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HomeMy WebLinkAboutWetland Delineation Report and Restoration Plan - PLN General - 4/11/2006 Lee Boad Habitat Management Planning and Wetland Services Wetland Delineation • Habitat Management Plans • Riparian Restoration • Mitigation • Biological Evaluation LBHMPWS-263 Pg 1 of 6 Wetland Delineation Report and Restoration Plan Parcel 12220-50-15003 60 E North Bay Road RECEIVED Allyn,WA 98524 APR 1 1 2006 1.0 Introduction MCCD - PLANNING At the request of Robert and Tiffany Ciambrone, Lee Boad Habitat Management Planning and Wetland Services performed a wetland reconnaissance on the above referenced property. This work was requested to determine the extent of wetlands present within a recently cleared area and to establish a restoration plan for the site. This report is formatted following the information recommended to be included in wetland reports by the Washington Department of Ecology (DOE 1997) and by the U.S. Army Corps of Engineers (USACOE 1987). The restoration component has been formatted following the requirements listed in chapter 17.01.210 of the Mason County Resource Ordinance. All field work and reporting was performed by Lee Boad. The following is a summary of methodology and findings. Technical data is attached. 2.0 Methodology 2.1 Field Review A field review of the above referenced property was performed throughout February and March of 2006. Review consisted of the following: 1) Reconnaissance throughout the parcel to identify suspected wetlands. 2) Routine determination sample plots completed within suspected wetlands. a. All sample plots were monitored for water table fluctuation over the course of three weeks. 3) Delineation and staking of wetland boundaries. 4) Field measurements to determine wetland location relative to property lines. 5) Analysis of nearby non-disturbed wetland sites to determine previous conditions. 6) Categorization of identified wetland based on previous conditions. 7) Determination of wetland surface area disturbed by recent clearing. 2.2 Wetland Delineation Wetland delineation followed a routine methodology based upon the Washington State Wetland Identification and Delineation Manual (1997) requiring positive indicators of wetland soil, hydrology, and plants. PO Box 2854 Belfair, Washington 98528•Cell Phone 360-620-0618.Office Phone 360-372-2421•boad40@peoplepc.com Wetland Delineation Mason County, Washington LBHMPWS263 Page 2 of 10 Wetland hydrology was determined through observation of field indicators and conditions dug in pits within the study area. Presence of hydric soil was determined by soil conditions in several pits dug around and within suspected wetlands. Soil inspection included comparison with the Munsell Color Charts (1992). General soil characteristics were derived from information contained within the Soil Survey of Mason County, Washington. (1960). Occurrence of wetland vegetation was determined through species identification, estimation of dominance and then assignment of wetland indicator status. Indicator status was assigned based on the National List of Plant Species That Occur in Wetlands (1996). Non-disturbed areas adjacent to the subject wetland were used to identify conditions that likely existed prior to clearing. Sample plot data has been recorded on routine wetland determination forms for the purpose of this work. A-typical data forms were not completed for this site because all three wetland parameters are still present despite the recent clearing activity. Although the vegetative community has been significantly altered, no portion of the wetland has been displaced by the non-permitted activity. 2.3 Wetland Category Rating Procedures set forth in the Washington State Wetlands Rating System — Western Washington Second Edition 1993 were used to establish category ratings for identified wetlands. 2.4 Wetland Mapping Mapping of wetland boundaries was completed through field measurements taken from property lines to staked wetland boundaries. All flagged wetland zones and associated buffers have been located and included on the site plan shown in Appendix A. 3.0 Results The ownership consists of approximately 1.8 acres accessed via an easement off of North Bay Road. The site is bordered to the west by North Bay Road and to the east by the shoreline of North Bay. Similar sized private ownerships border the property on the north and south. An area within the western portion of the property has been recently cleared while the eastern portion of the property appears to have been maintained historically as an open area. A stand of large cedars is present within the southwestern '/4 of the property while a pine stand is within the northwestern '14 . A house is centrally located on the eastern portion of the property approximately 30-feet from the marine shoreline. Wetlands Based on observed soil conditions and landscape patterns, the entire site appears to have historically supported wetland conditions extending from what is now North Bay Road to the marine shoreline. Groundwater springs and seasonal high water tables are evident throughout the western portion of the site. PO Box 2854,Belfair,WA 98528 cell:360-620-0618,Office: 360-372-2421 e-mail:boad40@peoplepc.com Wetland Delineation Mason County, Washington LBHMPWS263 Page 3 of 10 Over the course of several decades, measures have been taken to dry out the property and adjacent ownerships. A man-made drainage ditch runs east/west through the central portion of the property flowing into a small culvert located adjacent to the house. The culvert discharges onto the shoreline of North Bay. A more functional drainage system has been installed on the adjacent ownership to the north approximately 