinity Map 19th Street and Four Mile Canyon Creek Portions of this document include intellectual property of ESRI and its licensors and are used herein under license. Copyright © 2020 ESRI and its licensors. All rights reserved. 0 1,000500Feet COLORADO Location Section 18, T1N, R70W; 6th PM UTM NAD 83: Zone 13N; 476750mE, 4433585mN Longitude 105.272584°W, Latitude 40.052186°N USGS Boulder, CO Quadrangle Boulder County, ColoradoPath: P:\10600 Projects\10675 - 19th St and Four Mile Canyon Creek - Boulder\Maps\COB\10675 Figure 1 cob.mxdProject Area Item 3A - WET2023-00010 aaa!. !.!. !. !. Upland Avenue 19th StreetCanada Thistle Houndstongue DP3 DP4 DP1 DP2 Fourmile Canyon Creek (0.077 ac) W6 (0.0017 ac) W7 (0.0013 ac) W5 (0.0006 ac) W1 (0.0004 ac) W3 (0.0004 ac) W2 (0.0002 ac) W4 (0.0008 ac) P3 P2 P1 MBTA Nest Figure 2 Existing Conditions 19th Street and Four Mile Canyon Creek Image Source: City of Boulder 2018 Prepared for: MHFD File: 10675 Figure 2 404.mxd (WH) May 4, 2023 Path: P:\10600 Projects\10675 - 19th St and Four Mile Canyon Creek - Boulder\Maps\404\10675 Figure 2 404.mxd!.Data Point a Photo Point Ordinary High Water Mark (0.077 ac) Wetland (0.006 ac) Noxious Weed Project Area ±0 7035Feet !.MBTA Nest Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 4 ERO Resources Corporation Existing Conditions The Natural Resources Conservation Service (NRCS) has mapped the soils in the project area as Nederland very cobbly sandy loam (U.S. Department of Agriculture, NRCS 2022). Nederland soils occur in alluvial fans and on terraces and typically consist of very cobbly sandy loams. Streams, Wetlands, and Water Body Protection The City’s wetland ordinance was amended and formally adopted in 2009. Streams, wetlands, and various water bodies are protected under the ordinance. The boundaries of streams include the bankfull width of the channel, and the boundaries of water bodies are defined by the presence of a bed and bank or ordinary high water mark. The City defines wetlands based on procedures specified in the U.S. Army Corps of Engineers (Corps) Wetlands Delineation Manual (Corps manual) (Environmental Laboratory 1987). The Corps manual defines wetlands as an area containing three wetland indicators (e.g., hydrophytic vegetation, supportive hydrology, and hydric soils). Additionally, the City has established a 25- or 50-foot protected wetland buffer on either side of City-regulated wetlands, depending on the location and functional rating of the wetlands. The City regulates wetlands and wetland buffers on lands within the City limits and on City-owned land outside the City limits. On July 13, 2020, ERO assessed the project area for potential waters of the U.S., including abutting and adjacent wetlands (site visit). In addition to assessing wetland buffers regulated by the City, ERO delineated wetlands per Corps requirements. Prior to the site visit, ERO reviewed U.S. Geological Survey (USGS) quadrangle topographic maps and aerial photography to identify mapped streams and areas of open water that could indicate wetlands or waters of the U.S (U.S. Geological Survey 2019; Google Earth 2022). The boundaries of identified wetlands and other characteristics of potential waters of the U.S. were mapped using a Trimble Global Positioning System (GPS) unit. Data was differentially corrected using the CompassCom base station. All differential corrections were completed using Trimble Pathfinder Office 5.9 software. GPS data were incorporated using ESRI® ArcGIS Desktop software. Additionally, where appropriate, wetlands were drawn on georectified aerials and then digitized. Delineated wetlands were also classified according to the U.S. Fish and Wildlife Service’s (Service) Cowardin classification system combined with a hydrogeomorphic (HGM) approach (Cowardin et al. 1979; Brinson 1993). The Cowardin classification uses a hierarchical structure of systems, subsystems, and classes to classify both wetlands and deepwater habitats. The HGM approach assesses the chemical, physical, and biological functions of wetlands based on its geomorphic setting, water source, and hydrodynamics. HGM classes found in Colorado are mineral soil flats, organic soil flats, riverine, lacustrine fringe, slope, and depressional. Within the project area, wetlands occur along the channel banks of FMCC. The Cowardin classification for most of the mapped wetlands is palustrine emergent, with smaller areas of palustrine scrub-shrub. The dominant vegetation in the wetlands consists of narrowleaf willow (Salix exigua - facultative Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 5 ERO Resources Corporation wetland [FACW]), reed canarygrass (Phalaris arundinacea - FACW), and American speedwell (Veronica americana - obligate wetland). Waters tributary to navigable waters are considered waters of the U.S. and are subject to the Corps’ jurisdiction. FMCC is shown on the USGS Boulder