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HomeMy WebLinkAbout2005.07.15 - Level Wetland Assessment for O'Meara Addition Lot 3I I ^LA/A Olympic Wefland Resources, Inc. Dixie Llewellin, Principal Biologist Jul:15,2005 Introduction As per request by Tom Burni, the 50 X 100 foot lot on 3ltt Street was evaluated on July 5, 2005 as part of a pre-purchase evaluation. The lot is adjacent to the North Deering Wetland. There has been no discernible change in the wetland edge since the delineation for the City of Port Townsend in October 1996 (Wetland Determination Report Wetland I.D. #5-4 North Deering Wetland, Polaris Engineering and Surveying, Inc. and Olympic Wetland Resources Inc.). At that time the wetland was rated as a Category II wetland; all Category II wetlands received 100-foot buffers. The entire lot falls within the wetland buffers. This wetland has been re-evaluated according Port Townsend's recently adopted code. According to the new system the wetland is still rated as a Class II Wetland (total score for wetland functions is 63 points). Under the current code buffers are assigned sizes according to levels of habit function. This wetland has a moderate level of function for habitat (25 points) and therefore is assigned a buffer of 150-feet when calculating for high impact development (Critical Areas-Wetlands 10.05 E. Buffers and Setbacks). The new rating form is included with this report. Buffers The intent of buffers is to protect important wildlife habitat and wetland features from the adverse impacts of adjacent land uses. The Port Townsend Environmentally Sensitive Areas Code, described below, defines development restrictions. Section 19.05 Wetlands E. Buffers and Setbacks. 8. Except as otherwise specified, buffer zones shall be retained in their natural condition. Where buffir disturbance has occurced during construction, or in violation of this chapter, revegetation with native vegetation will be required unless the directors approves a substitute vegetation with the same or better mitigation characteristics. Level I Wetland Assessment; Obayasi Report File Number 2005-9890 1 Olympic Wetland Resources, Inc 7/05 Findings and Recommendations This neighborhood has had many alterations of the wetland and buffer. Addie's Ditch was excavated in an attempt to drain the wetland, 3ltt Street crosses the wetland, and many houses have been built in the wetland buffer prior to the enforcement of the code. The existing buffer consists of a combination of dense shrubs in the area nearest the wetland. The remainder of the lot is non-native pasture grass (to the east). It is important to site the building envelope as close to the eastem lot line as possible. Consideration should be made to minimize the footprint of the house as much as possible. Best management practices should be observed during construction. Sediment or runoff from the project should be minimized with the use of straw bales or sediment fences. Stormwater from all impervious structures should be directed away from the wetland or filtered prior to entering the wetland buffer. After the construction is complete, native trees and shrubs should be planted to screen the house from the wetland. This will also add additional vegetation layers and increase vegetation density within the buffer. A list of appropriate species for the site is included at the end of this report. Sincerely, Dixie Llewellin Prinoipal Biologist, Olympic Wetland Resources, Inc. Certified for Wetland Delineation, 1987 Manual. Wetland Training Institute, June 1995. Level I Wetland Assessment; Obayasi Report File Number 2005-9890 2 Olympic Wetland Resources, Inc 7/05 , Wetland Rating Form-Western Washington 26 12 25 63 l=Score >70 ll=Score 5169 lll=Score30-50 lV=Score <30 lt Category based on SPECIAL CHARACTERISTICS of wetland from aboveFinal t-ll-X-Does not based on Functions provided by wetland choose the "hi hest" WL#5-4 City Port Location:Section: 3 Township:3ON Name of Rater: Dixie Llewellin Score for Water Quality Functions Score for Water Hydrologic Functions Score for Habitat Functions Total Score For Functions Range:1W Affiliation: Olvmoic Wetland Resources. lnc. Date of Site Visit July 5, 2005 Estuarine Natural Heritage Wetlind Bog Mature Forest Old Growth Forest Coastal Lagoon lnterdunal None of the Above Depressional X Riverine Lake-Fringe Slope Flats Freshwater Tidal DDe ressional and Flats Wetlands FUNCTIONS lndicators that wetland function to reduce flooding D3. Does the wetland have the to reduce floodi and erosion? D3. 