2019 wetland monitoring report...mar 31, 2020 · this report summarizes final-year (year-10)...

2019 WETLAND MONITORING REPORT

WSDOT and City of Renton Springbrook Creek Wetland and Habitat

Compensatory Mitigation Bank Unit C

USACE IP 2006-00100

Northwest Region

Wetlands Program Issued March 2020

Prepared By: Evan Dulin

Editor:

Kristen Andrews

Other Contributors: Sean Patrick

Amanda Mintz

For additional information about this report or the WSDOT Wetlands Program, please contact:

Kristen Andrews, Wetlands Program WSDOT, Environmental Services Office

P. O. Box 47332, Olympia, WA 98504 E-mail: [email protected]

Phone: 360-570-2588

Monitoring reports are published on the web at: http://www.wsdot.wa.gov/environment/technical/disciplines/wetlands/monitoring-reports

mailto:[email protected]

http://www.wsdot.wa.gov/environment/technical/disciplines/wetlands/monitoring-reports

http://www.wsdot.wa.gov/environment/technical/disciplines/wetlands/monitoring-reports

Title VI Notice to Public It is the Washington State Department of Transportation’s (WSDOT) policy to assure that no person shall, on the grounds of race, color, national origin or sex, as provided by Title VI of the Civil Rights Act of 1964, be excluded from participation in, be denied the benefits of, or be otherwise discriminated against under any of its federally funded programs and activities. Any person who believes his/her Title VI protection has been violated, may file a complaint with WSDOT’s Office of Equal Opportunity (OEO). For additional information regarding Title VI complaint procedures and/or information regarding our non-discrimination obligations, please contact OEO’s Title VI Coordinator at (360) 705-7090. Americans with Disabilities Act (ADA) Information This material can be made available in an alternate format by emailing the Office of Equal Opportunity at [email protected] or by calling toll free, 855-362-4ADA(4232). Persons who are deaf or hard of hearing may make a request by calling the Washington State Relay at 711.

https://www.wsdot.wa.gov/EqualOpportunity/titlevi.htm

https://www.wsdot.wa.gov/EqualOpportunity/ADA.htm

Springbrook Unit C Wetland and Habitat Compensatory Mitigation Bank 2019 Monitoring Report i

Site Summary Springbrook Creek Wetland and Habitat Compensatory Mitigation Bank Unit C USACE IP 2006-00100

General Site Information

USACE IP Number 2006-00100

Mitigation Location Southwest Renton, King County

LLID Number 1222395474429

Monitoring Period 2010–2019

Year of Monitoring 10 of 10

Springbrook Unit C Wetland and Habitat Compensatory Mitigation Bank 2019 Monitoring Report ii

Table of Contents Site Summary........................................................................ i

1. Introduction ................................................................ 1

1.1. Summary ........................................................... 1

1.2. Monitoring Results and Management Activities .. 1

2. Site Description ......................................................... 2

2.1. Location ............................................................. 2

2.2. Purpose and Description ................................... 2

2.3. Study Area ......................................................... 3

3. Performance Standards and Methods ....................... 4

3.1. Performance Standards ..................................... 4

3.2. Methods............................................................. 5

4. Discussion ................................................................. 6

4.1. Site Development .............................................. 6

4.2. Results .............................................................. 7

4.3. Site Management Activities................................ 9

5. References .............................................................. 10

Figures Figure 1. Site Sketch ........................................................... 3

Figure 2. Sample Design ..................................................... 5

Figure 3. Perimeter fence extension overview and profile. .. 9

Appendices Appendix A. As-Built ..................................................... 11

Appendix B. Photo Points and Photo Point Locations ... 15

Appendix C. Wetland Delineation Report ...................... 18

Springbrook Unit C Wetland and Habitat Compensatory Mitigation Bank 2019 Monitoring Report 1

1. Introduction 1.1. Summary This report summarizes final-year (Year-10) monitoring activities at the Springbrook Unit C Wetland and Habitat Compensatory Mitigation Bank. Included are a site description, the performance standards, an explanation of monitoring methods, and an evaluation of site success. Monitoring activities included vegetation surveys and photo-documentation on August 26, 27, and November 7, and a wetland delineation on March 18, 26, and April 3 in 2019.

1.2. Monitoring Results and Management Activities Performance Standards 2019 Results1 Management Activities

Wetland delineation, at least 9.27 acres of wetland in the wetland reestablishment areas See delineation report in Appendix C

At least 75% cover native, woody vegetation in the tree/shrub planting areas 100% (CI80% = 99-100%)

At least two species provide at least 10% aerial cover each in the tree/shrub planting areas Achieved (six species)

At least 50% cover native, woody vegetation in the upland planting areas 100% (CI80% = 100-100%)

At least two species provide at least 7% aerial cover each in the upland planting areas Achieved (eight species)

At least 70 conifers/acre in the forested wetland enhancement areas 73 conifers/acre (CI80 = 59-88)

Pruning of competing woody species less than 4-inch around planted conifers was conducted in fall 2019

Less than 10% cover by Himalayan blackberry (Rubus armeniacus) in the wetland reestablishment area, and less than 20% cover across the rest of the site; No Japanese knotweed (Reynoutria japonica), English ivy (Hedera helix), or purple loosestrife (Lythrum salicaria) across the site

1% cover (qualitative) for entire site; Some Japanese knotweed was observed (<1% cover)

Weed control was conducted in September 2019

1 Estimated values are presented with their corresponding statistical confidence interval. For example, 100% cover (CI80% = 99-100%) means we are 80% confident that the true cover value is between 99% and 100%.


