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HomeMy WebLinkAboutHMP - HMP Habitat Managment Plan - 10/21/2021 P LA N N I f\lt Habitat Management Plan Parcel# 32127-53-00207 422 E Olde Lyme Rd RECEIVED Shelton, WA 98584 OCT 2 1 2021 Mason County 615 W. Alder Street Report prepared for: Fredrick Rose PO Box 284 Spanaway, Washington 98387 Prepared by: Rob Nagel 680 E Philura Ln Shelton, WA 98584 arctosaerial@gmail.com (425) 344-9315 (360) 229-3118 ARCTOS AERIAL Environmental Consultation I Drone Imagery Project: 2021-H M P-009 August 2021 A RCTOS Project: 2021-HMP-009 August 2021 AERI A L Table of Contents Overview................................................................................................................1 PropertyDescription..............................................................................................2 Analysis of Potential Impacts.................................................................................3 MitigationMeasures..............................................................................................4 Monitoring ...........................................................................................................10 Summary..............................................................................................................10 References............................................................................................................12 List of Figures Figure1: Vicinity Map ............................................................................................2 Figure 2: Map depicting parcel & buffers...............................................................3 Figure3: Site Plan...................................................................................................9 ARCTOS Project: 2021-H M P-009 August 2021 AERIAL Habitat Management Plan 32127-53-00207 422 E Olde Lyme Rd Shelton, WA 98584 Overview This report details a Habitat Management Plan (HMP) for the above referenced property in Mason County, Washington. The purpose of this report is to address potential adverse impacts from the construction of a proposed Single-Family Residence (SFR) within the buffer of Cranberry Creek, a fish-bearing tributary to Case Inlet and designated Shoreline of the State of Washington. Mason County requires a 150-foot buffer with an additional 15-foot building setback, which encompasses the entire parcel. The SFR (1,092ft2) is proposed 50-feet from the ordinary high-water mark (OHWM) of the stream. Mitigation measures have been designed to offset the potential impacts of constructing the SFR on the ecological functions and fish and wildlife habitat of the stream buffer. Measures include Enhancing 1,100ft2 of stream buffer in the area between the structure and the OHWM of the stream for a mitigation ratio of 1:1. The objectives of this report are as follows: • Identify potential impacts of the construction of the proposed structure within the stream buffer on the buffer's ecological functions and fish and wildlife habitat. • Determine mitigation measures that would offset those impacts and result in no-net-loss to ecological functions and fish and wildlife habitat within the remaining buffer. 1 Project: 2021-HMP-009 August 2021 ARMS AERIAL Mason County WAGIS FA- © ►y i. ' SIfOMOYISN VA!!EY J �. 'YCE MEN ORA lAViE O ,I Ern.11ERE,G rmm.F10,NG-- - U1 Figure 1:Vicinity mop of project. i Property Description & Project Background The parcel is 0.20 acres in size and located in the SW% of the SE% of section 27, Township 21 North, Range 3 West. The site currently has a few mature Douglas fir, western red cedar, and big-leaf maple. There is virtually no understory except invasive English ivy. An approved septic system already exists on the lot. Mason County requires a 150ft buffer with an additional 15ft structure setback, which encompasses the entire subject property. This lot was established before the effective date of the Mason County Resource Ordinance and the Shoreline Master Program. Without a Shoreline Variance, the property owner lacks a reasonable use of the lot. 2 Project: 2021-HMP-009 August 2021 A RCTOSAERIAL Figure 2:Map showing Cranberry Creek,the regulated 150'buffer as the solid green line and the 165'structure setback as the dashed green line.The red polygon is the parcel in question. Analysis of Potential Impacts Vegetated buffers serve an important role in protecting critical public resources, as well as fish and wildlife habitat from adverse impacts associated with development. Below are the potential adverse impacts to ecological functions associated with the construction of this proposed structure within the lake buffer. - Increased storm-water runoff and erosion Impervious surfaces such as roofs and driveways contribute to increased flow of runoff during storm events. This increased flow could contribute to erosion and increased sediment reaching the lake without a proper storm water management plan. The proposed building site is limited to 1,092ft2 and no significant increase in storm-water runoff is anticipated. 