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HomeMy WebLinkAbout2009.07.00 - Ivy Street Final Monitoring Report Year 5ol Prepared for: City of Port Townsend 250 Madison Port Townsend, WA 98368 City of Port Townsend Ivy Street High Zone Water Main Project Final Monitoring RePort July 2009 Year 5 Olympic Wetland Resources, lnc dixie@cablespeed.com City of Port Townsend Ivy Street High Zone Water Main Project Final Monitoring RePort July 2009 Year 5 Table of Contents 1.0 Project History 1.1 Project Goals and Objectives 1.2 Planting and Maintenance 2.0 Monitoring MethodologY 2.1 Determining Survival Rates Using Monitoring Forms 2.2 Documenting Wetland Changes Using Photographs 3.0 Monitoring Schedule Table l. Monitoring and Maintenance Schedule 4.0 Results and Discussion 4.1 Survival Rate For Planted Species 4.2 Volunteer Species 4.3 Weedy Species 4.4 Maintenance and Watering 5.0 Summary Appendix Figure I. Monitoring Form Figure II. Photopoint Locations Figure III. Photopoints 1-3 Figure IV. Photopoint 4-7 City of Port Townsend Ivy Street High Zone Water Main Project Monitoring Report August 2008 Year 4 1.0 Project History This report fulfills the fifth and final year of a five year mitigation monitoring for the Ivy Street Water Main Project as required by the City of Port Townsend Ivy Street High Zone Water Main Connection Project, Delineation and Mitigation Plan, July 2004 Olympic Wetland Resourcesr lnc. (OWR). Monitoring was conducted on June 22,2009. The project site is located near the western city limit of Port Townsend, Washington between the southern end of Ivy Street and 20th Street (Section 9, Township 31 North, Range 1 West) at the top of Basin 18. The City of Port Townsend installed 1,200 linear feet of 12 inch water main from the High Zone Reservoir which connects to an existing 8 inch water line located in Ivy Street in200412005. The line crossed a wetland that was not mapped on the City of Port Townsend Environmentally Sensitive Area Map (Wetlands). This wetland is a depressional/sloped Category II wetland that collects upslope stormwater and terminates downslope in man-made ponds. This wetland includes a matrix of undisturbed and diverse plant community within second growth and mature forests. Prior to the construction and installation of the water main this wetland was delineated and categorized (Olympic Wetland Resources,Inc., July 15,2004). Mitigation requirements were prepared to meet the standards outlined in the Department of Ecology, Guidance on Wetland Mitigation in the State of Washington State (April 2004) and City of Port Townsend's Environmentally Sensitive Areas (ESA) Ordinance (Chapter 19.05 PrMC). 1.1 Project Goals and Objectives The primary goal for this project is to compensate for unavoidable wetland impacts from construction and installation of the water main. Wetland loss has been compensated at a replacement ratio of 2:1. The wetland, buffers, and construction pathways were revegetated with appropriate native species to increase overall functions, values, and site diversity. There were 4,500 square feet of impact within the wetland/buffer and 13,200 square feet of impact within the remaining construction zone. Olympic Wetland Resources Ivy Street Final Monitoring Report Page 1 July 2009 Environmental objectives are to enhance the structural and biological diversity of the site and to further protect the water quality of the wetland by upgrading the buffers through the revegetation plan. Additional goals are to control non-indigenous plant species along the revegetated areas, and to document the success of the project through monitoring. The goal of monitoring is to determine whether the performance standards identified in the plan have been met. Primary performance standards require survivorship of 80% or more of all planted species after the five-year monitoring period. Overall plant cover is assessed during the monitoring process thereby including planted species, desirable volunteer species, and invasive weed species. A project is considered successful if the desirable plant cover is greater than 80% and weed species cover is less than l5Yo atthe end ofthe five years. 1.2 Planting and Maintenance All plants were inspected prior to installation and were healthy and vigorous. Eric Page (City of Port Townsend Project Manager), Dixie Llewellin (OWR), and Joe Babboni (Dirt and Stuff Construction) distributed the potted specimens according to the plan. Dirt and StuffGeneral Contractors installed all plants April2005. Plants were installed and then mulched with a 4 to 6 inch deep layer of bark 3 to 5 feet around each individual plant. City compost was added to each planting hole. A drip irrigation system was then installed with lines to each individual plant. Joe Babboni maintained the watering system and weeded the site through 2006; continued maintenance was then contracted by the City through 2007. 