1 Characteristics of surface water out of the wetland Wetland has no surface water outlet Wetland has an intermittently flowing, or highly constricted, outlet Wetland is flat and has no obvious outlet and/or is a smallditch Wetland has an unconstricted surface outlet 4 2 1 0 2 1 3 D3.2 Depth of storage during wet periods Estimate height of ponding above the bottom of outlet Marks of ponding are 3 ft or more above the surface The wetland is a headwater wetland Marks of ponding between 2 ft to < 3ft from the surface Marks are at leastO.5 to < 2 ft from surface Wetland is flat but has small depressions on the surface that trap water Marks of pondinq less than 0.5 ft D3.3 Contribution of wetland to storage in the water shed Estimate the ration of the area of upstream basin contributing surface water to the wetland to the area of the wetland itself. Wetland ls ln Basin 5 The area of the basin is less than 10 times the area of the wetlind The area of the basin is 10 to 100 times the area of the wetland The area of the basin is more than 100 times the area of the wetland Wetland in the FLATS class (basin=the wetland,.by definition) 7 5 5 3 1 0 5 3 0 5 6otalD3Add the ints in the boxes Itiplier Yes if the wetland is in a location in the watershed where flood storage, or reduction in water velocity, it provides helps protect downstream property and aquatic resources from or excessive and/or erosive flows. NO if the water coming into the wetland is controlled by a structure such as a flood gate, gate, flap valve, reservoir etc. OR you estimate that more than 90% of the water in the which of the following indicators of opportunity apply Wetland is in a headwater of a river or stream that has Wetland drains to a river or stream that has flooding problems flow into a river or stream that has flooding problems flooding problems Wetland has no outlet and impounds surface water that might otherwise Other Wetland is at the top of a basin that reduces downslope flooding NO multi ier is 1 uce is from groundwater is2mu 12 Total -Hydrologic Function Multiply and score from D3 by D4 Add score to table on a e1 DDe ressional and Flats Weflands D1. Does the wetland have the that water to water Wetland is a depression with no surface water ouflet Wetland has an intermittently flowing, or height constricted, ouflet Wetland has an unconstricted surface ouflet 1 1 D1.1 Characteristics of surface water out of the wetland: Wetland is flat and has no obvious ouflet and/or outlet is a ditch 2 YES NO , organic, or anoxlc. 4 D1.2 The Soil CLAY the surface is 4 5Wetland has persistent, ungrazed, vegetation>=g5% of area Wetland has persistent, ungrazed, vegetation>=112 of area Wetland has persistent, ungrazed, vegetation>=1/10 of area Area seasonally ponded is >112 total area of wefland Area seasonally ponded is >1/4 totalarea of wefland 5 3 1 0 1D 3 of persistent nd forestlor(vegetation shrub,emergent,): ts areathe theof thatwetland is atfor 2leastponded but outdries sometimemonths,during Do countnot areathe isthatyear E!*imate area theasponded.permanently average five ofout ten years. Wetland has u < 1110 of area D1.4 of ponding or inu Area seasonal is <1/4 totalarea of wetland otalfor Di Add the in the boxes above {3 2 , urban areas, golf courses are within 150, of wefland afYES know believeto thereyou are in of watersurface compollutantsgroundwater tng theinto thatwetland tdwou reduceotherwise water in orqualitylakes,streams,groundwater fromradient thedowng wetland.whNote ofich the cOnditions sources.thefollowingprovide thetn withiwetland n 150' Untreated stormwater discharges to wefland Tilled fields or orchards within 150' of wefland orstream culvert into wetla thatnd drainsdischarges residentialareas,developed areas, farmed roads orfields,clear cuts by groundwater high in phosphorus or nitrogenWetland is fed Other YES mu is2 NO mu isl Itiplier 2 Total -Water Quality Function M ultiply and score from Dl by D2 Add score to table on 1 26 I Habitat Functiohs-lndicators that the wetland functions to provide important habitat H1.l Does the wetland have the to provide habitat for many species? 4 Check the types of vegetation classes present (as defined by Cowardin) if the class covers more than 10o/o of the area of the wetland or 114 acre. _Aquatic BedX Emergent plants X Scrub/Shrub (areas where shrubs have >30% cover)X Forested (areas where trees have >30% cover)X Forested areas have 3 out of 5 strata (canopy, shrubs,ffine number of vegetation types that qualify. lf you have round 2 1 Permanently flooded or inundated Addie Ditch Seasonally flooded or inundated Occasionally flooded or inundated Saturated only nt the # of plant species in the Wetland that cover at least 10 ft2 Do not include reed canarygrass, purple loosestrife, Canadian thistle POINTS 3 2 1 2 2 POINTS 2 1 0 the types of water regimes (hydroperiods) within the wetland. The water ime has to stream or river or H1.2 Hydroperiods more than 1O9/o of the wetland or 1/4 acres to count. the wetland H1.3 >19 5to19 <5 or more types present $pes present types present Lake fringe wetland Freshwater tidal wetland 3 H1.4 lnterspersion of habitats lnterspersion of habitats between vegetation, unvegetated areas is high medium or low High= 3 points Moderate=2 points Low=1 point None=0 points 1 1 Check the habitat features that are present in the wetland, the # of checks is the # of pointsil targe, downed weedy debris within the wetland (.4" diameter