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HomeMy WebLinkAboutWILLOX FARM - FDP240005 - SUBMITTAL DOCUMENTS - ROUND 1 - ECS Report (2) 937 Mallard Drive, Ft. Collins, CO 80521 | (970) 224-0851 www.bluemountainenvironmental.com December 15, 2023 Colorado Holdings, LLC 4040 Mac Arthur Blvd. Suite 200 Newport Beach, CA 92660 RE: Magpie Meander Natural Area Ecological Characterization Study (Willow Farm Residential Development) To Whom It May Concern: This report is submitted to satisfy the requirements of Section 3.4.1 (D) (1) of the Land Use Code of the City of Fort Collins regarding the preparation of an Ecological Characterization Study (ECS). This report is required by the City of Fort Collins Community Development and Neighborhood Services Department for the Willox Farm Residential Development because stormwater from the proposed development would be delivered to the Poudre River via an oxbow channel located on the City of Fort Collins Magpie Meander Natural Area. The project is also proximal to the City of Fort Collins Soft Gold Park. The property is situated in the Southeast ¼ of the Northwest ¼ of Section 2, Township 7 North, Range 69 West of the 6th Principal Meridian in Larimer County, Colorado (Larimer County parcel numbers 9702200935, 9702205901, 9702208902). The proposed project is further described in the Willox Farm Preliminary Development Plan prepared by TB Group dated May 24, 2022, here incorporated by reference. The property was visited by Matt Tobler and Craig Severn with Blue Mountain Environmental Consulting on November 16, 2023. Feel free to contact me with any questions you may have. Sincerely, Matt Tobler Natural Resource Specialist, Certified Ecologist Blue Mountain Environmental Consulting, LLC Magpie Meander Natural Area Ecological Characterization Study 2 1.0 Project Background The Magpie Meander Natural Area is approximately 24 acres and is bounded by McMurry Natural Area and private property to the south, private rural properties to the west and north and Soft Gold Park to the east. The natural area derives its name from the “oxbow” present on the property, an artifact of a past meander of the Cache la Poudre River. The meander has evolved into a small, creek channel oxbow in which water appears to flow year-long. A proposed residential development located on 20 acres to the north of the Magpie Meander Natural Area is proposing to pass storm water generated within the development south into a raingarden and detention pond that would subsequently release water to the oxbow channel within the natural area, then to the Poudre River. The anticipated maximum discharge in the event of a 100-year storm would be 8.09 cubic feet per second. The detention pond would be drained within 120 hours. According to City of Fort Collins hydrologists, a two storm would result in a 0.14 to 0.18 foot rise in water depth within the oxbow in Magpie Meander. A Natural Habitat and Features Maps and Photo Point Map are provided in Appendix A. Photo points are in Appendix B. Figure 1. Magpie Meander Natural Area is approximately 24 acres in size. Properties to the south of the natural area include the McMurry Natural Area and Salyer Natural Area. Magpie Meander Natural Area Ecological Characterization Study 3 2.0 Ecological Characterization The elements of this Ecological Characterization Study are summarized in this section in the order listed in Section 3.4.1 (D) (1) of the Land Use Code. Natural Habitat Features and Photo Point maps are provided in Appendix A; site photos are provided in Appendix B. 2.1 Wildlife A variety of habitats suitable for wildlife is present in the Magpie Meander Natural Area. The north boundary and eastern portion of the natural area support a riparian forest with mixed-age stands of willow (Salix spp.) and cottonwood (Populus spp.). A small, flowing-water creek channel and wetland fringe passes through the forested area in an oxbow meander of the Cache la Poudre River. A small pond located in the southeastern corner of the natural area has approximately 1.1 acres of open water and is known as Wood Duck Pond. The western half of the property is grassland supporting a variety of native and introduced species. The properties to the south of the natural area include the McMurry Natural Area and Salyer Natural Area, which contain two additional ponds, riparian forest areas and border the Cache la Poudre River. More than 90 acres of habitat available for wildlife use is provided by these three natural areas. Seasonal and/or year-round use can be expected by a number of avifauna including