topographic quadrangle as a perennial stream. FMCC is a tributary to Boulder Creek, and the confluence of these creeks occurs approximately 3.47 miles southeast of the project area. The Corps has previously determined that FMCC is a jurisdictional water of the U.S. Water was flowing in FMCC at the time of the site visit. During the site visit, ERO mapped approximately 0.077 acre of stream channel and 0.006 acre of wetlands in the project area (Figure 2). ERO will be submitting an application to the Corps in April 2023 requesting authorization under the appropriate Section 404 permit. FMCC and its abutting vegetation are regulated under the City’s wetland ordinance. The City also regulates a 50-foot wetland buffer consisting of a 25-foot inner buffer and 25-foot outer buffer on either side of FMCC (Figure 3; Photo 1 and Photo 2). FMCC and its associated buffers are regulated under the City’s wetland ordinance. No ERO delineated wetlands occur outside of the City’s wetland mapping (Figure 3). Item 3A - WET2023-00010 Upland Avenue 19th StreetFigure 3 City of Boulder High Functioning Wetlands and Wetland Buffers 19th Street and Four Mile Canyon Creek Image Source: City of Boulder 2018 Prepared for: RS&H File: 10675 Figure 3 cob.mxd (WH) May 15, 2023 Path: P:\10600 Projects\10675 - 19th St and Four Mile Canyon Creek - Boulder\Maps\COB\10675 Figure 3 cob.mxdHigh Functioning Wetland High Functioning Inner Buffer High Functioning Outer Buffer Project Area ±0 7035Feet Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 7 ERO Resources Corporation Threatened, Endangered, and Candidate Species During the site visit, ERO assessed the project area for habitat for threatened, endangered, and candidate species listed under the Endangered Species Act (ESA) of 1973, as amended (16 United States Code 1531 et seq.). The Service’s Information for Planning and Consultation (IPaC) resource list for the project area identifies several threatened and endangered species that may be affected by the project (Table 1) (U.S. Fish and Wildlife Service 2023). Because the project area falls within survey guidelines for Preble’s meadow jumping mouse (Zapus hudsonius preblei or Preble’s) and Ute ladies’-tresses orchid (Spiranthes diluvialis or ULTO), ERO assessed the project area for suitable habitat for these species. Table 1. Federally threatened, endangered, and candidate species identified on the IPaC resource list for the project area. Common Name Scientific Name Status* Habitat Suitable Habitat Present Mammals Gray wolf Canis lupus E Wolves can thrive in a wide range of habitats; highly adaptable as a species that occurs in temperate forests, mountains, and grasslands; extirpated from Boulder County No habitat Preble’s meadow jumping mouse (Preble’s) Zapus hudsonius preblei T Shrub riparian/wet meadows No habitat Birds Piping plover** Charadrius melodus T Sandy lakeshore beaches and river sandbars No habitat and no depletions Whooping crane** Grus americana E Mudflats around reservoirs and in agricultural areas No habitat and no depletions Fish Greenback cutthroat trout Oncorhynchus clarki stomias T Cool, clear, gravel headwater streams and mountain lakes No habitat Pallid sturgeon** Scaphirhynchus albus E Large, turbid, free-flowing rivers with a strong current and gravel or sandy substrate No habitat and no depletions Insects Monarch butterfly Danaus plexippus C Meadows, forests, riparian areas; breeding habitat requires milkweed (Asclepiadoideae), a summer resident No habitat Plants Ute ladies’-tresses orchid (ULTO) Spiranthes diluvialis T Moist to wet alluvial meadows, floodplains of perennial streams, and around springs and lakes below 7,800 feet in elevation No habitat Western prairie fringed orchid** Platanthera praeclara T Moist to wet prairies and meadows No habitat and no depletions *T = Federally Threatened Species; E = Federally Endangered Species; C = Candidate for Listing as Threatened or Endangered. **Water depletions in the South Platte River may affect the species and/or critical habitat in downstream reaches in other counties or states. Source: Service 2023. There is no likelihood for the proposed project to affect the grey wolf, greenback cutthroat trout, or monarch butterfly because of the lack of suitable habitat in the project area. The piping plover, whooping crane, pallid sturgeon, and western prairie fringed orchid are species that are affected by continued or ongoing water depletions to the Platte River system. Habitat for these species is not present in the project area, and the proposed activities would not result in new depletions to the Platte River system. Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 8 ERO Resources Corporation Suitable habitat for Preble’s is not present in the project area. The project area lacks adequate shrub cover by sandbar willow and other riparian shrubs typically associated with Preble’s habitat. A trapping survey conducted in 1997 approximately 0.14 mile upstream of the project area failed to capture any Preble’s (Service 2014). The nearest known Preble’s population is located along Bear Creek, approximately 3.0 miles southwest of the project area. The project area is separated from Bear Creek by extensive residential and commercial development in the City. Given the above information, it is unlikely the project area supports a population of Preble’s or that the continued existence of Preble’s would be adversely affected by the proposed project. The project area does not contain habitat for ULTO. The herbaceous vegetation in the project area is dominated by nonnative grass and forb species that are not typically associated with ULTO (Service 1992). In addition, the eroding banks have created a disconnect between FMCC and its floodplain and thus does not allow for the development of wet meadow habitat. Public Need and Alternatives Analysis The proposed project is needed to improve safety and accessibility around FMCC within and beyond the project limits. The project replaces the existing 19th Street timber bridge over FMCC and allows widening to accommodate bike lanes and sidewalks in each direction. The project improves emergency access to the neighborhood east of 19th Street by creating a combined emergency and multi-use path access from 19th Street to Tamarack Avenue. Multi-modal improvements include a grade separated bike and pedestrian underpass under 19th Street and access to both sides of 19th Street, which improves access from 22nd Street to Crest View Elementary School. In addition, the project provides flood improvements to convey the 50-year event flows under the 19th Street bridge and proposed channel improvements will reestablish the historical low-flow channel, which has aggraded due to sediment and debris accumulation following the 2013 flood. Strong public need for the proposed project at FMCC is apparent. Three alternatives were evaluated for the proposed project. These alternatives are: 1. No Action. This alternative was rejected because it does not satisfy the project need. Under the no action alternative, the deficient 19th Street timber bridge would not be replaced and conveyance in the channel would remain flashy and erosion would continue to occur. The risk of trail and 19th Street flooding would remain high in the project area. There would also be no protected crossing of 19th Street on the FMCC trail. Under this alternative, public safety would continue to be compromised. 2. Bank Stabilization. Alternative 2 was rejected because it does not meet the project need. This alternative included stabilizing the eroding banks in an attempt to restore their integrity and protect against future storm events. This alternative does not alter the existing channel configuration, which approaches the 19th Street bridge at a sharp angle and does not replace the existing 19th Street bridge. Alternative 2 would likely require repeated maintenance (e.g., additional stabilizations) to maintain the channel banks and reduce erosion. Continued flooding would likely continue due to the angle of approach of FMCC to the 19th Street Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 9 ERO Resources Corporation bridge. This alternative would result in repeated disturbance to the project area over time. Additionally, this alternative does not address the lack of protected crossings for pedestrians using the FMCC trail. This alternative was rejected because it does not provide a stable long- term solution to the bank erosion, conveyance, and flooding problems caused by the current channel configuration in the project reach. 3. Channel Improvements and Underpass (Preferred). Alternative 3 is the preferred alternative because it replaces the existing timber bridge, improves emergency access, improves stream function, increases bank stabilization, reduces sedimentation, reduces maintenance, and improves public safety. In addition, this alternative provides an opportunity to improve the environmental health in the project area. This alternative would likely improve the ecological functions of FMCC and would allow for higher quality wetland habitat to form, especially following completion of mitigation activities. Proposed project activities under this alternative are described in the following sections. Description of Activities To improve public safety and flow conveyance through the project area, the City and MHFD are proposing a combination of channel improvements in addition to the installation of a trail underpass beneath 19th Street with the bridge replacement. The project activities include channel realignment and reshaping, construction of several grade-control structures in the realigned channel, and bank stabilization. A pedestrian underpass would also be constructed beneath 19th Street. The proposed activities would result