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HomeMy WebLinkAboutFCLWD GOLDEN CURRANT WATER LINE - FDP200026 - - SUPPLEMENTAL INFORMATION (2) Conceptual Restoration Plan Golden Currant Waterline Project Page 1 Memorandum Date: January 13, 2021 To: Justin Beckner, PE, Project Manager – CivilWorx, LLC From: Sydney Shell, RLA – Pinyon Environmental, Inc. Subject: Conceptual Restoration Plan, Golden Currant Waterline Project, Fort Collins, Larimer County, Colorado Introduction The Fort Collins Loveland Water District is planning to install a new 30-inch waterline directly east of Horsetooth Reservoir in Fort Collins, Colorado (“project”; Figure 1). CivilWorx, LLC (CivilWorx), is providing the design services and Pinyon Environmental, Inc. (Pinyon), is providing environmental support services for the project, which includes the completion of this Conceptual Restoration Plan (CRP) as part of the Easement Application Packet. The project is located on the Maxwell Natural Area and on private land managed by a Ponds at Overland Trail Home Owner’s Association (HOA). Restoration of natural areas requires on-going coordination with the City’s Natural Area Department (NAD). Restoration of the remaining private land will also follow this CRP, but specific techniques or the seed mix may be amended after coordination with the private land manager and the City’s Land Conservation Manager. It is understood that CivilWorx is responsible for the Easement Application Packet: Mitigation and Compensation Section. When implemented properly, this CRP fulfills City of Fort Collins requirements and recommendations outlined in the Easement Application Packet: General Resource Protection Standards and Standards and Guidelines for Restoration of Utility Easements. Project Description and Location This project will install a new 30-inch-diameter waterline approximately six feet underground. The typical trench section will be about six feet wide with a trench box. Soil stockpiles, vehicle traffic, and surface disturbance will be limited to 30 feet on either side of the waterline (project area). Conventional excavation equipment, including diesel-powered hydraulic excavators and front-end loaders will be used to construct the new waterline. The project location is shown in Figure 1 and described in Table 1. Conceptual Restoration Plan Golden Currant Waterline Project Page 2 Table 1. Project Location Existing Site Vegetation On April 4, 2019 Pinyon conducted a biological resource assessment of the project area (Pinyon, 2019). Below is a summary of the general vegetation as identified during the 2019 biological resource assessment. Except for a small drainage swale northwest of the intersection between West Prospect Road and South Overland Trail, most of the project area consisted of uplands and was dominated by smooth brome (Bromus inermis) (Photo 1 in Photographic Log). Other herbaceous species noted in the upland areas included common mullein (Verbascum thapsus), downy brome (Bromus tectorum), intermediate wheatgrass (Thinopyrum intermedium), musk thistle (Carduus nutans), purple threeawn (Aristida purpurea) redstem filaree (Erodium cicutarium), sand dropseed (Sporobolus cryptandrus), twistspine prickly pear (Opuntia macrorhiza), and western wheatgrass (Pascopyrum smithii). Several shrubs and trees were noted in low densities throughout the project area uplands, including rubber rabbitbrush (Ericameria nauseosa), soapweed yucca (Yucca glauca), three leaf sumac (Rhus trilobata), plains cottonwood (Populus deltoides), ponderosa pine (Pinus ponderosa), and Russian olive (Elaeagnus angustifolia). One upland swale was noted within the project area and was vegetated by smooth brome (Photo 2 in Photographic Log). Wetland vegetation was uncommon within the project area, and generally present only within the drainage swale at the very eastern end of the project area, northwest of the intersection between West Prospect Road and South Overland Trail. This area encompassed 745 square feet within the project area and was dominated by coyote willow (Salix exigua) and bentgrass (Agrostis sp.); However, the project will be designed to avoid this area as much as feasible. Conceptual Restoration Plan Site Demolition and Topsoil Stockpiling During site demolition the Contractor shall provide the required documentation that equipment has been washed/disinfected prior to arriving on site to prevent the spread of noxious species. The Contractor shall strip and stockpile topsoil based on the following: • Native vegetation areas shall be excavated to a depth of 8 inches and stockpiled separately. City/County Fort Collins/Larimer U.S. Geological Survey (USGS) 7.5-Minute Quadrangle Horsetooth Reservoir, Colorado 1962, revised 1992 (USGS, 1992) Section, Township, and Range (6th Principal Meridian) Section 17, Township 7 North, Range 69 West Approximate Average Elevation of Project (feet