2. Site Description2.1. Location This approximately 48-acre compensatory mitigation bank site is one unit (Unit C) of the larger Springbrook Creek Wetland and Habitat Compensatory Mitigation Bank complex. All five units are located in the southwestern portion of the City of Renton in King County (Figure 1).

2.2. Purpose and Description The purpose of the compensatory mitigation bank is to provide compensation for unavoidable impacts to wetlands and other aquatic resources caused by WSDOT highway construction projects and City of Renton mitigation requirements within the service area. This 47.48-acre site includes 27.9 acres of pre-existing wetlands and provides numerous wetland and aquatic functions. The bank is operated and managed by WSDOT and the City of Renton.


2.3. Study Area The Springbrook Unit C Wetland and Habitat Compensatory Mitigation Bank contains a mosaic of reestablished, rehabilitated, and enhanced wetlands as well as enhanced uplands and riparian areas adjacent to Springbrook Creek (Figure 1). This site, along with the other units of the larger mitigation bank complex, represents some of the last remaining large tracts of undeveloped land in the Green River Basin.

Figure 1. Site Sketch


3. Performance Standards and Methods 3.1. Performance Standards Year 10 Performance Standard 1 In Years 5 and 10, at least 9.27 acres of wetland will be present within the wetland reestablishment area in Unit C.

Performance Standard 2 In Year 10, native woody vegetation within the wetland tree/shrub planting areas will provide at least 75 percent aerial cover.

Performance Standard 3 In Year 10, at least two species will provide at least 10 percent aerial cover each within the wetland tree/shrub planting area.

Performance Standard 4 In Year 10, native woody vegetation within the upland planting areas will provide at least 50 percent aerial cover.

Performance Standard 5 In Year 10, at least two species will provide at least seven percent aerial cover each in the upland planting areas.

Performance Standard 6 In Years 1, 5, and 10, the forested wetland enhancement areas will contain at least 70 living native conifers per acre.

Performance Standard 7 In Years 5 and 10, Himalayan blackberry will not cover more than 20% of the forested wetland enhancement, upland planting areas, and buffers at the site, and not more than 10% in the wetland reestablishment area. In Years 1 through 10, remove all Japanese knotweed, English ivy, and purple loosestrife identified within Unit C.

Appendix A shows the As Built (WSDOT 2010).


3.2. Methods WSDOT staff performed a wetland delineation using methods described in the Corps of Engineers Wetlands Delineation Manual (Environmental Laboratory 1987), Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (Version 2.0) (USACE 2010) (Performance Standard 1). A Global Positioning System (Trimble Mapping Grade) was used to collect spatial data.

The tables below document sample methods used for all of the remaining performance standards (PS) required by the mitigation bank plan. Additional details on our methods are located here: WSDOT Wetland Mitigation Site Monitoring Methods Paper (WSDOT 2008).

Figure 2. Sample Design

Sample units were randomly positioned across the applicable zones. Some sample unit quadrats (density) and line intercepts (cover) were adjusted north/south or east/west to fit within the applicable zones within a pre-determined set tolerance distance.

PS 2 & 3 PS 4 & 5 PS 6 PS 7 Attribute Cover Cover Density Cover

Target population Native woody

species

Native woody species Conifers

Noxious/ invasive

Zone Wetland Tree/Shrub Planting Area

Upland Planting Area

Forested Wetland Enhancement Entire Site

Sample method Line Intercept

Line Intercept Quadrat Qualitative

SU length 10 10 40 SU width 10

Total # of SU 5 6 16

https://www.wsdot.wa.gov/sites/default/files/2018/02/22/Env-Wet-MonitoringMethods.pdf


4. Discussion 4.1. Site Development Unit C has developed as intended and is meeting all final-year vegetation performance standards (see Appendix C for the wetland delineation report and discussion of Performance Standard 1). Native woody cover throughout the entire site and in all planting areas is near 100 percent and is very dense. These planting areas are comprised of a diverse community of trees and shrubs.

The under-plantings of western red cedar (Thuja plicata), Sitka spruce (Picea sitchensis), and western hemlock (Tsuga heterophylla) appear healthy and are meeting the final-year conifer density standard. Some areas in the conifer underplanting zone are too wet to allow conifer survival; therefore, additional conifers were installed in other parts of the conifer underplanting zone to provide a similar number of conifers on-site, as required by the plan, and still provide the intended function. Plots were randomly dispersed across the entire intended underplanting area and resulted in three plots with no conifers recorded because they randomly fell within the areas that are too wet for conifer growth. If these plots are excluded from the sample, than the conifer density increases from 73 conifers/acre to 90 conifers/acre, both situations are meeting the final-year performance standard.

Invasive species cover remains low across the entire site with only a few small scattered patches of Himalayan blackberry and reed canarygrass (Phalaris arundinacea) in areas where the canopy lets enough light to the forest floor to allow growth, which occurs rarely across the site. A small patch of Japanese knotweed was observed along the western portion of the northern site boundary. Weed control of this species and other targeted noxious weeds will continue.