in impacts on City-regulated wetlands. Impacts on high functioning wetlands are shown on Figure 4 and impacts on regulated inner and outer wetland buffers are shown on Figure 5. Additional details on the proposed activities and associated impacts are provided below, and construction design plans are included in Appendix B. Realignment and Reshaping of a Channel To improve flow conveyance through the project reach and reduce the flood risk to 19th Street and the FMCC trail, the City and MHFD are proposing to realign and reshape approximately 480 linear feet of channel in the project area (Figure 4 and Figure 5). Typical cross-sections of the realigned channel would consist of an approximately 6 to 7-foot-wide low-flow channel with a 2-foot-wide submergent wetland bench on both sides of the low-flow channel and a 5-foot wide riparian emergent bench on both sides of the low-flow channel. The typical bankfull side slope would be graded to a 4:1 slope. The realigned channel would be reshaped so that it matches the downstream channel. To create a seamless match, Type M buried and Type M void-filled riprap would be placed along the reshaped banks. The banks would then be planted with elevation appropriate seed mixes, herbaceous plugs, shrubs, and native trees. The City and MHFD are proposing bank protection and construction of grade-control structures in portions of the realigned stream reach to maintain the desired channel invert, prevent erosion, and provide habitat for aquatic organisms. The grade-control structures and bank protection are described in the following sections. Item 3A - WET2023-00010 Upland Avenue 19th StreetFigure 4 Proposed Impacts on High Functioning Wetlands 19th Street and Four Mile Canyon Creek Image Source: City of Boulder 2018 Prepared for: RS&H File: 10675 Figure 4 cob.mxd (WH) May 15, 2023 Path: P:\10600 Projects\10675 - 19th St and Four Mile Canyon Creek - Boulder\Maps\COB\10675 Figure 4 cob.mxdBoulders Wetland/Riparian Planting Riprap High Functioning Wetland High Functioning Inner Buffer High Functioning Outer Buffer Project Area ±0 7035Feet Proposed Permanent Impact on High Functioning Wetland (0.151 ac) Proposed Temporary Impact on High Functioning Wetland (0.015 ac) Item 3A - WET2023-00010 Upland Avenue 19th StreetFigure 5 Proposed Impacts on Wetland Buffers 19th Street and Four Mile Canyon Creek Image Source: City of Boulder 2018 Prepared for: RS&H File: 10675 Figure 5 cob.mxd (WH) May 15, 2023 Path: P:\10600 Projects\10675 - 19th St and Four Mile Canyon Creek - Boulder\Maps\COB\10675 Figure 5 cob.mxdBoulders/Grouted Riprap Wetland/Riparian Planting Riprap High Functioning Inner Buffer High Functioning Outer Buffer Project Area ±0 7035Feet Proposed Permanent Impact on High Functioning Inner Buffer (0.602 ac) Proposed Permanent Impact on High Functioning Outer Buffer (0.331 ac) Proposed Temporary Impact on High Functioning Inner Buffer (0.023 ac) Proposed Temporary Impact on High Functioning Outer Buffer (0.245 ac) Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 12 ERO Resources Corporation Grade-Control Structures To maintain a 2.4 percent channel invert, prevent erosion and sediment transportation problems, and provide habitat for aquatic organisms, the City and MHFD are proposing to construct several small grade-control structures in the realigned channel (Figure 4 and Figure 5). The City and MHFD are proposing to construct two boulder drop structures with associated cutoff walls. The proposed drop structures would be constructed north of the 19th Street bridge toward the upstream end of the project area. The drop structures would consist of 36-inch-diameter grouted boulders (typical) with 48-inch- diameter feature boulders intermittently placed in a single layer as tightly together as possible to allow proper placement of grout without any gaps (Appendix B). A silting pool would be located on the downstream side of the structure. Type L and Type H void-filled riprap would be placed in the channel upstream of the first structure and Type VL void-filled riprap would be placed in the channel upstream of the second structure to protect the approach to the structure from erosion and to match the elevation of the embedded boulders. Bank Stabilization The City and MHFD are proposing riprap bank protection along approximately 375 linear feet of the realigned channel (Figure 4 and Figure 5). Riprap bank protection would be constructed throughout the project reach both upstream and downstream of the cutoff walls associated with the drop structures. Riprap bank protection would consist of a buried Type VL riprap, buried Type M riprap, and Type M void- filled riprap embedded in the toe and banks of the realigned channel. In addition, soil lifts would be installed at two locations to provide bank stabilization. Other Project Elements Other project-related activities may result in temporary impacts on FMCC and