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HomeMy WebLinkAboutWHITHAM PROPERTY - ODP - 24-02B - SUBMITTAL DOCUMENTS - ROUND 1 - ENVIRONMENTAL REPORT' consisting of dead wood. This tree could pose a health and safety risk to people or structures in the near future and may need to be removed prior to development. Because of its isolated location, this large ' cottonwood tree would also provide little wildlife habitat value if the Whitham Property is developed. 11 (h) There are no suitable wildlife movement corridors on the property, but the adjacent Cooper Slough drainage is a potential movement corridor for urban -adapted wildlife and some waterfowl species between East Vine Drive and East Mulberry. There is no suitable vegetation cover on the property to attract wildlife out from Cooper Slough except for Canada goose and some other waterfowl species that would forage in row cropland when grain crops are present. Row cropland has been developed immediately adjacent to the railroad right-of-way that bisects the property, and railroad the right-of-way does not support sufficient vegetation cover to provide a suitable wildlife movement corridor. ■ 5.0 WILDLIFE MITIGATION RECOMMENDATIONS ' Development plans for the Whitham Property would involve the conversion of most of the property to residential development and a neighborhood park. All development would be within row cropland, non- native grassland, and disturbed habitat areas. Therefore, there would be no direct impacts to important wildlife habitats or special habitat features with the Whitham Property. The proposed development would also have no indirect effect on Cooper Slough as long as best management practices are employed ' during construction to preclude untreated runoff and sedimentation impacts into the slough. ' One City of Fort Collins Land Use Code (Section 3.4.1) buffer setback requirement applies to the property. Because Cooper Slough has been identified as a waterfowl concentration area, a 300-foot development setback from Cooper Slough has been established by the City of Fort Collins. A 300-foot ' buffer would encroach into the eastern edge of the project area. As long as an average of 80 percent of a 300-foot development setback is maintained from the slough, project development approval should not ' need to request of variance from this requirement. If project development requires a buffer setback of less than an 80 percent average from Cooper Slough, then a variance would need to be obtained from the ' Planning and Zoning Board in order for proposed development to be approved. Approval of a variance to the 300-foot buffer standard would require the implementation of sufficient mitigation in the buffer zone so that City of Fort Collins Performance Standards in Section 3.4.1 of the Land Use Code are met. ' Possible mitigation measures could be the creation of vegetation and topographic barriers to minimize the effects of the proposed development on habitat and wildlife use in the slough. ' The only other mitigation recommendations provided for proposed development in the Whitham Property is that native shrubs and trees as well as herbaceous species be planted in the buffer zone between the ' development and Cooper Slough to enhance this portion of the Cooper Slough corridor. Plantings of shrubs and trees would create visual screening between the creek and proposed development sites and ' improve existing habitat conditions along the slough. Finally, native cottonwood trees greater than 6 inches in diameter should also be preserved if judged to ' be significant by the City Forester. Significant trees that cannot be preserved would have to be mitigated with replacement trees according to Section 3.2.1 of the Land Use Code. The one mature and very large ' cottonwood adjacent to the railroad right-of-way is partially decadent with about half of the lower trunk 10 Mulberry is more limited. Along these segments, the drainage supports minimal vegetation cover and exhibits characteristics more typical of managed irrigation ditches. 4.0 ECOLOGICAL STUDY CHARACTERIZATION CHECKLIST The following provides a summary of information required by Fort Collins Land Use Code under 3A.1 (D) (1) items (a) through (i). Items Q) and (k) are addressed under following section, 5.0 Wildlife Mitigation Recommendations. (a) Wildlife use of the area is described in Section 3.0. (b) No wetlands are supported on the property. The only wetlands within 500 feet of the property are along the Cooper Slough drainage that runs near portions of the eastern property boundary (c) No views of significant topographical features are provided from the property although partial views of the Front Range foothills are available from some areas. (d) The only significant native trees on the property are cottonwoods greater than 6 inches in diameter. The locations and sizes of these trees are noted on Figure 2. No other sites of significant native vegetation are located on the property. ■ (e) Cooper Slough is the only natural drainage located within 500 feet of the property ' (f) Because of past agricultural conversion of the property, there is no evidence of the presence of specially valued species or their habitats within the property boundaries. Wetland and aquatic habitats ' along Cooper Slough represent the only important wildlife habitats within 500 feet of the property. Wetlands along portions of Cooper Slough adjacent to the Whitham