10-feet off the subject parcel which also provides an indirect drainage mechanism. Gravel fill has been added to the site to provide vehicle access to western portions of the property. These modifications appear to have been completed prior to regulation and are not issues addressed in the restoration component of this report. Prior to the recent non-permitted vegetation removal, the site appears to have been a scrub shrub community dominated almost entirely by salmonberry. Soil The soil type mapped and confirmed throughout the entire site is McKenna gravelly loam which is a poorly drained, very dark, gravelly soil, high in organic matter. This soil is common within depressions and natural drainageways. Under natural conditions this soil occurs in areas that are saturated for most of the year but dry out rapidly in the summer. This soil is in Capability Class IVw which almost always supports wetlands in a natural state. Non-wetland portions of the study site are underlain by soil similar to what occurs in the identified wetland. This is likely due to the historical presence of wetlands throughout the entire property. Site Location Figure 1.Soil map showing project site Hydrology Identified wetlands function as groundwater depression wetlands that also receive surface water from the surrounding area. Observed indicators of wetland hydrology include drainage patterns, FAC neutral vegetation, local soil survey information and observation of standing water. The wetland portion of the site appears to be supported mostly by groundwater due to the presence of underground springs. With the exception of the marine shoreline the wetland is located in the lowest point of the watershed causing it to also function as a receptor of upland runoff from the surrounding area. The man made drainage ditch appears to have reduced the distribution of wetland hydrology associated with the site. Much of the water that historically saturated the majority of the property is now channeled directly into North Bay. This is made evident by the presence of hydric soil PO Box 2854, Belfair,WA 98528 cell:360-620-0618,Office:360-372-2421 e-mail:boad40@peoplepc.com Wetland Delineation Mason County, Washington LBHMPWS263 Page 4 of 10 identified in sample plots that currently do not meet wetland criteria due to the lack of hydrological and vegetation indicators. Although the soil throughout the entire property was formed under wetland conditions, wetland hydrology has been reduced by the presence of the drainage ditch. Fide* 1. t Figure 2. Man-made ditch intended to drain wetland Vegetation Recent land clearing has left the majority of the wetland within the property comprised of exposed soil with scattered wetland plants. Vegetation identified within the wetland zone is primarily herbaceous species common to disturbed sites. Species identified include creeping buttercup (Ranunculus repens), soft rush (Juncus effuses), Baltic rush (Juncos balticus), reed canarygrass (Phalarys arundinacea), and slough sedge (Carex obnupta). The northwestern portion of the site is comprised of a stand of alder (Alnus rubra), and knotty pine (Pinus corntorta) underlain by a herbaceous community of slough sedge (Carex obnupta). Prior to vegetation removal salmonberry(Rubus spectabilis) likely dominated this understory as well. Non-disturbed wetland communities adjacent to the project site are scrub shrub communities dominated almost entirely by a dense layer of salmonberry with an underlying herbaceous layer of slough sedge in some areas. PO Box 2854, Belfair, WA 98528 cell:360-620-0618,Office:360-372-2421 e-mail:boad40@peoplepc.com Wetland Delineation Mason County, Washington LBHMPWS263 Page 5 of 10 r k � Figure 3.non-disturbed areas adjacent to the clearing are predominantly salmonberry communities with interspersed alder. Boundary Description The wetland boundary is non-distinct in terms of vegetation and soil characteristics. Reed cannarygrass extends onto non-wetland sample plots in almost all areas. The primary rational used in identifying the wetland edge was hydrological indicators and conditions in soil pits. Over the course of three weeks, the site was monitored prior to, during, and following rain events to determine which plots are most likely to maintain water tables within 12-inches of the soil surface for 12% of the growing season. Sample plots with water tables falling below 12-inches of the soil surface 1-2 days following rain events were considered upland. All other sample plots maintained water tables within 12-inches of the soil surface over the course of the entire study and therefore have been identified as wetland zones. Jurisdictional Status The identified wetland prior to clearing would score greater than 22-points on the field data form qualifying it as a jurisdictional Category II Wetland according to the Washington State Wetlands Rating System — Western Washington Second Edition and the wetlands chapter of the Mason County Resource Ordinance. Key factors influencing this rating include overall size (> 2,500 square feet), plant species diversity, contribution to fish bearing water, structural diversity, association with nearby shoreline, presence of habitat features, and condition of surrounding buffer. Category II Wetlands require a vegetation area of 85 feet and a building setback of 100 feet according to the wetlands chapter of the Mason County Resource Ordinance. Special setbacks include 100 feet for a septic drainfield and 200 feet for a livestock feedlot. PO Box 2854, Belfair, WA 98528 cell:360-620-0618,Office: 360-372-2421 e-mail:boad40@peoplepc.com Wetland Delineation Mason County, Washington LBHMPWS263 Page 6 of 10 The eastern portion of the identified wetland has been maintained as