include the construction of the pedestrian trail and underpass beneath 19th Street. These activities include erosion- and sediment-control measures, dewatering activities, and construction access. Description of Impacts The FMCC channel qualifies as a regulated wetland under the City’s wetland ordinance and includes a 50-foot buffer. The proposed project would permanently impact approximately 0.151 acre (6,588 square feet) of City-regulated wetlands, 0.602 acre (26,209 square feet)of inner wetland buffer, and 0.331 acre (14,401 square feet) of outer wetland buffer (Figure 4 and Figure 5). Permanent impacts would result from grading to realigning and reshaping the channel, installing grade-control structures, and installing bank protection along the realigned channel (Table 2). Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 13 ERO Resources Corporation Table 2. Summary of permanent impacts on City-regulated wetlands. Activity Type per Table 3-1 in Boulder Revised Code, 1981 Permanent Impact on Regulated Wetland (acre/square feet) Permanent Impact on Inner Buffer (acre/square feet) Permanent Impact on Outer Buffer (acre/square feet) 27. Stream channel widening, regrading, or reconstruction; new drop structure installation; or sediment removal involving alteration of the existing slope or banks 0.065/2,824 0.337/14,689 0.305/13,267 30. Stream bank or slope stabilization 0.086/3,764 0.265/11,520 0.026/1,134 Total Permanent Impacts per Resource 0.151/6,588 0.602/26,209 0.331/14,401 Total Permanent Project Impacts 1.084/47,198 The proposed project would temporarily impact approximately 0.015 acre (658 square feet) of City- regulated wetlands, 0.023 acre (1,021 square feet) of inner wetland buffer, and 0.245 acre (10,669 square feet) of outer wetland buffer (Table 3). Temporary impacts would result from equipment staging and access during construction. Temporarily impacted areas would be restored to preconstruction conditions (see Wetland Mitigation section). Table 3. Summary of temporary impacts on City-regulated wetlands. Activity Type Temporary Impact on Regulated Wetland (acre/square feet) Temporary Impact on Inner Buffer (acre/square feet) Temporary Impact on Outer Buffer (acre/square feet) Equipment staging and access during construction 0.015/658 0.023/1,021 0.245/10,669 Total Temporary Project Impacts 0.283/12,348 Vegetation Removal The proposed project would result in removal of 44 trees along FMCC (Table 4) and 14 trees would be protected during construction (Appendix B). The project area would be planted with trees and shrubs following construction to replace removed woody vegetation (see Wetland Mitigation section). Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 14 ERO Resources Corporation Table 4. Trees to be removed and rationale. Species Quantity Diameter at Breast Height (inches) Value Rationale Plains cottonwood 6 >8 High Trees may be trimmed to allow for equipment staging, access, and operation during construction. Additionally, some trees would be removed to allow for construction of the realigned channel. Siberian elm 23 >8 Low Honeylocust 1 18 High Honeylocust 1 2 Moderate Green ash 1 4 Low Crabapple 1 16 Moderate Maple 1 10 Good Spruce 4 >6 Good Pine 1 14 Good Fir 1 12 Good Linden 1 10 High Unknown shrub 1 NA Low Unknown tree 2 24 NA Total 44 Extent of Permanent Adverse Effects The proposed permanent impacts on City-regulated wetlands and buffers include grading to realign and reshape the channel and installing grade-control structures and bank stabilization. The proposed activities would permanently modify the configuration of FMCC and its abutting wetlands; however, no permanent adverse effects on City-regulated wetlands and buffers are anticipated from the proposed project. Mitigation measures are incorporated into the channel design plan to improve stream and wetland function in the project area. The City and MHFD are proposing to mitigate permanent impacts on City- regulated wetlands on-site and in place (see Wetland Mitigation section). The proposed project would not expand the existing impervious surface area in the project area, and all disturbed areas would be revegetated with native vegetation following construction. Cumulative Effects The project area is managed as open space and located in a heavily developed portion of the City along the FMCC riparian corridor. The project area is surrounded by dense residential developments. Within the immediate project area, no additional reasonably foreseeable actions are known or anticipated because the project area is primarily in a property managed as open space. It is anticipated that land use in the project area would remain the same in the future. Uniqueness or Scarcity of Wetlands All wetlands in the Boulder Valley are valued, but the mapped wetlands that occur in the project area are not particularly unique or scarce. The wetlands and riparian corridor