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HomeMy WebLinkAboutRENNAT - FDP200006 - SUBMITTAL DOCUMENTS - ROUND 3 - WETLANDS DOCUMENTSRennat Wetland Monitoring Plan RENNAT DEVELOPMENT April, 2020 Presented to: Post Modern Development, Inc. 114 N Mason St. Suite 5 Fort Collins, CO 80524 Prepared by: Wetland Monitoring Plan Rennat Property i TABLE OF CONTENTS 1.0 INTRODUCTION ....................................................................................... 1 1.1 Site Setting ............................................................................................. 1 1.2 Wetlands Description ............................................................................... 1 2.0 MONITORING PLAN COMPONENTS ......................................................... 3 2.1 Hydrology Monitoring Component ............................................................. 3 2.2 Soil Monitoring Component ....................................................................... 3 2.3 Vegetation Monitoring Component ............................................................ 4 2.4 Monitoring Report .................................................................................... 4 3.0 SUCCESS DETERMINATION ..................................................................... 6 4.0 REFERENCES ............................................................................................ 7 Wetland Monitoring Plan Rennat Property 1 1.0 INTRODUCTION Cedar Creek Associates, Inc. (Cedar Creek) is contracted to provide ecological support by developing an approach for monitoring the existing wetland on the Rennat Property (Property). The wetlands occur on the west side of the site where there are wet meadow and emergent wetlands surrounding an old livestock pond. The total area of the wetlands is 8.37 acres, as delineated by Professional Wetlands Consulting, Inc. in 2019. The Army Corps of Engineers issued a Jurisdictional Determination for the property on November 14, 2019, which declared the pond and associated fringe wetlands as not jurisdictional. According to the ecological characterization study, the wetlands are moderate to high quality wetlands with a diversity of native vegetation. Wetlands will be preserved and protected with the required buffer zone as part of the development. However, a groundwater and vegetation monitoring plan is needed to understand if and how the project can ensure the wetlands are protected including evaluation of the hydrology, soils, and vegetation factors which contribute to the delineated wetlands at the site. 1.1 Site Setting The Property encompasses 57.83 acres of agricultural plains grassland with an old livestock pond and wetlands on the west side of the site. The Rennat project is bounded by roads, residential development, and undeveloped land. Railroad tracks border the west property boundary. The primary use of the land has been agricultural, with hay meadows and livestock pasturing occurring. The Rennat project is located in Section 7, Township 6 North, Range 68 West of the 6th Principal Meridian in Larimer County, Colorado. 1.2 Wetlands Description Dominant wetlands vegetation at the Rennat property includes plains cottonwood trees (Populus deltoides), peachleaf willow trees (Salix amygdaloides), sandbar willows (Salix exigua), reed canary grass (Phalaris arundinacea), smartweed (Polygonum species), spikerush (Eleocharis palustris), curly dock (Rumex crispus), duckweed (Lemna species), Nebraska sedges (Carex nebrascensis), hard stem bulrushes (Schoenoplectus acutus), three square (Schoenoplectus americanus), baltic rushes (Juncus balticus), scouring rush (Equisetum hyemale), and cattails (Typha latifolia). Hydric soils are present in the wetlands, with soil colors corresponding to 10yr 3/2, and 10yr 2/2 on the Munsell Soil Color Charts. Redoxymorphic features are generally present in the wetland soils, and soil texture is sandy loam with gravel and cobbles. Wetlands hydrology sources include irrigation ditch water, stormwater drainage, and groundwater seepage. Wetland Monitoring Plan Rennat Property 2 The Rennat property wetlands are classified as Palustrine, Emergent Wetland. Functions and values of the wetlands include shoreline anchoring, within basin food chain support, flood storage, groundwater discharge, wildlife habitat, passive recreation, long term nutrient retention, and short- term nutrient retention. Wetland Monitoring Plan Rennat Property 3 2.0 MONITORING PLAN COMPONENTS The monitoring plan includes evaluation of the hydrology, soils, and vegetation factors which contribute to the delineated wetlands at the site. Monitoring will begin in the pre-construction period from April-September and extend for 3 years post-construction. 