HomeMy WebLinkAbout02956 - Technical Information Report ,
American Engineering Corporation
=- --= Engineers � Pianners • Surveyors — _
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a Plat of"The Vineyards"
N City of Renton
Stormwater Design
Technical Information Report
Project Site Location:
550 Union Avenue NE
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�� August l 6, 2001
Revised October S, 2001
prepared for:
Consultin� En�ineev�s
Belmont Hoines, Inc.
Creative Solutlons. . . P.O. Box 2401 �'
Sll�c'�f��t'Set'�Ic'c'. Kirkland, WA 98083-2401
AEC Job #9838
_�,�� � � 95�
Plat of "The Vineyards"
City of Renton
Stormwater Design
Technical Information Report
Project Site:
550 Union Avenue NE
August 16, 2001
Revised October S, 2001
Prepared for-:
Belmont Homes, Inc.
P.O. Box 2401
Kirkland, WA 98083-?-�0]
(206) 714-6���
Prepared f��,
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American Engineering Corporation .:.��.� R
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4032 148`h Avenue NE �.�" ,� � ��'°" �
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Redmond, WA 98052 r-,:�! r ' �• -�f
(425) 881-7430 - '��'� � ` �.
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AEC Job #9838 '
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Stormwater Technical Information Report,Rei�ision �l AECJob #9838
The Vineyards October 5, 1001
Stormwater Design Technical Information Report
Plat of"The Vineyards"
City of Renton
Table of Contents
Section Page Numbers
Section I: Project Overview 1 — 5
Section II: Preliminary Conditions Summary 6— 11
Section III: Offsite Analysis 12
Section IV: Detention and Water Quality Analysis and Design 13-15
Section V: Conveyance System Analysis and Design 16-20
Section VI: Special Reports and Studies — Resource Review 21
Section VII: Basin and Community Plan Areas 21
Section VIII: Other Permits 21
Section IX: Temporary Erosion and Sedimentarion Control 21
Section X: Maintenance and Operations Manual 37-44
List of Figures
Figure 1: Technical Information Report Worksheet (TIR) 2 — 4
Figure 2: Vicinity Map 5
Figure 3A: Existing Drainage Basin Map 7
Figure 3B: Developed Drainage Basin Map 8
Figure 4: SCS Soils Map 9
Figure 5: Assessor's Map 10
Figure 6: City of Renton Zoning Map 11
Figure 7: Precipitation for Mean Annual Storm- Isopluvials 15
� Appendices:
Appendix A: King County Runoff Time Series Inputl0utput Data
Appendix B: Wetland Report
Stormwater Technica!Inforn�ation Report,Revision#I AEC Job#9838
The Vineyards October S,2001
Section I: Project Overview
The proposed project site is located in the SW '/4, Section 10, Township 23N, Range SE, in the City of
Renton, Washington as shown in Figure 2: Vicinity Map. The 7.3-acre site is comprised of six separate
tax parcels. Figure 5: Assessor's Map identifies the parcels within the proposed project site. The
project site is zoned Residential-10 units per acre (R-10) as shown in Figure 6: Zoning Map.
The overall site is generally flat with a 1% to 5% slope to the west and south. Vegetation consists of
grasses, shrubs, vines and medium diameter second growth conifers. There are also a few deciduous
trees on the property. The site contains 5 existing single-family residential homes that will be
demolished as part of this proposed development. The site is bordered on the west by a Category 2
wetland of which approximately 0.15 acres is contained within the project site. Please refer to Figure
3A: Existing Drainage Basin Map. Various historic disturbances to the Category 2 ��vetland have
occurred and have been documented by the City of Renton. There is also a 3,928 square foot category 3
wetland near the southeast corner of the project site that will be filled as part of this project. A U.S.
Army Corps of Engineers JAR.PA has been made. All on-site soils are Alderwood gravelly sandy loam,
AgC, "Type C" (till), as indicated by the SCS soils map, Figure 4.
The proposed development will create 42 single-family residential lots as shown in Figure 3B:
Developed Drainage Basin Map. Access to the new lots is proposed via approximately 1,400 feet of
public road. The roads are proposed to be 32 feet wide and surfaced with asphalt pavement. Cement
concrete curb and gutter are proposed to collect storm��rater runoff. Additionally, 5-foot wide cement
concrete sidewalks on both sides of the street are proposed for pedestrian access through the project site. �
Other improvements may include some shared driveways, individual driveways, and public open space. I
The proposal includes wetland buffer zones of 25 feet on the north end of the project site and a 50—foot
wide buffer for the portion of the same wetland near the south end of the site. The 25—foot buffer zone
has previously been established for the northern portion of the wetland. j
Stormwater from the developed site will be collected in catch basins, conveyed in underground pipes and I
routed to one underground detention vault near the south end of the site. The underground vault will
provide both the necessary water quality treatment and detention required for this proposed project. The
discharge from the detention structure at a controlled rate of release will be allowed to flow into the
Category 2 wetland. The storm detention vault will contain a dead storage volume sized as necessary for
water quality treatment.
Public water distribution and sanitary sewage collection systems will be constructed to serve the 42
single-family residential homes proposed by this project.
King County Department of Development and Environmental Services
TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
Part 1 PROJECT OWNER AND Part 2 PROJECT LOCATION AND
PROJECT ENGINEER DESCRIPTION
Project: Project Name:
Owner Belmont Homes. Inc. The Vinevards
Address: P.O. Box 2401 Location:
Kirkland. WA 98083-2401 Township 23N
Phone: Range 5E, W.M
�206)714-6706 .............Section 10
Project Engineer:
Cheryl Girard, PE _
i Company: American EnaineerinQ Corp
; Address/Phone: 4032 148t''Ave NE
I
: Redmond WA 98052 Tel. 425-881-7430 '
Part 3 TYPE OF PERMIT Part 4 OTHER REVIEWS AND PERMfTS
APPLICATION
� Subdivison DFW HPA Shoreline Management
Short Subdivision COE 404 Rockery
Grading DOE Dam Safety 0 Structural Vaults
Commercial
FEMA Floodplain Other
Other ❑X COE Wetlands
Part 5 SITE COMMUNITY AND DRAINAGE BASIN
Community
Renton
Drainage Basin
Maplewood Creek into Cedar River.
Part 6 SiTE CHARACTERISTICS
River Floodplain
� Wetlands I
Stream Seeps/Springs ',
Critical Stream Reach High Groundwater Table �I
� Depressions/Swales
Groundwater Recharge II
Lake
Other
Steep Slopes
FIGURE 1
2
Part 7 SOILS
I Soil Type Slopes Erosion Potential Erosive Velcoties
AA C 2-5% Low Low
Additional Sheets Attached
Part 8 DEVELOPMENT LIMITATIONS
REFERENCE LIMITATIONlSITE CONSTRAINT
Ch.4—Downstream Analvsis �
.
I
Additional Sheets Attached
Part 9 ESC REQUIREMENTS
MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS
DURING CONSTRUCTION AFTER CONSTRUCTION
❑X Sedimentation Facilities 0 Stabilize Exposed Surface
� Stabilized Construction Entrance � Remove and Restore Temporary ESC Facilities
0 Perimeter Runoff Control Clean and Remove All Silt and Debris
Clearing and Graing Restrictions � Ensure Operation of Permanent Facilities
Cover Practices Flag Limits of SAO and open space
❑X Construction Sequence preservation areas
Other Other
FIGURE I
Part 10 SURFACE WATER SYSTEM
Grass Lined Tank Infiltration Method of Analysis
Channel � Vault
Depression
� Pipe System Energy Dissapator Flow Dis ersal Compensation/Mitigati
Open Channel p on of Eliminated Site
Wetland Waiver Storage
Dry Pond Stream
0 Wet Pond Regional
Detention
Brief Description of System Operation The site will have a Qiped collection system to on
underground vault w/discharge to wetlands. Water qualitv is achieved bv dead storaqe in vault.
Facility Related Site Limitations .
Reference Facility - Limitation
Pa�# 11 STRUCTURAL ANALYSIS Part 12 EASEMENTS/TRACTS
❑x Cast in Place Vault Drainage Easement
Retaining Wall Access Easement
Rockery> 4' High Native Growth Protection Easement
Structural on Steep Slope Tract
Other Other
Part 13 SIGNATURE�F PROFESSIONAL ENGINEER
I or a civil engineer under my supervision my supervision have visited the site. Actual site
condi � s as observed were incorporated into this worksheet and the attachments. To the best of
my no dge the informati n provided here is accurate. i
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Stormwater Technica!hzformation Report,Revision#1 .9ECJob#9838
The 6inetiards October 5,2001 i
• � 'i
Section II. Preliminar� Conditions Summary ,
E�isting Site Conditions �
The site contains five single-family residential homes and the remainder of the property is
vacandundeveloped. The City of Renton identifies the site as being located in a Zone 2 Aquifer
Protection Area. T'he City of Renton Storm System Inventory Book indicates that the site is located in
the Maplewood Creek sub-basin of the Cedar River drainage basin. There are three wetlands within the
project site as described previously and delineated in Figure 3A: Existing Drainage Basin'�iap. City
of Renton sensitive area maps do not identify additional sensitive areas within the project site. The
project site is in map number 53033C0327 D of Federal Emergency Management Agency(FEMA) and -
is identified as being]ocated in Zone X. Zone X is identified as areas determined to be outside 500-Year
floodplain.
The overall site topography is flat with slopes ranging from approximately 1.8 to 5.0 percent. The '
e�isting site topography indicates that runoff is currently directed to the wetlands within the project site
�•ia overland sheet flow. Field investigation has confirmed that some flows enter the wetlands at the
northwest corner of the site from neighboring properties to the north. Very little, if any, offsite flow
from the east, northeast or south enters the site. Properties to the west and south of the subject property
consist of older single-family residential homes.
Ground cover includes wetland vegetation, both sparsely spaced and clustered trees, bushes/shrubs, and
tall grass. The existing houses are accessed from existing public roadwa}�s from various locarions via
gravel driveways. Site soils are Alderwood gravelly sandy loam (AgC) till, see Figure 4: SCS Soils
Map.
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Plat of "The Vineyards TIR o 9838
Figure 3B-Developed Drainage Basin Map 0 1 1
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Plat of�`The Vineyards TIR i
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Plat of"The Vineyards TIR �O2 _
Figure 5 —Assessors Map 1" = 100' �,Q.QB ��
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Plat of"The Vineyards TIR �" „�a" E6 �
Figure 6 - City of Renton Zoning Map 10 T23N R5E W 1/2 �
' Il
Stormwater Teclu�rcalln�ormation Report, Revision#/ AECJob#9838
The Vinel'ards October.i, �001
Section III: Offsite Analysis
Existing Upstream Flow Path
Offsite flow entering the site includes storm«�ater drainage system runoff from NE 6`h Place and the
discharge from the detention pond to the north into the wetlands that picks up runoff from the
neighboring properties. Storm water runoff from NE 6`h Place is conveyed to the onsite Wetland via
conventional conveyance system.
Storm water runoff from the piping system in Union Avenue NE does not appear to contribute to this
project site. Instead, the flows are conveyed by the piping system past the site under Union Avenue NE
to the south.
Existing Downstream Flow Path
All onsite storm water runoff is directed to the onsite wetlands by the e�isting topography via overland
sheet flow. The large category 2 wetland drains across the northern portion of the project, exits the site
and flows south through two existing 18-inch offsite pipes crossing under the existing driveways. The
flow then re-enters the project site in the southwest portion of the property and then enters a 24—inch
pipe that drains the�;�etland to the existing storm drainage system under Union Avenue NE. The
existing drainage system flows south under Union Avenue NE and the properties to the east. The system
crosses under NE 4`h Avenue and the parking lot of a commercial establishment. Storm water then
outfalls into a wetland, located to the east of a commercial establishment. A channel is created by the
runoff along the west and southwest sides of the wetland located east of the commercial site. City of
Renton Storm System Inventory Book indicates that the runoff is detained in what appears to be a
regional detention area located north ofNE lst Place. Flow is released from the regional facility and
then crosses beneath Bremerton Place NE and then outfalls into Maplewood Creek. Maplewood Creek
is identified as the sub-basin for the project site in the immediate vicinit��. Maple«ood Creek flo�-s into
�� '�- the Cedar Ri�-er.
Proposed Downstream Flov�� Path
The proposed downstream flow path will not be altered by�this proposal. \o surface ���ater flo«� rate
increase or decrease is anticipated do��mstream as a result of this proiect.
1Z
Stormwater Technica!Information Reporl,Revision Yrl AECJob#9838
The Vineyards October S. 2001
Section IV: Detention and Water Quality Analysis and Design
Storm water detention for this project is to be provided in a single onsite detention system. Storm water
flows for existing and proposed site conditions are presented to verify adequacy of the proposed
detention,water quality and conveyance system. Flows have been modeled using the King County
Runoff Time Series (KCRTS) software program.
The City of Renton Storm Drainage Design Standards requires Level II detention and water quality
design for all surfaces subject to vehicular traffic, using the 1998 King County Surface Water Design
Manual (KCSV��DM) standards. In addirion, the City of Renton prefers infiltration as the method of
storm water outfall if project site conditions allow. Due to the elevations of the existing utilities to
which the project is required to connect, a majority of the site will be raised in elevation by
approximately 2 feet. By placing 2 feet of fill on the project site and having to properly compact it, the �
use of individual infiltration systems for rooftop downspouts is not feasible. In addition to the roadways `
and sidewalks, the rooftop drainage must also be directed to and treated within the proposed storm
drainage detention and water quality facility. The outfall from the proposed detention and water quality
facility will ultimately release treated flow into the existing type 2 wetland along the east side of Union
Ave.NE. The flow from this project will then infiltrate into the ground beneath the wetland as much as
natural conditions will allow.
Existing Site Hydrology
The following assumptions and site parameters were used in analyzing the existing site hydrology to the
combined detention and wetvault:
Total Area = 7.3 Acres
Bl pass:
1.61 AC (wetlands and other areas to remain undisturbed)
Site: �
Impervious =0.45 AC (existing gravel roads, homes) �
Till Forest=2.69 AC
Till Pasture = 2.55 AC
Total = 5.69 AC to vault I
Developed Site Hydrology
The following assumptions and site parameters were used in analyzing the developed site hydrology to
the combined detention and «�etvault: '
Total Area = i 3 Acres
Bypass vaulr: 'I
1.61 AC (wetlands and other areas to remain undisturbed) �,
To vault: �
�:, Impervious=2.67 AC (proposed roads,homes)�-- '
Till Grass=2.93 AC
Till Pasture=0.090 AC (wetland conversion SE corner site)
Tota1 = 5.69 AC to vault
_
�3
Stormwaler Technical Information Report,Revision#1 AECJob#9838
The Vineyards October 5,2001
Flow Quantity Control
The 1998 KCSWDM Level II flow control standard requires that durations of high flows will be
maintained at their predeveloped levels for all flows greater than one-half of the 2-year peak flow up to
the 50-year peak flow. The live storage volume required is 45,300 CF; the live storage volume provided
is 45,300 CF. Flow control will be achieved using the live storage volume in the proposed detention
vault,with outflow from the vault regulated via a riser-type control structure with two orifices, located in
a T-2 catch basin just south of the vault. Please see Appendix A for KCRTS documentation of the Level
II flow control standard modeling.
Flow Quality Control
The basic water quality menu treatment requirement will be met by utilizing dead storage in the
proposed detention vault. Due to the relatively flat topography and limited surface area after proposed
roadways and future homes are constructed, surface treatment for water quality through means of
vegetated bio-filtration is not f�asible; individual on-site infiltration or surface dispersal is also
unfeasible due to limited surface area. All flows requiring water quality treatment will be conveyed to
the proposed vault. The proposed vault is expected to remove at least 80 % of TSS. Please see
Engineering plans sheet 5/12 (detached) for vault details.
Basic Wetpond Design, KCSV��DM Sec. 6.4.1.1
V�'etpool volume factor,f= 3 �
Runoff from mean annual storm,R=0.47" (see Figure 7) �
Runoff from mean annual storm for developed site, Vr
Vr= (0.9Ai+ 0.25Atg+ O.lOAtf+ O.OIAo)x (R/12)
Ai=2.67 AC �'
Atg= 3.o2AC ;:��� ��� ��s �- � 2 g�� ��
A�=o.000 ac
Ao=0.000 AC
Vr= [(0.9 x 2.67 x 43,560) + (0.25 x 3.02 x 43,560)] x 0.47/12
Vr=5,388 cf ✓ ���
Wetpool volume required, Vb y� �1 x �`��t y Z�
Vb =.fVr= 3 x 5,388 = 16,164 cf required wetvault volume �
�� '��
Proposed weri�ault -'
Volume 15` cell=(392.91 — 389.91)'D x 42'L x 46.3'W=5,830 cf
Volume 2"d cell =(392.91 —38991)'D x 98'L x 46.3'W= 13,610 cf �,
Total proposed volume = 19,440 cf cf> 16,164 cf required
%volume 151 ce11 = 5,830/19,440 =30.0 %OK(>25%<35% req'd)
r_ ;
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II
6.4.1 WE�ONDS—BASIC AIv'D LARGE—METHODS OF ANALYSIS '
FIGURE 6.4.1 A PRECIPTTATTON FOR VIEA.N A?�1NUAL STORM IN INCHES (FEE'I')
I
ST 1.0/ �,p, 1 2
ST 1.C � 0.8 L.�. 0.9 L'p' 1.0 I
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� Incorporated Area � ---- ` a
�� RiveNLake 0.�"" �
— Major Road (C.�3 9' ) p,�2�� `'� � _. �'�
� �'� �``-^" 0.o"5" `
NOTE:Areas east of the eastemmost isoplwial should use 0.65 �0.0 4 3 'p y o„ � � �0.0 54' )
inches unless rair�fall data is avaiiable for the location cf Interest �C ,�47 . �
Z'The mean annual stortn is a conceotual stortn found
�by dividing V�e anrwal ptedpnation by the total number
W sbrm events per year
Plat of"The Vineyards TIR
Figure 7: — Precipitation for Mean Annual Storm :
:998 Surface Water Desi�n Manual 9/1198
_ �
— - -
Stormwater Technical Information Report,Revision#1 AECJob#9838 I
The Vineyards October S,2001
I
Section V: Conveyance System Analysis and Design I
T'he proposed stormwater conveyance system was analyzed for capacity to convey and contain the 25- II
year,24-hour peak flow. Peak flow rates obtained using the rational method were used in conjuntion ',
with the King County Backwater Program (KCBV�to predict headwater elevations at each catch basin. ',
Based on the results of the KCBW analysis program,none of the catch basins will overflow during the ,
25-year, 24-hour storm event. �
Overflow from the 100-year, 24-hour event should not create or aggravate a severe flooding problem, as
overflow will infiltrate into the ground beneath the category II wetland (along the east side of Union
Ave.NE) as much as natural conditions will allow.