Property were evaluated for potential habitat for two federal listed threatened species, Preble's meadow jumping mouse (Zapus hudsonius ' preblei) and Ute ladies' -tresses orchid (Spiranthes diluvialis). The evaluation indicated that suitable habitat conditions are not present in this portion of the slough for either the Ute ladies' -tresses orchid or Preble's ' meadow jumping mouse. Saturated wetland sites without standing water support wetland vegetation that is too tall and dense to provide suitable habitat for Ute ladies' -tresses orchid. Suitable habitat conditions ' for Preble's meadow jumping mouse also do not exist because there is an abrupt transition from wetlands and saturated soils to adjacent areas of developed, cleared, or non-native grassland habitats not favored by Preble's meadow jumping mouse. Further, the slough and adjacent uplands do not support low lying twoody vegetation and riparian habitats preferred by the jumping mouse. (g) Because of past disturbances and development, there are no special habitat features on the property 9 t Photo 3. View of the Disturbed - Soil Borrow Area in the Whitham Property. (Puddle is from recent rainstorm. Note minimal weedy vegetation cover.) Photo 4. View of Cooper Slough and Wetlands Near the Eastern Boundary of the Whitham Property. (View is looking north toward the Imu-Tek commercial facility.) 9 ' cheatgrass, kochia, yellow sweetclover (Melilotus officinale), Canada thistle, curly -cup gumweed (Grindelia squarrosa), and Russian thistle (Salsola australis). This area has little value as wildlife habitat because of ' recent disturbance and the general lack of vegetation cover. Photo 3 provides a view of the disturbed — soil borrow area. 3.4 Cooper Slouah Although no important or sensitive wildlife habitats exist on the Whitham Property, Cooper Slough is located near the eastern property boundary. The slough supports wetlands and open water areas that are seasonally utilized by waterfowl and shorebird species. Wetlands in the slough are dominated by broad - leafed cattail (Typha latifolia), Nebraska sedge (Carex nebracensis), Emory's sedge (Carex emoryi), three - square (Schoenoplectus pungens), Baltic rush (Juncus balticus), creeping spikerush (Eleocharis ' paustris), and watercress (Nasturtium officinale). Other less dominant but common species noted in adjacent areas of the Cooper Slough wetlands were softstem bulrush (Schoenoplectus lacustris creber), ' showy milkweed (Asclepias speciosa), rabbit -foot grass (Polypogon monspeliensis), and smartweed (Perisicaria sp.). Distribution and dominance by wetland vegetation appears to be dependent on the extent of soil saturation and standing water present along the length of the slough. In areas of deeper, ' running water, watercress is dominant. Threes-quare and Nebraska sedge are the most prevalent species in saturated but not flooded areas. In slightly flooded, standing water areas, broad -leafed cattail is the tdominant species. Wetland transition areas between wetter portions of the slough and adjacent uplands of non-native grassland support primarily Baltic rush as well as foxtail barley (Hordeumjubatum) and alkali muhly (Muhlenbergia asperifolia). Near the southeast property corner, wetlands associated with Cooper ' Slough are dominated by nearly monotypic, dense stands broad -leafed cattail. Photo 4 provides a representative view of Cooper Slough wetlands adjacent to the Whitham Property. ' The Fort Collins Department of Natural Resources has designated Cooper Slough as a waterfowl concentration area. The most diverse and valuable habitat areas for waterfowl and shorebirds within the ' Cooper Slough drainage are created by areas supporting a diversity of wetland vegetation intermixed with areas of open, shallow water. Dense monotypic stands of broad -leafed cattail represent the least valuable ' habitat areas for waterbirds. Waterfowl and shorebird use of the slough varies by season, and according to the Fort Collins Department of Natural Resources and the Colorado Division of Wildlife, the wetland ' habitats within the slough are most important for waterbirds during the late fall and winter. Ground water that flows into the slough keeps some portions of the slough free of ice into mid -winter, and these ice - free, open water areas within the wetlands provide important late fall and winter foraging and resting habitat for resident and migratory waterfowl and shorebirds. Cooper Slough may also serve as a minor movement corridor for mammalian species such as raccoon, ' striped skunk , coyote, red fox, and white-tailed deer between East Mulberry (Highway 14) and East Vine _ Drive. Cooper Slough's value as a wildlife movement corridor north of East Vine Drive and south of East 7 Although row cropland is undeveloped land and represents open space for wildlife populations, it has limited value as wildlife habitat since vegetation cover and food sources are present primarily on a short- term basis due to seasonal harvesting and cultivation. The primary value of agricultural land as wildlife habitat is that it contributes seasonal food sources for small mammals and avian species during the growing season. Crop residue remaining after harvest also provides a food source for small mammals, songbirds, and waterfowl such as Canada goose. Mule deer and white-tailed deer will occasionally forage in cropland habitats as well when areas of adjacent suitable cover are