3 A RCTOS Project: 2021-HMP-009 August 2021 AERIAL - Loss of wildlife habitat The development footprint of this structure within the buffer is limited to 1,092ft2 for the SFR. Mitigation measures, including large-woody debris placement and native plantings, will increase the amount of wildlife habitat adjacent to the development site and increase the species richness and structural diversity of the remaining riparian area. - Increased disturbance from noise pollution A temporary increase in noise from construction activities is likely to occur. but activities will be limited to daylight hours, and the project is located in an area of the shoreline where human noises are a common occurrence. Also, no known nesting sites or individual occurrences of priority habitats and species have been identified near the project site. - Increased Solar input The proposed structure is sited on the east side of the stream and most of the property's mature trees will remain. No increase in solar input to the stream is expected. Mitigation Measures To avoid, minimize, and mitigate for the potential adverse impacts identified above, the following have been identified as appropriate measures for this project: - Minimizing/avoiding impact The proposed project minimizes the impact to the stream buffer by minimizing the size of the SFR to ±1,092ft' and placing the structure as far from the stream as feasible, at 50'. There is not enough room to fit the structure any farther from the stream because of the narrow shape of the lot, the lot line setbacks, and the septic tank and drain-field setbacks. 4 ARCTOS Project: 2021-HMP-009 August 2021 AERIAL. - Best Management Practices for construction Construction activities related to this project will be restricted to favorable weather conditions and best management practices for reducing disturbance and erosion will be followed, including placing straw over exposed areas, and erecting silt fencing below the project area. Equipment will be checked daily for leaks and all fuel, lubricant, and chemicals will be stored outside the shoreline buffer. - Clustering of development All activities related to this project will be clustered to the extent possible without impacting more of the shoreline buffer than necessary. Equipment and materials will be parked/stored outside the shoreline buffer when possible. - Removal of invasive species All occurrences of noxious weed species observed in the vicinity of the project site and mitigation areas will be mechanically removed without the use of chemical herbicides, including the English ivy observed near the streams edge, which is a class C noxious weed in Washington State. - Shoreline buffer enhancement & re-vegetation A mitigation area of 1,100ftz immediately adjacent to the stream's ordinary high-water mark (OHWM), will be enhanced by removing all occurrences of invasive English ivy and re-establishing native trees, shrubs, and ferns/groundcovers. The mitigation area will be enhanced further by selectively placing large-woody debris (LWD) within the mitigation area to add structural diversity and habitat for wildlife. The LWD will consist of at least eight logs 10-15ft long and >_10 inches in diameter. Additionally, any landscaping within the lot area is encouraged to consist of native plant species typically found in undisturbed riparian areas. Species selected should include common shoreline vegetation not currently on the property which will result in a net increase in species richness and biodiversity within the buffer. 5 A RCTOS Project: 2021-HMP-009 August 2021 AERIAL The minimum number of native trees, shrubs, and ferns/groundcovers to be planted in the mitigation area to meet the prescribed densities are as follows: -Trees = 11 (can be zero if an additional 30 shrubs are added) -Shrubs = 24 -Ferns/groundcovers = 35 Planting Guidelines for the Mitigation Area (adapted from Appendix C of the Mason County Resource Ordinance) Earthwork Machinery earthwork will be restricted to the minimum necessary in order to implement this plan; planting holes for specified vegetation installation will be hand dug. Native Plantings Native plantings will be installed within the mitigation area parallel to the edge of the buffer to achieve the following minimum densities: Trees — 10' on center Shrubs — 5' on center Ferns, grasses, and ground-covers —4' on center The plan calls for installing single trees, or clusters of three shrubs, on 10ft centers and single shrubs on 5ft centers. Areas between will be filled in with ferns, grasses, or ground-covers on 4ft centers. The entire mitigation area should be mulched to prevent any non-native species from establishing within the mitigation area. Exact placement of installed materials will be up to the landscape installer, following the basic 10-foot spacing pattern described above and using the planting map as a guide. Successful implementation of the planting plan will achieve a structurally and biologically diverse plant community that mimics undisturbed shoreline buffers. Volunteer native vegetation can be counted towards the target densities of restoration area at the time of monitoring audits. 