Conveyance system sizing analysis and design calcularions are provided on the following pages.
� �I
�� ��
PIPE SIZING CHART, 25-YEAR CONVEYANCE DESIGN, THE VINEYARDS PLAT AEC#9838, 10-03-01
� TRIB TOTAL PIPE PIPE PIPE
" AREA AREA Tc Q Design V Design SIZE SIOPE LENGTH Qfull UPSTREAM DOWNSTREAM
FROM TO (AC) (AC) "C" (min) a25 bss Pss �zs I (cfs) (fps) (in) "N" (%) (ft) (cfs) RIM(ft) INVERT(ft)RIM(ft) INVERT(ft)
CB10 C89 0.519 0.519 0.68 6.3 2.66 0.65 3.4 0.804 2.734 0.965 1.23 12 0.012 0.51 759 2.76 404.19 400.45 405.98 399.64
CB9 CB8 0.704 1.223 0.68 6.3 2.66 0.65 3.4 0.804 2.734 2.274 1.85 15 0.012 0.51 243 5.01 4U5.98 399.64 405.78 39A.41
CBB CB7 1.208 2.431 0.68 6.3 2.66 0.65 3.4 0.804 2J34 4.519 3.68 15 0.012 0.51 128 5.01 405.78 398.41 404.69 397.76
CB7 CB6 0.427 2.858 0.68 6.3 2.66 0.65 3.4 0.804 2J34 5.313 4.33 15 0.012 0.51 742 5.07 � 404.69 397J6 403.46 397.02
C86 C65 0.724 3.582 0.68 6.3 2.66 0.65 3.4 0.804 2.734 6.659 3.77 18 0.012 0.51 39 8.15 403.46 397.02 403.42 396.82
C85 CB4 0.318 3.9 0.68 6.3 2.66 0.65 3.4 0.804 2.734 7.250 4.10 18 0.012 7.1 140 11.87 403.42 396.82 401.92 395.27
CB4 CB4B 0.709 4.609 0.68 6.3 2.66 0.65 3.4 0.804 2.734 8.569 2.73 24 0.012 1.87 145 33.6 401.92 395.27 401.7 392.55
CB4B VAULT 0.426 5.035 0.68 6.3 2.66 0.65 3.4 0.804 2.734 9.360 2.98 24 0.012 1.87 5 33.6 401.7 392.55 401.7 392.46
VAUIT C83 1.42 1.81 12 0.012 1 5 3.87 401.7 392.91 401.7 392.86
� CB3 CB1 1.42�' 1.81 12 0.012 0.25 177 1;94 407.7 392.86 396 392.41
CB1 OUTFALL 1.42 1.81 12 0.012 0.5 20 2.74 396 392.37 392.21
�','�p°f'^�,xv°°"r-�'!7�`3f�`S'^"�+�^ �...� , , _, . , . .. ,. . �
CB2 C82B 0.655 0.655 0.68 6.3 2.66 0.65 3.4 0.804 2.734 1.218 1.55 12 0.012 0.5 150 2.74 400.1 397.22 401.36 396.47
CB28 CB2C 0 0.655 0.68 6.3 2.66 0.65 3.4 0.804 2.734 1.218 1.55 12 0.012 0.38 125 2.39 407.36 396.4�' 401 396
CB2C VAUIT 0 0.655 0.68 6.3 2.66 0.65 3.4 0.804 2.734 1.218 1.55 12 0.012 1 5 3.87 401 396 401.7 395.95
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BACKWATER COMPUTER PROGRAM FOR PIPES
Pipe data from file:9838bwa.bwp
Surcharge condition at intermediate junctions
Tailwater Elevation:399.6 feet
Discharge Range:9.36 to 9.36 Step of 1. [cfs]
Overflow Elevation:404.19 feet
Weir:NONE
Upstream Velocity:l. feet/sec
PIPE N0. 1: 5 LF - 24"CP @ 1.80� OUTLET: 392.46 INLET: 392.55 INTYP: 5
JUNC N0. 1: OVERFLOW-EL: 401.70 BEND: 90 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.09
Q{CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
*********,r**,r*,r******�k#-***********.*********x*********************************�*
9.36 7.31 399. 86) * O..OT2 1.10 0.74 7.14 7.14 7. 06 7.31 1.65
PIPE NO. 2 : 145 LF - 2�#"CP @ 1.88� OUTLET: 392 .55 INLET: 395.27 INTYP: 5
JUNC N0. 2 : OVERFLOW-EL: 401.92 BEND: 90 DEG DIA/WIDTH: 4.0 Q-RATIO: 0 .18
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
**,r:,r*****************,r*�k x�***,r,r,r*******************,r**********************,r**v�*
8.59 5.08 400.35 * 0.012 1.05 0.69 7.31 7.31 4 .78 5.08 1.64
PIPE NO. 3 : 140 LF - 18"CP @ 1.11$ OUTyET: 395.27 INLET: 396.82 INTYP: 5 !
JUNC NO. 3 : OVERFLOW-EL: 403.42 BEND: 90 DEG DIA/WIDTH: 4 .0 Q-RATIO: 0.09 �
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
*******************************************************************************
7.28 4.58 401.40 * 0.012 1. 05 0.85 5.08 5 .08 4 .10 4.58 1.77
PIPE N0. 4: 39 LF - 18"CP @ 0.51� OiTTLET: 396.82 INLET: 397.02 INTYP: 5
NNC NO. 4 : OVERFLOW-EL: 403.46 BEND: 0 D�G DIA/WIDTH: 4 .0 Q-RATIO: 0.25
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
*,r************,r**********,r,r******,r*,r*******.*********************,r*********,r**�
6.68 4 .62 401.64 * 0.012 1.00 1.04 4 .58 4 .58 4 .52 4 .62 1.34
PIPE N0. 5: 142 LF - 15"CP C� 0.52� OUTLET: 397. 02 INLET: 397.76 INTYP: 5
JUNC NO. 5: OVERFLOW-EL: 404.69 BEND: 0 DEG DIA/WIDTH: 4 .0 Q-RATIO: 0.18
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
*******************************************************************************
5.34 4 .97 4C2 .73 * 0.012 0 . 94 1. 11 4 .62 4 .62 4 .71 4 . 97 1 .40
PIPE NO. 6: 128 LF - 15"CP @ 0.51$ OUT:.,ET: 397.76 INLET: 398 .41 INTYP: 5
JUNC N0. 6: OVERFLOW-EL: 405.78 BEND: 0 DEG DIA/WIDTH: 4.0 Q-RATIO: 0.99
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
********************,r,r,r**,r*************�r*****************************�*****w**
IB�
�--
4 .53 5.15 403.56 * 0.012 0.87 0.94 4.97 4.97 4 .86 5.15 1.36
PIPE N0. 7: 243 LF - 15"CP C�? 0.51� OLTTLET: 398.41 INLET: 399.64 INTYP: 5
JUNC N0. 7: OVERFLOW-EL: 405.98 BEND: 0 DEG DIA/WIDTH: 4 .0 Q-RATIO: 1.36
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN T'W DO DE HWO HWI
*****************************,r***************************,r*********************
2.27 4.26 403 .90 * 0.012 0.61 0.60 5.15 5.15 4.19 4.26 0.86
PIPE NO. 8: 159 LF - 12"CP @ 0.51� OUTLET: 399.64 INLET: 400.45 INTYP: 5
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
*********************************,r*********************************************
0.96 3 .58 404.03 * 0.012 0.42 0.41 4 .26 4.26 3 .56 3.58 0.56
� ��
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BACKWATER COMPUTER PROGRAM FOR PIPES
Pipe data from file:9838st.bwp
Surcharge condition at intermediate junctions
Tailwater Elevation:399.6 feet
Discharge Range:1.218 to 1.218 Step of 1. (cfs]
Overflow Elevation:400.2 feet
Weir:NONE
Upstream Velocity:l. feet/sec
PIPE N0. 1: 5 LF - 12"CP Q 1.00� OUTLET: 395.95 INLET: 396.00 INTYP: 5
JUNC NO. 1: OVERFLOW-EL: 401.00 BEND: 90 DEG DIA/WIDTH: 2 .0 Q-RATZO: 0.00
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
*******************,r*******�******x***************************,r*************x**
1.22 3 .68 399.68 * 0.012 0.47 0.39 3 .65 3 .65 3 .61 3.68 0.68
PIPE NO. 2: 125 LF - 12"CP @ 0.38� OUTLET: 396.00 INLET: 396.47 INTYP: 5
JUNC NO. 2 : OVERFLOW-EL: 401.36 BEND: 90 DEG DIA/WIDTH: 2 .0 Q-RATIO: 0 .00 '
Q(CFS) HW(FT} HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
***********,r********,r**********************************************************
1.22 3 .41 399.88 * 0.012 0.47 0.51 3 .68 3 .68 3 .34 3 .41 0.68
PIPE NO. 3 : 150 LF - 12"CP C� 0.50� OUTLET: 396.47 INLET: 397.22 INTYP: 5
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI !�
,r**************************,r*************************�*************************
1.22 2.85 400.07 * 0. 012 0.47 0.47 3 .41 3.41 2.81 2.85 0.65
I
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BACKWATER COMPUTER PROGRAM FOR PIPES
Pipe data from file:9838vt.bwp
Surcharge condition at intermediate junctions
Tailwater Elevation:393.5 feet
Discharge Range:1.42 to 1.42 Step of 1. (cfs]
Overflow Elevation:399.9 feet
Weir:NONE
Upstream Velocity:l. feet/sec
PIPE NO. 1: 20 LF - 12"CP @ 0.50� OUTLET: 392 .21 INLET: 392 .31 INTYP: 5
JUNC N0. 1: OVERFLOW-EL: 396.00 BEND: 45 DEG DIA/WIDTH: 2.0 Q-RATIO: 0.00
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
************************,r***x�****************************************.**********
1.42 1.27 393 .58 * 0.012 0.51 0.52 1.29 1.29 1.22 1.27 0.70
PIPE N0. 2 : 177 LF - 12"CP @ 0.25$ Oi7TLET: 392 .41 INLET: 392 .86 INTYP: 5
JUNC N0. 2 : OVERFLOW-EL: 401.70 BEND: 90 DEG DIA/WIDTH: 4 . 0 Q-RATIO: 0.00
Q(CFS) HW(FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
****,�**************************************************************************
1.42 1.04 393.90 * 0.012 0.51 0.64 1. 17 1.17 0. 94 1.04 0.75
PIPE NO. 3: 5 LF - 12"CP @ 1. 00$ OUTLET: 392 .86 INLET: 392 .91 INTYP: 5
Q{CFS) HW{FT) HW ELEV. * N-FAC DC DN TW DO DE HWO HWI
*****************,r***************,r*********************************************
1.42 1.06 393.97 * 0.012 0.51 0.42 1. 04 1.04 1. 00 1.06 0.71
, i
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Stormwater Tec/:nicallnjormation Report,Revision #1 AECJob#9838
The Vineyards October 5,1001
Section VI: Special Reports and Studies — Resource Review
�I The City of Renton records were researched to determine if any additional sensitive areas or aquifer
protection zones requiring special drainage design parameters existed on the project site. No additional
sensitive areas have been identified by available mapping or through field reconnaissance. Other
information determined throu h resource review is listed below:
g
The project is within the King County DNR"East Sanitary Sewer Interceptor District"
The project is within the City of Renton 565 water pressure zone with fire flow of 2500 to 4500 gpm
The project is within Aquifer protection Zone 2
Section VII: Basin and Community Plan Areas
`the project lies with the lower Cedar River Watershed.
The property is designated as Residential Options in the City of Renton Comprehensive Plan
The property is zoned R-10
Section VIII: Other Permits
The project received Land Use Approval on July 16, 2001. Please refer to the following pages for the
Findings and Recommendations of the Hearing Examiner. A Grading and Utility Pexmit is required for
construction of the proposed roadway and utiliries. A right-of-way use permit will be required to
connect to the existing water and sanitary sewer systems. A JARPA has been filed with the US Atmy
Corps of Engineers for the proposed filling of the small wetland near the SE corner of the project site. '
Separate Building permits will be required for the proposed detention vault, rockeries greater than 4 feet '
in height and each individual home as they are proposed to be constructed. We are not aware of any li
additional permits required for this project.
Section IX: Temporary Erosion and Sedimentation Control �,,
Temporary Erosion and Sedimentation Control for this project is proposed through the use of filter fabric ;
fence installation to protect the wetlands and adjacent properties from silt and sediment that may result '
from grading activities on this project site. A rocked temporary construction entrance is proposed to
prevent construction vehicle wheel tracking of earth from the project site. Please refer to sheet 3 of 13 �
for the proposed TESCP. Additional erosion and sedimentation control methods may be required by the
Ciry of Renton inspector if weather conditions dictate.
'�
?�
�:, :� ,��;. CITY OF RENTON
..� l -• �� Hearing Examiner
Jesse Tanner,Mavor
R����,��" Fred J.Kaufman
D'Uu 1 � Z�J��,
August 13, 200] p�,EqICAN Ey'���,==- -
CCP,°OAAi���''+
Robert P. Wenzl Elizabeth His�ins
President Planning/Building/Public �T�'orks Dept.
Belmont Homes, Inc. City of Renton
PO Box ?401 10>j S. Grady Way
Kirkland, WA 98083-2401 Renton, WA 980��
� RE: The Vineyards Preliminary Plat, LUA00-0?9.ECF,PP
Dear Mr. Werizl and Ms. Higgins:
This office has received two requests for reconsideration, one from staff and one from the
appficant, as well as a request from staff to clarify Condition Numbers � and 6. This office has
reviewed these requests.
This office completely sympathizes with the objective of providing affordable housing. $ut such
housing cannot be done at the expense of orderly development that meets code standards. The
proposed "�vide spot" in the road is not sanctioned an}�where in code. It is merely an expedient
circumvention of normal road building standards. It is completely inappropriate to rely more or
less on using some resident's private drivew�ay to facilitate a u-turn on a public street.
The lack of opposition to the proposal from the publi: is not demonstrative. There are a number
of improper design issues that would not affect the�eneral public, particularly, before the project
is inhabited. The consequences of this "turnaround"�;ould only be felt after the unorthodox
turnaround and repeated u-turns occurred on someone's private lot.
Both the applicant and staff sug�est that the propert}�west of the subject site will eventually be
platted allo��ing the road to be connected to Union Avenue NE, no timeframe exists and it could
be months or even years. It may not happen at all. The current gated, but defacto dead-end of
NE 6th off of Union could stay that way for a lon�time with no certainty that a public road
connection to Union would ever be created.
Similarly, an easement over a private, inhabited lot for a turnazound to serve an entire 42-lot plat
is inappropriate. Again, it may have to serve as an official turnaround or u-turn route for a long
time.
A temporary turnaround on Proposed Lot 14 would�vork in the interim as long as that lot is not
developed. Again, it is completely inappropriate to rely on a private lot's area for a needed
turnaround to accommodate the general public. This is not the instance of a small short plat
where interior lots need a hammerhead turnaround but a full plat. Therefore,Proposed Lot I4
should serve in its entirety as a turnaround,which could be abandoned when and if the property to
the west is actually subdivided, and a through road to Union is created. Once a through road is
created then Proposed Lot 14 could be developed with a single family home. The remainder of
the lot could be used as a temporary tot lot or picnic area.
�Vhile this would result in the.temporary loss of one lot from the proposed subdivision, it would
. � . _� _
_a. �
� , � ,�x
IQ"" �V o - _ ? 430- 51
not be a permanent loss since both the applicant and staff believe that the property to the west will
create the through link to Union in the future.
Therefore, Condition Number 3 shall be altered to read as follows:
3. A temporary hammerhead turnaround shall be constructed on Proposed Lot 14 and
Proposed Lot 14 shall not be developed with a single-family home until NE 6th
Street is connected to Union Avenue NE by a full,open dedicated public street.
Staff w�as concerned that neither Condition Numbers 5 nor 6 directed the applicant to install the
path in Open Space Tract C. Therefore, Condition Number 6 shall be altered to read as follows:
6. The path shall not intrude into the lot areas or privacy of the sideyards of any of
the lots so it should be routed to the north in the wetland buffer to the cul-de-sac. .
Tne applicant snall be responsible for constructing the pathway. -
The parties may seek additional clarification, seek additional reconsideration or appeal to the City
Council within ]4 days of this decision. Such additional relief shall be filed not later than 5:00
p.m. on August''?, 2001.
If this office can be of further assistance please feel free to write.