available. Mice, voles, and ground squirrels are the only species likely to establish resident populations in cropland and the weedy edge areas. Open -country raptors including red-tailed hawk, Swainson's hawk, northern harrier, and great horned owl and mammalian predators like coyote, striped skunk, and red fox will occasionally hunt row cropland habitats 3.2 Non-native Grassland Non-native grassland is located near the northwest property corner around the perimeter of the disturbed soil borrow area (see Figure 2). Non-native grassland in the project area is dominated by smooth brome (Bromopsis inermis) and weedy species including cheatgrass, field bindweed, common dandelion, kochia, Canada thistle (Breea arvensis), and flixweed. Other common but less dominant species noted in non-native grassland were alfalfa (Medicago sativa), musk thistle (Carduus nutans), many -flowered aster (Virgulus ericoides), and crested wheatgrass. Western wheatgrass (Pascopyrum smithil) was the only native grass species recorded in non-native grassland, but it was not dominant. The only woody species observed in non-native grassland were a few rubber rabbitbrush (Chrysothamnus nauseosus) shrubs as well as a few sapling -sized Siberian elms (Ulmus pumila) and native cottonwood trees (Populus deltoides). One small clump of chokecherry (Padus virginiana) shrubs also grows in non-native grassland. Waste piles of lumber, irrigation plastic sheeting, and other debris are also located throughout the non-native grassland area. Photo 2 provides a view of non-native grassland habitat in the Whitham Property. Habitat value and wildlife use of non-native grassland habitat is limited because of low vegetation species diversity and the relative lack of woody vegetation cover. Mice, thirteen -lined ground squirrel, prairie vole, northern pocket gopher, and western meadowlark are the only species likely to establish resident populations in non-native grassland. Songbirds such as Brewer's blackbird, common grackle, and black - billed magpie may also occasionally use non-native grassland habitat. There was no evidence of prairie dogs or prairie dog burrows observed in non-native grassland habitat, and the only evidence of wildlife presence were the numerous vole runways noted throughout the non-native grassland habitat areas. 3.3 Disturbed Area This area apparently has been disturbed to collect soil removal for use as borrow material at offsite areas. Vegetation supported in this area is relatively sparse and consists primarily of annual weeds such as 9 Photo 1. View of Row Cropland on the Whitham Property. (View is from railroad right-of- way looking east.) Photo 2. View of Non-native Grassland Habitat in the Whitham Property. (View is from south end of habitat area looking northwest along railroad right-of-way. Shrubs are rubber rabbitbrush. Trees are sapling Siberian elms. Note piles of lumber debris.) R v 11 t Alfalfa Hayfield Fallow / Weedy _ Wetland9 i.. Disturbed /! -t R Weedy x Alfalfa Hayfield Disturbed R —_ Cooper Slough ast ine rive Disturbed -- Soil I Borrow Siberian C � Area Disturbed / Bare elms Disturbed Siberian Bare elms NNG 3 Cottonwoods (1.5' - 2.5' dbh) j NNG Row Cropland Railroad right-of-way Cooper Slough & Wetlands Row Cropland PHayfield Cottonwood (5' dbh, NNG a partially decadent) NNG Disturbed 7 and & Gravel A. �j NNG Row C jnd Weedy IU LEGEND =AMA Property Boundary-. �v.,m� •�».-, Habitat Boundary FIGURE 2 NNG = Non-native Grassland R = Residential Habitat Mapping for the C = Commercial Whitham Property Scale: 1 " = -515' Date of aerial photography: April 2003 4 None of these soils are classified as hydric (wetland) soils by the SCS. They are deep, well -drained soils, and wind and water erosion hazard is rated as slight to moderate for all these soil mapping units except for the steeper sloped (5 to 9 %) Fort Collins Loams. The erosion hazard for Fort Collins loam, 5 to 9 % slopes is rated as severe by the SCS. No problem erosion sites were noted during the field survey of the property. Topography of the project site is relatively flat and gently sloping to the southeast. A relatively steep embankment is located along most of the northern property boundary adjacent to the south edge of East Vine Drive. Another small area of steeper slopes historically existed south of East Vine Drive and east of the existing railroad right-of-way. This area corresponds to the Disturbed — Soil Borrow Area shown on Figure 2 and SCS soil mapping units Fort Collins loam, 3 to 5 % slopes and Fort Collins loam, 5 to 9 % slopes. Slopes over much of this area have been altered by soil removal from this site. The remainder of the soil mapping units are associated with the more level row cropland sites. ' Current habitat and land uses within the Whitham property consist almost entirely of row cropland. A small area of non-native grassland and a disturbed, soil borrow site is located near the northwest property corner ' (see Figure 2). Surrounding land uses and habitats are comprised of row cropland, alfalfa hayfield, non- native grassland, disturbed sites, residential and commercial developments, railroad right-of-way and roadway, and the Cooper Slough drainage and associated wetlands. Cooper Slough represents the only t sensitive or important wildlife habitats near the Whitham property. The following sections summarize the characteristics of habitats in the project area and wildlife use of the site. 3.1 Row Cropland Row