Loading...
HomeMy WebLinkAboutWetland Mitigation Addendum 995600015Steve Cross Addendum to Buffer Reduction Report And Revegetation Plan Parcel # 995-600-015 September 2004 Contents Introduction Buffer Reduction Plan Buffer Protection Stormwater Control Fencing Revegetation Plan Summary Appendix Sheet # 1 Buffer Reduction Map Sheet #2 Planting Plan Table # 1 Plant List and Landscape Specifications Table #2 Re-seeding Recommendation and Quantities Installation Specification and Recommendations - - - ~ .: ~ ,~ "' ~ : _ ... ..`~ f i i ~ - }}s ~ q ~i `•k ~i { i~ ` - ~~ 'lk l 1 l t (t.k 1~ ~ S Y '._i: j ~ i ' j ~ 3 .i ~' ,' i ; Y _a t ~j .. i i 1 [ t4._ i ~ I i t f~7 i { ~ij;t.~.tii t ~~ sr r, Steve Cross Addendum to Buffer Reduction and Revegetation Plan Parcel # 995-600-015 September 2004 Introduction This report has been prepared for Steve Cross as part of apre-purchase feasibility study to define a building site on the subject parcel, Lot 15 between Argyle Lane and the Port Ludlow Golf Course, in Port Ludlow, Washington. The entire parcel falls within the 100-foot buffer of a Class II Wetland and associated stream as outlined in the Bob Harrington Wetland Delineation Report (Olympic Wetland Resources, Inc (OWR), November 2003). A previous buffer reduction plan was prepared (OWR, January 2004) but a required setback of 50 to 60 feet from the Port Ludlow Golf Course was not included. This report addresses the Golf Course setback and includes a revegetation plan as required by a buffer reduction. Buffer Reduction Plan In order to accommodate a feasible building site, this project will require the reduction of the standard 100-foot buffer by more than the allowable 25% (Section 3.6.9 (6) Reducing Buffer Widths). Goals for this project are to define a building area with the least degradation or impacts to the wetland buffers and to specify native species in the revegetation plan, which will eventually restore original buffer functions and values. During a meeting with Steve Cross on September 3, 2004 proposed building plans and site locations were reviewed. The proposed structure, including construction impacts, will fall within 25 feet of the delineated wetland edge. The proposed house size, without the garage, is approximately 1800 square feet. Neighboring houses range from 1700 square feet to 2600 square feet (not including garages which average an additional 500 square feet). The projects will be built on the southern edge of the site, as far away from the wetland edge as possible. Impacts will still be within 25 feet of the wetland edge. Buffer reduction will be applied to allow the applicant to build a modest single-family residence within Lot 15. Please refer to the enclosed map for a potential building site location (Appendix, Sheet #1, Potential Building Envelope). Buffer Protection Vegetation should only be removed in the area specifically required for the building footprint and driveway. The area to be cleared must be clearly marked before any site clearing begins. Machinery will remain within the marked boundaries. Presently this site consists of a high diversity of mature native vegetation (22 species). No additional vegetation within the remaining buffer will be removed; the preservation of all Addendum to Buffer Reduction and Planting Plan 1 Olympic Wetland Resources, Inc September 2004 existing large trees and shrubs in the buffer is critical. Exceptions may include the small and dead standing alders under the canopy of the evergreen trees along the golf course right-of -way. In order to assess the site impacts from future construction, these alders were marked with orange flagging during a site visit on September 8, 2004, at the request of Steve Cross. Removal of the alders will be executed with minimal impacts to surrounding shrubs and no machinery will be used in this location. Stormwater Control All storm water from the construction project and finished home site will be directed away from the wetland. Sediment or runoff from the project should be minimized with the use of straw bales or sediment fences. This will be required during the entire