Garter snakes (Thamnophis sp.), banana slugs (Ariolimax sp.), banded garden snails (Cepaea hortensis), wooly caterpillar (Pyrrharctia isabella), coyote scat, black-capped chickadees (Poecile atricapillus), a red-tailed hawk (Buteo jamaicensis), and numerous dead American crows (Corvus brachyrhynchos) were observed during the August and November monitoring visits.


4.2. Results Performance Standard 1 (Wetland delineation, at least 9.27 acres of wetland in the wetland reestablishment areas)

The site was delineated in spring 2019. See Appendix C for a discussion of the results.

Performance Standard 2 (At least 75% cover native, woody vegetation in the tree/shrub planting areas)

Cover of native woody vegetation in the wetland tree/shrub planting areas is estimated at 100% (CI80%= 99-100%) (Photo 1). This is above the performance standard target.

Performance Standard 3 (At least two species provide at least 10% aerial cover each in the tree/shrub planting areas)

Six species are each providing at least 10% aerial cover in the tree/shrub planting area, including black cottonwood (Populus balsamifera), quaking aspen (Populus tremuloides), Pacific willow (Salix lasiandra), Sitka willow (Salix sitchensis), Oregon ash (Fraxinus latifolia), and twinberry honeysuckle (Lonicera involucrata).

Photo 1. Woody cover in wetland tree/shrub planting area (August 2019)

Photo 2. Woody cover in the upland planting area (August 2019)


Performance Standard 4 (At least 50% cover native, woody vegetation in the upland planting areas)

Cover of native woody vegetation in the upland planting areas is estimated at 100% (CI80%= 100-100%) (Photo 2). This is above the performance standard target. This is above the performance standard target.

Performance Standard 5 (At least two species provide at least 7% aerial cover each in the upland planting areas)

Eight species are each providing at least 7% aerial cover in the upland planting area, including redosier dogwood (Cornus alba), black cottonwood, snowberry (Symphoricarpos albus), red alder (Alnus rubra), Scouler's willow (Salix scouleriana), Douglas-fir (Pseudotsuga menziesii), Pacific willow, and bigleaf maple (Acer macrophyllum).

Performance Standard 6 (At least 70 conifers/acre in the forested wetland enhancement areas)

The estimated density within the forested wetland enhancement areas is estimated at 73 conifers/acre (CI80 = 59-88), or 90 conifers/acre (CI80 = 81-100) when the plots in wet areas are excluded. Both of these data analyses are above the performance standard target.

Photo 3. Conifer density in forested wetland enhancement area (November 2019)

Performance Standard 7 (Less than 10% cover by Himalayan blackberry in the wetland reestablishment area, and less than 20% cover across the rest of the site; No Japanese knotweed, English ivy, or purple loosestrife across the site)

The cover of Himalayan blackberry across the entire site is less than 1%, including about 1% cover in the wetland reestablishment areas. The site is meeting this performance standard. A small patch of Japanese knotweed was observed along the western portion of the northern site boundary, overall less than 1% cover within the site.


4.3. Site Management Activities Weed control is ongoing at Unit C. In 2020 weed control will be accomplished throughout the entire site, including the removal of Japanese knotweed where present. Pruning was conducted in fall 2019 in part of the Unit C conifer underplanting areas to decrease competition with planted conifers. The remaining areas of conifer underplanting will receive similar pruning in 2020.

A site perimeter fence extension was built at the NE corner of Unit C, extending the fence to the West by 50 feet (Figure 3). This fence was installed to help limit trespass into the mitigation bank site.

Figure 3. Perimeter fence extension overview and profile.


5. References 1. Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Vicksburg (MS): US Army Engineer

Waterways Experiment Station. Technical Report Y-87-1. Available at: http://www.swl.usace.army.mil/Portals/50/docs/regulatory/wlman87.pdf

2. [USACE] US Army Corps of Engineers. 2006. Department of the Army Individual Permit Number 2006-00100.

3. [USACE] US Army Corps of Engineers. 2010. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (Version 2.0), Wakeley JS, Lichvar RW, Noble CV, editors. Vicksburg (MS): US Army Engineer Research and Development Center. ERDC/EL TR-10-3. Available at:https://www.usace.army.mil/Missions/Civil-Works/Regulatory-Program-and-Permits/reg_supp/

4. [WSDOT] Washington State Department of Transportation. 2006. Springbrook Creek Wetland and Habitat Mitigation Bank Instrument. Seattle (WA): Washington State Department of Transportation, Northwest Region.

5. [WSDOT] Washington State Department of Transportation. 2008. WSDOT Wetland Mitigation Site Monitoring Methods. https://www.wsdot.wa.gov/sites/default/files/2018/02/22/Env-Wet-MonitoringMethods.pdf

6. [WSDOT] Washington State Department of Transportation. 2009. I-405 Springbrook Creek Wetland and Habitat Mitigation Bank Units C As-Built Report.

7. [WSDOT] Washington State Department of Transportation. 2010. Revised: I-405 Springbrook Creek Wetland and Habitat Mitigation Bank Units C As-Built Report.

http://www.swl.usace.army.mil/Portals/50/docs/regulatory/wlman87.pdf

https://www.usace.army.mil/Missions/Civil-Works/Regulatory-Program-and-Permits/reg_supp/

https://www.wsdot.wa.gov/sites/default/files/2018/02/22/Env-Wet-MonitoringMethods.pdf


Appendix A. As-Built (from WSDOT 2010)


Appendix B. Photo Points and Photo Point Locations The photographs below were taken from permanent photo-points on August 26 and 27, 2019 and document site success.