in the project area contain species found in many of the riparian corridors in the Boulder Valley and Colorado. Sandbar willow, reed canarygrass, and American speedwell-dominated wetlands are abundant in urban settings found along the Front Range (Photo 3). The project would reestablish diverse vegetation cover, improve public Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 15 ERO Resources Corporation safety, and improve the ecological integrity of the project area by improving stream function and increasing the structural and species diversity of wetland vegetation. Avoidance and Minimization of Wetland Impacts Efforts would be made to minimize impacts on the streambed and existing woody vegetation to the maximum extent possible; however, due to the primary purpose of the project (channel improvements), impacts on City-regulated wetlands are unavoidable. Measures that would be implemented during construction to help minimize impacts on vegetation include installing temporary fencing to define construction limits and deterring access into areas that are not to be impacted. In addition to avoiding and minimizing direct impacts, water quality Best Management Practices (BMPs) would be implemented during construction to minimize indirect impacts on the stream channel and adjacent areas. Standard BMPs such as the use of sediment-control logs, construction limits staking and fencing, use of swamp mats for access across existing wetlands, and vehicle tracking control at the site entrance would be implemented. Construction Methods and Best Management Practices BMPs would be implemented during construction, which would help minimize impacts on the stream channel and riparian areas. These BMPs include placing staging areas in previously disturbed areas and installing sediment- and erosion-control devices to minimize surface runoff in disturbed areas. No areas outside of the project area limits would be disturbed. Wetland Mitigation FMCC is considered a high functioning wetland by the City (Land Stewardship Consulting, Inc. 2004). The proposed project would permanently impact approximately 0.151 acre (6,588 square feet) of City- regulated wetlands, 0.602 acre (26,209 square feet)of inner wetland buffer, and 0.331 acre (14,401 square feet) of outer wetland buffer (Table 2; Figure 4 and Figure 5). The proposed project would temporarily impact approximately 0.015 acre (658 square feet) of City- regulated wetlands, 0.023 acre (1,021 square feet) of inner wetland buffer, and 0.245 acre (10,669 square feet) of outer wetland buffer (Table 3; Figure 4 and Figure 5). Following project completion, in- place mitigation will restore 0.10 acre (4,354 square feet) of wetland, 0.209 acre (9,098 square feet) of inner wetland buffer, and 0.008 acre (351 square feet) of outer buffer. As designed, the project includes removal of 44 trees along FMCC (Table 4). The regulatory resources impacted by the proposed project would be restored and enhanced on-site and in place by planting trees and shrubs, native wetland plugs, and a native wetland seed mix in the project area. The proposed project includes realignment and construction of 2-foot-wide submergent zone and 5-foot-wide riparian emergent zone located in benches along both sides of the realigned channel. Additional communities identified in the restoration planting zones include the riparian floodplain and upland/xeric habitats (Table 5). Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 16 ERO Resources Corporation The existing wetlands in the project area are dominated by a mix of native and nonnative species and are limited in size due to the bank erosion along FMCC that has occurred. The proposed planting plan would enhance wetland and riparian habitats in the project area by increasing species and structural diversity throughout the project reach as well as overall size. The proposed project would improve public safety, reduce maintenance issues, and improve aquatic function in the project area. Table 5. Proposed planting location and acreage. Planting Zone Mitigation Acres Zone 1. Submergent 0.03 Zone 2. Riparian Emergent 0.08 Zone 3. Riparian Floodplain 0.11 Zone 4. Upland/Xeric 1.00 Total 1.22 A total of 1.194 acres of permanent impacts on City-regulated wetlands, inner buffer, and outer buffer would be mitigated through restoration activities. Source of Water for Wetland Mitigation and Site Hydrology Groundwater and surface water from FMCC would be the water sources for the project. Mitigation would occur adjacent to vegetated areas where groundwater is sufficient. Planting Plan Appendix B shows the proposed planting plan for the project. As discussed above, the project design includes construction of wetland benches along the realigned channel and revegetation of the existing channel alignment, which would be plugged and filled. Native wetland plugs and a native wetland seed mix would be planted