above mean sea level) 5,200 Center Location of Project in Decimal Degrees (WGS84) 40.567441°, -105.142987° Conceptual Restoration Plan Golden Currant Waterline Project Page 3 • Non-native vegetation areas shall be stripped, and the top 2 inches will be removed to remove non- native seed source. Then and additional 8 inches shall be excavated and stockpiled separately. Grading Activities The Contractor shall seed all disturbed and topsoiled areas with the City-approved upland seed mix of native species (see below). Areas within the limits of disturbance that have been driven over, compacted, or rutted by equipment must be scarified to a depth of 8 inches (not exceeding 10 inches between intervals), and regraded to original grade and contours. Back-filled trenches shall be compacted to 95% Standard Proctor Density. The density test must follow the requirements set forth in the Easement Application Packet: Standards and Guidelines for Restoration of Utility Easements and submitted to the City for approval. After compaction to final subgrade (8 inches below finished grade), the top 6 inches of subsoil must be ripped (no more than 20 inches between intervals), and the previously stripped and stockpiled topsoil materials spread evenly over the excavated areas in the corresponding zones immediately following the completion of construction. Soils in backfilled, compacted, and topsoiled trenches must match the grade of the surrounding undisturbed areas. All topsoil, either imported or salvaged in the project area, shall be treated with an herbicide for noxious weeds prior to final seeding (ensure timing of herbicide application does not impact seed germination). A separate Integrated Noxious Weed Management Plan has been developed for the project (Pinyon, 2021). If requested by NAD, the contractor shall sample project soils and submit them for analysis to a qualified soil testing laboratory prior to the start of any seeding operations. As least one soil sample per project soil type must be collected. The location of soil samples shall be jointly determined by the Grantee and NAD. Soil samples shall be analyzed for the following minimum parameters: • pH • % Organic Matter • Texture (actual % sand, silt, clay, not an estimate) • Cation Exchange Capacity (CEC) • Nitrate, Phosphorous, Potassium, Zinc, Iron, Copper, and Manganese (results in parts per million [ppm]) The laboratory shall be informed of the species proposed to be planted and the general nature of the project. Based on this information, the laboratory shall provide written recommendations for soil amendments and/or fertilizers. This report shall be submitted to NAD, where it will be reviewed and approved or modified prior to any soil preparation or seeding. Fertilizer, if necessary, shall be specified by NAD after reviewing required soil test results. All fertilizer shall be a standard commercial product of uniform composition, free flowing and conforming to applicable State and Federal laws. It shall be delivered in original, unopened containers, unless provisions are made and approved by the NAD for bulk deliveries to the site of the work. The cost of any needed fertilizer will be negotiated. All fertilizer shall be approved by NAD prior to application. No cyanamide compounds will be permitted in Conceptual Restoration Plan Golden Currant Waterline Project Page 4 fertilizers. The Contractor shall submit to NAD the manufacturer's guaranteed chemical analysis, name, trade name, trademark, and conformance to state law of all fertilizers. The Contractor shall meet with the City’s representative to discuss and get written approval of the final grading and seeding/mulching process prior to reseeding. Seed Mixes and Seed Application All seed shall be mixed by a wholesale seed supplier in the proportions determined by NAD in order to obtain the application rate specified by NAD. All seed shall conform to all current State and Federal regulations and will be subject to the testing provisions of the Association of Official Seed Analysis. All seed and seed mixes shall be furnished in bags or containers clearly labeled to show the name and address of the supplier, the common, scientific, and variety name(s) of the seed(s), the lot number, point of origin, net weight, percent of weed content, and the guaranteed percentage of purity and germination. These labels shall be submitted to NAD for approval prior to seeding. The Grantee shall furnish to NAD a signed statement certifying that the seed furnished is from a lot that has been tested by a recognized laboratory for seed testing within six months prior to the date of delivery. The following seed mix has been approved by NAD for use in the Maxwell Natural Areas. The project will coordinate with the land manager and the City’s Land Conservation Manager to review, approve, and potentially amend this seed mix for use on the private land within the