Photo Point 1a Photo Point 1b

Photo Point 1c

Photo Point 1d


Photo Point 2a Photo Point 2b

Photo Point 2c

Photo Point 3a


Photo Point 3b Photo Point 4a

Photo Point 4b


Appendix C. Wetland Delineation Report

WETLAND DELINEATION REPORT UPDATE VERIFICATION OF WETLAND BOUNDARY

Springbrook Creek Wetland and Habitat Mitigation Bank – Unit C

Project Name USACE IP 200600100

King County, Washington

Prepared by: Evan Dulin

WSDOT Environmental Services Office Olympia, Washington

March 2020

Springbrook Bank Unit C February 2020 Wetland Delineation Report Update 1

Introduction This report was prepared by the Washington State Department of Transportation (WSDOT) to describe the wetland boundary delineation for Springbrook Creek Wetland and Habitat Mitigation Bank Unit C (Springbrook Bank Unit C). Field work was conducted by WSDOT wetland biologists Tatiana Dreisbach, Trace McKellips, Evan Dulin, and Amanda Mintz, on March 18, March 26, and April 3, 2019. The delineation identifies 8.45 acres of wetland within the defined study area (Figure 2). The delineation focused on the wetland re-establishment areas of Springbrook Bank Unit C. Areas outside of the Springbrook Bank Unit C study area were not assessed for wetlands.

The wetland was previously delineated in April 2014 (WSDOT 2014). The purpose of the 2019 field work was to reevaluate the 2014 wetland boundary and document any wetland boundary modifications if necessary. The 2019 delineation occurred during a period with drier than normal precipitation conditions (Appendix B-1). WSDOT plans to reevaluate the 2019 delineation in spring 2020 in anticipation of a potential period with normal precipitation conditions preceding field work.

General Information for the Springbrook Bank Unit C

Location: S25, T23N, R4E. King County. (Figure 1)

USACE IP Number 200600100

Long./Lat. ID Number 1222330474518

Land Resource Region (LRR) A

Major Land Resource Area (MLRA) 2

Monitoring Period 2010 - 2019

Year of Monitoring 10 of 10 (in 2019)

Area of Project Impact1 Provides advance mitigation for future projects

Type of Mitigation Required Acreage2 2019 Delineated Acreage

Wetland Re-establishment 9.27 8.31

Total Delineated Wetland Area

In addition to 8.31 acres of wetland within the wetland re-establishment area, 0.14 acre of wetland is present in the surrounding Upland Habitat Enhancement and Protection Setback (Buffer) mitigation areas within the study area. The total delineated wetland area within the study area is 8.45 acres (Figure 2).

1 Project permitted under USACE Individual Permit 200600100 (USACE 2006). 2 Required acreage is outlined in the


Location

Figure 1. Vicinity Map


Methods Wetland boundaries within the Springbrook Bank Unit C were verified and amended as necessary using routine methods described in the:

• Corps of Engineers Wetlands Delineation Manual (Environmental Laboratory 1987),

• Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (Version 2.0) (USACE 2010)

Wetland boundaries were delineated based on on-site observations of hydrology, soils, and plant communities, in conjunction with background information.

A Global Positioning System (GPS) equipped Panasonic Toughpad paired with a Trimble R2 Global Navigation Satellite System (GNSS) Receiver mapping grade unit was used to:

• Navigate to 2014 delineation boundary. • Record 2019 sampling point locations. • Record 2019 wetland boundary amendments where necessary (Figure 2).

Wetland mitigation types were georeferenced by digitizing the Unit C Mitigation Types Figure 2-3 from the Springbrook Creek Wetland Habitat Mitigation Bank Mitigation Bank Instrument (WSDOT 2006) in ArcGIS 10.6.1. Inherent in both GPS and georeferencing are minute errors, resulting in slight inaccuracies in both boundary line placement and acreage calculations. These tools represent the best available methods at the time of the study and report preparation.

Wetland Delineation and Study Area Study Area Wetlands described in this report were evaluated within the study area (Figure 2) and focused on assessment of wetland re-establishment areas of Springbrook Bank Unit C. Additional wetland enhancement areas are present within the Springbrook Bank Unit C site boundary, primarily west of the study area, but were not included in the 2019 delineation. The site boundary and study area are not the same for this delineation (Figure 2).

Wetland Changes Since 2014 Springbrook Bank Unit C remains in similar condition as documented in 2014 with the exception of some wetland boundary variations in the wetland re-establishment area and further development of the vegetation community. The wetland acreage within the wetland re-establishment area decreased compared to the 2014 delineation and may be attributed to the fact that 2014 had a wetter than normal three month period preceding the field work (WSDOT 2014) compared to the drier than normal three month period preceding the 2019 field work (Appendix B-1). WSDOT intends to reexamine the


wetland boundary in spring 2020, in anticipation of a potential period with normal precipitation conditions preceding the site visit.

The wetland vegetation community continues to increase in height and cover. Woody cover provides an almost closed canopy with some small open canopy areas in the wetland re-establishment area, where mature black cottonwood (Populus balsamifera) trees have fallen. These canopy gaps contribute to habitat complexity of the site.