Sincerely,
��.r
�'`�'+��✓
Fred J. Kauf an
Hearing Examiner
FJK/kw
cc: Mayor Jesse Tanner
Councilperson Kathy Koelker-Wheeler
Jay Covington, Chief Administrative O�cer ,
Larry Warren,City Attorney '
Gregg Zimmerman,�'Ian/Bldg/Public Works Administrator
Neil Watts, Development Services Director
Sue Carlson, Economic Development Administrator
Alex Pieuch, Economic Development Director ',
Larry Rude, Fire Marshall
Larry Ivleckling,Buildin� Official
Plannin�Commission
Transportation Division
Utilities Division
Jennifer Henning,Development Sen•ices
Janet Conklin,Development Services
Sandi See�er,Development Services
Parties of Record
3
�� �qe38
July 16,2001
OFFICE OF THE HE ARING EX�.MINER
CITY OF RENTON
REPORT AND RECONIlVIEIV�ATION
APPLICANT: Bob Wenzel
Belmont Homes
PO Box 2401
Kirkland, ��'A 98083
File No: LUA00-029,PP,ECF
LOCATION: Union Avenue NE, between NE�`�Street and NE 7`� Street
SLTMMARY OF REQUEST: Subdivide a 7.32 acre site into 42 lots suitable for construetion
of detached, single family houses
SUNIIv1ARY OF ACTION: Development Services Recommendation: Approve �vith
conditions
DEVELOPMENT SERVICES REPORT: The Development Services Report was received by the
Examiner on June �, 2001.
PUBLIC HEARING: After review�ing the Development Services Report, examining
available information on file with the application, field
checking the property and surr�unding area; the Examiner
conducted a public hearing on the subject as follows:
�UTES
The following minutes are a summan�of the June 12, 2001 hearing.
Tl:e legal record is recorded on tape.
The hearing opened on Tuesday,June 12,2001, at 9:45 a.m. in the Council Chambers on the seventh floor of the
Renton City Hall. Parties wishing tq testify were a�rmed by the Examiner.
The following e�chibits were entered into the record: �
Exhibit No. 1: Yellow file containing the original Exhibit No. 2: Preliminary Plat Map �,
application, proof of posting,proof of publication and �'
other documentation pertinent to this request.
Exhibit No. 3: Preliminary Plat Map,North Portion Ex6ibit No. 4: Preliminary Plat Map, South Portion
Eahibit No. 5: Topography Map and Existing Site Ezhibit No. 6: Finish Grading Plan
Conditions
Exhibit No.7: General Utility Plan Exhibit No. 8: Sanitary Sewer Profiles
Exhibit No. 9: Drainage Control Plan Exhibit No. 10: Storm Drainage Profiles
��
'�+r`;��• ,i: .3 ' •'-♦
�Tf�ie Vineyards Preliminary Pla�
File No.: LUA00-029,PP,ECF
July l6, 2001
Pa?e 2
Exhibit No. 11: Tree Cutting/Land Clearing Plan Exhibit No. 12: Zoning Map
Exhibit No. 13: Wetlands Trail Background Exhibit No. 14: Wetland Delineation Map
Information
7'he hearing opened�vith a presentation of the staff report by Elizabeth Hi�Qins, Senior Planner, Development
Services, City of Renton, 10�5 S Grady Way,Renton, Washin�ton 98055. Ms. Higgins reported that the owner
of record of the tax parcels involved is Bob Wenzel. The property is located at»0 Union Avenue NE. There is
an emergency access proposed at the southern portion of the property that would front on Union Avenue NE.
The property is zoned R-10. There are some other zones around it. The property to the east is R-10 and
abutting that is a suburban zone. To the north is an R-8 zone. There is an R-8 zone on the eastside and also
some R-14 with developed apartment buildings or condos at the southeastern portion. The property all around it
i is developed except for the property abutting to the west.
The proposal is to subdivide, by means of a preliminary plat,property existing of about four tax parcels. There
are structures on the ro e in various state
p p rty s of disrepa�r. The structures will all be removed from the srte.
There are wetlands located on the property that continue on to abutting property. The southern portion of the
development has wetlands with a�0-foot buffer because they have been classified as Category 2 wetlands. The
northern part of the properry has been more impacted by past development. These wetlands have been classified
as Cateaory 3 and have a proposed'S-foot buffer. There is a small isolated�vetland in the southeast corner of
the property that because of its size is not regulated by the Cin� of Renton and «�ill be filled.
The applicant has proposed developing 42 lots suitabie for detached single-family houses. The R-10 allows
attached or semi-attached housing. The density could be 13 d�velling units per acre because the homes will all
be detached. Because of the�retlands on the property and the confi�uration of the property the proposed density
is only 7.7 d�velling units per acre.
Access to the site would come from NE 6`� Street. It�vill not continue through because there is no right-of-way
dedicated at this time and there are wetlands. The proposal is to extend NE 6`" Street onto the site and where
there would be a T-intersection. NE 6`� Street would continue to the south and then precede west through an
emer�ency access to L'nion Avenue NE. To the north would be a new public road Vashon Avenue.
The pipestem out to Union Avenue NE has been proposed as a paved pedestrian walkway. Staff vvill have to
- work with the applicant to connect tne paved walkway over to the new Vashon Avenue so that it does not just
end before reaching Vashon Avenue.
Stormwater will be collected from all the paved areas and directed to a detention facility where it wil] be treated
prior to being discharged into a City system. The roof drains will probabl� be infiltrated due to the ��etland.
1'he Environmental Review Committee (ERC)met and discussed this project and issued a Determination of
Nonsignificance with Mitiaation (DNS-M). There were no appeals filed. The ERC developed five mitigation
measures that include; using the ]998 King County Surface 1�'ater Design Manua] to calculate the surface water
runoff and that Leve12 flow control be used,the wetland buffers be delineated with a 4-foot high split rai]wo� '
fence, the applicant pay the applicable transportation mitiQation fee at the rate of$75 for each new average
weekday trip attributable to the project,the applicant pay the fire mitigation fee at the rate of$488 per ne�
single-family residential lot, and that the applicant pay the park mitigation fee a* `!� -��� �``'��" �F ^��� �
single-family lot.
..—
e —
J
The Vineyards Preliminary Plat
File No.: LUA00-0?9,PP,ECF
July 16, 2001
Page 3
The criteria used for evaluatin;the appropriateness of the preliminary plat included the land use element for
residential options. This is the Comprehensive Plan designation that allows the 10 units per acre density. This
is a di�cult zone in the City. It allows very small lots. There are some di�culties in getting this zone to work;
but staff believes that this plan is one that will probab(y work in this zone.
The intent of the R-10 zone is to create affordable housing in the City. The lots will range in size from 3,»9
square feet to 7,�39 square feet. The avera�e lot size will be 4,600 square feet. 1�1ost of the lots are directly
accessible from the new pubIic streets or the cul-de-sac. Lot 17 is located in back of lot 16 and will be
accessible from a drivewav extended from NE 6`" Street.
The applicant requested that the standard right-of-way of�0 feet be reduced down to 42 feet. Sidewalks may be
placed in easements on private property. The pavement width would still be the standard of 32 feet.
The advisory notes have been revised since they were issued with the Environmental Committee Review. These
are items that are required by code or othen�ise required by the City but are not appealable.
There are some special utility requirements covered in the advisory notes. Because staff is now looking at the
potential development of the abuttin�property there is a requirement that a sewer extension connect NE 6`�
Street with the abutting property. In the��icinity of the drainaae pond there needs to be a center sewer
connectiori up to the abuttin� propem. The se�ver connec:ion can be made either±rom Union Avenue NE or
from NE 6`� Street.
Staff�vill be requesting that a native gro��-th protection easement be created to protect the wetlands. There is
currentty a road in the 50-;oot bufier. There is some additional area that is not ciesignated as wetland or buffer
that could be used for buffer averaDin�. The buffer cannot be any less than '?� feet. ��'ith this in mind there is
still a road within 25 feet of the wetland. Trails are allowed in a buffer.
Ms. Hi�Qins would recommend an added condition that a revised wetland delineation be submitted
demonstratina the ed�e of the wetland off the property, which would require cooperation with the neighbor, and
that the 2�-foot buffer line be continued.
When this apptication was submitted the 1998 King County Surface Water Desien Manual was not required so
it is unknown at this time how big the detention system has to be. Before the developer completes the
construction documents they would be required to do calculations based on the 1998 King County Surface
Water Desi�n Manual.
Ms. Hi�bins �vent over the conditions by staff. Conditions include; compliance with the Environmental Review
Committee I�fitigation measures; a paved pedestrian walkway, preferably concrete, be constructed in the public
right-of-way (pipestem to Union Avenue�IE};and a maintenance agreement be drafted and recorded or a
homeo�vners' association be established for maintenance of the common areas. An additional recommended
condition is that a native growth protection area easement be created for the wetland and the buffer areas.
Robert Wenzel, 11411 NE 124`h St. Suite 22�,Kirkland, WA 98034 stated that he is the owner and the
applicant. The o`vner of record is Belmont Homes, Inc. He is the president of Belmont Homes. He concurs
with staff on compliance and��vill comply with the ERC miti�ation measures. He is in support of the new native
growth protection area requested today. In paying the mitigation fees he wants to clarify the number of credits
that are received for e:cisting structures or existing tax lots. There are currently six legal tax lots in the project.
Mr. Wenze]'s concerns re�ard the pedestrian pathway that staff would like dedicated for public open space. The
r,�'�V,,��.� rh�t n�-,ac n>>• tr� T�ninn .�t'P�^��?��F .�nPc c�n t}�r�„n(� t�� m1�n nnrt�np nfthe t�'?t�'?n(a rC1^.C1'"11C't1R�! r�1tc
�
The �'inevards Preliminarv Pla�
File No.: LUA00-029,PP,ECF
July l6, 2001
PaQe 4
path�va}' out of concrete or asphalt wouid be a challenge. The existing roadway goes through the wetland and is
submerged a fair part of the year. To put a functional long life concrete or asphalt walkway through there would
be very challenging. It is possible that a less invasive type of pathway, such as crushed rock or chips of some
kind,miaht present a better opportunity to connect the pathway through the wetland buffer. �I
Ms. Hie�ins stated that the City is not interested in taking this piece of property just to maintain it if there is no
walkway on it.
Chen l Girard, American Engineering Corp.,4032 148�'Avenue NE, Redmond, WA 980�2, stated that the
proposal as it currently exists regarding the eye brow or half cul-de-sac at NE 6'h Street would in fact continue
the sidewalk in a depressed form around the actual right-of-way or vehicular travel pattern on at the southern
edge of the espanded apron. T'he curb and gutter is proposed as rolled curb and cutter, which is drivable �
surface. This area is also proposed as an alternative turn-around for emergency vehicles. �
Ms. Girard reported that the turn around area at the end ofl�'E 6�' Street is an expanded pavement area that was
proposed to assist the public in turning around. .4Qain rolled curb and gutter was proposed to create a drivable
surface making the total drivable surface 30 feet wide, which is usually ample for a normal vehicle to turn
around in.
The sanitary sewer,with respect to the offsite parcels immediately north of lots 17 and 20, is currently proposed
sanitary sewer easement. There is sanitary sewer at the eastern portion of the site at NE 6`�Street but due to its
depth the majority of the site could not be served from this (ocation. They are proposin; connection for sanitary
sewer via easement at the�vesterly extension of NE 6`� Street and southerly along Union Avenue NE to an
existing structure near NE �`'' Street intersection with Union Avenue NE.
Tracts A and D on the preliminary plat are setup such as they can be dedicated native growth protection areas.
The property immediately west of Tract E future development is an open right-of-way. At this point and time
there is no proposal for utility connection through the wetland. That tract is reserved for future development
and/or buffer averaging if it is needed.
A pedestrian walkway is possible through the pipe stem out to Union Avenue NE as lon�as there are mitigating
proposals. They are currently proposing that the pedestrian access be provided from Union A��enue NE in an
easterly direction to the back of lot 3�then northerly along the buffer to where the path would connect with the
side«•alks at the extension of Vashon Avenue NE.
Tract B is identified as the storm drainage tract. The storm drainage calculations have been prepared and there
is approximately 17,000 cubic feet of combined detention and water quality storaae that fit into that facility with
an approsimate active storage depth of five feet. They can always go deeper; there is an additional two feet of
e:ctra storage capacity avaiIable. The storm drainage issues have been addressed.
Ruth Brandal, PO Box 12820, Everett, WA 98206, stated that she and her husband are the owners of the
property located north of I�'E 6'h Street and south of the pipestem that fronts on Union Avenue NE. They have
done a wetland study. The wetland to the north near the cul-de-sac and the wetland down in the south is all one
continuous wetland that runs through the center of their properry. Because of the size of the wetland there really
is nothing much to be developed on the eastern boundary of their property. All of the development would be
proposed to front on Union Avenue NE and it would probably be something like a nine lot short plat. Because
of that they need to know that they have access to sewer.
Kayren Kittrick, Development Services Division, stated that currently there are no standards for the proposed
turnaround at the western edge ofNE 6'h Street. There are emergency turnarounds, fire department turnarounds
�1
The Vineyards Preliminary Plat
File No.: LUA00-029,PP,ECF
July 16, 2001 I
Page � �
but for a turn around in a street that has an access out, there is no such standard. It was known that the wetland
would encroach so this was worked out so that they could show that there was something for the public to use to
turnaround. The standard for the pavement on the access easement or emergency access is 20 feet of pavement. I
Bollards are not allowed in any shape or form and the fire department will disallow the entire project if the ',
developer tries to put a bollard in. A gate is allowed and will be recommended. Sewer will be going across ,
where the emergency access is located. I
The�vastewater utility had declared that they needed an opening, an easement for possible service. "I'he pre- ;
application at that time showed the possibility of there being a lot above lot l 7. They were requirinQ an
easement but not necessarily an extension. It�i�as matter of making service available to public service. There
was concern because of the size of the parcel to the north, the Brandal parcel,that there be access to that edge
because the sewer can be extended up Union Avenue NE to serve the properties that face Union Avenue NE. �
Rolled curb and gutter are not allowed in this area. The depressed sidewalk in the proposed eyebrow area is also
not allowed in current standards. It was unclear if this area�vas going to be dedicated or not and if it is not, staff ,
wants nothing to do with it. Shared driveway access for these lots is highly recommended but not required. ,
Based on the calculations that Ms. Girard shared for storm drainage it will probably be able to handle it and
there is a certain amount of water that is wanted to go into the��vetlands anytivay to keep them watered. Both of
the«-etlands to the north and the south were under code enforcement actions for several years running due to the
damase bein' created b}� local owners doing some minor fill here and there. Over several years more dirt and
garbaae was brought in. Therefore it is very likely in looking at them that the wetland biologist could very well
make a determination that they were different types or grades of wetland. There has been varying degrees of
success in getting the code enforcement against it. Just above the north property line where it connects into The
Orchards, �'Vetland A star[ed out as a garba�e line ditch and ���as created as part of the miti�ation for The
Orchards plat�vhen it w•ent in.
Mr. ��'enzel stated that in re�ard to the wetland in tract D, there was an ageement of some kind that was crafted
between the City and the previous owner that either miti�ated or made an agreement that that wetland buffer
would be 2� feet in consideration for some mitigation a�eements. This is how he established the 2� feet on
tract D.
Mr. «"enzel stated that he has no problem with eliminatin�the eyebrow.
,
Ms. Hiosins stated that she had a few suggestions. A fourth condition was added that the native growth
protection area easement be established. Condition number nvo can be revised by deleting concrete paved to
say,"a pedestrian walk.vay shall be constructed." This will ]eave the negotiation with the applicant as to the
most appropriate type of construction for this walkway. There does need to be some type of pedestrian
connection in order for students to get out to Union Avenue NE to catch a bus to go to school. There are many
wooden structures built in wetlands that cause very little impact. A suggested additiona] condition would be that
a wetland mitigation plan be submitted prior to the recording of the plat. In this plan measures that need to be
taken to restore�vetland areas if necessary can be looked at. There is some intrusion of roads into the wetland
area. Some averagina or mitigation could be used in those areas along the edges where there is no development
planned and are outside of proposed lots. This should be submitted in a mitigation plan.
Mr. w'enzel stated that the end of NE 6`" Street will be revegetated and a miti�ation plan will be submitted.
Mr. 13�'enzel stated that he did provide a wetland study, delineation and the boundaries in the plan. He does not
believe that they have made a particular restoration plan. What they have been working on is making sure that
there�vere no other materials or issues in the wetland other than taking out the fill and restoring it.
� �
The�'ineyards Preliminary Pla�
File No.: LUA00-029,PP,ECF
July l 6, 2001
Pa?e 6
Ms.Brandal would like more clarification on the outcome of the sewer issue. She was under the impression ''
from her conversation with the utility that the sewer needed to be at a maximum two percent slope from NE 5`h
Street and Union Avenue NE in order to go beyond her property to the north and service some properties that �
come up toward Union Avenue NE.
Ms.Hi�gins clarified that the statement"side sewer lines must have a two percent slope" is a standard '
statement. It is not specific to this particular property. Everytime a developer puts in a side sewer it has to be j
sloped two percent. It is an issue that will be looked at in the construction document phase.
Ms.Brandal stated a concern regarding a sewer extension. The property north of the emergency access road and I
west of the proposed of development�and south of her property has a g�-eat deal of wetlands and probably has ',
minimal development potential. The problem exists that without getting some required sewer line to the north
somewhere between Union Avenue NE and tract B heading north to the boundary line she may not have the
right or access to get sewers to her property except by coming up the middle of Union Avenue NE.