in the proposed wetland benches. The existing channel alignment would be plugged, filled, and reseeded with a native wetland/riparian seed mix. A wetland/riparian seed mix would be planted along the realigned channel banks and all disturbed upland areas in the project area. Trees and shrubs would be planted along the channel banks and along the alignment of the existing channel. The proposed project includes removal of 44 trees with a diameter at breast height of greater than 4 inches along FMCC. Potential tree removal would occur throughout the project area. The removed trees would consist of multiple species including plains cottonwood, green ash, honeylocust, spruce, fir, pine, and Siberian elm. Removed trees would be replaced with a combination of trees, shrubs, and willow stakes. The City and MHFD propose that replacing removed trees with a mixture of trees, shrubs, and willow stakes would be sufficient to mitigate for the overall loss of trees and would create an ecological lift in the project area by increasing the structural and biological diversity of woody vegetation in the project reach. In total, the City and MHFD are proposing to plant up to 31 trees, 230 shrubs, and 116 willow stakes in the project area as shown in Table 6. Table 7 identifies the proposed native wetland seed mix. Table 8, Table 9, and Table 10 identify the riparian seed mixes that would be planted along the channel side slopes, the existing channel alignment, the riparian floodplain, and all disturbed uplands in the project Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 17 ERO Resources Corporation area. Table 11 shows the native wetland and riparian plugs that would be planted in the project area. Landscape design plans are provided in Appendix B. Table 6. Native trees and shrubs. Common Name Scientific Name Quantity Trees Austrian pine Pinus nigra 3 Concolor fir Abies concolor 4 Indian magic crabapple* Malus x Indian magic 5 Kentucky coffeetree Gymnocladus dioicus 3 Plains cottonwood Populus deltoides 5 Sensation box elder* Acer negundo ‘Sensation’ 4 Southwestern white pine Pinus strobiformis 4 Swamp white oak Quercus bicolor 1 Tatarian maple* Acer tataricum 2 Total 31 Shrubs Apache plume Fallugia paradoxa 6 Boulder raspberry Rubus deliciosus 10 Chokecherry Prunus virginiana 24 Dwarf blue rabbitbrush Ericameria nauseosa 24 Golden currant Ribes aureum 38 Red osier/red twig dogwood Cornus sericea 24 Snowberry Symphoricarpos species 20 Threeleaf sumac Rhus trilobata 10 Wax currant Ribes cereum 8 Western sand cherry Prunus besseyi 11 Wild plum Prunus americana 14 Woods’ rose Rosa woodsii 41 Total 230 Stakes Sandbar willow Salix exigua 116 Total 116 *Ornamental species. Table 7. Native submergent seed mix (Zone 1). Common Name and Variety Scientific Name PLS/Pounds per Acre* Alkali sacaton Sporobolus airoides 0.1 Canada wildrye Elymus canadensis 5 Fowl bluegrass Poa palustris 0.3 Prairie cordgrass Spartina pectinata 1.3 Slender wheatgrass Elymus trachycaulus 2.5 Thickspike wheatgrass Elymus lanceolatus 3.5 Western wheatgrass Pascopyrum smithii 3.5 Total 16.2 *Drill seed; double rate if broadcast; PLS = Pure live seed. Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 18 ERO Resources Corporation Table 8. Native riparian emergent seed mix (Zone 2). Common Name and Variety Scientific Name PLS/Pounds per Acre* Alkali sacaton Sporobolus airoides 1 Big bluestem Andropogon gerardii 4 Blanket flower Gaillardia aristata 0.1 Green needlegrass Nassella viridula 6 Indiangrass Sorghastrum nutans 3 Perennial ryegrass Lolium perenne subspecies multiflorum 1.25 Prairie coneflower Ratibida columnifera 0.2 Prairie cordgrass Spartina pectinata 3 Purple prairie clover Dalea purpurea 0.2 Rocky Mountain penstemon Penstemon strictus 0.1 Saltgrass Distichlis spicata 3 Switchgrass Panicum virgatum 7 Western wheatgrass Pascopyrum smithii 6 Total 34.85 *Drill seed; double rate if broadcast; PLS = Pure live seed. Table 9. Riparian floodplain seed mix (Zone 3). Common Name and Variety Scientific Name PLS/Pounds per Acre* Alkali sacaton Sporobolus airoides 2 Blanket flower Gaillardia aristate 0.2 Blue grama Bouteloua gracilis 3 Buffalograss Bouteloua dactyloides 5 Dotted blazing star (Gayfeather) Liatris punctata 0.2 Perennial ryegrass Lolium perenne subspecies multiflorum 1.25 Prairie coneflower Ratibida columnifera 0.2 Purple prairie clover Dalea purpurea 0.2 Rocky Mountain penstemon Penstemon strictus 0.1 Saltgrass Distichlis spicata 3 Sand dropseed Sporobolus cryptandrus 2 Sideoats grama Bouteloua curtipendula 5 Switchgrass Panicum virgatum 2 Tansyleaf tansyaster Machaeranthera tanacetifolia 0.1 Western wheatgrass Pascopyrum smithii 10 Total 34.25 *Drill seed; double rate if broadcast; PLS = Pure live seed. Table 10. Upland/Xeric seed mix (Zone 4). Common Name and Variety Scientific Name PLS/Pounds per Acre* Blue grama Bouteloua gracilis 0.63 Green needlegrass Nassella viridula 1.93 Junegrass Koeleria macrantha 0.15 Little bluestem Schizachyrium scoparium 1.07 Sideoats grama Bouteloua curtipendula 1.82 Slender wheatgrass Elymus trachycaulus 4.38 Switchgrass Panicum virgatum 0.63 Western wheatgrass Pascopyrum smithii 6.34 Total 16.95 *Drill seed; double rate if broadcast; PLS = Pure live seed. Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 19 ERO Resources Corporation Table 11. Wetland and riparian plugs. Common Name and Variety Scientific Name Quantity Meadow sage Salvia pratensis 264 Poverty rush Juncus tenuis 712 Prairie cordgrass Spartina pectinata 145 Switchgrass Panicum virgatum 832 Torrey rush Juncus torreyi 115 Total 2,068 Planting Phases The project area would be planted and seeded with the recommended mixes and plugs listed in Table 6, Table 7, Table 8, Table 9, Table 10, and Table 11. Planting would follow construction in fall 2023 when moisture availability is higher. Trees and shrubs may require supplemental irrigation during the first growing season. Biodegradable erosion-control fabric would be used on the banks to help preserve newly seeded areas. Wetland Maintenance and Monitoring The restoration areas would be monitored for 5 years to ensure the wetland mitigation is successful. Site visits would be conducted during each growing season to determine the success of the project. Trees and shrubs would be counted, and seeded areas would be monitored by recording species cover. The site would be considered successful when at least 80 percent (determined by ocular estimate of herbaceous and shrub foliar cover) of the site is vegetated and at least 50 percent of the dominant species present shall have been planted species or are native species. The presence of noxious weeds would be monitored. Those species shown on the Colorado Noxious Weed Inventory List A shall be 100 percent eradicated. Those species shown on List B shall be no more than 10 percent of the total cover in the project area. If the cover of noxious weeds is greater than 10 percent, weed control would be implemented following the City’s Integrated Pest Management Policy. Dense monoculture patches of noxious weeds would be controlled as soon as practicable. Annual monitoring reports would be submitted to the City by September 30. The monitoring reports would include a discussion of weed colonization, a qualitative description of the mitigation area including establishment of native seed, and a discussion of the survival of planted shrubs. Bare areas would be noted during monitoring. The potential revegetation of the bare areas would be assessed, and recommendations would be made in the annual monitoring reports. Weed species, population size, and extent would be noted; and weed management recommendations would be made. Permanent photo points would be established and provided in the annual monitoring report. The annual monitoring report would include an evaluation of the status and progress of restoration and mitigation and any recommendations for remedial actions. Item 3A - WET2023-00010 City of Boulder Wetland Permit Application Fourmile Canyon Creek at 19th Street Boulder County, Colorado ERO Project #10675 20 ERO Resources Corporation References Brinson, Mark M. 1993. “A Hydrogeomorphic Classification of Wetlands.” Wetlands Research Program Technical Report WRP-DE-4. Vicksburg, Mississippi: Army Engineers Waterways Experiment Station. Cowardin, Lewis M., Virginia Carter, Francis C. Golet, and Edward T. LaRoe. 1979. “Classification of Wetlands and Deepwater Habitats of the United States.” FWS/OBS-79/31. Washington, D.C: Department of the Interior, U.S. Fish and Wildlife Service, Office of Biological Services Program. Environmental Laboratory. 1987. “Corps of Engineers Wetlands Delineation Manual.” Wetlands Research Program Technical Report Y-87-1. Vicksburg, Mississippi: U.S. Army Engineer Waterways Experiment Station. https://www.lrh.usace.army.mil/Portals/38/docs/USACE%2087%20Wetland%20Delineation%20 Manual.pdf. Google Earth. 2022. “Map Showing Project Area in Boulder County, Colorado.” earth.google.com/web. Land Stewardship Consulting, Inc. 2004. “City of Boulder Comprehensive Wetland Remapping Project.” Planning and Development Services, City of Boulder. U.S. Department of Agriculture, Natural Resources Conservation Service. 2023. “Web Soil Survey.” 2023. https://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm. U.S. Fish and Wildlife Service. 1992. “Interim Survey Requirements for Spiranthes Diluvialis.” ———. 2014. “Preble’s Meadow Jumping Mouse (Zapus Hudsonius Preblei) Trapping Database for Scientific Collection Activities Conducted under Section 10 of the Endangered Species Act.” Denver: Colorado Ecological Services Field Office. ———. 2023. “Information for Planning and Consultation (IPaC) Resource List.” 2023. https://ecos.fws.gov/ipac/. U.S. Geological Survey. 2019. “Boulder, CO.” Item 3A - WET2023-00010