Wetland Boundary Verification The 2019 delineation verification determined 8.31 acres of wetland were present within the wetland re-establishment area, with 0.14 acre of wetland occurring in adjacent areas. The total delineated wetland area includes 8.45 acres within the defined study area for the Springbrook Bank Unit C (Figure 2). Minor wetland boundary amendments were made in 2019 and likely represent minor changes in observable field conditions and variations in yearly precipitation accumulation.

Wetland areas beyond the 2019 study area and within the site boundary were not included in this delineation.

Delineation data were collected at four sampling points and recorded on wetland determination data forms (Appendix A). Paired wetland and upland sample points were used to define the wetland edge and were placed in locations:

• Documenting where the wetland boundary has remained unchanged. • Where the wetland boundary required adjustment.

Data recorded on wetland determination data forms characterize typical wetland and upland conditions observed on site. Vegetation, soils, and hydrology were examined in many additional sampling locations to determine the wetland boundary.

Precipitation The Regional Delineation Supplement Version 2.0 (USACE 2010) recommends using methods described in Chapter 19 in Engineering Field Handbook (NRCS 2015) to determine if precipitation occurring in the three full months prior to the site visit was normal, drier than normal, or wetter than normal. Actual rainfall is compared to the normal range of the 30-year average. When considering the three prior months as a whole, drier than normal precipitation conditions were present prior to field work. Two of the three months prior to field work were drier than normal with the second prior month within the normal range (Appendix B-1). Light precipitation was recorded in the ten days preceding each of the field work days (Appendix B-2).

Growing Season The following evidence of the growing season was observed at the time of the delineation: the leaves on most woody species were partially or fully emerged, including willows (Salix spp.), Pacific ninebark (Physocarpus capitatus), hardhack (Spiraea douglasii), redosier dogwood (Cornus alba), snowberry (Symphoricarpos albus), and twinberry honeysuckle (Lonicera involucrata).


Figure 2. 2019 Delineation and Mitigation Types Map.


Springbrook Bank Unit C – Wetland Delineation Summary

Total Delineated Wetland Area 8.45 acres (additional wetland area is present within the site boundary, however the delineation did not include the entire site but rather focused on re-establishment areas)

Wetland Determination Data Forms

Appendix A; Sampling Points W1-SP1 and W1-SP3

Upland Determination Data Forms

Appendix A; Sampling Points W1-SP2 and W1-SP4

Delineators Tatiana Dreisbach Trace McKellips Evan Dulin Amanda Mintz

Delineation Date March 18, 2019 March 26, 2019 April 3, 2019

Vegetation Trees – black cottonwood, red alder (Alnus rubra), Sitka willow (Salix sitchensis), Shrubs – Nootka rose (Rosa nutkana), twinberry honeysuckle, Pacific ninebark, redosier dogwood Herbs – creeping buttercup (Ranunculus repens)

Soils Soils examined to a depth of 16 inches exhibited hydric characteristics. Matrix colors of 10YR 3/2, 10YR 4/1, 2.5Y 3/1, and 2.5Y 5/2 were observed. Redoximorphic concentrations and depletions were observed in most layers. Indicators Depleted Below Dark Surface (A11) and Depleted Matrix (F3) were met.

Hydrology

A high groundwater table associated with the Green River is the predominant source of hydrology. Surface water also contributes hydrology, flowing over an inlet berm at the southwest corner of the wetland re-establishment area and through the site to a weir structure at the northeast corner of the wetland re-establishment area. Precipitation also provides direct hydrologic inputs. Inundation was present in some interior portions of the wetland area at greater than 12 inches of standing water. Other areas had a water table or saturation in observation pits within 12 inches of the soil surface. Water marks and water-stained leaves were also observed in many areas.

Rationale for Delineation

Positive indicators of all three wetland criteria are present. Placement of boundary determined by presence/absence of wetland hydrology indicators and a change in soil matrix from chroma 2 (in wetland) to chroma 3 (in upland). In addition, some upland areas had Pacific madrone (Arbutus menziesii) volunteering.

Limitations This wetland delineation report documents the investigation, best professional judgment, and conclusions of WSDOT based on the site conditions encountered at the time of this study. The wetland delineation was performed in compliance with accepted standards for professional wetland biologists and applicable federal, state, and local ordinances. It is correct and complete to the best of our knowledge. It should be considered a preliminary jurisdictional determination of wetlands and other waters until it has been reviewed and approved in writing by the appropriate jurisdictional authorities.


References 1. Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual.

Vicksburg (MS): US Army Engineer Waterways Experiment Station. Technical Report Y-87-1. Available from: https://usace.contentdm.oclc.org/digital/collection/p266001coll1/id/4530

2. [NRCS] Natural Resource Conservation Service. 2015. Hydrology Tools for Wetland Identification and Analysis. Chapter 19 in Part 650 Engineering Field Handbook. Pages 19-85 through 19-89. US. Department of Agriculture, NRCS. Available from: https://directives.sc.egov.usda.gov/OpenNonWebContent.aspx?content=37808.wba

3. [NRCS] Natural Resources Conservation Service [Internet]. 2019. Field Office Technical Guide. US Department of Agriculture. Climate Data for King County, Station Kent, Washington 454169. [cited 2020 Jan 2]. Available at: http://agacis.rcc-acis.org/

4. [NRCS] Natural Resource Conservation Service [Internet]. 2019. Web Soil Survey for King County, Washington. US Department of Agriculture. [cited 2020 Jan 6]. Available at: http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx

5. US Army Corps of Engineers. 2016. National Wetland Plant List, version 3.3 [Internet]. US Army Corps of Engineers, Engineer Research and Development Center, Cold Regions Research and Engineering Laboratory, Hanover, NH. Available at: http://rsgisias.crrel.usace.army.mil/NWPL/

6. [USACE] US Army Corps of Engineers. 2006. Department of the Army Individual Permit Number 200600100.