2.0 Monitoring Methodology Monitoring methodology includes counting individual trees, shrubs, and emergents to determine plant survivorship, habitat density, and general condition of planted species. Treeso shrubs, and herbaceous plants were planted in well-defined plant communities and zones according to water tolerance. The revegetated site is within a linear strip and small enough that individual plants could be counted. Actual survival percentages were calculated by comparing numbers of plants observed against total numbers planted. 2.1 Determining Sulival Rates Using Monitoring Forms A monitoring form included in the Appendix (Figure I) identifies survivorship of planted species Quantitative data gathered using the monitoring form helps determine the survival rate of tree and shrub species. This information will determine whether plant survivorship is suffrcient to meet the performance standards specified in the plan. Since this site has a high number of volunteer native species the overall percent cover is also counted. 2. 2 Documenting Wetland Changes Using Photographs Seven permanent photopoints have been established to document the changes of the vegetation layer over time. Over the course of the 5-year monitoring program, the growth and development Olympic Wetland Resources Ivy Street Final Monitoring Report Page2 July 2009 of the plant communities should be discemible in the series of photographs. Photopoint locations are indicated on the Photopoint Location Map in the Appendix (Figure II). Photographs from all photopoints are included in the Appendix (Figures III and IV). 3.0 Monitoring Schedule A five-year monitoring period is required to evaluate the overall success of the project and to determine success rates of planted species. Monitoring has been conducted during the growing season (June or July) and has continued annually for the last 5 years. The Monitoring and Maintenance Schedule is outlined in Table 1. below. Table 1.and Maintenance Schedule 4.0 Results and Discussion 4.1 Survival Rate for Planted Species The total survival rate for trees and shrubs is 83% (294 plants planted in 2005, with232 plants alive in 2009). Within the planted tree layer, red cedars are well adapted to moist and shady conditions and are therefore thriving (88% survival). Several vine maples did not survive the initial planting. The remaining vine maples are generally well established and healthy, especially the plants that have grown tall enough to compete with surrounding vegetation and are out of the reach of grazers (66% survival). The shrub layer within the wetland is especially vigorous and planted species are creating a dense continuous layer. The red-osier dogwood have been grazed by deer but are still vigorous with only a small decline in numbers from last year (600/o survival). Both twinberry (100% survival) and ninebark(90% survival) had very good survival rates; they are both over 5' tall and are producing seeds and forming a dense under story. The upland shrub layer has a good survival rate since they are partially shaded by the surrounding mature forest. The shade from these trees prevents excessive heat during our dry summer Olympic Wetland Resources Ivy Street Final Monitoring Report FallSpringFallSpringFallSpringSpringFallSpringFall 2009200720072008200820092005200520062006Maintenance XPlanting X N/AxXxxXMaintenance x x x XIrrigation no noReplace plants as needed Monitoring x xxxxVegetation and Habitat x x xxxPhotopointsxxxxxAnnual Report Page 3 July 2009 months. Survival rate for the red flowering currant is moderate since it grows slowly, is grazed by deer, and if often out-competed by other vegetation; only 9 of the original 15 plants were observed (60% survival). The hazelnut and Indian plum showed no mortality (100% survival) and are shrubs from 4 to 6 feet tall. Although salal is easily covered by other plants there were at least 90 plants present out ofthe 108 planted (83% survival). The exact count for salal is difficult due to the volunteer plants from the healthy and expanding salal hedge adjacent to this linear revegetation proj ect. 4.2 Volunteer Species Initial construction passed through a native forest where there were few invasive species present. The native trees and shrubs along the path of the pipeline are quickly returning to the site. Red alders, Scouler's willow, thimbleberry, salal, bald hip rose, elderberry, coltsfoot, oceanspray, and the native trailing blackberry are filling in the upland areas of the mitigation project. Within the wetland, water parsley, sedges, and rushes contribute to the dense herbaceous layer. 4.3 Weedy Species Weedy species or non-native species that would be a problem for native plant reestablishment are sparse and consist of a very small population of bull thistle. The thistle could spread but will most likely be shaded out by the trees and shrubs. During this final monitoring in 2009 the weedy species represent far less than 5o/o of the overall cover. The performance standards requiring l1Yo or less aerial plant cover of weedy species has been clearly met. 4.4 Maintenance and Watering Joe Babboni of Dirt and Stuff Construction weeded and maintained the irrigation system through 2006. Further maintenance was conducted by contract labor in 2007. All native trees and shrubs no longer require irrigation. 