American robin (Turdus migratorius), northern flicker (Colaptes auratus), mourning dove (Zenaidura macroura), western kingbird (Tyrannus verticalis), magpie (Pica pica), crow (Corvus brachyrhynchos) and raven (Corvus corax). During the site visit, several pairs of mallards (Anas platyrhynchos) were observed feeding in the small creek and Wood Duck Pond. Raptors may utilize the site primarily for hunting rodents and small birds. Mature trees on the property provide nesting cavities and potential locations for stick nests. No stick nests were observed in the natural area during the site visit. What appeared to be an active red fox (Vulpes vulpes) burrow was observed in the riparian forest area, and game trails made by small mammals (likely red fox) were common. Several white-tailed deer (Odocoileus virginianus) were observed passing through the area and several small trees showed signs of antler rubbing by deer. Other mammals such as mule deer (Odocoileus hemionus), coyote (Canis latrans), striped skunk (Mephitis mephitis), mice, voles, fox squirrel (Sciurus niger), eastern cottontail rabbit (Sylvilagus floridanus) and raccoon (Procyon lotor) could utilize the property year-round. Habitat for a variety of aquatic invertebrates is present in the small creek and pond area. Invertebrates observed in the creek included freshwater scuds (of the order Amphopoda, family Gammaridae) which are often associated with more pristine waters, and freshwater leeches believed to be of the genus Helobdella of the family Rhynchobdellidae. The benthic muck in some reaches of the creek is largely unconsolidated up to several feet in depth. This organic substrate can provide habitat for other invertebrates such as chironomids (Diptera, Chironomidae), also known as non-biting midges, and other aquatic insects. The presence of feeding, dabbling ducks on the creek would suggest that the creek provides nutritional benefits Magpie Meander Natural Area Ecological Characterization Study 4 from aquatic invertebrates. Aquatic reptiles and amphibians such as frogs, toads, turtles and salamanders may also inhabit this environment. 2.2 Wetlands Mapping by the National Wetlands Inventory (U.S. Fish and Wildlife Service, 2023) showed one wetland in the area of Wood Duck Pond classified as PABFx (palustrine, aquatic bed, semi permanently flooded, excavated). The pond has approximately 1.1 acres of open water with a narrow herbaceous wetland fringe of reed canarygrass (Phalaris arundinacea), sedges (Carex spp.) and cattails (Typha spp.) around most of its perimeter. Stands of cottonwoods and willows are scattered around the perimeter of the pond. Several broader wetland areas supporting cattails are located along the east side of the pond. The pond has no channel inflows and appears to be supported hydrologically by ground water associated with the Cache la Poudre River corridor. A second wetland area is located along the small, flowing-water creek channel of the oxbow near the northern edge and eastern area of the natural area. Water appears to be in the creek channel year-round with flows approximated to be 1-2 cubic feet per second at the time of the site visit. The water appeared clear with no turbidity. Vegetation and the physical channel characteristics indicate that flow volumes in this channel remain relatively stable throughout the seasons, i.e., there were no signs of scour or drift deposits. This oxbow channel supports herbaceous wetland species dominated by reed canarygrass (Phalaris arundinacea), creeping bentgrass (Agrostis stononifera) and a few scattered stands of narrow-leaf cattail (Typha angustifolia). Mixed-age stands of cottonwood (Populus deltoides), crack willow (Salix fragilis) and thinleaf alder (Alnus incana) dominate the riparian forest along the creek. Aquatic vegetation in the channel included common duck weed (Lemna minor), starwort (Callitriche sp.), bugleweed (Lycopus sp.) and cutleaf waterparsnip (Berula erecta). 2.3 Prominent Views The Front Range foothills and Horsetooth Mountain are visible from some areas of the property. Other surrounding views are of Soft Gold Park and residential neighborhoods to the east and agricultural land, including pastures, to the west and north. Many of the views from the middle of the property are of the riparian forest of the Cache la Poudre River corridor. 