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HomeMy WebLinkAbout31-RHS wetlands-Critical Areas Report-PUD.pdf Formerly DCG/Watershed SEATTLE | KIRKLAND | MOUNT VERNON | WHID BEY ISLAND | FEDERAL WAY | SPOKANE facetnw.com TECHNICAL MEMORANDUM Date: March 27, 2025 To: Renton School District, c/o Brianne Tomlin From: Anna Murphy, Ecologist Project Name: Renton High School Expansion Facet Number: 2502.0506.00 Renton High School Properties: Reconnaissance Study On September 20, 2021, Ecologist Anna Murphy visited the Renton High School campus located at 400 South 2nd Street in the City of Renton and adjacent properties to screen for jurisdictional wetlands and streams. This technical memo summarizes the findings of the study. Summary No jurisdictional wetlands or streams are present within or directly adjacent to the study area. No properties meet wetland criteria for hydrophytic vegetation, hydric soils, and wetland hydrology. No indications of flowing water or other stream indicators were observed on any property. Study Area The study area is defined as the Renton High School Campus (parcels 0007200060 & 3806000065) and select neighboring properties to the north and east side of the campus along Logan Avenue S, S Tobin Street, S Tillicum Street, and Airport Way as indicated in Figure 1. Access was granted to the school campus and all properties outlined in black in Figure 1. All properties outlined in green were assessed from the adjacent publicly accessible rights-of way and with the benefit of publicly-available aerial photos, topographic contours, inventories, and other resources. RENTON HIGH SCHOOL EXPANSION RECONNAISSANCE STUDY / 2 Figure 1. Study area outlined red and green. Entry permission was granted to parcels outlined in red and black; parcels outlined in green were screened from the nearest publicly accessible area. Methods The subject property was evaluated for wetlands using methodology from the Corps of Engineers Wetland Delineation Manual (Environmental Laboratory 1987) and the Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region Version 2.0 (Regional Supplement) (U.S. Army Corps of Engineers 2010). Presence or absence of wetlands was determined based on an examination of vegetation, soils and hydrology. Characterization of climatic conditions in the Wetland Determination Data Forms were determined using the WETS table methodology (USDA, NRCS 2015). The Bremerton station (from 1991-2020) was used as a source for precipitation data. The WETS table methodology uses climate data from the three months prior to the site visit month to determine if normal conditions are present in the study area region. The study area was evaluated for streams based on the presence or absence of an ordinary high water mark (OHWM) as defined by Section 404 of the Clean Water Act, the Washington Administrative Code (WAC) 220‐660‐030, and the Revised Code of Washington (RCW) 90.58.030. While some properties were not fully accessible during the site visit, these areas were small enough that an adequate assessment was possible from what could be seen from afar combined with aerial photos and other resources. Public‐domain information on the subject properties was reviewed for this study. Resources and review findings are presented in Table 1. RENTON HIGH SCHOOL EXPANSION RECONNAISSANCE STUDY / 3 Table 1. Summary of online mapping and inventory resources. Findings The study area is within the Madsen Creek-Cedar sub-basin of the Green-Duwamish watershed (WRIA 9); Section 18 of Township 23 North, Range 05 East of the Public Land Survey System. The study area is bordered by the Renton Municipal Airport to the north and a mix of commercial and single-family residential development to the east, west, and south. The Renton High School campus is developed with school buildings, paved parking lots, and a sports field in the east half of the parcel and a large sports field and tennis court in the west half. Both sports fields contain unvegetated gravel baseball diamonds with the remaining areas uniformly vegetated with regularly mowed lawn grass. Vegetation outside of the fields on the remainder of the campus consists of mostly ornamental shrubs and trees, mowed lawn, and mature oak trees, collectively a non- hydrophytic plant assemblage. The baseball diamonds within the school campus’ sports fields contained areas of ponded water, however these areas are likely not present for long durations and are purposefully highly compacted for their function and are therefore poorly draining. The assessed properties along Logan Avenue S, S Tobin Street, and S Tillicum Street are mostly small parcels with single family residences. Most of each parcel is developed, with the remaining undeveloped portions typically containing lawn grass, western red cedar (Thuja plicata) trees, cherry trees (Prunus sp.), and ornamental trees and shrubs. Properties along Airport Way are either vacant or contain commercial development. Vacant lots contain a mix of paved surfaces and and highly compacted soil. Resource Summary USDA NRCS: Web Soil Survey Entire study area mapped Urban land, a nonhydric soil USFWS: NWI Wetland Mapper Riverine wetland mapped along Cedar River approx. 280 feet northeast of study area. WDFW: PHS on the Web No features mapped. WDFW & NWIFC: Statewide Washington Integrated Fish Distribution No on-site features mapped. WA-DNR: Forest Practices Application Mapping Tool No on-site features mapped. Cedar River mapped as a Type S water is shown consistent with other resources. King County iMap No wetland or stream features mapped. Most of the property mapped within FEMA 500 year floodplain of the Cedar River. City of Renton maps No on-site features mapped. WETS Climatic Condition Normal RENTON HIGH SCHOOL EXPANSION RECONNAISSANCE STUDY / 4 Topography is relatively flat across the entire study area. No areas contain plant assemblages typically associated with wetland conditions. No locations within the directly assessed properties meet criteria for hydric soils. Soils tested in the sports fields and directly accessed properties areas are generally bright (displayed high chroma colors) and were very dry at the time of sampling. No indications of flowing water, erosion, scour or other stream indicators were observed on or near the properties. Site photos Figure 2. View of lawn grass non-wetland condition on the south edge of the school campus. Figure 3. View of oaks growing in a non-wetland condition along the south edge of the campus. RENTON HIGH SCHOOL EXPANSION RECONNAISSANCE STUDY / 5 Figure 4. View of the non-wetland condition sports field in the west half of the school campus. Figure 5. View of transient standing water non-wetland condition on a highly compacted baseball diamond on the school campus. RENTON HIGH SCHOOL EXPANSION RECONNAISSANCE STUDY / 6 Figure 6. View of lawn grass and ornamental shrubs non-wetland condition on a residential property within the study area. Figure 7. View of lawn grass and ornamentals shrubs and trees non-wetland condition on a residential property within the study area. RENTON HIGH SCHOOL EXPANSION RECONNAISSANCE STUDY / 7 Figure 8. View of non-wetland conditions on a vacant lot within the study area. Disclaimers The information contained in this document is based on the application of technical guidelines currently accepted as the best available science and in conjunction with the manuals and criteria referenced above. All discussions, conclusions and recommendations reflect the best professional judgment of the author(s) and are based upon information available at the time the study was conducted. All work was completed within the constraints of budget, scope, and timing. The findings of this report are subject to verification and agreement by the appropriate local, state, and federal regulatory authorities. No warranty, expressed or implied, is made.