5.0 Summary This report presents data from the final year of the five-year monitoring period for the Ivy Street High Zone Water Main Project as required by the City of Port Townsend Public Works. The final evaluation all original Project Goals and Objective and Performance Standards of the project have been met as outlined below. Project Goals and Objectiveso to revegetate the wetland buffers and designated areas along the disturbance caused by the installation of the Ivy Street High Zone Water Main;o increase diversity of plant species with appropriate native trees and shrubs;o to remove or control non-indigenous plant species along the newly revegetated areas;o to guarantee the success of the project through maintenance and irrigation of planted species (guarantee either City crew time or contracted labor); ando to document the success of the project through monitoring (annual monitoring reports for 5 years). Olympic Wetland Resources Ivy Sheet Final Monitoring Report Page 4 July 2009 Performance Standards The proposed length of time for mitigation compliance is five years. This time period will allow for the planted and volunteer species to become established. Survivorship of tree and shrub species is expected to be 80% or greater and will be determined during the monitoring process. The wetland buffer mitigation is considered successful if 80% or greater of desirable cover is achieved, and the plants are healthy and vigorous and there is less than l5Yo atthe end of the five years.o Survivorship of tree and shrub species is 83% as documented in this 2009 report. o The overall aerial native plant cover during the fifth years is around 90% when including volunteer species, which exceeds the requirement of at least 80% natives; o Weed populations are less than approximately 5%o of aetial cover; The success of this project is due in part to the careful plant installation, ongoing maintenance, and monitored inigation system. This project could serve as a model for future mitigation projects. I appreciate the opportunity to work with the City engineers and staff during the duration of this proj ect. Sincerely, Dixie Llewellin Principal Biologist, Olympic Wetland Resources. Certified for Wetland Delineation,l9ST Manual Wetland Training Institute, June 1995, Certified for Wetland Rating DOE' 2007 Olympic Wetland Resources Ivy Street Final Monitoring Report Page 5 July 2009 Appendix Figure I. Monitoring Form Figure II. Photopoint Locations Figure III. PhotoPoints 1-3 Figure IV. PhotoPoint 4-7 Figure l. Monitoring FormIvy Street High Zone Water Main Connection Project71U2009Species NameCommon NameCommentsTotals294 274 252 246 238 232 830hVolunteer native species include:Alder, scouler's willow, thimbleberry, salal, baldhip rose, oceanspray, trailing blackberry, elderberry, coltsfoot, water parsley, common rush,lady fern, nettles, bracken fem, horsetail, veronica.Volunteer non-native species include:Bull thistle (very few plants), giant vetch, pasture grasses.Percent coverage of invasive non native species: Much less than 5olo of overall coverrt?eGIq,G!c)Ig\otlioeoGIFrcGIo\o6l6al0)6acgaMany plants grazed by deerVery healty and establishedNative populations mergingHealthy, up to 6'highEstablished, up to 5 feet highHealthy dense shrubsDoes best in open areasEstablished, up to 8'in heightMost are healthy, grazing seen100%83%t00%1000/T.90%60%88%66%60%9942213089085I9449I3689085I99t2452t3889085I472l4489585I95810585I0I94727455I105I4832508r088SalalTwinberryIndian plumNinebarkRed-flowering curraRed cedarVine mapleRed osier dogwoodHazelnutCorylus cornutaGaultheria shallonLonicera involucrataOlemeria cerasiformisPhysocarpus capitatusRibes sanguineumThuja plicatoAcer circinatumCornus stolonifera4105410541054t054la54105410541054105Vine maples and red-flowering currants had high mortality after initial planting in 2005 Ttdt' Photopoint Locations Mitigation and Revegetation Plan Ivy Street High Zone WaterMain Scale: l" = 50'Wetland Resources, 855 50th Sheet Pod Torunsen4 WA 98358 Date: July 2009 360 3E5-6432 dixie@cablespeed.com Clienr City of Port Townsend 181 Quincy Street Port Townsend, WA 98368 |ob #: 2008-07020 Figure il Photopoint #1 Install 12" culvert at2o above level Wetland Continues Downslope Upland Species Vine maple, Red-flowering current Mid Zone Species Hazelnut, Red Salal swale Wetland Species Ninebark, #4 Delineated Photopoint #7 Path of Construction (-13,200 Sq. Feet) Mitigation and Revegetation Areas Wetland and Buffer Impacted (-4,500 Sq. Feet) q?r00' Photopoint #5 Figure III. Photopoint #2 Photopoint #2 Photopoint #l Ivy Street High Zone Water Main Project Final Monitoring2009 Photopoints 1-3 July 2009 Olympic Wetland Resources, lnc. Photopoint #3 Figure III. Figure IV. Photopoint #4 Photopoint #6 Ivy Street High Zone Water Main Project Final Monitoring2009 Photopoirxs 4-7 July 2009 Photopoint #5 0lympic Wetland Resources, lnc. Photopoint #7 Figure IV.