building process and will continue to be required until the vegetation becomes established and can act as a natural filter. A gravel base will be placed on driveways and parking areas. Fencing A permanent physical barrier will be installed between the driveway/home site and the remaining wetland buffer. This fencing is critical to prevent further degradation to the wetland by future. owners and preserve remaining vegetation within the wetland buffer. Final-xeyegetatLOn of the site should not be conducted until the permanent fencing is installed. Fence sari con ist ofsplit rail fencing, logs, or formal fencing. The fence should be permanently maitrtairied. Revegetation Plan t The primary goal of this revegetation plan is to minimize further buffer imp~cts,by ~lattng y. native trees and shrubs, which can tolerate conditions found on this site. Sp~c~~~'s`~`ho`sen fQr ~_._ ~ " replanting are common to many landscape plans. Plantings may be rearranged to suit landscape and aesthetic choices after final home site and fencing are complete. Existing trees and shrubs should be protected during the construction and revegetation process. Secondary goals for this plan include revegetation of the site to increase species diversity, thereby increasing habitat value for wildlife. The impacted area for a home site and a driveway is approximately 3,700 square feet (40' X 40', home construction zone, and 12' X 60' driveway). The planting plan includes enhancing areas adjacent to the driveway and to the perimeter of the construction site. The buffer required by the Port Ludlow Golf course will be planted with short native shrubs so the view is not impacted. Included in the Appendix is a planting plan with locations and numbers of each species to be planted (Sheet #2). Plants included in the revegetaion plan include vine maple, Sitka spruce, red cedar, hazelnut, red- flowering currant, and Oregon grape. Complete landscape specifications are listed including quantities, sizes, optimum locations, and spacing for each plant. All remaining bare areas should be re-seeded with the seed mix included in the Appendix (Table #1 and Table #2). Also included in the Appendix is a directory of local nurseries, which supply native plants. Proper installation procedures of newly planted species ensure higher survival rates. Revegetation requirements are outlined in more detail in the Appendix (Installation Specifications and Recommendations). It is critical to the success of any newly planted trees and Addendum to Buffer Reduction and Planting Plan 2 Olympic Wetland Resources, Inc September 2004 shrubs to be maintained for the first two to three years. Maintenance includes watering and weeding and replacement of plant material that does not survive after the initial planting. Summary The subject parcel (Lot 15) owned by Bob Harrington and under pre-purchase feasibility study by Steve Cross is completely within the boundaries of a Class II wetland buffer (100 feet). The site has been delineated and a buffer reduction plan has been prepared (OWR November 2003, and January 2004). Other setbacks for the site include a 50 to 60 foot setback from the golf course. This report is an addendum to the above reports and includes the required revegetation plan. To accommodate a modest single-family residence (approximately 1800 square feet, excluding .garage} buffers will need to be reduced to 25 feet in some locations. To mitigate impacts all building will be located as far from the wetlands as possible, a fence will be installed, and the enclosed revegetation plan will be implemented. Boundaries of house and driveway footprint will be clearly marked prior to commencement of clearing, in order to avoid further impacts to the reduced buffer. Impacts are estimated to be 3700 square feet. Mitigation strategies include revegetating the site with over 90 native trees and shrubs. These plants will be installed after the permanent fence and final construction is complete. The success of this project will be dependent on ongoing maintenance. Final inspection should include compliance with the mitigation plan and should follow the installation of the fence and all native vegetation. Final determination of buffer reduction and building site approval will be by the Jefferson County Department of Community Development, Critical Areas Division. If I can be of further assistance, please don't hesitate to call. 1' /? f~ e ! ~~~ Dixie Llewellin, Principal Biologist Olympic Wetland Resources, Inc. _ ._ ..