and 6' long)X Standing snags (diameter at the boftom >4') in the wetland Under cut banks are present for at least 6.6 ft and/or overhanging vegetation extends 3.3 ft for 33 ft - Stable steep banks of fine material that might be used by beaver or muskratX At least 'l14 acre of thin-stemmed persistent vegetation or woody.branches in areas that are seasonally or permanently inundated (structure for egg-laying amphibians).X lnvasive plants cover less than 25o/o of the wetland area in each stratum of plants 14Total for H1. Potential for providing Habitat Add the points in the boxes above H2. Does the wetland have the habitat for many species? H2.1 Buffers Choose the description that best represents condition of buffer of wetland.The highest scoring criteria that applies to the wetland is to be used in the rating. 100m (330') of relative undisturbed vegetated areas, rocky areas, or open water >95% of circumference. 100m (330) of relative undisturbed vegetated areas, rocky areas, or open water >50% of circumference. 50m (170") of relative undisturbed vegetated areas, rocky areas, or open water >95% of circumference. 100m (330') of relative undisturbed vegetated areas, rocky areas, or open water >25% of circumference. 50m (170") of relative undisturbed vegetated areas, rocky areas, or open water >50% of circumference. lf buffer does not meet any of the criteria above No paved areas (except trails) or buildings within 25 m (80') of wetland >95% circumference. No paved areas or buildings within 50 m (80) of wetland >50% circumference. Xll:1"?i:il?t#:fl r" r,lo" 1o.o ry ror more rhan es% orrhe circumrerence Buffer does not meet anv of the above criteria 5 4 4 3 3 2 2 1 0 1 POINTS 3 H2.2 Gonidors and Connections H2.2.1 is the wetland part of a relatively undisturbed and unbroken vegetated corridor (riparian or upland) that is at least 150 ft wide, has at least 30% cover of shrubs, forest of native undisturbed prairie, that connects to estuaries, or other wetlands or undisturbed uplands that are at least 250 acres in size? YES = 4 points (go to H2.3) NO = go toH2.2.2 Connects to Cappy's H2.2.2 is the wetland part of a relatively undisturbed and unbroken vegetated corridor (riparian or upland) that is at least 50 ft wide, has at least 30% cover of shrubs, forest of native undisturbed prairie, that connects to estuaries, or other wetlands or undisturbed uplands that are at least 25 acres in size? OR a Lake-fringe wetland , if it does not have an undisturbed conidor as in the question above?yES = 2 points (go to H2.3) NO = go toH2.2.3 H2.2.3 ls the wetland Within 5 mil (8km) of a brackish or salt water estuary OR within 3 mi of a large field or pasture OR within 1 mile of a lake greater that 20 acres? YES =1 point 4 1 H2.3 Near or adiacent to other priority habitats listed by WDFW POINTSngWhich of the followi Old-growth forests habitats are within 330 ft (100m) of thewetland white oak Riparian Aspen Stands Cliffs Urban natural open space Estuary/Estuary-like Marine' Estuarine shorelines Mature forests Prairies 0 3 H2.4 Wetland Landscape Choose the one description of the landscape around the wetland that best fits POINTS There are at least 3 other wetland within 112 mile, and the connections between then are relatively undisturbed ( light grazing OK, but should NOT be bisected by paved roads or development 5 The wetland is Lake-fringe on a lake with little disturbance and there are 3 other lake-fringe wetlands within 1/2 mile 5 There are at least 3 wetland within 1/2 mile, BUT the connections between then are disturbed 3 The wetland is Lake-fringe on a lake with disturbance and there are 3 other lake-fringe wetlands within 1/2 mile 3 There is at least 1 wetland within 1/2 mile 2 there are no wetland within 1/2 mile 0 Total for H2. Opportunity for providing Habitat Add the points in the boxes above 11 25Total Score for Habitat Functions- Add points for Hl and H2 and record on Page 1 Table L. Wetland Plant List and Landscape SpecificationsScientific NnmeCommon NameUSFWS ConditionRatingSize Spacinglu'10'10'4',4',5'5'5'2-5gal2-5gal2-5saI2gaI2sal2eal2ealT-2galcontainercontainercontainercontainercontainercontatnercontarnercontainerFACT.ACUT.'ACUFACUFAC+FACUFAC+FACUDouglas'hawthomShore pineI)ouglas'firHazelnutTwinberryIndian plumSalmonberryRed elderberryTreesCrataegus douglasiiPinus contortaPseudotsuga menziesiiShrubCorylus cornutaLonicera involucrataOemleria cerasiformisRubus spectabilisSambucus rasemosaLegendScientific and common names: Scientific name according to Hitchcock and Conquist (1976) Flora of the Pacific NorthwestUSFWS 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.ative Plant NurseriesFourth Corner Nurseries, 3057 E. Bakerview Road Bellingham WA 98226 (360) 734-0079Shore Road Nursery, 616 Shore Road Port Angeles, WA 98362 (360) 457-8482Sound Native Plants, P.O. Box 7505, Olympia, WA 98507 (360) 943-7026Woodbrook Nursery, 162A 59th Ave. Gig Harbor WA 98335 (206) 265-627 |Olympic Wetland Resources, lnc. July 2005