Ms. Hi�eins explained that the way it reads is, an eYtension to the property boundary east of Union Avenue NE
and north Tract B. She believes the City does require that utilities be stubbed to undeveloped parcels. Streets
are not required to be stubbed.
Ms. Kittrick stated that the discussion from the wastewater utility is that they do want a connection to the north. �
If the connection cannot be decided upon as to exactly the depth,etc. they at the least want an easement so that
they can have a connection. The concern is about the wetlands. Ms. Brandal would like the sewer connection to
be along the western boundary,with the delineation of the wetlands it wouid encroach. By being on the other
side it is out of the�vetland boundary. It�vould have to be along Union A�•enue NE to be the most effective and
shortest range. They will work with all people involved to find an equitable manner of serving while still
presen�ing and conserving the wetlands and do the least amount of damage.
The Esaminer called for further testimony reearding this project. There was no one else wishing to speak, and
no further comments from staff. The hearing was adjourned at 11:20 a.m.,to be continued to a future date.
The continued appeal hearing opened on Tuesday, July 3, 2001 at 9:32 a.m. in the Council Chambers on the
seventh floor of the Renton City Hall.
� Ms. HiQains stated that there were questions on several issues. One of those issues was alternative methods for
providing a pathway throu;h the wetland. There is a 16-foot access that crosses at the north of the Brandal
property, which is a large parcei that may be developed in the near future. It connects the proposed plat with
Union Avenue NE. It goes through a wetland. One of the recommended conditions of approval by staff was to
provide a pedestrian pathway in this area so that students trying to get out to Union Avenue NE can get there
without having to trespass or mush throu?h the wetland. The Environmental Review Committee supported this
concept and the head of pub(ic works has committed the City to maintaining it if it is built by the developer.
Staff has requested a paved pathway and the developer is proposing an alternative to pavement such as gravel or
crushed rock.
Ms.HiQoins stated that additional information was required from the applicant that would clarify the location of
the wetland on the adjacent property.
The ��'etland Delineation map was entered as Exhibit No. 14. �
Zq
_
The Vineyards Preliminary Plat
File No.: LUA00-029,PP,ECF ;
July l6,?001 ��
Page 7 '
Ms. HiaQins demonstrated on the map where the buffers are located. The buffer does not connect very easily
where the pipestem goes out to Union Avenue NE. One of the problems with this wetland is that the upper area
is very disturbed. This wetland to the south is slightly better quality. It has been impacted by fill that took place
over the years. It is a Category 2 wetland and is a Category 2 across the Brandal property. There will have to be
a connection somehow to public road. T�he developer will have to make suggestions on how to move the
property lines around to connect this pathway to the public road. A pathway can be placed in a wetland buffer.
There was some question as to whether or not a road would be allowed within 2� feet of the wetland. This
concerns the emergency access running directly alon� lots 13, 14 and 15. It is the extension ofNE 6`" Street. It
will be a paved 20-foot��ide road. They could do some buffer averaging and reduce the buffer down in this area
but the buffer cannot be reduced more than �0 percent of the required width. This road is within the 25-foot
area. Staff reviewed the Code and found in Renton Municipal Code; Section 4-3-OSOC, Subsection 5: Specific
Exemptions Critical Areas and Buffers,E. Roads Parks and Public Utilities,4.Modification of Existing Utilities
and Streets by 10 percent or less:
"Over building enlaraement beyond existing project needs or replacement of existing utilities
systems and replacement and or rehabilitation of existing streets provided that the work does not
increase the footprint of the structure line or street by more then 10 percent within the critical area
and or buffer areas is exempt from the critical area regulations."
This is an existing street, it cuts across the Williams propem�but it has been serving the existing houses at the
eastem portion of this proposed project. The street has been established. Staff is not proposing that it be built to
public street standards. They are requiring that it be paved for emergency access but are not requesting that it be
increased in the buffer area by more then 10 percent so it w�ouid be an exempt activity.
Ms. HieQins stated that the configuration of the emergenc�� street is not a City of Renton standard street
configuration. It is a Cin�of Seattle type situation and it has been accepted.
Ms. Girard discussed the alternative surfacin� for the proposed walkway other than a concrete walkway. She
has been told that the inundation depth is between three and four inches of water. It could probably get up to a
half a foot in depth. The�� are not averse to installing a boardwalk; however, the maintenance, installation costs
the disturbance to the wetland would be greater than installing a crushed walk surface or perhaps even a wood
chip surface to a sufficient depth.
As far as the route of the pathway it was suggested that the pathway could connect to the public road through
lots 37 and 38. Currentl��these lots are configured such as thev are of a minimum width. Putting a pathway
between these ri�vo lots could interrupt the building potentia] of those lots. They are currently proposing running
the pathway along the ed�e of the buffer in a northerly direction up to where it connects directly to the cul-de-
sac.
The applicant has decided to eliminate the eyebrow at the southeast corner or the intersection of NE 6'" Street
and Vashon Avenue. They would still like to install the other eyebrow,which is at the westerly terminus of NE
6�' Street. This is not for emergency vehicles; it would be for the public.
Ms. Kittrick stated that the eyebrow�at the end of NE 6`� Street is a design that transportation and traffic people
were familiar with from their history in Seattle. It is specifically for the convenience of those who are unaware
that it is a dead end. It�.�ould need to be marked no parking. City of Renton will have the ability to have
parking enforcement because it is a public street. It would be dedicated public right-of-way. It won't be an easy
turn it�vill be a broken li-turn.
��
�
The Vineyards Preliminary Plat '
Fite No.: LUA00-029,PP,ECF
July 16,2001
Page 8
Ms. Hieeins stated that she had suggested that the pathway be connected to Vashon Avenue between lots 37 and
38. The reasoning for this is on the wetland map the lot lines have changed somewhat. Lot 34 has a wider
frontage on the cul-de-sac then required. The developer could shift all the east-west property lines for lots 3�1,
35, 36 and 37 to the north leaving an area between lots 37 and 38 to connect to Vashon Avenue.
The Examiner called for further testimony regarding this project. There was no one else wishing to speak,and
no further comments from staff. The hearing ciosed at 9:�8 a.m.
FINDINGS,CONCLUSIONS & RECOMMENDATION
Having reviewed the record in this matter,the Examiner now makes and enters the following: -
FINDINGS:
1. The applicant, Belmont Homes,Inc.,filed a request for approval of a 42-lot preiiminary plat. �
2. The yellow file containing the staff report,the State Environmental Policy Act(SEPA}documentation and
other pertinent materials was entered into the record as EYhibit#1.
3. The Environmental Review Cammittee(ERC) issued a Determination of Non-Significance-Mitigated
(DNS-M)-
4. The subject proposal was reviewed by all departments�vith an interest in the matter.
5. The subject site is located at >j0 Union Avenue NE. The subject site is located on the east side of Union
north of NE Sth Street. The subject site is actually approximately 120 feet east of Union. It has a Union
Avenue address due to a narrow 16-foot wide, appro�imately 3�0 foot long dogleg out to Union.
6. The subject site was annexed to the City in June 1981,�vith the adoption of Ordinance 3553.
7. The site received its current zoning classification, R-10 (Residential- 10 dwellin?units per acre), with the
adoption of the new zonino code in June 1993. The density in the R-]0 zone is required to be between 7
and 10 dwelling units per acre.'
8. The map element of the Comprehensive Plan designates the area in which the subject site is located as
suitable for the development of residential options, but does not mandate such development without '
consideration of other policies of the Plan.
�
9. The subject site is an irregular somewhat L-shaped parcel. The subject site is narrow in the north and
widens to the south. Its eastern and southern property ]ines are straight�vhile its western property line jogs
considerably around adjacent property to the west.
10. The subject site is approximately 318,728 square feet or 7.32 acres. The parcel is approximately 955.84
feet long(north to south). The parcel is approximatel}�495.78 feet wide at it south boundary and 32l.02
feet wide at the north end.
1 I. The sub�ect site consists of a number of undertying lots. A number of older single-family homes and
outbuildings are located on these underlying lots. These buildings will be removed if the new plat is
approved.
�
1
The Vinevards Preliminarv Plat
File No.: LUA00-029.PP,ECF
July 16, 2001
Page 9
12. The western edges of the subject site are dominated b}'wetland areas. Near the northwestern corner of the
subject site are Class 3 wetlands. It is approximately I7,000 square feet in area. Class 3 wetlands require a
25-foot buffer. Near the southwestern corner of the subject site is an approximately 3,920 square foot
Class 2 wetland. A 50-foot buffer is required for Class 2 wetlands. These«�etland areas actually continue
off site to the west and are somewhat interconnected. The narrow do�leg in the center of the subject site
that connects to Union Avenue i�TE also traverses across a wetland. The total wetland acreage is
approximately 21,53� square feet.
13. There are a variety of residential uses in the vicinity of the subject site with a mix of R-10 zoning such as
found on the subject site and R-8 (Single Family; Lot size-4,500 sq ft). Along NE 4th Street south of the
subject site are commercial uses in a Center Suburban Zone(CS).
14. The subject site generally slopes down to the southwest and northwest where the primary wetlands are
located from a hi�h point near the center of the east property line. The slope approaches approximately 12
percent(12%)and is unregulated. ,
15. The R-]0 zone allows both single family and attached housing. The appIicant proposes developing 42 lots
for detached single-family homes only.
16. ApproYimately 58,492.00 square feet would be used for roads. This, along�;�ith the wetland area, is
subtracted from the aross acreaje to determine densin�. The approximately?38,701 square feet remaining
would have a density of 7.7 units per acre.
17. The main access to the subject site���i11 be from an "L-ali�ed" road��•a}'��'ith a T-intersection to Bremerton
Avenue NE. The 42 lots would be located on both sides of this road.
18. The R-]0 zone requires a minimum lot size of 3,000 square feet and lot widths of 30 feet for interior lots
and 40 feet for corner lots as�vell as a lot depth of 5� feet. Staff noted that all the lots meet these minimum
requirements.
19. The applicant will be importing approximately 1?,000 cubic ��ards of clean ;il] to create road sub�rades and
suitable building pads for homes.
20. NE 6th Street, a new east to west Street,would enter the plat from the east from Bremerton Avenue NE. It
would almost immediately form a T-intersection. At that point it would join a new segment of Vashon
Avenue NE. Vashon Avenue NE would end in a cul-de-sac at its north and curve to rejoin NE 6th Street as
it runs west toward but does not connect to Union. There would be a gated, emergency connection to
Union Avenue NE. Proposed Lot 17 would have its access via an easement across proposed lot 16.
21. The applicant originally included a widened bulb on the outside of where Vashon and NE 6th Street joined
and turned. At staffs suggestion that was removed during the public hearing. There is also a slightly
widened area at the western end of 6th where it ends at the emergency gate. It is somewhat like a pull out
but not as wide as a parking space. It is intended to allow vehicles to complete a U-turn.
22. The wetlands and their buffers appear to be fully delineated on updated plans submitted at the continued
hearing. The portion of NE 6th Street at the southwestern corner of the plat will cross or displace
approximaj�ly 2,039 square feet of wetland buffer area.
23. T7ie 42 homes would �enerate approximately 402 traffic trips per day over neighborhood roads. There
32
The�'ineyards Preliminary Plat
File No.: LUA00-029.PP,ECF
July 16,2001
Page 10
were no reports of transportation issues by Staf£ ,
24. The subject site wilI generate approximately 19 students. The students would attend schools in the Renton �
School District and would be placed on a space available basis.
25. The subject site is ]ocated within an Aquifer Protection Area and appropriate protective language will be
required on the plat documents. Clean, certified fill w�ill be required for any materials imported to the site.
26. Tract B, in the south�vest corner of the subject site, immediately east of the southwestern wetland,�vould
serve as the storm water detention system. VVater quality treatment will be provided on the site. The
applicant will be required to comply with the 1998 King County Surface Water Design Manual.
27. The subject site will be served by City of Reriton sanitary sewer and water service.
28. Staff has recommended that a trail or pathway be provided between the cul-de-sac and Union Avenue NE
across the narrow dogleg that connects between the north interior of the parcel and Union Avenue NE. It
would cross the wetlands to provide a footpath since the route down to NE 6th Street and Union Avenue
NE from the cul-de-sac is fairly lengthy. An issue was the type of surface material to be used since the
dosleg is inundated by wetland water during certain times of the year. Suggested surfaces were a hacd
surface such as asphalt or concrete, b avel, bark or a boardwalk. The connection to the cul-de-sac was also
at issue. The question was should the path run from the wetland buffer at the cul-de-sac which would run
to the rear of approximately four lots and traverse north or traverse directly east from the dogleg between
Proposed Lots 36 and 37 or between 37 and 38. If it ran between the lots, it might reduce one of the lots in
size and be intrusive.
CONCLti SIONS:
1. The proposed plat appears to satisfy the pubiic use and interest. The plat will provide 42 additiona] smaller
lots for detached housing. The plat has been desijr►ed to work with and around two wetlands and their
respective buffers while providing a fairly rectangular lot layout and rectilinear street system.
2. The plat creates additional housing while preserving the natural wetland communities on the site thereby
meeting the policies and goals of the Comprehensive Plan.
3. The project provides infill in an area in which urban services are available. It meets the required densities
of the City with a density of 7.7 dwelling units per acre.
4. The development should not tax either the road system or the existing utility infrastructure. It will,
however, add another approximately 400 cars to local streets.
5. The development of the additional lots will increase the tax base of the City. The applicant will also be
paying Fire,Parks and Transportation Mitigation fees to heip offset its impacts on City services.
6. Staff is correct that a pathway between the northern portion of the plat and Union Avenue NE across the
dogleg makes sense as a walking shortcut. It should be designed so that it is useable most, if not all,
seasons ofthe year. It probably will be most in demand during the school year, which also probably
corresponds with the more rainy or wet periods. The choice of design and material should be determined
by the Parks Division of the City and they may select from raised,planked boardwalk,asphalt;concrete or
other suitable, low maintenance materials which further permit the wetland functions to be minimally
disturbed and allow water to flow appropriately bet�veen the wetland areas north and south of the pathway.
33
.�-
The Vineyards Preliminary Plat
File No.: LUA00-029,PP,ECF
July 16, 2001
Paae 11
7. The path should not intrude into the lot areas or privacy of the sideyards of any of the lots so it should be
routed to the north in the wetland buffer to the cul-de-sac.
8. The non-standard turnaround at the western end of?�E 6th Street does not seem appropriate. Creating a
situation where vehicles will probably have to use private driveways to negotiate a legal U-turn does not
appear reasonable and it not justified by code. It should be a standard cul-de-sac turnaround although
offset to the south to avoid any further intrusion into the wetland or its buffer. This probabiy will require a
reconfigurin;of the lots in that area and a possible loss of one lot.
9. The applicant shall provide a means of both wetland and aquifer recharge.
10. The development of the subject site will create additional traffic and noise associated with residential I
development but these impacts should not create any undue impacts on the overall community.
1 I. In conclusion,the proposed plat appears to provide a new and reasonable residential community and should
be approved by the City Council. ' �
RECOi�•IMENDATION:
The City Council should approve the Preliminary Plat subject to the following conditions: II
l. Compliance with ERC Miti�ation Measures: The app(icant is required to comply with the Mitigation
Measures which«�ere required by the Environmental Review Committee Threshold Determination.
2. A maintenance asreement shall be drafted and recorded, or a Homeowners' Association be established, for
the maintenance of all common stormwater and access improvements.
3. The applicant shall, at the western end of NE 6th Street, design a standard cul-de-sac turnaround, offset to
the south to avoid intrusion into the wetland or its buffer. If this requires reconfiguring of the lots, the plat
plan shall be submitted for review by staff and the Examiner prior to submission of the plat to the City
Council.
4. The applicant shall provide a means of both wetland and aquifer recharge.
�. The pathw�ay shall be subject to review and approval by the City. The choice of design and material should
be determined by the Parks Division of the City and they may select from raised planked boardwalk,
asphalt, concrete or other suitable low maintenance materials,which further permit the wetland functions to
be minimally disturbed and allo�v water to flow appropriately between the wetland areas north and south of
the pathway.
6. The path should not intrude into the ]ot areas or privacy of the sideyards of any of the lots so it should be
routed to the north in the wetland buffer to the cul-de-sac.
"T!
The Vineyards Preliminary Plat
File No.: LUA�O-029,PP,ECF
July 16, �001
Page 1?
ORDERED THIS 16`� day of 3uly, 2001. il
_�� '�,
� �
FRED J. KAUF N
HEARING EXA ER
TR.4NSNIITTED THIS 16`� day of July,2001 to the parties of record:
Elizabeth Hig�ins Robert Wenzel Ruth Brandal
1055 S Grady Way 11411 NE 124`�' Street, Suite 225 PO Box 12820
Renton,WA 980» Kirkland, V�%A 98034 Everett, WA 98026
Kayren Kimick Cheryl Girard .
105� S Grady Way American Engineering
Renton, u'A 98055 4032 148`� Avenue NE
Redmond, WA 9805?
TR�NS�SITTED THIS 16'� day of July, 2001 to the follow�ing:
Mayor Jesse Ta�er Greg�Zimmerman, Plan/Bldg/PW Admin.
Members,Renton Planning Commission Neil Watts,Development Services Director
Lam•Rude, Fire Marshal Sue Carlson,Econ. Dev. Administrator
Lawrence J. Warren, City Attorney Larry Meckling,Building O�cial
Transportation Systems Division Jay Covington, Chief Administrative Officer
Utilities System Division Councilperson Kathy Keolker-Wheeler
South County Journal
Pursuant to Title IV, Chapter 8, Section 100Gof the City's Code, request for reconsideration must be filed in
writin�on or before 5:00 p.m.,July 30,2001. Any aggrieved person feeling that the decision of the Examiner
is ambi�uous or based on erroneous'procedure, errors of law or fact, error in judgment, or the discovery of new
evidence �vhich could not be reasonably available at the prior hearing may make a written request for a review
by the Esaminer within fourteen (14) days from the date of the Examiner's decision. This request shall set forth
the specific ambiguities or errors discovered by such appellant, and the Examiner may, after review of the
record,take further action as he deems proper.