project area. Conceptual Restoration Plan Golden Currant Waterline Project Page 5 The Contractor shall use this seed mix to drill-seed into the soil to an approximate depth of ¼ to ½ inch, using a range drill (not a Brillion). Immediately following seeding the contractor shall roll the seeded areas with a sheep’s foot roller to lightly compact and imprint the soil to remove air voids, provide better seed-soil contact and create indentations in the soil that will capture moisture. All seeded areas shall be hydromulched in accordance with the City’s Storm Drainage Design Criteria and Construction Standards. The contractor shall obtain and submit to the project manager certifications from suppliers of hydraulic mulch that laboratory and field testing of their product has been accomplished, and that it meets all the foregoing requirements pertaining to wood cellulose fiber mulch. Conceptual Restoration Plan Golden Currant Waterline Project Page 6 Success Criteria All seeded areas shall be inspected jointly by the Contractor and NAD at specified intervals: • Areas seeded in the Spring shall be inspected for required coverage the following Fall, no later than October 1st. • Areas seeded at any other time shall be inspected the following two Summers, no later than August 1st. Due to the linear nature of the project and the natural area made up of predominately smooth brome, the following proposed success criteria will need coordination and approval by NAD: • 25% relative coverage (relative to an adjacent/undisturbed “reference” area) at first inspection. • 50% relative coverage (relative to an adjacent/undisturbed “reference” area) at second growing season inspection. The natural area and private land shall be held to the same success criteria. The Contractor shall follow inspection requirements set forth in the Easement Application Packet: Standards and Guidelines for Restoration of Utility Easements. Maintenance Following final grading and initial seeding of the project area and acceptance by the City, the City will be responsible for ongoing vegetation management, including weed control, mowing, and reseeding, as needed, in areas disturbed and seeded for natural areas only. When the contractor is issued a conditional letter of acceptance as defined above, and the monies are paid, the City will assume maintenance responsibility for the revegetated natural area. This acceptance does not relieve the Contractor from the warranty of the work. The Contractor shall be responsible for ongoing vegetation management, including weed control, mowing, and reseeding, as needed, in areas disturbed and seeded to meet the success criteria on private property. Warranty The Contractor shall warrant all seeded areas against defective materials and workmanship for two growing seasons from the date of conditional acceptance. At any time during the warranty period, NAD may order any samples collected at the time of seeding to be tested for purity, weed content, species present, etc. The Contractor shall be responsible for the cost of these tests. The Contractor shall rework and reseed (in accordance with the provisions in the original project specifications) any areas that are dead, diseased, contain too many weedy species, or in the opinion of NAD are in an unhealthy condition as a result of defective materials or workmanship, at no cost to the City. Reseeding or other required remedial measures shall be completed within ten days of notification by NAD. Attachments Figure 1. Project Location Conceptual Restoration Plan Golden Currant Waterline Project Page 7 References Pinyon, 2019. Biological Resources Memorandum, Golden Currant Waterline Project, Fort Colins, Larimer County, Colorado. Completed by Pinyon Environmental, Inc. for CivilWorx, LLC, dated April 24, 2019. Pinyon, 2021. Integrated Noxious Weed Management Plan, Golden Currant Waterline Project, Fort Collins, Larimer County, Colorado. Completed by Pinyon Environmental, Inc. for CivilWorx, LLC, dated January 13, 2021. USGS, 1992. 7.5-Minute Topographic Map, Horsetooth Reservoir, Colorado. U.S. Geological Survey, 1962. Revised 1992. Figure: 1Drawn By: PJW Reviewed By: BC APinyon Project Number: 1/19-1260-01 Site Location: Section 17, Township 7 North, Range 69 West, 6th Principal Meridian Date: 1/7/2021 Document Path: Z:\PROJECTS\2019\119126001 Golden Currant Waterline - Fort Collins\Figures\ArcMap\MXDs\Bio\Bio01_ProjectLocation.mxd I Project Area 0 2,0001,000 Feet Golden Currant WaterlineFort Collins, Colorado PROJECT LOCATION ^_ PROJECT LOCATION Legend Service Layer Credits: Copyright:© 2013 National Geographic Society, i-cubedSources: Esri, HERE, Garmin, USGS, Intermap, INCREMENT P, NRCan, Esri Japan, METI, Esri China (Hong Kong), Esri Korea, Esri (Thailand), NGCC, © OpenStreetMap contributors, and the GIS User Community Project Area bNotes:USGS 7.5' Topographic MapHorsetooth Reservoir, 1962 (Revised 1992)