-~ ~ ~ 1987 Corps of Engineer Manual Certified for Wetland Delineation - q~.=~__Y~ y t ~ ~~ ` ~~~ , --- S {{ June 1995 Wetland Training Institute ~-_s. ~" ~ `; t ~~ t } t •; , g _ ; F. ' 1 i ~} .1 Addendum to Buffer Reduction and Planting Plan 3 Olympic Wetland Resources, Inc September 2004 Appendix Sheet #1 Buffer Reduction Map Sheet #2 Planting Plan Table # 1 Plant List and Landscape Specifications Table #2 Re-seeding Recommendation and Quantities Installation Specification and Recommendations ~' ~`' ~' ,v------t ~~~ ~~ ~ ~`~jEFFEi;S~J;~ ;OUNTY DEPZ. OF CO$~~~~~UNi(Y pE\iE~OPMEN7 ~, rrfle: potential Building Envelope Scale: Sheet - ~~y ~ Olympic Wetland Resources, Inc. and Findings Map As Indicated ~' "' `~ Parcel #995-600-015 ' ~ ~~ ~~~ 85650th Stmt # 1 ~~'' =~ September 2004 <..~= Port Townsend, WA 983b8 (~ie~: Steve Cross ``f' 3b0 385-6432 1oh #: ~I '`~ 6523 California Ave SW # 199 2004-7676 j~ Seattle, WA 9$126 :.~ S~ G :~l rrtle: Planting Plan Scale: Sheet >;~., As Indicated - ~-t_~~ Olympic Wetland Resources, Inc. '" ~' ~~~~ " Parcel #995-600-O15 ~`'~~ `~~ 856 50th Street #2 ~`' ~~ September 2004 `~ ., }t; Port Townsend, WA 48368 [Prent: Steve Cross i ,,~. ~~' 360 385-6432 Job #: 6523 California Ave SW # 199 2004-7676 I` Seattle, WA 9$126 7 0 0 U 15 ,~ ~o„< ~, 'i:; y , i ~ -~--- ~~ _s. ` 4 - t Driveway (12') N ---25' ~ 'r. ~ ~ ~ ~~ F~~tential Building... ~~ Envelope ~r \\,'/Wetland Ede ' . .. ~~~ 1 fi ^ry 4 'J ~~~ ~ ~ ~ ~ tv t TT o T a ~'uie 1\faple (10) Sitla Spivee (8) Hazelnut (10) ~ Red Cedar (8) DogROOd(15) Red-flowering n `i}' Oregon Grmpe (20) Cuirant(20) Golf Course Setback Native plants chosen for this plan are offen used in landscape settings. Actual configuration of plants can be rearranged after final homesite consturction and fencing are complete. Table 1. Wetland Plant List and Landscape Specifications Scientific Name Common Nance USFWS Loacation Condition Size Sppcng Quantity Rating Trees Acer circinatum Vine maple FACU shade container 2-Sgal 6' 10 Picea sitchensis Sitka spruce FAC shade container 2-Sgal 10' 8 Thuja plicata Cedar FAC shade container 2-Sgal 10' 8 Total 26 Shrub Berberis nervosa Dull Oregon grape FACU sunny container 1 gal 2' 20 Corms sericea Red-osier dogwood FAC sunny container 2ga1 4' 15 Corylus cornuta Hazelnut FACU shade container 2ga1 4' 10 Ribes sanguineum Red-flowering Curran FACU sunny container 1-2ga1 5' 20 Total 65 Legend Scierititic and Common names: Scientific name according to Hitchcock and Conquist (1976) Flora of the Pacific Northwest USFWS Rating: OBL Obligate wetland plants almost always found in wetland (99%), FACW Facultative wetland plants usually in wetlands (67-99%) FAC Facultative wetland plants usually in wetlands but occasionally in uplands (34-66%) Location: Plant location on site, also refer to planting plan for clarification. Condition: As available from nurseries. Size: As typically planted for restoration projects. Spacing: Recommended spacings. Quantity: Total number of plants for project. Table 2. Re-seeding Recommendations and Quantities Scientific Name Common Name Percent Festuca rubs var. commutata Red fescue 40% Dechampsia cespitosa Tufted hair rass 30% Lolium multiflorum Annual a rass 20% Trifolium hybridum Alsike clover 10% Planting recommendations: 25 lb. per acre Native Plant Nurseries Fourth Corner Nurseries, 3057 E. Bakerview Road Bellingham WA 98226 (360) 734-0079 Shore Road Nursery, 616 Shore Road Port Angeles, WA 98362 (360) 457-8482 Sound Native Plants, P.O. Box 7505, Olympia, WA 98507 (360) 943-7026 Woodbrook Nursery, 1620 59th Ave. Gig Harbor WA 98335 (206) 265-6271 ~- +: - ~-~ r .;~ + ~r I ~ ~; f x.