an open lawn area. Such use is grandfathered and can therefore be maintained within the existing lawn. Additional drainage features and fill would still not be permitted. Other Waters Identified The marine shoreline associated with the ownership is regulated as a Type 1 Conservancy shoreline requiring a 100 foot buffer and additional 15-foot building setback. Existing uses are grandfathered but can not be expanded. Restoration Plan Extent of Disturbance Recent disturbance has included vegetation removal within approximately 16,500 square feet of the identified wetland. According to non-disturbed wetland areas on the adjacent property to the north, it appears that the vegetative community displaced was dominated primarily by salmonberry with interspersed alders. As the entire property is encompassed by either wetlands or regulated buffers,restoration of all recently cleared areas is required with the exception of areas historically maintained as open lawn,buildings, or access roads. Although operation of heavy equipment has left moderate depressions and vehicle tracks, it does not appear that significant grading, filling, or ditching has been associated with recent non-permitted activity. Landscape topography has been maintained. The majori of the cleared area is now ex sed erodible soil partially covered with dead salmonberry stems and some newly established herbaceous wetland plants. Himalayan . blackberry seedlings are within the cleared zone as well. Measures for Restoration Salmonberry(Rubus spectabilis) should be planted throughout the cleared area at a 3-5 foots spacing to stabilize erodible soil P g • �� and prevent the site from being overcome by invasive species such as Himalayan blackberry. It is expected that red alder , will seed naturally given the pioneering y nature of the species and abundance of surrounding seed recruitment. Planting should occur as soon as possible to prevent invasion of the site by exotic species. Given that the optimal time for planting(winter)has nearly past it is recommended that potted plants be used. Given the surface area to be restored approximately 1,030 plants will be required to restore the disturbed area using the recommended spacing. The standard survival rate for restoration success is 80%after three years. Exotic species should be continuously removed from the site. Himalayan blackberry are most likely to become established and should be removed if they begin to establish. PO Box 2854, Belfair, WA 98528 cell:360-620-0618,Office:360-372-2421 e-mail:boad40@peoplepc.com Wetland Delineation Mason County, Washington LBHMPWS263 Page 7 of 10 Schedule for Restoration Do to the high potential for the site to be overcome by invasive species if left as is,restoration of the site should commence as soon as possible and be completed no later than April 15th 2006. Monitoring Monitoring of the site should commence initially on a three month basis beginning in July, 2006. The primary purpose is to insure that exotic species do not establish. After the first year an annual monitoring review will be sufficient, given that objectives are met. The information gathered will provide the following: 1) condition of reintroduced plant species; 2) the use of the site by wildlife species; 3) any previously unidentified disturbance caused by the clearing and its effect on the wetland; 4) any occurrence of exotic species within the Restoration Zone; 5) any corrective measures necessary to provide desired conditions. The overall monitoring program will be in effect for the duration of three years. The information gathered will be provided in an annual report and submitted to the Director of Mason County Department of Community Development. Performance Bond Mason County will require a performance bond for the installation and monitoring of the restoration. The cost of plant installation assumes $7.00 per plant which includes labor. This cost estimate was obtained from Wilderness Outdoor Designs Professional Landscaping, Maple Valley WA. (Patrick Jennings: 206-200-4817). Our monitoring estimate assumes $200 per visit and would include a total of 5 visits. This results in a total bond amount of$8,180. Estimates can be obtained from other contractors which may result in a different bond amount. The total bond amount will need to be deposited prior to permit approval and be released to the depositor on successful completion of the recommended mitigation and monitoring as applicable. 4.0 Conclusion Wetland delineation has been completed applying a standardized methodology required by the Mason County Resource Ordinance. The identified jurisdictional wetlands uphold positive indicators and meet DOE rating criteria for Category H Wetlands in Mason County. Non-permitted land clearing has been addressed through the restoration plan provided. A scaled map is enclosed showing the location of identified wetlands, cleared area/restoration zone, and other relevant features in relation to property boundaries. I trust this information is sufficient for your needs at this time. Thank you for choosing me as your environmental consultant. If you have any questions feel free to call. Lee Boad Senior Ecologist Attached: Appendix A: Vicinity Map Appendix B: Site Map Appendix C: National Wetlands Inventory Appendix D: Wetland Determination Data PO Box 2854,Belfair,WA 98528 cell:360-620-0618,Office: 360-372-2421 e-mail: boad40@peoplepc.com The Wetland Corps ClI&*:Pobert Cwnbra e ra-cal #12220-50-15003 60� Nat l Pay Road scAe:1"-40'-0 A 14n,WA 98924 Man-made lAck on Adjacent Property i Case Wet Cleared Area to be Restared (.WoK 16,500 5q R) 1'ottted 5elmo+aT4 5eed"3-5 foot 5pw q �\ �xisttq Nome �� i Man-made IA 1/ V� pod- Category II Wetland O If If 85' Puffer i � �