7. [USACE] US Army Corps of Engineers. 2010. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (Version 2.0), ed. Wakeley JS, Lichvar RW, Noble CV, editors. Vicksburg (MS): US Army Engineer Research and Development Center. ERDC/EL TR-10-3. Available at: http://www.usace.army.mil/Portals/2/docs/civilworks/regulatory/reg_supp/west_mt_finalsupp.pdf

8. [WSDOT] Washington State Department of Transportation. 2006. Springbrook Creek Wetland and Habitat Mitigation Bank Mitigation Bank Instrument. Seattle (WA): Washington State Department of Transportation, Northwest Region.

9. [WSDOT] Washington State Department of Transportation. 2014. Springbrook Creek Wetland and Habitat Mitigation Bank Site Unit C Wetland Delineation Report. Olympia (WA): Washington State Department of Transportation, Headquarters Environmental Services Office.

10. [WSDOT] Washington State Department of Transportation. 2019. Wetland Reconnaissance and Assessment [Internet]. Olympia (WA): Environmental Services Office. [cited 2020 Jan 2]. Available at: https://www.wsdot.wa.gov/environment/technical/disciplines/wetlands/policies-procedures/recon-assess

https://usace.contentdm.oclc.org/digital/collection/p266001coll1/id/4530

http://directives.sc.egov.usda.gov/OpenNonWebContent.aspx?content=37808.wba%20

http://directives.sc.egov.usda.gov/OpenNonWebContent.aspx?content=37808.wba%20

http://agacis.rcc-acis.org/

http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx

http://rsgisias.crrel.usace.army.mil/NWPL/

http://www.usace.army.mil/Portals/2/docs/civilworks/regulatory/reg_supp/west_mt_finalsupp.pdf

http://www.usace.army.mil/Portals/2/docs/civilworks/regulatory/reg_supp/west_mt_finalsupp.pdf

https://www.wsdot.wa.gov/environment/technical/disciplines/wetlands/policies-procedures/recon-assess

https://www.wsdot.wa.gov/environment/technical/disciplines/wetlands/policies-procedures/recon-assess

Springbrook Bank Unit C February 2020 Wetland Delineation Report Update

Appendix A —Wetland Determination Data Forms Wetland Delineation Data Forms for: W1-SP1 W1-SP2 W1-SP3 W1-SP4 Wetland polygons, sampling point locations, and wetland names shown in Figure 2.

US Army Corps of Engineers (WSDOT Adapted Form) Western Mountains, Valleys, and Coast – Version 2.0

Project/Site: City/County: Sampling Date:

Applicant/Owner: State: Sampling Point:

Investigator(s): Section, Township, Range:

Landform (hillslope, terrace, etc.): Local relief (concave, convex, none): Slope (%):

Subregion (LRR): Lat: Long: Datum:

Soil Map Unit Name: NWI Classification:

Are climatic / hydrologic conditions on the site typical for this time of year? (If no, explain in Remarks.)

Are Vegetation , Soil , or Hydrology significantly disturbed? Are "Normal Circumstances" present?

Are Vegetation , Soil , or Hydrology naturally problematic? (If needed, explain any answers in Remarks.)

Remarks:

Dominance Test worksheet:Tree Stratum (Plot size: )1. (A)2.3. (B)4.

= Total Cover (A/B)Sapling/Shrub Stratum (Plot size: )

2.3. OBL species x 1 =4. FACW species x 2 =5. FAC species x 3 =

= Total Cover FACU species x 4 =Herb Stratum (Plot size: ) UPL species x 5 =1. Column Totals: (A) (B)

4. Hydrophytic Vegetation Indicators:5. 1 - Rapid Test for Hydrophytic Vegetation6. 2 - Dominance Test is >50%7. 3 - Prevalence Index is ≤3.0¹8. 4 -9.

10. 5 - Wetland Non-Vascular Plants¹11. Problematic Hydrophytic Vegetation¹ (Explain)

= Total CoverWoody Vine Stratum (Plot size: )

2.

Remarks:

WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region

000 Springbrook Bank Unit C Renton/King 4/3/2019

WSDOT WA W1-SP1

Woodinville silt loam PFO

SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc.

Hydrophytic Vegetation Present?Is the Sampled Area within a Wetland?

Hydric Soil Present?Wetland Hydrology Present?

Tatiana Dreisbach, Amanda Mintz T23N, R4E, S25

depression concave 5

A 47.451 -122.238 NAD83HARN

Preceding rainfall was light with drier than normal conditions for three months leading up to this delineation (Appendix B-1 and B-2).

VEGETATION – Use scientific names of plants.

Absolute % Cover

Dom. Sp.?