An appeal to the City Council is governed by Title IV,Chapter 8, Section 11 U,which requires that such appeal
be filed with the City Clerk, accompanyin�a filing fee of$75.00 and meeting other specified requirements.
Copies of this ordinance are available for inspection or purchase in the Finance Department, first floor of City
HaII. An appeal must be filed in writina on or before 5:00 p.m.,July 30,2001.
If the Examiner's Recommendation or Decision contains the requirement for Restrictive Covenants,the
executed Covenants will be required prior to approval by Citv Council or final processin�of the file. You
may contact this office for information on formatting covenants.
w
'The Appearance of Faimess Doctrine provides that no ex parte(private one-on-one)communications may occur
concernin�pending land use decisions. This means that parties to a land use decision may not communicate in
3�
The Vineyards Preliminary Plat
File No.: LUA00-029,PP,ECF
July 16, 2001
Page 13 i
private with any decision-maker concerning the pr�posal. Decision-makers in the land use process include both I��
the Hearing Examiner and members of the City Council. ,
All communications concerning the proposal must be made in public. This public communication permits all '
interested parties to know the contents of the communication and would allow them to openly rebut the
evidence. Any violation of this doctrine would result in the invalidation of the request by the Court.
The Doctrine applies not only to the initial public hearing but to all Requests for Reconsideration as well as
Appeals to the City Council.
:
3�
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Stormwater Technicallnjormation Repon,Revision#1 AECJob#9838
The Vineyards October S, 2001
Section X: Maintenance and Operations Manual
The proposed storm drainage collection, conveyance, detention and water quality treatment system will
be constructed to City of Renton standards by the developer and then be turned over to the City of
Renton for ownership, operation and maintenance. The specific maintenance requirements for each of
the drainage facilities are listed on the follow�ing pages.
Access Roads/Easement
Maintenance Defect Conditions R'hen Maintenance is Results Expected When
Component Needed Maintenance is Performed
General Trash and Debris Trash and debris exceeds 1 cubic foot per Trash and debris cleared from
1,000 square feet,i.e.,trash and debris site.
would fill up one standard size garbage
can.
Blocked Roadway Debris,which could d�nage vehicle rires Roadway free of debris,which
(glass or metal). could damage tires.
Any obstructions,which reduce clearance Roadway overhead clear to 7
above road surface to less than 7 feet. feet high.
Any obshuctions restricring the access to Obstruction removed to allow at
a 10-to 12-foot width for a distance of least a 12-foot access.
more than 12 feet or an}�point restricting
access to less than a 10-foot width.
Road Surface Settlement, When any surface defect exceeds 6 inches Road surface uniformly smooth
Potholes,Mush in depth and 6 square feet in area. In wzth no evidence of settlement,
Spots,Ruts general,any surface defect,which hinders potholes,mush spots,or ruts.
or prevents maintenance access.
Vegetation in Weeds growing in the road surfaces that Road surface free of weeds taller
Road Surface are more than 6 inches tall and less than 6 than 2 inches.
inches apart w�thin a 400-square foot
area.
Shoulders and Erosion Damage Erosion�+�ithin 1 foot of the roadway Shoulder free of erosion and
Ditches more than 8 inches w�de and 6 inches matching the surrounding road.
deep.
Weeds and Brush Weeds and brush exceed 18 inches in Weeds and brush cut to 2 inches
height or hinder maintenance access. in height or cleared in such a
way as to allow maintenance
, access.
37
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Scormwater Technicallnformation Report,Revision#! AECJob#9838
The Vineyards October 5,2001
Closed Detention Systems(Pipes/TanksNaults)
Maintenance Defect Conditions When Results Expected When
Component Maintenance is Needed Maintenance is Performed
Storage Area Plugged Air Vents One-half of the cross section of Vents free of debris and sediment.
a vent is blocked at any point
with debris and sediment.
Debris and Sediment Accumulated sediment depth All sediment and debris removed
exceeds 10%of the diameter of from storage area.
tt►e storage area for%Z length of
storage vault or any point depth
exceeds 15%of diameter.
Eacample: 72-inch storage tank
would require cleaning when
sediment reaches depth of 7
inches for more than %z length
of tank.
Joints Between Any crack allo�y�ing material to All joints between tank/pipe secrions
Tank/Pipe Section be�ansported into facility. are sealed.
Tank/Pipe Bent Out of Any part of tank�pipe is bent Tank/pipe repaired or replaced to
Shape out of shape more than 10%of design.
its design shape.
Manhole Cover not in Place Cover is missing or only Manhole is closed.
partially in place. Any open
manhole requues maintenance.
Locking Mechanism Mechanism cannot be opened Mechanism opens with proper toois.
Not Working by one maintenance person
with proper tools. Bolts into
frame have less than %2 inch of
thread(may not apply to self-
locking lids).
Cover Difficult to One maintenance person cannot Cover can be removed and reinstalled
Remove remove lid after applying 80 lbs by one maintenance person.
of lift. Intent is to keep cover
from sealing off access to
maintenance.
Ladder Rungs Unsafe I�ing County Safery Office Ladder meets design standards and
ancL'or maintenance person allows maintenance persons safe
judges that ladder is unsafe due access.
to missing rungs,misalignment,
rust,or cracks.
Catch Basins See"Catch Basins"Standard See"Catch Basins"Standard No. 5
No. 5
�g
Stormwaler Technical Inforniatron Report,Revision#1 AECJob#9838
The i'inevards October 5,1001 �
Control Structure/Flow Restrictor
blaintenance Defect Conditions VVhen Results Eapected VVhen Maintenance
Component Maintenance is�eeded is Performed
General Trash and Debris Distance between debris All trash and debris removed.
(Includes Sediment) build-up and bottom of
orifice plate is less than 1-'/a
feet.
Structural Damage Structure is not securely Structure securely attached to wall and
attached to manhole wall and outlet pipe.
outlet pipe structure should
support at least 1,000 pounds
of up or down pressure.
Structure is not in upright Structure in correct posirion.
posirion(allow up to 10%
from plumb).
Connecrions to outlet pipe are Connecrions to outlet pipe are
not watertight and snow signs watertight;structure repaired or
of rust. replaced and works as designed.
Any holes—other than Structure has no holes other than
designed holes—in the designed holes.
structure.
Cleanout Gate Damaged or Missing Cleanout gate is not Gate is watertight and works as •
watertieht or is missing. designed.
Gate cannot be moved up and Gate moves up and down easily and is
down by one maintenance watertight.
person.
Chain leading to gate is Chain is in place and works as designed.
missing or damaged.
Gate is rusted over�0%of its Gate is repaired or replaced to meet
surface area. design standards.
Orifice Plate Damaged or'vlissing Control device is not working Plate is in place and works as designed.
properly due to missing, out
of place, or bent orifice plate.
Obstructions Any trash, debris,sediment, Plate is free of all obstrucrions and
or vegetation blocking the works as designed.
plate.
Overflow Pipe Obstructions Any�ash ar debris blocking Pipe is free of all obstructions and
(or having the potenrial of works as designed.
blocking)the overflow pipe.
'�4anhole See"Closed Detenrion See"Closed Detenrion Systems"
Systems"Standard\o.3. Standard No.3.
Catch Basin See"Catch Basins"Standard See"Catch Basins"Standard No. 5
No. 5
39
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Stormwater Technical lnformation Report,Revision#1 AECJob#9838
The Vineyards October S,2001
Debris Barriers(e.g.Trash Racks)
Maintenance Defect Conditions When Maintenance is Results Ezpected When
Component Needed Maintenance is Performed
General Trash and Debris Trash or debris that is plugging more Barrier cleaz to receive capacity
than 20%of the openings in the flow.
barrier.
Metal Damaged/Missing Bars aze bent out of shape more than 3 Bars in place with no bends
Bars inches. more than 3/4 inch.
Bars aze missing or entire bazrier is Bars in place according to
missing. design.
Bars are loose and rust is causing 50% Repair or replace barrier to
deteriorarion to any part of barrier. design standards.
_
40
; (
Stormwater Technical Jnformation Report,Revision#! AECJob#9838
The Vineyards October S, 2001
Energy Dissipaters
Maintenance Defect Conditions When Results Ezpected When
Component Maintenance is heeded Maintenance is Performed
Extemal:
Rock Pad Missing or Moved Only one layer of rock exists Replace rocks to design standard.
Rock above native soil in area five
square feet or larger,or any
exposure of narive soil.
Dispersion Trench Pipe Plugged with Accumulated sediment that Pipe cleaned/flushed so that it
Sediment exceeds 20%of the design matches design.
depth.
Not Discharging Visual evidence of water Trench must be redesigned or rebuilt
Water Properly discharging at concenh-ated to standard.
points along trench(normal
condition is a"sheet flow"of
water along trench). Intent is
� to prevent erosion damage.
Perforations Plugged Over'/z of perforarion in pipe Clean or replace perforated pipe.
are plugged with debris and
sediment.
Water Flow�s Out Maintenance person observes Facility must be rebuilt or redesigned
Top of"Distributor" water flowing out during any to standards.
Catch Basin storm less than the design
storm or it is causing or
appears likely to cause
damage.
Receiving Area Water in receiving area is No danger of landslides.
Over-Saturated causing or has potential of
causing landslide problems.
Internal:
Manhole/Chamber Wom or Damaged Structure dissipating flow Replace structure to design standards.
Posts,Baffles, Sides detenorates to �or original ,
of Chamber size or any concentrated worn
spot exceeding one square
foot,which would make
sti-ucture unsound.
Other Defects See"Catch Basins"Standard See"Catch Basins"Standard No. 5 �
No. 5 '
Gates '
Maintenance Defect Conditions When l��iaintenance is Results Ezpected When
Component Needed Maintenance is Performed
General Damaged or Missing gate or locl:ing devices. Gates and locking devices in
Missing Members place.
Broken or missing hinges such that gate Hinges intact and lubed.
cannot be easily opened and closed by a Gate is working freely.
maintenance person.
Gate is out of plumb more than 6 inches Gate is aligned and vertical.
and more than 1 foot out of design
alignment.
Missing stretcher bar,stretcher bands, and Stretcher bar,bands,and ries
ties. in place.
Openings in See"Fencing"Standard See"Fencing"Standard
Fabric
q'�
Stormwater Technicallnforntation Report,Reti�rsion#1 AECJob#9838
The i�ineyards October 5, 2001
Catch Basins
Maintenance Defect Conditions VVhen Results Expected When Maintenance
Component Mai�tenance is�eeded is Performed
General Trash and Debris Trash or debris of more than No trash or debris located immediately
(Includes Sediment) '/�cubic foot which is located in front of catch basin opening.
immediately in from of the
catch basin opening or is
blocking capacity of basin by
more than 10%.
Trash or debris(in the basin) No trash or debris in the catch basin.
that exceeds 1/3 the depth
from the bottom of basin to
invert of the lowest pipe into
or out of the basin.
Trash or debris in any inlet or Inlet and outlet pipes free of trash or
• outlet pipe blocking more debris.
° than 1;3 of its height.
Dead animals or vegetation No dead animals or vegetation present
that could generate odors that within the catch basin.
would cause complaints or
' dangerous gases(e.g.
methane)
Deposits of garbage No condirion present,which would
exceeding 1 cubic foot in attract or support the breeding of insects
volume. or rodents.
Structural Damage to Comer of frame extends more Frame is even with curb.
Frame and/or Top than'/4 inch past curb face
Slab into the street(if applicable)
Top slab has holes larger than Top slab is free of holes and cracks.
2 square inches or cracks
wider than '/<inch(intent is to
make sure all material is
running into the basin).
Frame not sitting flush on top Frame is sitting flush on top slab.
slab,i.e. separation of more
than'/<inch of the frame from
the top slab.
Cracks in Basin Cracks wider than'/Z inch and Basin replaced or repaired to design
Wa1lsBottom longer than 3 feet,any standards.
evidence of soil particles
entering catch basin through
cracks,or maintenance
person judges that structure is
unsound.
Cracks wider than '/z inch and No cracks more than '/4 inch wzde at the
longer than 1 foot at the joint joint of inlevoutlet pipe.
of any inledoutlet pipe or any
evidence of soil particles
entering catch basin through
cracks.
Settlement/ Basin has settled more than 1 Basin replaced or repaired to design
Misalignment inch or has rotated more than standards.
2 inches out of alignment.
Fire Hazard Presence of chemicals such as No flammable chemicals present.
natural gas,oil,and gasoline.
Vegetarion Vegetation growing across No vegetation blockin,T openin� to
and blockine more than 10% basin.
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Stormwater Technical Information Report,Revision#1 AECJob#9838
The Vineyards October S,2001
Maintenance Defect Conditions When Results Expected When Maintenance
Component Maintenance is Needed is Performed
of the basin opening.
Vegetation growing in No vegetation or root growth present.
inledoutlet pipe joints that is
more than six inches tall and
less than six inches apart.
Pollution Non-flammable chemicals of No pollurion present other than surface
more than'/�cubic foot per film.
three feet of basin length.
Catch Basin Cover Not In Place Cover is missing or only Catch basin cover is closed.
Cover partially in place. Any open
catch basin requires
maintenance.
Locking Mechanism Mechanism cannot be opened Mechanism opens with proper tools.
Not Working by one maintenance person
with proper tools. Bolts into _
frame have less than'h inch
of thread.
Cover Difficult to One maintenance person Cover can be removed by one
Remove cannot remove lid after maintenance person. •
applying 801bs. of lift; intent
is keep cover from sealing off
access to maintenance.
Ladder Ladder Rungs Unsafe Ladder is unsafe due to Ladder meets design standards and
missing rungs,misalignment, allows maintenance person safe access.
rust, cracks,or sharp edges.
Metal Grates Grate w�th opening wider than Grate openings meet design standards.
(if applicable) 7/8 inch.
Trash and Debris Trash and debris that is Grate free of trash and debris.
blocking more than 20%of
grate surface.
Damaged or Missino Grate missing or broken Grate is in place and meets design
� � member(s)of the grate. standards.
i '
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: I!
�
Srormwater Technical Information Report,Revision#1 AECJob#9838
The Yineyards October S,2001 '
Conveyance Systems (Pipes&Ditches)
Maintenance Defect Conditions R'hen Maintenance is Results Ezpected«'hen
Component Needed Maintenance is Performed
Pipes Sediment and Accumulated sedunent that exceeds 20% Pipe cleaned of all sediment
Debris of the diameter of the pipe. and debris.
Vegetation Vegetarion that reduces free movement of All vegetarion removed so
water through pipes. water flows freely through
pipes.
Damaged Protective coating is damaged;rust is Pipe repaired or replaced.
causing more than 50%deteriorarion to
any part of pipe.
Any dent that decreases the cross-secrion Pipe repaired or replaced.
area of pipe by more than 20%.
Open Ditches Trash and Debris Trash and debris exceeds 1 cubic foot per Trash and debris cleared
1,000 square feet of ditch and slopes. from ditches.
Sediment Accumulated sediment that exceeds 20% Ditch cleaned/flushed of all -
of the design depth. sediment and debris so that
matches design.
Vegetation Vegetation that reduces free movement of Water flows freely through
water through ditches. ditches. ,
Side Slopes Erosion Eroded damage over 2 inches deep where Slopes should be stabilized
cause of damage is still present or where by using appropriate erosion
there is potential for continued erosion. control measure(s): e.g.,rock
' i_ reinforcement,planring of
grass, compacrion.
ti_.
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44
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APPENDIX A
King County Runoff Time Series
(KCRT S) Input/Output D ata
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_
_
C� ��5�ws
.r-=Land use�Summary , - _ --- _ . ._ _ .
Till Forest 2.69 acres
Till Pasture 2. 55 acres
Till Grass t�.00 acres
Outwash Farest fl.00 acres
outwash Pasture 4.U0 acres
Outwuash Grass 0.00 acres
We�tland 0.�a a�res
Impervious 0.45 acres .
Total Area : 5.69 acres
Scale Factor : 1.�0 Haurly Reduced
Time Series: • - • -
' Compute Time series �
- - = Modify User Inpu�
��'f;l
� Land Use Surr�nar}f
Ti11 �ores�t 0.40 acres
Till Pasture t1.09 a�res
Till Grass.- 2.93 a�res
outwash �or�st 0.00 acres
� outwash Pasture 0.00 acres
j ou�tdvash Grass 0.00 acres
�vetland �.00 acres
Impervious 2.67 acr�s
To�tal Area : 5.69 a�res
Scal� Factor : 1.�0 Haurly Reduced
::�
�Time S�riQs: • -
; �,, i �er . Compute Time Series
� ri� � , Modify. User Input , . _ .
,:�-��; :.:.�.