6 ARMS Project: 2021-H M P-009 August 2021 AERIAL Native plant species appropriate for this area include, but are not limited to the following: Trees: Western red cedar (Thuja plicata) Douglas fir (Pseudotsuga menziesii) Garry oak (Quercus garryona) Western hemlock (Tsuga heterophylla) Grand fir (Abies grandis) Cascara (Rhamnus purshiona) Cottonwood (Populus balsamifera) Shore pine (Pinus contorta v. contorta) Pacific crabapple (Molus fusca) Serviceberry (Almenlanchier alnifolia) Shrubs: Ocean spray (Holodiscus discolor) Wax myrtle (Myrica californica) Thimbleberry (Rubus parviflorus) Hookers willow (Salix h000keriana) Tall Oregon grape (Mahonio aquifolium) Nootka rose (Rosa nutkano) Salmonberry (Rubus spectabilis) Salal (Gaultheria shallon) Evergreen huckleberry (Vaccinium ovotum) Snowberry (Symphorocarpus albus) Elderberry (Sambucus racemosa) Red osier dogwood (Cornus stolonifera) Ferns, grasses, and ground-covers: Sword fern (Polystichum munitum) Bracken fern (Pteridium aquilinum) Tufted hairgrass (Deschampsia cespitosa) Coastal strawberry (Fragaria chiloensis) Seashore saltgrass (Distichlis spicata) Coastal lupine (Lupinus littoralis) Silverweed (Potentilla pacifica) A RCTOS Project: 2021-HM P-009 August 2021 A E R I A L Twinberry (Lonicera involucrate) Henderson's checker-mallow (Sidalcea herdersonii) All planting should occur during winter dormancy. The optimum time for planting is from February to March. Installation Installation of the prescribed vegetation will be performed by qualified landscapers familiar with planting of native vegetation in natural settings. Installation will be performed only after construction on the property is completed to avoid damage to the plantings. Fertilizing Due to the proximity of the mitigation area to Cranberry Creek, NO fertilizer will be used during plant installation or maintenance. Maintenance Maintenance of the installations will be the responsibility of the landscape installer. Maintenance is to include any weeding or watering necessary to ensure plant survival for up to three years after the date of installation. 8 A RCTOS Project: 2021-H M P-009 August 2021 AERIAL Monitoring Following the implementation of the mitigation measures, an annual report will be submitted to the county for 3 years post construction. The report will detail the presence of new, or the reoccurrence of any invasive species. Invasive species found on site will again be removed mechanically, using hand tools only to reduce disturbance to the shoreline buffer. The annual report will also document the planting success of the mitigation area. If planting survival in the mitigation area falls below 90% in the first three years after installation. The area will be re- planted to meet the target densities. If any failures of mitigation measures are identified during the annual inspection, corrective actions will be recommended in the report and will be taken by the property owner to restore them to working order as soon as possible. Summary This report Identifies potential impacts of the construction of a proposed 1,092ft2 SFR within the regulated buffer of Cranberry Creek. Mitigation measures have been proposed to avoid, minimize, and mitigate for those impacts on the Stream buffer's ecological functions and fish and wildlife habitat. Successful implementation of the proposed mitigation measures will result in a net benefit to the shoreline and its buffer's ecological functions, structural diversity, and species richness. Mitigation measures include enhancing 1,100ft2 of existing buffer through noxious weed removal, native plantings, and LWD placement for a mitigation ratio of 1:1. 10 ARMS Project: 2021-HMP-009 June 2021 AERIAL References Guard,J. (1995). Wetland Plants of Oregon &Washington. Lone Pine Publishing. 240 pp. Edmonton, Alberta, Canada. Pojar,J. and A. MacKinnon. 1994. Plants of the Pacific Northwest Coast (Revised Edition 2014). Lone Pine Publishing. 528 pp. Vancouver, British Columbia, Canada. WDFW. 2002. Integrated streambank protection guidelines. Washington Department of Fish and Wildlife, Washington Department of Transportation, and Washington Department of Ecology. Posted on Washington Department of Fish and Wildlife web site: https://wdfw.wa.gov/sites/defa u It/files/publications/00046/wdfw00046.pdf 11 ARMS Project: 2021-HMP-009 August 2021 AERIAL I XARCTOS AIRIAI r -187' Cranberry Creek � Environmental Consulting I Drone Imagery / Proposed Existing 191 PO Box 2466 Mitigation Area Septic Tanks Shelton, WA 98584 (1,100ft2) Existing (425) 344-9315 Drainfield arctosaerial@gmail.com I8� I www.arctosaerial.com N At r89 ,O O Ig / O OL0 9, Ln r J >Q j O N 189 / •> ry) O C Proposed SFR C w O 26'x42' L U N 00 OD 190 , Map created by: Rob Nagel October 7th, 2021 Revison: f� ti c' N 0 10 20 30 40 ft Scale: 1 " = 15' 9 Elevation Cross Section ARCTOS j 189AERIAL XF co, -�i / Environmental Consulting Drone Imagery �89 PO Box 2466 Shelton, WA 98584 jco, (425) 344-9315 arctosaerial@gmail.com www.arctosaerial.com 189 Proposed SFR CL 26'x42' (CC� CD(1,092ftz) G o � 00 p Lr) ' 00 1g0 O T >' �l � ` � � � J Q 0 y`b X > N m O O D +J j&GEIVED 189 OCT 21 2021 � ' �Al. A!d+er Street 200 .---------. ----- -—-—- Map created by: Rob Nagel 195 -————— October 7th, 2021 Revison: 190 —— 185 ___ ___r_ __ ___-__-_ -_ - Proposed Grade Current Grade 180 ------------------------------------------------------- N 0 10 20 30 40 ft 0 10 20 30 40 50 60 70 0 90 100 110 120 ft Scale: 1 " = 15'