Relative % Cover

Indicator Status20ft x 20ft Number of Dominant Species

That Are OBL, FACW, or FAC: 4Populus balsamifera

Total Number of Dominant Species Across All Strata: 4Salix sitchensis 10 N 12.5 FACW

50 Y 62.5 FACAlnus rubra 20 Y 25.0 FAC

100.0%8015ft x 15ft

1. Lonicera involucrata 20 Y 39.2 FAC Prevalence Index worksheet:

Percent of Dominant Species That Are OBL, FACW, or FAC:

Rosa nutkana 20 Y 39.2 FAC Total % Cover of: Multiply by:Cornus alba 5 N 9.8 FACW 0 0

51 1 45ft x 5ft 0 0

40Sambucus racemosa 1 N 2.0 FACU 110 330Physocarpus capitatus 5 N 9.8 FACW 20

Prevalence Index = B/A = 2.855

3742.

131

3.

Morphological Adaptations¹ (Provide supporting data in Remarks or on a separate sheet)

¹Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic.5ft x 5ft

Hydrophytic Vegetation Present?

= Total Cover% Bare Ground in Herb Stratum 100

1.

Yes NoYes NoYes No Yes No

Yes No

Yes No

Yes No


Sampling Point:

Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.)

¹Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. ²Location: PL=Pore Lining, M=Matrix.Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils³:

Restrictive Layer (if present):Type:Depth (inches): Hydric Soil Present?

Remarks:

Wetland Hydrology Indicators:Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required)

MLRA 1, 2, 4A, and 4B) 4A, and 4B)

Field Observations:Surface Water Present? Depth (inches):Water Table Present? Depth (inches):Saturation Present? Depth (inches): Wetland Hydrology Present?(includes capillary fringe)Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available:

Remarks:

SOIL W1-SP1

Depth (inches)

Matrix Redox FeaturesColor (moist) % Color (moist) % Type¹ Loc² Texture Remarks

2.5Y 6/2 2

C M Silt Loam concentration is prominent

10YR 6/4

0-1 2.5Y 3/1 88 7.5YR 4/6 5

D M

5 C M concentration is prominent

7.5YR

1-4 2.5Y 5/2 75 10YR

4/4 5 C PL concentration is prominent

20 C M Clay Loam concentration is prominent4/6

7.5YR

4-16 2.5Y 5/2 90 7.5YR

3/4 5 C PL concentration is prominent

5 C M Clay Loam concentration is prominent4/6

³Indicators of hydrophytic vegetation and wetland hydrology must be present, unless disturbed or problematic.

4"

HYDROLOGY

9"

Histosol (A1)Histic Epipedon (A2)Black Histic (A3)Hydrogen Sulfide (A4)Depleted Below Dark Surface (A11)Thick Dark Surface (A12)Sandy Mucky Mineral (S1)Sandy Gleyed Matrix (S4)

Sandy Redox (S5)Stripped Matrix (S6)Loamy Mucky Mineral (F1) (except MLRA 1)Loamy Gleyed Matrix (F2)Depleted Matrix (F3)Redox Dark Surface (F6)Depleted Dark Surface (F7)Redox Depressions (F8)

2 cm Muck (A10)Red Parent Material (TF2)Very Shallow Dark Surface (TF12)Other (Explain in Remarks)

Surface Water (A1)High Water Table (A2)Saturation (A3)Water Marks (B1)Sediment Deposits (B2)Drift Deposits (B3)Algal Mat or Crust (B4)Iron Deposits (B5)Surface Soil Cracks (B6)Inundation Visible on Aerial Imagery (B7)Sparsely Vegetated Concave Surface (B8)

Water-Stained Leaves (B9) (except

Salt Crust (B11)Aquatic Invertebrates (B13)Hydrogen Sulfide Odor (C1)Oxidized Rhizospheres along Living Roots (C3)Presence of Reduced Iron (C4)Recent Iron Reduction in Tilled Soils (C6)Stunted or Stressed Plants (D1) (LRR A)Other (Explain in Remarks)

Water-Stained Leaves (B9) (MLRA 1, 2,

Drainage Patterns (B10)Dry-Season Water Table (C2)Saturation Visible on Aerial Imagery (C9)Geomorphic Position (D2)Shallow Aquitard (D3)FAC-Neutral Test (D5)Raised Ant Mounds (D6) (LRR A)Frost-Heave Hummocks (D7)

Yes No

Yes No

Yes NoYes NoYes No











Remarks:








2.

Remarks:



WSDOT WA W1-SP2

Woodinville silt loam upland





hillslope concave 10

A 47.451 -122.238 NAD83HARN



Absolute % Cover

Dom. Sp.?

Relative % Cover

Indicator Status20x20 Number of Dominant Species


Total Number of Dominant Species Across All Strata: 5Sorbus aucuparia 5 N 5.3 UPL

70 Y 73.7 FACAlnus rubra 20 Y 21.1 FAC

100.0%9515x15

1. Rosa nutkana 20 Y 30.8 FAC Prevalence Index worksheet:


Physocarpus capitatus 20 Y 30.8 FACW Total % Cover of: Multiply by:Cornus alba 20 Y 30.8 FACW 0 0

65 0 05x5 5 25

90110 330

Fraxinus latifolia 5 N 7.7 FACW 45


4452.

160

3.


¹Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic.5x5



1.