;.�..��_..,.. _��x�w..��._.�.w.�,...��.�.o_.�:..�� _...._ _ ��.s...����.�.�.._ .v, �:,,_w__._._..�d_...._�._
,
Flow Frequency Analysis
Time Series File:predev.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates--- -----Flow Frequency Analysis-------
Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob
(CFS) (CFS) Period
0.422 2 2/09/O1 15:00 0.713 1 100.00 0.990
0.207 7 1/05/02 16:00 0.422 2 25.00 0.960
0.403 3 2/28/03 3 :00 0.403__ 3 10.00 0.900
0.124 8 8/26/04 2 :00 0.369 4 5.00 0.800
0.236 6 1/05/OS 8:00 0.363 5 3.00 0.667
0.389 4 1/18/06 16:00 0.236 6 2.00 0.500
0.363 5 11/24/06 4 :00 0.207 7 1.30 0.231
0.713 1 1/09/08 6:00 0.124 8 1.10 0.091
Computed Peaks 0.616 50.00 0.980
Flow Frequency Analysis
Time Series File:dev.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates--- -----Flow Frequency Analysis-------
Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob
(CFS) (CFS) Period ',
0.914 5 2/09/O1 2 :00 1.89 1 100.00 0.990 ',
0.706 8 1/05/02 16:00 1.11 2 25.00 0.960
1.11 2 2/27/03 7:00 1_05___ ____ __ 3___ 10_.00._-__0.900_ __--_-_-__-_
0.720 7 8/26/04 2 :00 0.966 4 5.00 0. 800 �
0.877 6 10/28/04 16:00 0.914 5 3.00 0.667 '
0.966 4 1/18/06 16:00 _ 0.877 6 2.00 0.500
----------
1.05 3 10/26/06 0:00 0.720 7 1.30 0.231 i
1.89 1 1/09/08 6:00 0.706 8 1.10 0.091
Computed Peaks 1.63 50.00 0.960 ,
�
. a
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Retention/Detention Facility
Type of Facility: Detention Vault
Facility Length: 80.45 ft
Facility Width: 80.45 ft
Facility Area: 6472 . sq. ft �
Effective Storage Depth: 6.80 ft
Stage 0 Elevation: 100.00 ft
Storage Volume: 44008. cu. ft
Riser Head: 6. 80 ft
Riser Diameter: 12.00 inches
Number of orifices : 2
Full Head Pipe
Orifice # Height Diameter Discharge Diameter
(ft) (in) (CFS) (in)
1 - 0.00 1.47 0.153
2 4.85 2.74 0.284 6.0
Top Notch Weir: None
Outflow Rating Curve: None
Stage Elevation Storage Discharge Percolation
(ft) (ft) (cu. ft) (ac-ft) (cfs) (cfs)
0.00 100.00 0. 0.000 0.000 0.00
0.02 100.02 129. 0. 003 0.007 0.00
0.03 100.03 194. 0. 004 0.010 0.00
0.05 100.05 324. 0.007 0.013 0.00
0.06 100.06 388. 0.009 0.015 0.00
0.08 100.08 518. 0.012 0.016 0.00
0.09 100.09 563. 0.013 0.018 0.00
0.11 100.11 712. 0 .016 0.019 0.00
0.12 100.12 777. 0 .018 0.021 0.00
0.24 100.24 1553. 0 .036 0.029 0.00
0.35 100.35 2265. 0.052 0.035 0.00
0.47 100.47 3042 . 0.070 0.040 0.00
0.56 100.58 3754. 0.086 0.045 0.00
0.70 100.70 4530. 0. 104 0.049 0.00
0.81 100.81 5242. 0.120 0.053 0.00
0.93 100.93 6019. 0.136 0.057 0.00
1.04 101.04 6731. 0.155 0.060 0.00
1. 16 101.16 7507. 0.172 0.063 0.00
1.28 101.28 8284. 0.190 0.066 0.00
1.39 101.39 8996. 0 .207 0.069 0.00
1.51 101.51 9772. 0.224 0.072 0.00
1.62 101.62 10484. 0.241 0.075 0.00
1.74 101.74 11261. 0.259 0.077 0.00
1.85 101.85 11973 . 0.275 0.080 0.00
1.97 101. 97 12749. 0.293 0.082 0.00
2.08 102.08 13461. 0.309 0.085 0.00
2.20 102.20 14238. 0.327 0.087 0.00
2.31 102 .31 14950. 0.343 0.069 0.00 I
2.43 102 .43 15726. 0.361 0.091 0.00 I
2.54 102 .54 16438. 0.377 0.093 0.00 �
2.66 102 .66 17215. 0.395 0.096 0.00 !,
2 .77 102 .77 17927. 0 .412 O.j)98 0.00 ''
� 2 .89 102 . 69 18703 . 0 .429 0.100 0.00
3.00 103 .00 19415. 0.446 0.102 0.00
3.12 103 .12 20192. 0.464 0.104 0.00
3.23 103 .23 20904. 0.480 0.105 0.00
3.35 103.35 21680. 0.498 0.107 0.00
3.46 103 .46 22392 . 0.514 0.109 0.00
, 3.58 103 .58 23169. 0.532 0.111 0.00
3.70 103 .70 23946. 0.550 0.113 0.00
3.81 103 .81 24657. 0.566 0.114 0.00
3 .93 103.93 25434. 0.584 0.116 0.00
4 .04 104.04 26146. 0 .600 0.118 0.00
4.16 104.16 26923 . 0.618 0.119 0.00
4.27 104.27 27635. 0.634 0.121 0.00
4.39 104.39 28411. 0.652 0.123 0.00
4.50 104.50 29123 . 0.669 0.124 0.00
4.62 104.62 29900. 0.686 0.126 0.00
4.73 104 .73 30612. 0.703 0.128 0.00.
'' 4.85 104 .85 31388. 0.721 0. 129 O.Oa
4.88 104.88 31582. 0.725 0.131 0.00
4.91 104.91 31776. 0.729 0.137 0.00
4 .94 104.94 31971. 0.734 0.147 0.00
4. 96 104.96 32100. 0.737 0.162 0.00
4. 99 104.99 32294. 0.741 0.177 0.00
5. 02 105.02 32488. 0.746 0.198 0.00
5.05 105.05 32682. 0.750 0.221 0.00
� 5.08 105.08 32877. 0.755 0.229 0.00
5.19 105.19 33589. 0.771 0.253 0.00
5 .31 105.31 34365. 0.789 0.273 0.00
5 .42 105.42 35077. 0.805 0.291 0.00
5 .54 105.54 35854. 0.823 0.307 0.00
5.65 105. 65 36566. 0.839 0.322 0.00
I 5.77 105.77 37342 . 0.657 0.336 0.00
5. 88 105.88 38054. 0.674 0.349 0.00
6.00 106.00 38831. 0.891 0.362 0.00
6.12 106.12 39607. 0. 909 0.374 0.00
6.23 106.23 40319. 0. 926 0.385 0.00
6.35 106.35 41096. 0.943 0.396 0.00
6.46 106.46 41808. 0.960 0.407 0.00
6.58 106.58 42584. 0.978 0.417 0.0�
6.69 106.69 43296. 0.994 0.42B 0.00
6.80 106. 80 44008. 1.010 0.437 0.00
6.90 106.90 44655. 1.025 0.753 0.00
7.00 107.00 45302. 1.040 1.320 0.00
7.10 107.10 45950. 1.055 2 .060 0.00
� 7.20 107.20 46597. 1.070 2. 860 0.00
7.30 107.30 47244. 1.085 3 .150 0.00
7.40 107.40 47891. 1.099 3.410 O.00
7.50 107.50 48538. 1.114 3 .660 0.00
7.60 107.60 49186. 1.129 3 .880 O.00
7.70 107.70 49833 . 1.144 4.090 O.OG
7.80 107. 80 50480. 1.159 4.290 0.00
7.90 107.90 51127. 1.174 4.490 0.00
8.00 106.00 51774. 1.189 4.670 0.00
8.10 108.10 52421. 1.203 4 .850 0.00
8.20 108.20 53069. 1.218 5.010 0.00
8.30 108.30 53716. 1.233 5.180 0.00
8.40 108.40 54363. 1.248 5.340 0.00
8.50 108.50 55010. 1.263 5.490 0.00
8.60 108.60 55657. 1.278 5.640 0.00
8.70 108.70 56304. 1.293 5.780 0.00
Hyd Inflow Outflow Peak Storage ',
Target Calc Stage Elev (Cu-Ft) (Ac-Ft)
1 � 1.89 ******* 1.42 7.01 107.01 45393. 1.042
2 ' " 0:91 0.42 0.43 6.68 106.68 43243 . 0.993
3 0.91 ******* 0.35 5.92 105.92 38308. 0.879
4 1.11 ******* 0.29 5.40 105.40 34939. 0.802 �i
5 0.97 ******* 0.29 5.39 105 .39 34878. 0.801 �
6 0.57 ******* 0.12 4.12 104 .12 26656. 0.612 I
7 0.71 ******* 0.10 3.10 103 .10 20061. 0.461 '
8 0.72 ******* 0.08 2.04 102.04 13172 . 0.302
----------------------------------
Route Time Series through Facility . �
Inflow Time Series File:dev.tsf -
Outflow Time Series File:rdout
Inflow/Outflow Analysis '
Peak Inflow Discharge: 1.89 CFS at 6:00 on Jan 9 in Year 8
Peak Outflow Discharge: 1.42 CFS at 9:00 on Jan 9 in Year 8 �
Peak Reservoir Stage: 7.01 Ft '
Peak Reservo�r Elev: 107.01 Ft
Peak Reservoir Storaae: 45393. Cu-Ft ,
. 1.042 Ac-Ft
Flow Duration F�om Time Series Fiie:rdout.tsf
Cutoff Count Frequency CDF Exceedence_Probability
CFS � � $
0.006 39603 64.584 64.584 35.416 0.354E+00
C.O18 4709 7.679 72.264 27.736 0.277E+00
0.030 4768 7.776 80.039 19.961 0.200E+00
0.042 3650 6.279 86.318 13 .682 0.137E+00
0.054 2906 4.739 91.057 8.943 0.894E-01
0.066 2103 3.430 94.486 5.514 0.551E-01
0.078 1142 1.662 96.349 3 .651 0.365E-01
0.090 645 1.378 97.727 2 .273 0.227E-01
0.102 513 0.637 98.563 1.437 0.144E-01
0 .114 379 0.618 99.181 0.819 0.819E-02
0 .126 298 0.486 99.667 0.333 0.333E-02
0 .138 73 0.119 99.786 0.214 0.214E-02
0 .150 10 0.016 99.803 0.197 0.197E-02
0.162 6 0.010 99.812 0.188 0.188E-02
0.174 7 0.011 99.824 0.176 0.176E-02
0.166 5 0.008 99.832 0.168 0.168E-02
0 .198 3 0.005 99.837 0.163 0.163E-02
0.210 1 0.002 99.839 0.161 0.161E-02
0.222 6 0.010 99.848 0.152 0.152E-02
0.234 7 0.011 99.860 0.140 0.140E-02
0.246 8 0.013 99.873 0.127 0.127E-02
0.258 11 0.016 99.891 0.109 0.109E-02
0.270 11 0.018 99.909 0.091 0.913E-03
0.282 11 0.018 99.927 0.073 0.734E-03
0.294 11 0.018 99.945 0.055 0.554E-03
0.306 3 0.005 99.949 0.051 0.506E-03
0.318 3 0.005 99.954 0.046 0.457E-03
0.330 4 0.007 99.961 0.039 0.391E-03
0.342 3 0.005 99.966 0.034 0.342E-03
0.354 6 0.010 99.976 0.024 0.245E-03
0.366 3 0.005 99.980 0.020 0.196E-03
0.378 1 0.002 99.982 0.018 0.179E-03
0.390 2 0.003 99.985 0.015 0. 147E-03
0.402 2 0.003 99.989 0.011 0.114E-03
0.414 4 0.007 99.995 0.005 0.489E-04
0.426 2 0.003 99.998 0.002 0.163E-04
Duration Comparison Anaylsis
Base File: predev.tsf
New File: rdout.tsf
Cutoff Units: Discharge in CFS
-----Fraction of Time----- ---------Check of Tolerance-------
Cutoff Base New �Change Probability Base New �Change �
0.118 � 0.70E-02 0.53E-02 -23 .9 � 0.70E-02 0.118 0.116 _2 .2 t ' 6 D
0.142 � 0.52E-02 0.21E-02 -60.5 � 0.52E-02 0.142 0.119 -16.4
0.165 � 0.39E-02 0.18E-02 -53 .1 I 0.39E-02 0.165 0.123 -25.3 ,
0.189 � 0.29E-02 0.17E-02 -41.1 � 0.29E-02 0.189 0.126 -32.0
0.212 � 0.20E-02 0.16E-02 -20.3 � 0.20E-02 0.212 0.145 -31.4
0.235 � 0.14E-02 0.14E-02 -4.5 � 0.14E-02 0.235 0.232 -1.2
0.259 � O.10E-02 0.11E-02 1.6 � O.10E-02 0.259 0.259 0.3
0.282 � 0.83E-03 0.73E-03 -11.8 � 0.63E-03 0.282 0.276 -2 .3
0 .306 � 0.62E-03 0.51E-03 -18.4 � 0.62E-03 0.306 0.285 -6.6
0 .329 � 0.46E-03 0.39E-03 -14 .3 � 0.46E-03 0.329 0.319 -2 .9
0 .352 � 0 .24E-03 0.26E-03 6.7 � 0.2�E-03 0.352 0.354 0,4
0 .376 � 0.15E-03 0.18E-03 22.2 � 0.15E-03 0.376 0.395 5.�
0 .399 � 0.65E-04 0.11E-03 75.0 � 0.65E-04 0.399 0.414 3 .7
Maximum positive excursion = 0.032 cfs ( 6.9�} '
occuring at 0.363 cfs on the Base Data:predev.tsf
and at 0.395 cfs on the New Data:rdout.tsf �
Maximum negative excursion = 0. 071 cfs (-34.8�) '
occuring at 0.202 cfs on the Base Data:predev.tsf
and at 0 . 132 cfs on the New Data:rdout.tsf
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'
APPENDIX B '��
Wetland Report
�
�
i
�
�
� � �_ TERRA ASSOCIATES, Inc.
�`""��"`" Consultants in Geotechnical Engineering, Geology
._. �. and
Environmental Earth Sciences
December 13, 1999
Project No.T--4011
Mr.Robert Wenzl
Belmont Homes,Inc.
P.O.Box 2401 .
Kirkland, Washington 98083 �
Subject: Wetland Evaluation Report
Vineyard Court
Renton,Washington .
Dear Mr. We;izl:
As requested, �ve have conducted a wetland evaluation of the Vineyard Court property located east of Union
Avenue NE, south of N� 7th Street, and north of NE Sth Street in Renton, Washington. The purpose of otu work
was to e�•atuate existin; site conditions and delineate the boundaries of the wetland areas lrnown to be present on
the propem�. Our site evaluation and delineation of wetland conditions was conducted using the rourine ,
methodolo�� outlined in the Federal Manual for ldent�ing and Delineating Jtrrisdictional Wetlarrds (1959), as il
required by the City of Renton. These procedures involve analyses of vegetarion patterns, soil conditions, and
surface hydrologry to distinguish between wetland and upland areas.
We originally delineated the northern extent of Wetland A during a site visit on July 16, 1997. Mead Gilman and �
Associates surveyed those flag locations. The southern portions of Wetland A and Wetiand B were evaluated
during our second and third site visits, on April 1� and 17, 1998. We made another site visit on February 25, �
1999, to review the delineation of the northern extent of Wetland A and to evaluate the extent of buffer I
disturbance. i�
PROCEDURES I
For the purpose of this study, we used the wetland definirion adopted by the Environmental Protection A�ency ''
(EPA) and the Army Corps of Engineers (COE) for administering Section 404 of the Clean Water Act.
According to this definition, wetlands are:
Those areas that are inundated or saturated by surface or groundwater at a frequency and duration i
sufficient to support, and under normal conditions do support, a prevalence of vegetation
typically adapted for life in saturated soil conditions. Wetlands generally include swamps,
marshes,bogs,and similar areas. .:,
12525 Wiilows Road, Suite 101, Kirkland, Washin ton 98034 � ;
Mr.Robert Wenzl
December 13, 1999
In accordance with th.is deiinition, a given area is designated as jurisdictional wetland if the hydrology results in
� inundated or saturated soils during the growing season, hydric soils are present, and the dominant vegetation is
hydrophytic.
Delineation procedures are based on dia�nostic em7ronmental indicators of wetland veeetation, wetland soils, and
wetland hydrology. These procedures, outlined in the Federal Manual for ldent fi�ing and Delineating
Jurisdictional �etlands (1989), are commonly lrno«n as the Tripie Parameter Method. By definirion, an area is
� designated as wetland when there are positive indicators for all three parameters.
' A listing of plant species has been developed for use in the methodology for delineating wetland areas. This
listing assi�ns plant species to one of five indicator status categories, ranging from Obligate wetIand species,
which almost al�-ays occur in �vetlands, to Upland species, which rarely occur in �vetlands. Under normal
�' conditions,hydrophytic vegetation is determined to be present if more than 50 percent of the dominant species are
in the Obligate (OBL),Facultative Wetland(FACR'), or Facultarive (FAC) indicator cateeories.
Diagnostic indicators of hydric soils are related to soil saturation, which leads to anaerobic conditions in the soil.
Under these conditions, decomposition of organic material is inhibited and soil mine:als are reduced, giving
characteristic soil colors that can be quantified by comparison with Munsell Soil Color Charts. A chroma of one
or less in unmottled soils or a chroma of rivo or less in mott]ed soils generally indicates a hydric soiI. In addition,
soils that are saturated during the growing season satisfy a criterion for hydric soils. �Ve used a hand auaer to
�' collect soil samples for determination of hydric soil criteria. y
, Wetland hydrolog}•is defined as inundated or saturated soil conditions for at least 5 percent(14 consecutive days)
� ' of the growin� season. If no water is present at the time of evaluation, other indicators may include topographic
Iow points or channels, flood debris, complete absence of vegetation, or presence of hydric soils. Standardized
data forms are available to record observations on each of these parameters. We completed data forms for the
Routine On-Site Determination�iethod. Copies of t::ese data forms are attached to this report.
i SITE CONDITIONS
' The approximately 7.18-acre irregularly shaped subject property is located east of Union Avenue 1�`E, as show-n
on Figure 1. Older single-family residences occupy adjacent properties to the south and west. Adjacent
properties to the north and east have recently been developed with sin�le-family residences as a part of the
Orchards proiect.