cropland occupies the majority of the project area. These portions of the property have been planted to row crops such as corn or winter wheat. Cultivation practices in row cropland have resulted in the removal of native vegetation and the invasion of plants consisting primarily of non-native, weedy grass and forb species around the perimeter of the fields. Non-native and other weedy upland species noted along the cultivated field edges included crested wheatgrass (Agropyron cristatum)t, cheatgrass (Anisantha tectorum), common dandelion (Taraxacum officinale), field bindweed (Convolvulus arvensis), kochia (Bassia sieversiana), flixweed (Descurainia sophia), blue mustard (Chorispora tenella), and Canada thistle (Breea arvensis). Vegetation cover in row cropland is typically lacking from fall through early spring. At the time of the April field survey, vegetation in row cropland was essentially lacking except for fields exhibiting winter wheat seedlings. Photo 1 provides a view of row cropland habitat in the project area. 1 Vegetation nomenclature follows: Weber, W.A. and R.C. Wittmann. 1996. Colorado Flora, Eastern Slope (revised edition). University Press of Colorado, Niwot Colorado. 524 pp. 3 No Text ECOLOGICAL CHARACTERIZATION STUDY REPORT FOR THE WHITHAM PROPERTY ' 1.0 INTRODUCTION AND LOCATION This report provides an evaluation of wildlife habitat conditions in and within 500 feet of the Whitham Property in accordance with Section 3.4.1 of the Land Use Code of the City of Fort Collins regarding the preparation of an Ecological Characterization Study Report for properties proposed for development. The majority of the property is planned to be developed as residential properties and a neighborhood park. The parcel of land addressed by this report consists of primarily agricultural land south of East Vine Drive and west of Cooper Slough in Fort Collins, Colorado. The property is located in the northwest 1 /4 of Section 9 (T. 7 N., R. 68 W.), and the project area location is depicted on Figure 1. This report summarizes the findings of the field evaluation, documents environmental conditions and habitats on the property, discusses potential impacts associated with the proposed development, and provides recommendations for mitigation. 2.0 METHODOLOGY Cedar Creek completed a field survey of the proposed development parcel on April 25, 2003. The field survey was conducted to characterize existing wildlife habitats, as well as identify any unique or sensitive natural resource features. Prior to the initiation of the field survey, Natural Resources Conservation Service (formerly SCS) soils mapping (Soil Survey of Larimer County Area, Colorado) was reviewed to determine if any known hydric (wetland) or highly erosive soil mapping units are located on the property. Observations recorded during the field evaluation included: major vegetation communities / wildlife habitats present within the property; dominant vegetation associated with each community / habitat; unique habitat features; and observations of wildlife species and/or definitive sign Photographs showing representative views of existing habitats were also taken to document site conditions. Wildlife presence and habitat use was based on on -site observations and habitat presence in conjunction with the known habitat requirements of potential wildlife species. Existing habitats were also evaluated regarding their ability to support populations of threatened, endangered, and other sensitive plant and wildlife species. 3.0 HABITAT CONDITIONS AND WILDLIFE USE According to the Soil Survey of Larimer County Area, Colorado (SCS 1980), the following seven soil map units are present on the Whitham Property. Ascalon sandy loam, 0 to 3 % slopes Fort Collins loam, 5 to 9 % slopes Ascalon sandy loam, 3 to 5 % slopes Kim loam, 3 to 5 % slopes Fort Collins loam, 1 to 3 % slopes Otero sand loam, 0 to 3 % slopes Fort Collins loam, 3 to 5 % slopes TABLE OF CONTENTS Page 1.0 Introduction and Location.. ......................................................................................................... 1 2.0 Methodology.............................................................................................................................1 3.0 Habitat Conditions and Wildlife Use..............................................................................................1 3.1 Row Cropland.......................................................................................................................3 3.2 Non-native Grassland..................................................................................... ....................6 3.3 Disturbed Area.....................................................................................................................6 3.4 Cooper Slough.....................................................................................................................7 4.0 Ecological Study Characterization Checklist.................................................................................9 5.0 Wildlife and Habitat Mitigation Recommendations.......................................................................10 ECOLOGICAL CHARACTERIZATION STUDY REPORT FOR THE WHITHAM PROPERTY Prepared by Cedar Creek Associates, Inc. Fort Collins, Colorado Prepared for David Whitham & bha design Fort Collins, Colorado April 29, 2003 pW®Vq` M' INC. - 916 Willshire Ave,, Fort Collins, CO 60521 • (970) 493-4394