~~ -- -- i I ~ .,ski f r r ~_ ll ~~ , u: Cross Revegetation Plan Olympic Wetland Resources, Inc. Installation Specifications and Recommendations Fall Installation Planting should be installed between mid-September and mid-November, unless the new plantings can be watered throughout the summer. Plantings installed in the fall generally outperform those installed in the late winter or spring. Plants put in the ground in the fall have the advantage of an extended period for root growth before rapid top growth in the spring. In the fall, the soil is warmer and more aerated than in the spring and most plants experience active root growth during this time. The cool, cloudy days and frequent precipitation of fall and winter also provide ideal transplanting conditions. Until sufficient root systems develop, newly installed plants will undergo transplanting stress that can be exacerbated by hot sunny days. Fall and winter weather allows for reduced transpiration and provides ample moisture for the roots while the plant recovers from transplant shock. Root Disturbance Immediately before installation plants with broken, damaged, or twisted roots must be pruned. Matted or circling roots of containerized plantings must be pruned or straightened and the sides of the root ball must be roughened from top to bottom to a depth of approximately half an inch in two to four places. If circling roots are left, they may eventually girdle the plant as they grow and thicken in place. If the roots at the edge of the root ball are straightened and extended, they will have access to a greater volume of soil in the planting hole. Also, the roughened edges of the root ball will have better contact with the backfill soil. Disturbing and removing one-fourth to one-half of the roots in the outer inch of the root ball will damage only the most sensitive plants; most often, this treatment actually stimulates increased plant growth. Plant Depth The finished height of each plant's root ball will be slightly higher than that of the surrounding soil. The exception is for sandy soils, in which case the soil heights will be even. The top of the root ball will not be covered with backfill soil. A watering basin will be formed around each planting by building a berm of soil at least 34 inches in diameter. When planting acontainer-grown plant, the top of the root ball should not be covered with any other soil. Covering the root ball with soil, particularly if it has a finer texture than the potting or field-growing soil, will generally cause water to flow around the root ball instead of into it; root balls covered in this way may "- ~ ~ T° receive water only from below. To allow direct wetting of the root ball from ', ; ` ;~~ {~~ ' 1- ~~i C~=~:` ~` ~;i.~ ~ ~- 1 ~~ above, install the plant so that the top of the nursery soil is slightly higher than the surrounding soil level. If the soil is sandy, or of a large particle size, then the nursery soil should be level with the surrounding soil. A watering basin made of mounded soil around each planting will further help to catch water from above-the berm should be at least 30 inches in diameter surrounding a plant. Mulch placed within the basin and on the berm will limit moisture loss from the root ball and surrounding soil, but take care that it does not come into contact with the stem of the plant as rodents or pathogens living in the mulch may attack the bark. Maintenance: Weeding and Irrigation The use of appropriate native species and careful planting ensures that the need for ongoing maintenance will be minimized. However, some maintenance is required to ensure that the young plants become established. It is recommended that weeding around new plants be conducted once or twice a year during the months of May and September for the first five years, and as often as needed after that. All Scot's broom, Himalayan blackberry, and thistle should be monitored and eliminated from the site. Irrigation may be required for upland species (vine maple and red-flowering currant) for the first three years or until plants are well established. Hand watering or irrigating with overhead sprinklers once a week should be adequate during the hot summer months. 2