Currently, the subj�ct propert} is developed «-ith f��e s�.�all single-family residences. The remainde; of the
property is open forest dominated by Douglas fir (Pseudotsuga men�.iesii), big-leaf maple (Acer macrophyllum),
red alder (Alnus rubra), and black cottonwood (Popt�lus trichocarpa). The understory includes salmonb�rry
(Rubus spectabilis), salal (Gaultheria shallon), creambush oceanspray (Holodiscus discolor), and sword fem
(Polystrchzrm munitum). The open areas around the residences include grassy lawns and some Iandscaping.
There are thickets of Himalayan blackberry (Rubus discolor) and Scot's broom (Cytisus scoparius) in disturbed
areas. Other plant species observed on the property are listed on Table l.
.
Pro�ect No.T-4011 .
Page No. 2
Mr.Robert Wenzl
December 13, 1999
The area around the northern residence has recently been cleared to remove large quantities of debris. The
clearing removed virtually the entire understory, which was dominated by Himalayan blackberry, with lesser
amounts of salmonberry,red elderberry(Sambucus racemosa), and Indian plum (Oemleria cerasiformis).
The Soil Survey� of King County Area, Washington, U.S. Soil Conservation Service, 1973 maps the soils on the
property as Alderwood gravelly sandy loam. The Alderwood soil type is characterized as a moderately well-
drained soil and is not included on the I�Tational Technical Committee on Hydric Soils (NTCHS) lisring of hydric
soils.
Topographically, the site slopes gradually dow�n from a high point at the east side of the property to lo�ver points
along the western border. A low swale crosses the southeast corner of the site. The site is located on a plateau at
approxir:zatel�� Elev. 400.
WETLA�`D :�RE:�S
T«<o areas «rit?-: wetla^d conditions are located on the subject property, as show�n on Fieure 2. Wetland A is
located in the low areas in the northwest corner and extends southwest off the property. The wetland extends
back onto the subject property in the south�vest. Terra Associates, Inc. delineated the boundaries of these
wetlands across the property. Mead Gilman and Associates, Inc. surveyed the delineation flags. This delineation
was conducted using procedures outlined in the Federal Manual for ldentifying and Delineating Jurisdictional
Wetlands (1989). However, using procedures in the Corps of E'ngineers Wetlands Delineation Manual (1987)
would result in :�o chanQe in this delineation.
Wetland A
��'etland A extends from the northwest properry tine southwest to Union Street. Two gravel roads cross over the
wetland. The first gravel road runs east to west at Lot 39, and the second is at NE 6th Street. The total area of
wetland on and ofi the property is estimated to be less t�an five acres.
This wetland is dominated by forested vegetation. The most abundant �-ee species include black cotton�vood,
Oregon ash{FraYinars latifolia), and red alder. Scouler���illow (Salix scouleriana}, Pacific ninebark(Phvsocarpus
capitatus), and salmonberry are common shrubs. The dominant herbaceous vegetation includes slough sedge
(Carex obnzrpta), lad��-fern (Athyrium filix fenrina), reed canary grass (Phalaris arundinacea), and creepino
buttercup (Ranunculirs repens). More details are pro�Tided on Data Forms 4, 5, 7 and 9.
Soil colors in the wetland area ranged from black (10YR2/1) with no mottles to dark brown (10YR3/3) with
traces of dark yellowish brown (10YR3/4) mottles. Soil samples throughout the wetland had a histic epipedon,
_ which is a very high organic content in the surface layer. This feature is a thin layer of peat over mineral soil.
The soils were generally moist to the surface throughout the wetland area, and saturated or inundated in some
areas during our site visit in April 1999. Soils in the adjacent upland areas were dark brown (10YR3/3) to dark ,
yellowish brown (10YR3/4)without mottles.
:
Project No.T-4011
Page No. 3 '
Mr. Robert Wenzl
December 13, 1999
Hydrologically, this wetland appears to be supported primarily by a shallow seasonal groundwater table with
some surface flow through an intermittent stream channel from properry to the north. Nearly all of the wetland
was inundated during our site visit in February 1999, during an extremely wet rainy season. Concrete culverts
- were constructed that allowed stream flow from the north to the south, through the gravel roads.
The continuation of this �vetland on property to the north has been heavily disturbed by activities related to the
construction of single-family residences in the Orchards development. A dike was installed across the wetland,
with a culvert that allowed surface flow. This dike might follow the route of an old a avel driveway. The
wetland upstream from the dike was altered for use as a stormwater detention facility.
The outlet from this wetland is a culvert at the southwest comer of the site at Union Avenue NE, south of 6th
S�-eet NE. The outlet from this wetland is not located on the subject property. This culvert leads into the storm
drainage system under Union Avenue NE. -
A portion of the buffer on the property was damaged as a result of the clearino of debris. The portion of the
wetland buffer impacted is discussed our Wetland Delinearion Report, dated March 23, 1999.
There has also been relatively recent fills put into the southeast edge of the wetland, and some trees have been
removed from the wetl2nd.
W'etland A has moderate to low functional values, primarily because of its relatively small size, disturbed
boundaries, and isolated condition in a residential area. Base flow/groundwater support, water quality
improvement, natural biological support, and specific habitat functions have moderate values. Flood/storm�vater
control has a high value. Erosion/shoreline protection, overall habitat functions, and culturaUsocioeconomic
values have a low ratinQ. Details of the funcrional analyses are provided on Table 2. ,
Usin� the U.S. Fish and Wildlife Service (USF`VS) wetland classification system (Co�vardin et al., 1979), 'i
Wetland A includes areas of palustrine forested wetland with broad-leaved deciduous vegetation (PFO1) and I
palustrine scrub-shrub wetland with broad-leaved deciduous vegetation (PSS1). This area is not mapped on the
National YVetland Inventory Map (Renton quadrangle, USFWS, 1988) or in the King County Sensitive Areas Map ;
Atlas. '
It is our interpretation of the City of Renton Wetlands Management Ordinance that this wetland should be rated as
a Class 2 �vetland, due to its size. The wetland does not have features required for a Class 1 wetland. The City of
Renton requires that Class 2 wetlands be provided with 50-foot wide buffers. ,
The northern portion of Wetland A has been significantly disturbed by a large dike near the northern property
boundary and by a gravel driveway across the southern boundary. Construction of the Orchards project and the
use of this area for storm detenrion disturbed the upstream continuation of this wetland on adjacent property to the
north. The wetland and its buffer were also disturbed by past dumping of trash on the site and blackberry
invasion. It is our understanding that the City of Renton previously approved a Class 3 classification for this
portion of the wetland. The City of Renton requires a 25-foot wide buffer for Class 3 wetlands.
�
Project No.T-4011
Page No.4 -
� Mr. Robert Wenzl
December 13, 1999
, Wetland B
Wetland B is located in the southeast corner of the Vineyard Court site. The entire perimeter of this wetland was
delineated. This wetland is approximately 3,920 square feet(0.09 acres). '
Wetland B is dominated by relatively young broadleaf deciduous tree species, including red alder and Scouler
willow. Hardhack spirea (Spiraea douglasii), salmonberry, and pea-fruit rose (Rosa pisocarpa) are common
shrubs. Data Form 1 provides more detailed information. The dominant herbaceous vegetation is reed canary
grass and soft rush(Juncus effzrsirs).
Soil colors in this wetland area are generally black (10YR2/1) without mottles, but oxidized root zones are
preseat. These soils were saturated at a depzh'of about 20 inches during our site visit in April 1999. Soils in the
adjacent undisturbed upland area are dark brown(10YR3/3) without mottles.
Hydroto�ically, this wetland appears to be supported by a shallow seasonal groundwater table. There is some
surface runoff through a ditch from the Orchards development on adjacent property. Any surface flow into this
! area appears to infiltrate quickly, and there is no surface outlet. The southwest end of this wetland is adjacent to
landscaped baci.yards.
Wetland B and its buffers have been hea��ily disturbed by past activiries. The southern edge of the wetland is
close to a fence and landscaped yards. An old residence and eravel parking area are close to the northern edge of
the �vetland. The Orchards development has cleared and graded the adjacent propem� to the east. The young
vegetation in the wetland indicates that it was probably cleared between 10 and 15 years ago.
Wetland B has generally low functional values,primarily because of its very small size, disturbed conditions, and
isolated condition in a residential area. Flood/stormw�ater control, base flowlground�vater support, and �vater
quality improvement have moderate values. Erosion/shoreline protection, natural biological support, overall
habitat functions, specific habitat functions, and culturaUsocioeconomic values have a low rating. Details of the
functional analyses are provided on Table 2.
Using the USFWS wetland classification system (Co«-ardin et al., 1979), Wetland B is dominated by palustrine
forested wetland with broad-leaved deciduous vegetation {PFO1), although the trees are very young and of
relarively low stature. This area is not mapped on the Nalional Wetland Inventory tLlnp (Renton quadrangle,
USFWS, 1988) or in the King Cozmry Sensitive Areas Map Atlas.
It is our interpretation of the City of Renton Wetlands Management Ordinance that this wetland sarisfies the ,
severely disturbed cnteria to be a Class 3 wetland. However, the City of Renton Code specifies that Class 3 ��,
wetlands must be greater than 5,000 square feet in size (Section 4-32-3.D.3). This wetland area is less than 5,000 ',
square feet in size,and therefore, is unregulated by the City of Renton. !
� �
. I
Project No.T-4011
Page No. 5
Mr.Robert Wenzl
December 13, 1999 I
Restoration of Wetland A II
As discussed, there was recent fill put into the southeast edge of the wetland and buffer. Some u�ees and nearIy
the entire understory were removed from this area. The approximate location of the fill is shown on Figure 2.
The fill should be removed and the impacted wetland and buffer should be replanted with narive vegetarion.
Vegetation should include native species such as western red cedar, black cottonwood, red-osier dogwood
(Cornus sericea), wild rose (Rosa pisocarpa), and willow(salix}. A final restoration plan will be prepared when
the final grading plans are available for Vineyard Court.
We trust this information is sufficient for your current needs. If you have any questions or require additional
information,please ca1L
Sincerely yours, -
TERRA ASSOCIATES,INC.
�� p �
Garet P. Munger
Proiect Scientist
Encl: Table 1 -Plant Species Observed
Table 2 -Wetland Functional Value Summary
Figure 1 -Vicinity Map
Fi;ure 2 -Wetland Locatio;�Map �
Data Forms (10) ',
II
I
:
. . � Project No.T-4011 -
. � ' Page No. 6 :
TABLE 1
PLANT SPECIES OBSERVED
Vineyud Court
Renton,Washington
Scientific Name Common Name Status* L'nland Wetland
TREES
Acer»iacrophyllum Bi�-leaf maple FACU X X
Alnus ruGra Red alder FAC X X
Fra.einus latifolia Oregon ash FACW X
Popultts tric{:ocarpa B(ack cottonwood FAC X X
Prunus en�arginata Bitter cherry FACU X
Pseudouuga menziesii Douglas fir FACU X
Salir lcuiandra Pacific willow FACW X
Thuja plicata Western red cedar FAC X X
Ulmus sp. Elm X
SHRUBS
Acer circiitancm Vine maple FAC X X
Cornus srolaiifera Red-osier dogwood FACW X X
Corylt�s cornuta Beaked hazelnut FACU X '
Cratae;us monogyna One-seed hawthorn FACU X X
Cratne,ccs dot�glasii Black ha�vthorn FAC X X
Cytisus scoparic�s Scot's broom UPL X
Gault/:eria sltallon Salal FACU X
Holodiscus discofor Creambush ocean-spray UPL X X
Ilex aquifoliu»t English holly UPL X X
Oemleria cerasiformis Indian plum UPL X X
ll�lahonin nervosa Cascade Oregon grape UPL X
Plrysocnrpc�s ccpitatus Pacific ninebark FACW X X
Rhamnus purshiana Cascara FAC X
Ribes lacustre Prickly curcan[ FAC X
Rosa pisocarpa Peafruit rose FAC X X
Rtcbirs discolor Himalayan blackberry FACU X X
Rubus laciniatus Ever�reen blackberry FACU X
Rubiis parviflorus Thimbleberry FAC X
Rubus spectabilis Salmonberry FAC X X
Rubus ttrsint�s TrailinQ blackberry FACU X X
SaliY scouleriana Scouler's willow FAC X
Salix sp. Willow X
Sambucus racen:osa Red elderberry FACU X
Spiraea douglasii Hardhack spirea FACW X X
Sorbus aucuparia European mountain ash UPL X
Syntplioricarpos albus Snowberry NI X X
Vacciniuni parvifolium Red huckleberry UPL X
HERBS
Agrostis tenuis Colonial bentgrass UPL X
Atftvrium filix femina Lady fern FAC X X
Bromi�s vulgaris Columbia brome UPL X
Care.r sp. Sedge X
� {Continued on next page)
TABLE 1 (Continued)
PLANT SPECIES OBSERVED ON-SITE
Vineyard Court
Renton,Washington
Scientific Name Common Name Status* Ualand Wetland
HERBS (Continued)
Carex canescens Gray sedge FACW X
Carex obnupta S1ouQh sedge OBL X
Circaea alpil:a Enchanter's nightshade FAC X
Cirsium vulgare Bull thistle FACU X
Dacrylis glomerata Orchard�rass FACU X
Dicentra formosa Bleedin�heart FACU X
Epilobiuni angustifotium Fireweed FACU X
Epilobiunt paniculatum �'illow-herb UPL X
. Geraniun: robertianum Robert geranium UPL X X
- Geum mncrophyllum Lar�e-leaved avens FACW X X
Glyceria elata Tall mannaa ass FACW X
Graminae spp. Grasses X X
H}•pochaeris radicara Hairy cat's ear UPL X
Jiuicus efficsus Soft rush FACW X
Lapsana cominc�nis Nipplewort UPL X
I.olii�m pere�ute Perennial rye�rass FACU X
Lytlirum salicaria Purple loosestrife FACW X
Maia�it{:emunt dilatatum False lily-of-the-valley FAC X
Montia siGirica Western spring beauty FAC X
Phalaris n�•ii�idi�iacea Reed canary grass FACW X X
Plantago la�tceolata Rib plantain FAC X
Plantngo major Broadleaf plantain FACU X
Poa pratensis Kentucky blue�rass FAC X X
Polygoncun sachalinense Giant knotweed FACU X
Pohsticfti�»i mt�nilunt Sword fern FACU X X
Pteridiurn aquilinwn Bracken fern FACU X
Ran�uici�lus repens Creeping buttercup FACW X X
Run�ex crispcts Curly dock FAC X k
Scirpus microcarpus Smail-fruit bulrush OBL >
T'arazacum officinale Common dandelion FACU X
Trifolium pratense Red clover FACU X
7'rifolium repens White clover FAC X
Trilliuin ovatum Western trillium FACU X
Typl:a latifolia Cattail OBL .�
Verortica antericana American brooklime OBL X
*Wetland Indicator Status:
OBL Obligate wetland-almost always occurs in wetlands. _
FACW Facuitative wedand-usually occurs in wedands,but may be found in uplands.
FAC Facultative-equally Iikely to occur in wetlands or uplands.
FACU Facultative upland-usually occurs in uplands,but may be found in wedands.
UPL Upiand-almost always occurs in uplands.
Blank Insufficient information to assign a status.
� . -
TABLE 2
� � WETLAND FUNCTIOh'AL VALUE SLmIMARY
l Vinevard Court
Renton,«ashington
��'etland A
Functional
Wetland Function�l� Rating Comments
Flood/Stormwater Control High Relatively small size,depression near headwater, moderate forest
cover,culverted outlet,upper third of drainase.
Base Flow/Groundwater SuppoR Moderate Relatively small size,depression near headwater,moderate forest
cover,seasonally flooded or satura[ed,possible fish populations
� downstream.
Specific Habitat Functions Moderate Poor invertebrate and fish habitat, mode:ate quality habitat for
amphibians,birds,and mammals.
Water Quality Improvement Moderate Moderate flow through site,moderate��e�etative cover, upscream
basin is heavily developed,moderate runoff retention.
Natural Biological Support Moderate Relatively small size, moderate veQetation structure,two habitat
t}Pes,some invasive species,moderate species diversity,moderate
productivity and organic accumulation,low or�anic export,some
special habitat features, buffers hiehly cisturbed, isolated from
upland habitats. �
Overall Habitat Functions Low Relatively small size, moderate habicat diversity,low sanctuary or
refu�e potential.
Erosion/Shoreline Protection Low Relatively narrow wetland with sparse vees and shrubs above
OHR'M,heavily developed boundar}•area.
CulturaUSocioeconomic Low Lo�v educationai opportunities, low aeschetic value,no fish
resources,no historical or archeolo=ical resources,no recreational
opportunities,private ownership,not near open space.
Wetland Area Less than ten acres
Wetland Community Type(s)�� Palustrine forested, broad-leaved deciduous(PFO1) Palustrine
scrub-shrub, broad-leaved deciduous(PSS 1)
Wetland Cate�ory Renton Class 2 Wetland
��� Based on Coo[:e,S.S. (1996) Wetland and Buffer Funcrio�is Semi-Quantitarive.�ssessn:er.t:�lethod
a� Cowardin et al (1979) Classificatio�i of Wetlands a�td Deepwater Hab�::;::,
. ' " -_
TABLE 2(Continued)
WETLAND FUNCTIONAL VALUE SUMMARY
Vineyard Court
Renton,Washington
�Vetland B
Functional
Wetland Function�l� Ratin� Comments
Flood/Stormwater Control Moderate Very small size,isolated depression,moderate forest cover,no
outlet,upper third of drainage.