Yes No

Yes No

Yes No


Sampling Point:




Remarks:




Remarks:

SOIL W1-SP2

Depth (inches)


D M Clay Loam

3-16 2.5Y 5/3 90 10YR 3/4

0-3 2.5Y 4/2 95 2.5Y 5/2 5

10 C M Clay Loam concentration is distinct


Bottom layer is "too bright" to meet and indicator. It would need chroma 2 or less to meet F3.

HYDROLOGY









Yes No

Yes No

Yes NoYes NoYes No











Remarks:








2.

Remarks:



WSDOT WA W1-SP3

Puyallup fine sandy loam PFO






A 47.451 -122.234 NAD83HARN



Absolute % Cover

Dom. Sp.?

Relative % Cover



Total Number of Dominant Species Across All Strata: 4

60 Y 66.7 FACSalix sitchensis 30 Y 33.3 FACW

100.0%9015ft x 15ft



Lonicera involucrata 10 N 18.2 FAC Total % Cover of: Multiply by:Physocarpus capitatus 10 N 18.2 FACW 0 0

55 0 05ft x 5ft 0 0

90160 480

Cornus alba 5 N 9.1 FACW 45


5702.

Ranunculus repens 60 Y 100.0 FAC 205

3.


60 ¹Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic.5ft x 5ft



1.


Yes No

Yes No

Yes No


Sampling Point:




Remarks:




Remarks:

SOIL W1-SP3

Depth (inches)


13-16 2.5Y 5/2 80 7.5YR 4/6 20

Sandy Loam

6-13 10YR 4/1 95 2.5Y 4/3

0-6 10YR 3/2 100

C M Sandy Loam concentration is prominent

5 C M Sandy Loam concentration is distinct


12

Sample point taken very near wetland boundary where saturation occurs at 12 inches. Climactic conditions for March were drier than normal. In a period with normal precipitation, it is likely "A hydrology inducators" would be present closer to the soil surface at this time of year.

HYDROLOGY









Yes No

Yes No

Yes NoYes NoYes No











Remarks:








2.

Remarks:



WSDOT WA W1-SP4

Puyallup fine sandy loam upland






A 47.451 -122.234 NAD83HARN



Absolute % Cover

Dom. Sp.?

Relative % Cover



Total Number of Dominant Species Across All Strata: 3

80 Y 100.0 FAC

100.0%8015ft x 15ft



Physocarpus capitatus 10 Y 22.2 FACW Total % Cover of: Multiply by:Lonicera involucrata 5 N 11.1 FAC 0 0

45 0 05ft x 5ft 0 0

20115 34510


3652.

125

3.


¹Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic.5ft x 5ft



1.


Yes No

Yes No

Yes No


Sampling Point:




Remarks:




Remarks:

SOIL W1-SP4

Depth (inches)


Sandy Loam

6-12 10YR 4/2 90 10YR 4/3

0-6 2.5Y 3/2 100

10 C M Sandy Loam concentration is faint


rock layer12

Concentration is faint and therefore the soil does not meet indicator F3 and also indicates that wetland hydrology is not likely present long enough in this location to create the anaerobic conditions that result in evidence of hydric soil indicators at the wetland boundary.

HYDROLOGY









Yes No

Yes No

Yes NoYes NoYes No


Appendix B — Precipitation Data Appendix B-1. Comparison of Observed and Normal Precipitation (NRCS 2015) Monthly precipitation data for Kent, Washington.

Long-term rainfall recordsa

Month 3 yrs. in 10 less

than Average

3 yrs. in 10 more

than Rain falla

Condition dry, wet, normalb

Condition Value

Month weight value

Product of previous two

columns

1st prior month March 3.15 4.13 4.81 1.15 dry 1 3 3

2nd prior month February 2.89 4.42 5.31 4.01 normal 2 2 4

3rd prior month January 3.98 5.40 6.33 3.34 dry 1 1 1

Sum 8 aNRCS 2019 b Conditions are considered normal if they fall within the low and high range around the average.

Note: If sum is Condition value: 6 - 9 then prior period has been Dry (D) =1 drier than normal Normal (N) =2 10 - 14 then period has been Wet (W) =3

normal 15 - 18 then period has been wetter than normal

Conclusions: Drier than normal precipitation conditions were present prior to the field visits.


Appendix B-2. Daily Precipitation 10 days preceding field work, Kent, Washington

Daily precipitation data for Kent, Washington.

Date (2019)

Daily Precipitation (inches)a

Date (2019)

Daily Precipitation (inches)a

March 8 T March 21 0.00

March 9 0.00 March 22 0.00

March 10 0.00 March 23 0.00

March 11 0.00 March 24 0.00

March 12 0.72 March 25 0.05

March 13 0.00 March 26 0.01

March 14 0.01 March 27 0.00

March 15 0.00 March 28 0.15

March 16 0.00 March 29 0.00

March 17 0.00 March 30 0.01

March 18 0.00 March 31 M

March 19 0.00 April 1 0.00

March 20 0.00 April 2 0.00

10-Day sum prior to March 18 site visit 0.73

10-Day sum prior to March 26 site visit 0.05

10-Day sum prior to April 3 site visit 0.22 a NRCS 2019

“T” values indicate a TRACE value was recorded. “M” values indicate missing data.

Conclusions: Light precipitation was recorded in the ten days preceding field work.

2019 wetland monitoring report...mar 31, 2020 · this report summarizes final-year (year-10)...

Documents