2.4 Native Trees and Vegetation Mixed-age stands of eastern cottonwood (Populus deltoides) are found in Magpie Meander Natural Area with some trees having a DBH of greater than 36 inches. The riparian forest along the eastern portion of the natural area also supports scattered stands of thinleaf alder (Alnus incana). Other native tree species include peachleaf willow (Salix amygdaloides) and green ash (Fraxinus pennsylvanica). A few scattered stands of the small shrub common snowberry (Symphoricarpos alba) were also observed. Native herbaceous vegetation includes showy Magpie Meander Natural Area Ecological Characterization Study 5 milkweed (Asclepias speciosa), indian hemp (Apocynum cannabinum) and scattered small stands of native grasses including little blustem (Schizachyrium scoparium), big bluestem (Andropogon gerardii) and blue grama (Bouteloua gracilis) in the grassland area of the western portion of the property. 2.5 Non-native Trees and Vegetation Several large, some decadent, crack willows (Salix fragilis) are present along the oxbow channel of the natural area and recruitment of younger crack willow is common in the riparian forest area. A few Siberian elm (Ulmus pumila) and small stands of Russian olive (Elaeagnus angustifolia) were also observed. Smooth brome (Bromus inermis) is the dominant grass and is found throughout Magpie Meander Natural Area; tall fescue (Festuca arundinacea) is found in areas of the riparian forest. Species on the Colorado Noxious Weeds list observed on the property included Canada thistle (Cirsium arvense) and leafy spurge (Euphorbia esula), but these were found only infrequently. 2.6 Bank, Shoreline and High Water Mark of Perennial Water According to the City of Fort Collins (2023a) Floodplain Maps and Documents website, the property is located on FEMA Map Panel 08069C0977G. Portions of Magpie Meander Natural Area, including the creek channel and Wood Duck Pond, are in a FEMA flood zone classified as ‘Flood Zone X with a moderate risk of flooding by a 500 or 100 year flood producing sheet flows of 1 foot or less.’ 2.7 Sensitive and Specially Valued Species The Magpie Meander Natural Area has potential habitat for Preble’s meadow jumping mouse (Zapus hudsonius preblei), such as dense shrub, grass and woody debris in riparian areas. The property has potential habitat (wetlands, floodplains) for Ute lady’s tresses orchid (Spiranthes diluvialis) and Colorado butterfly plant (Gaura neomexicana ssp. Coloradensis). There are no known occurrences of these three species on or near the property. No old or active prairie dog colonies that might provide habitat for burrowing owls (Athene cunicularia) are located on the property. Raptor stick nests were not observed on the property. Tufted loosestrife (Lysimachia thrysifolia) has been identified by the City of Fort Collins as occurring within Magpie Meander Natural Area. Few instances of this perennial have been recorded in Colorado; it is considered critically imperiled in Colorado, Wyoming and Utah. Tufted loosestrife is an obligate wetland species and would potentially be found in wetter areas associated with oxbow creek channel and the wetland fringe of Wood Duck Pond. Tufted loosestrife was not observed during the field survey of Magpie Meander Natural Area. Magpie Meander Natural Area Ecological Characterization Study 6 2.8 Special Habitat Features Magpie Meander Natural Area and the two adjacent natural areas to the south, McMurry and Salyer, total more than 90 combined acres and are part of the Cache la Poudre River riparian corridor. The Magpie Meander oxbow appears to have relatively stable perennial flows providing year-round habitat for aquatic species and appears to have little disturbance from human activities. Natural Habitat and Features Inventory data provided by the City of Fort Collins (2023b) shows areas in Magpie Meander Natural Area described as riparian forest, aquatic (Wood Duck Pond) and non-native grassland. A Natural Habitat Map is provided in Appendix A. 2.9 Wildlife Migration Corridors Magpie Meander Natural Area is in close proximity to the Cache la Poudre River riparian corridor, which provides a natural corridor for the movement of larger wildlife species including deer and bear as well as a flyway for a variety of birds using it for feeding, roosting and nesting. The continuous connection of habitat valuable to wildlife found in the natural area and its proximity to the river corridor enhances the value of the corridor by providing more opportunities for wildlife refuge. 