2.1 Hydrology Monitoring Component According to the Supplemental Subsurface Exploration and Groundwater Report provided by Earth Engineering Consultants, LLC. in August 2019, Groundwater was encountered across the site within the preliminary borings at approximate depths of 5 to 15 feet below existing site grades. Based on their findings, the groundwater piezometric flow is in the southeast direction and ranges in elevation from 4,956 to 4,930 feet while the ground surface ranged from 4,962 to 4,940 feet. Perched and/or trapped water may be encountered in more permeable zones in the subgrade soils at times throughout the year. Perched water is commonly encountered in soils immediately overlying less permeable bedrock materials. Fluctuations in ground water levels and in the location and amount of perched water may occur over time depending on variations in hydrologic conditions, irrigation activities on surrounding properties. The groundwater appears to be an important factor for the sustainability of the delineated wetlands on the property. Cedar Creek proposes to establish five monitoring well sites to be located in uplands upslope from the delineated wetlands. The proposed well locations were selected to coincide with the data points used to delineate the wetland communities by Profession Wetland Consulting, Inc. Each well should be drilled to a depth of 10 or 20 feet to ensure interception of groundwater and lined with a 2-inch diameter PVC pipe. The wells should also constructed with an above ground metal casing with a lock to prevent tampering. Monitoring should occur on a semi-monthly basis during the growing season beginning on or about April 1 and ending on or about September 30 for a total of 13 yearly monitoring visits. During each monitoring visit, the depth to groundwater is to be measured in each of the five drilled wells. The results of each individual monitoring visit are sent electronically to the City of Fort Collins and relevant stakeholders. 2.2 Soil Monitoring Component During the wetland delineation effort in 2019 by Professional Wetland Consulting, Inc., soils were found to be exhibiting hydric features, with soil colors corresponding to 10yr 3/2, and 10yr 2/2 on the Munsell Soil Color Charts. Redoxymorphic features were generally present in the wetland soils, and soil texture is sandy loam with gravel and cobbles. Wetland Monitoring Plan Rennat Property 4 Once per year, a soil pit (co-located with the groundwater well) in the wetland will be excavated to document the soil features in accordance with the 1987 Corps of Engineers Wetland Delineation manual and the 2010 Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Great Plains Region. 2.3 Vegetation Monitoring Component As described in Section 1.2, the delineated wetlands exhibited vegetation indicative of wetlands. Vegetation monitoring will consist of ocular estimates of vegetation cover and composition (dominant species) in the existing wetlands should be collected during the initial monthly visit at the five vegetation plot sites. A photo is taken of each plot once a month at the time of the vegetation analysis. 2.4 Monitoring Report An annual monitoring report will be prepared with findings to date for submittal to the City of Fort Collins each year by October 31. Cedar Creek will be available to respond to any questions or comments related to the monitoring program. Wetland Monitoring Plan Rennat Property 5 Wetland Monitoring Plan Rennat Property 6 3.0 SUCCESS DETERMINATION The objective of this monitoring program is to generate groundwater, soils, and wetland vegetation community characteristics data with which to determine whether site development will lead to a negative, indirect impact on downslope wetlands. Ultimately, the monitoring program will be considered successful if the project meets its 1:1 wetland mitigation requirement post-construction and results in at least 8.37 acres of delineated wetlands. Wetland Monitoring Plan Rennat Property 7 4.0 REFERENCES Earth Engineering Consultants, LLC. 2019. Supplemental Subsurface Exploration and Groundwater Report - Rennat Property. Professional Wetland Consulting, Inc. 2019. Ecological Characterization Study for the Rennat Property in Fort Collins, Colorado. USACE. 1987. Corps of Engineers Wetland Delineation Manual. USACE. 2010. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Great Plains (Version 2.0). USACE. 2019. Jurisdictional Determination for the Rennat Property in Fort Collins, Larimer County Colorado.