2.10 General Ecological Functions A variety of habitat types within and surrounding Magpie Meander Natural Area, such as mixed- age riparian forest, grasslands, open water areas of the creek and pond, wetland fringe, and an adjacent migration corridor, provide vertical structure, thermal cover, nesting, roosting, denning, hunting and foraging opportunities for a variety of wildlife species. Slow-moving water within oxbow channels and ponds facilitate groundwater recharge and water purification. All undisturbed sites accommodate biogeochemical cycling while Magpie Meander Natural Area and Soft Gold Park preserve natural habitat connectivity along the Cache la Poudre River corridor. 2.11 Timing of Development in Relation to Ecological Character The primary concern for the timing of development is protection of migratory birds. Under the Migratory Bird Treaty Act of 1918, it is unlawful for anyone to take, possess, import, export, transport, sell, purchase, barter or offer for sale, purchase or barter, any migratory bird or the parts, nests or eggs. Observe the guidelines provided in section 2.12 regarding site activities (if any) at Magpie Meander Natural Area. Magpie Meander Natural Area Ecological Characterization Study 7 2.12 Mitigation Measures Blue Mountain Environmental Consulting recommends the following mitigation on Magpie Meander Natural Area. (Mitigation associated with construction of the proposed Willox Residential Development were addressed in a separate Ecological Characterization Study.) • Conduct a survey for nesting birds 10 days prior to site activities (if any) that occur between March 15 and August 15. • To the greatest extent possible, minimize disturbance to native trees that occur within the project area. • Locate, quantify and monitor existing populations of tufted loosestrife along all potentially affected reaches of the creek channel oxbow down to its confluence with the Cache la Poudre River. Monitor population size, location and numbers. • Provide measures to minimize the introduction of trash, sediment, oils and chemicals generated from the development to the downstream creek channel. • Manage noxious species within Magpie Meander as well as the proposed Willox development with integrated methods that include mechanical, cultural and, if necessary, chemical treatments. • Place three to five logs more than 10 or more inches in diameter in the grassy swale between the detention pond and the oxbow to reduce water velocity and promote infiltration. Logs should be placed approximately perpendicular to the direction of flow and extend from bank to bank. References City of Fort Collins. (2023a). Floodplain Maps and Documents [Utilities]. https://www.fcgov.com/utilities/what-we-do/stormwater/flooding/floodplain-maps- documents City of Fort Collins. (2023b). Free Downloadable GIS Data [Geographic Information Services]. https://www.fcgov.com/gis/downloadable-data Colorado Parks and Wildlife. (2020). Recommended Buffer Zones and Seasonal Restrictions for Colorado Raptors (p. 11). Department of Natural Resources. https://cpw.state.co.us/Documents/WildlifeSpecies/LivingWithWildlife/Raptor-Buffer- Guidelines.pdf Fort Collins Natural Areas Program. (2007). Wildlife Management Guidelines (p. 114). City of Fort Collins. http://www.fcgov.com/naturalareas/pdf/wildlife-management-guidelines.pdf U.S. Fish and Wildlife Service. (2023). Wetlands Mapper. National Wetlands Inventory. https://fwsprimary.wim.usgs.gov/wetlands/apps/wetlands-mapper/ Magpie Meander Natural Area Ecological Characterization Study 8 Appendix A: Maps 10 Magpie Meander Natural Area Ecological Characterization Study Appendix B: Site Photos 12 Photo Number: 1 Photo Direction: East View to the east from the northwest corner of property. Photo Number: 2 Photo Direction: East View to the east looking downstream from the northwest corner of property. This is the upper reach of the creek channel oxbow and riparian forest in the Magpie Meander Natural Area. 13 Photo Number : 3 Photo Direction: South View to the south from the northeast corner of property looking down the creek channel oxbow and riparian forest. Photo Number : 4 Photo Direction: North View to the north from the southern border of Magpie Meander looking upstream along the creek channel oxbow and riparian forest. 14 Photo Number : 5 Photo Direction: East View to the east looking along the southern boundary of the property from just east of the wetland channel. Photo Number : 6 Photo Direction: East View to the east from the southwest corner of property. 15 Photo Number : 7 Photo Direction: North View to the north from the southwest corner of property. Photo Number : 8 Photo Direction: North View to the north from the southeast corner of property looking over Wood Duck Pond. 16 Photo Number : 9 Photo Direction: South View to the south from the north side of Wood Duck Lake.