Base Flow/Groundwater Support Moderate Very small size,isotated depression,moderate forest cover,
. temporarily flooded or saturated, no fish populations downstream. ,
Erosion/Shoreline Protection Low Very narrow wetland with sparse trees and shrubs at OHW�I,
heavily developed subcatchment.
Water Quality Improvemept Moderate Slow flow through site,moderate veaetative cover,upscream basin
is heavily developed,moderate runoff retention.
Natural Biolo�ical Support Low Very small size, moderate ve�etation structure,one habitat type,
some invasive species, moderate species diversity,moderate
productivity,lo�v organic accumulation, low organic export,few
special habitat fea[ures,buffers hi�hly disturbed,isolated from
upland habitats.
Overall Habitat Func[ions Low Very small size,low habitat diversity,and low sanctuary or refuge
potenciaL
Specific Habitat Functions Low Poor invertebrate,fish,and mammal habitat,moderate quatity
habitat for amphibians and birds.
CulturaUSocioeconomic Low Low educational opportunities,low aesthetic value,no fish
resources,no historical or archeolo�ical resources,no recreational
opportunities,private ownership, not near open space.
- �edand Area Less than 5,000 square feet
� ��, Wedand Community Type(s)��� Palustrine forested, broad-leaved decic��ous (P�01; �
� Wetland Category Renton Class 3 Wedand(Unregulatedl
' «� Based on Cooke,S. S.(1996) Wetland and Buffer Functions Semi-Qc�antitattve Assessment Metii�
i �
�� Cowardin et al (1979)Classificatic
I
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Reference: The Thomas Guide, Metropolitan Puget Sound, Pages
626 and 656, 2000 Edition.
� � T E R RA VICINITY MAP
.: :;-:��.� Vineyar`d Court
��'� � ASSOCIATES Rentort, Washington
Environmentol Consultants Proj. No. T-4011 Dote Dec. 1999 Figure 1
A - _ .
� -- - - - - ,� • � , ---�--=-� ---�,�„_, - �
� -- - � -�-
� � — - - � - . _ - -, . .. _ . . ---- ____
� -- - ► ----:- ." . ' � "' , • DP 10 __ � � _
�--.-- ._ .{ ..- " ." . ��:.:�- ::__� . ___I _ � (� �- -� _ _ . � � -
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• D � -
� _- _. � _ � - ------ - - - � _ __ _._ _. ._ � � � DP8� � �� ,�. �
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r i . _ � _ - ---- -" . .. .. . _._ , , �i � p ' -- ,,,0 (
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� � _. � 0 p�, r .� x i
� � ! ' _;:,� , ,.,r�,,, � ;
~ i � WETLAND „, g =
�,.,
� !
� i ! . � ; .0�,� O }[.fe+ ^ r ; .
�{ arfY�:!
� (
► � ! ( ' 1
� '• • DP5 � � DP6 !
i � i
� � � _ . ,, 1 " ,� i
� � ! EXISTING GRAVEL ROAD ' "e- , . �# �
�. � ----------------------- ------ ,,,, ,.,�,, „ �, N ; .
; ; _ -----------=� � ,��� ,„� . ; — Wetland Boundary
�` � � �i � ��� i i -- Appro�mate Wetland Bour
.
. � �____ . ___ ____ :: i ��� � ' i �
�~ ��_ � . • Appro�umate Data Point Lo
:.,, ; i � ;� � i _.—.J
i ! � ' � �
_ ; � u � n i � j
� ; � ,;� � �
� i Fill*-Fill to be removed from wetland � ' .
i , � � �
" j � _ See Terra Associates report T-3718-3, � �----. - - - - - - - -
� ! dateri December 3, 1999,for the results of ,► j �
�" ! � environmental testing. Wetland shall be `�I '
; 1 restored following removal of fill. " �
.. � �I s'� € ; ,.ti �--� �
j � ' I
� i j I O�
� J. .,o ��:� ���
t: � � � ;' , EXISTING GRAVEL ROAD .�� �"��-"''�� '��
� � t � , . . � . '_ �---- � . . . � � �='
� � � —�-�—�- ( NE 6th Street
! C :)..;� � • DP4 ~ � ?Orp,a: � � 00� `
;.. ,� a ,�,. �-�-- '�' I ��_�. --'.r-= APPROXIMATE SCALE
;; _• � j ,��- .�� ,• ;• „a0 O ,� \\� . ,.�. p,.� ,;.,1 !,•l 30 G 30
, . t ` �� �— ��� DP3 �,.r � T �t
` �� < � / / ,R ��.----__. � %" i
c� i ,.,�NETLAND A ! � �� ��;{,y- j
i � �S� ., ' FILL* I ` ."� "r'�.,� .„t !
� � ��' �� � ) -��""��,., ��•. '��� i;
Z �. O�� � � I :, {�� . .
�: �� m � ',,._ � .„ ;; .
i �� --�. � � . � ��+ ''� �; �
^ i � -' - .._._.__. � : � `�f� i -
... i � • ; . ' � � i
, J. � �., � • — � - . .
—, � � ,� � c ' �4'" �;� � � • DP2 i
:.. � I ,,, s°° �� � DP1 +j � � WEfLAND LOC�
.r „�,� ' , , -:s::�� TERRA Vineyard
e� � ��� � �� ETLAND � ..'Y:•� � � Renton,� Wc
; ' ; � � o�, � �. . . , ,•-. -� - _ ASSOCIATES
M � \ ~
� _ . - � t� ,_ �'-.� l - ! . . ." �� I -� '�'. • Environmental Consultants. - Proj.No. T-4011 Date [
, . � . - _ . _ ., . - - - • . . _ - . - _
� : ^ _ - _ . . ;T _ � _ - . . _ . .
_ -----�
i '
DATA FORM
ROUTINE ONSITE WETLAND DETERMINATION
1987 1989
Describe General Site Forested wetland Data Point No.: 1
Conditions:
Site Disturbance? Young broadleaf trees, close to landscaped yard, Locarion: �10'S of TA-8 A
inlet channel has been ditched om ad'. ro er .
VEGETATION
o � � o � �
Dominant Plant Species ° � � Dominant Plant Species � � r
c � v� _ � v�
�
1 Sa/rx scouleriana FAC T $ Glyceria elvta FACW H
2 Alnus nt6ra FAC T 9
_ 3 Sprraea douglasii FAC6i� S 10
4 Rubus sp'ectabilis FAC S 11
5 Rosa pisocarpa FAC S 12
6 Juncus e��sus FACGY H 13
7 Carex sp. H 14
Percent of dominant species that are OBL,FACV6', and/or FAC: !00%
Is the hydrophytic vegetation criterion met? Yes Rationale: >SO%F,�C, FACW, or OBL
SOIL
Soil Type: Alderwood grcL�velly sandy loam Hydric Soils List: Na
Histic Epipedon? �o Mottles? Ye.s Gleyed? No
Matrix Color: 10 YR 2/1 Mottle Colors: 10 YR 4i6 Depth: 10"
Other hydric soil indicators: Oxidi=ed root zones
Is the hydric soil criterion met? Yes Rationale: Low chroma with morrles
HYDROLOGY
Is the ground surface inundated? No Surface water depth: -
Is the soil saturated? Ye.s
Depth to free-standing water in probe hole: --20"
Other field evidence hydrology: Shallow swale wirh occasronal surface,�low ortginating on adacent property, bare soil,
matted leafdebris,smal!topographic basin.
Is the wetland hydrology criterion met? Yes Rationale: Evidence of inundation.
WETLAND DETERNIINATION
Are wetland criteria met? Y�s
Rationale for wetland decision: Positive indicators for a!!parameters.
Project Name: Vinevard Court Property Terta AssoCiates,Inc.
= Field Investigator(s): T. R Strong 12525 Willows Road, Suite 101
Project No.: T-4011 Date: ' 4/15/98 Kirkland,Washington 9803�
� - ,
:. ,
i
DATA FORM �
ROUTINE ONSITE WETLAND DETERMINATION
19871989
Describe General Site 2nd or 3rd growth forest Data Point No.: 2
Condirions:
- Site Disturbance? Close to house, landreaped yard,fill, etc. Location: —IS'N of TA-8-.4
VEGETATION
� N � � � �
Dominant Plant Species � � � Dominant Plant Species � � �
'� b '� '� b
� � � � � �
1 Prunus emarginata FACU T $ Rubus ursrnus F�CU V
2 Salix scouleriana FAC T 9 Polystichum munitum FACU H
3 Crataegus monogyna FACU S 10
4 Corylus cornuta FACU S 11 ',
5 Demleria cerasiforn:is FACU S 12
6 Rubus discolor FACU S 13
7 Sprraea douglasii FACN S 14
Percent of dominant species that are OBL,FACW,and/or FAC: 22%
Is the hydrophytic vegetation criterion met? 1Vo Rationale: <SO%FAC, FACW, or OBL
SOIL
Soil Type: Alderwood gravell}�sandv loam Hydric Soils List: No
Histic Epipedon? No Mottles? 1�'o Gleyed? No
Matrix Color: 10 YR 3/3 Mottle Colors: - Depth: 10"
Other hydric soil indicato*s: None
Is the hydric soil criterion met? No Rationale: High chroma, no morrles.
HYDROLOGY
Is the ground surface inundated? No Surface water depth: -
Is the soil saturated? No
Depth to free-standing water in probe hole: Dry to> 18". '
Other field evidence hydrology: Dry. Up slope from edge of wetland
Is the wetland hydrology criterion met? h'o Rationale: No evidence ojinundateon or saruration.
WETLAND DETERMINATION
Are wet]and criteria met? No
� - Rationale for wetland decision: No posrtive indicarors for any parameter
Project Name: Vinevard Court Property Terr3 Associates,Inc.
Field Investigator(s): T. R Strong 12525 Willows Road, Suite 101
Project No.: T-4011 I�ate: 4/IS/98 Kirkland,Washington 98034
�
i -
� • . . ' -
:_._ , . .
�
DATA FORM
ROUTINE ONSITE WETLAND DETERIVIINATION
19871989
Describe General Site 2nd growth mixed forest Data Point No.: 3
� Conditions:
- Site Disturbance? Close to driveway,fill, etc. Location: �l S'E of TA-13
VEGETATION
o ^ � o �„ �
Dominant Plant Species � � � Dominant Plant Species � � �
"'� L L
.�.. � [n � � (/]
1 Pseudotsuga menziesri FACU T $ Polystichum munitum FACU H
2 Prunus emarginata FACU T 9
3 Populus trichocar,^a _ FAC T 10
4 Oemleria cerasiformis FACU S 11
5 Rub:�s discolor FACU S 12
6 Gaiiltheria shallon FACU S 13
7 Rubus ursinus FACU V 14
, Percent of dominant species that are OBL,FACW, and/or FAC: 12 %
I Is the hydrophytic vegetarion criterion met? No Rationale: < SO%F.�C, FACW, or OBL
SOIL
Soil Type: Alderwood gravel!y san�y loam Hydric Soils List: A'o
Histic Epipedon? 1Vo Mottles? No Gleyed? No
Matrix Color: 10 YR 3/3 Mottle Colors: - Depth: 10"
. Other hydric soil indicators: ivone
Is the hydric soil criterion met? No Rationale: High chroma, no motrles.
Ii
�
FiYDROLOGY
Is the ground surface inundated? No Surface water depth: -
Is the soil saturated? No
Depth to free-standing water in probe hole: -
Other field evidence hydrology: Dry. Up nat:rral slope from edge oJwetland
Is the wetland hydrology criterion met? 1Vo Rationale: No evidence of inundation or satteratiorr.
WETLAi�1D DETERMINATION
. Are wetland criteria met? 1�'0 �
• Rationale for wetland decision: No positive in�icarors for mry parameter I
i� : Project Name: Yineyard Courr Property Terra Associates,Inc.
Field Investigator(s): T. R Strong 12525 Willows Road, Suite 101
Project No.: T-�011 Date: 4/15/98 �Kirkland,Washington 98034
I
�
DATA FORM
ROUTINE ONSITE WETLAND DETERMINATION
1987 1989
Describe General Site Forested wetland Data Point No.: 4
Conditions:
- Site Disturbance? Close to driveway,filled area, streets, etc. Location: --IS' W of TA-13
VEGETATION
o y � � �
Dominant Plant Species � � � Dominant Plant Species � � �
� " � � w' b
� � � � �
i Poptrlus trichocarpa FAC T $
2 Fraxinus latifolia FACW T 9
3 Physocar•�r�s caprtatirs FACW S 10 �
4 Symphorrcarpos alb:u NI S 11
5 Spiraea dot�glasii FACW S 12
6 13
7 14
Percent of dominant species that are OBL,FACW, and/or FAC: 80%
, ' Is the hydrophytic vegetation criterion met? Yes Rationale: > SO%F.4C,FACW, or OBL
SOIL
Soil Type: Alderwood grc�velly sandy loam Hydric Soils List: No
I� ; Histic Epipedon? No Mottles? No Gleyed? No
Matrix Color: 10 YR 2/1 Mottle Colors: - Depth: 10"
Other hydric soil indicators:
Is the hydric soil criterion met? Yes Rationale: Low chroma
' i
HYDROLOGY
Is the ground surface inundated? No Surface water depth: -
Is the soil saturated? Y�.s
', Depth to free-standing water in probe hole: �20"
' Other field evidence hydrology: Moist to surface, bare soil, mud cracks, matted leaf debris, topographic basin.
Is the wetland hydrology criterion met? Yes Rationale: Evidence ofrecent irtundarion.
WETLAND DETERNIINATION
Are wetland criteria met? Yes -
. Rationale for wetland decision: Positive indicators for all parameters.
I Project Name: Vineyard Court Properry
Terra Associates, Inc.
Field Investigator(s): T. R Strong 12525 Willo�vs Road, Suite 101
Project No.: T-4011 Date: 4/1.5/98 ,; Kirkland,Washington 98034
,', — _ - ', : . .
.. , _ . . . . . . . . . , :��
DATA FORM
ROUTINE ONSITE WETLAND DETERMINATION
1987 1989
Describe General Site Forested wetland Data Point No.: S
Conditions:
- Site Disturbance? Close to recent clearing Location: �I S' W of TA-�-A
VEGETATION
o ^ � o �, �
Dominant Plant Species � � � �Dominant Plant Species � � �
:� � � '�� �
c v� c �;
1 Populus trichocarpa FAC T $ Carex canescerrs FACN H
2 Frarinus latifolia FACW T 9 Polystichum rnunitum F�CU H
3 R::bus spectabilis FAC _ S 10
4 Rubus discolor FACII S 11
5 Ilex aquifolium F.4CU S 12
6 Spiraea douglasii FACW S 13
7 Carex obmrpra OBL H 14
Percent of dominant species that are OBL,FACW,and/or FAC: 67�
Is the hydrophytic vegetarion criterion met? Yes Rationale: >50%F�C. FACW, or OBL
SOIL
Soil Type: Alderwood gravelly sandy loam Hydric Soils List: No
Histic Epipedon? Y�s Mottles? Traces Gleyed? 1Vo
Mah-ix Color: 10 YR 3/2 Mottle Colors: 10 YR 3/4 Depth: 10"
Other hydric soil indicators: Sarurared ,
Is the hydric soil criterion met? Yes Rationale: Low chroma with motrles '
HYDROLOGY
Is the ground surface inundated? Yes Surface water depth: 2"
Is the soil saturated? Yes
Depth to free-standing water in probe hole: -
Other field evidence hydrology: Brood shallow swale. --6'fromllowing water in streain channel.
Is the wetland hydrology criterion met? Yes Rationale: Inundated and saturcted. �
WETLAND DETERNIINATION '�
Are wetland criteria met? Y�s
Rationale for wetland decision: Positive indicators for all para�neters.
Project Name: Vineyard Court Property Terra Associates,Inc.
Field Investigator(s): T. R Strong 12525 Willows Road,Suite 101
Project No.: T-4011 Date: 2/2.i/99 Kirkland,Washington 9�034
L . _.
. DATA FORM
ROUTINE ONSITE WETLAND DETERMINATION
1987 1989 �
Describe General Site Cleared. Blackberry thickel prior to clearing. Data Point No.: 6
Conditions: ;
- Site Disturbance? Recently cleared Location: —15'E of TA-3-A #
�
VEGETATION
s
� � � � S �= E k
Dominant Plant Species � � � Dominant Plant Species � � r
�. " �
c � v� c� �n
f
1 No vegetation $ �
2 9 �
3 � 10
4 11 �
5 12 •
6 I3
7 14
Percent of dominant species that are OBL, FACW, and/or FAC: -
Is the hydrophytic vegetation criterion met? - Rationale: Undetermined
SOIL
Soil Type: Alderwood gravelly sandy loam Hydric Soils List: No
Hisric Epipedon? No Mottles? No Gleyed? No
Matris Color: 10 YR 3/3 Mottle Colors: - Depth: 10" ',
Other hydric soil indicators: None �
Is the hydric soi]criterion met? No Rationale: High chroma, no mottles. I
HYDROLOGY �
�
Is the ground surface inundated? No Surface water depth: - : 'i
Is the soil saturated? Y�.s
Depth to free-standing water in probe hole: �IO"ar end of wettesr winter on record '
i
Other field evidence hydrology: None. Upslope frorn stream channel. '
Is the wetland hydrology criterion met? No Rationale: No evidence oJlong-term saturation.
WETLAND DETERMINATION
Are wetland criteria met? No
- Rationale for wetland decision: No positrve rndicators jor arry parameter.
Project Name: t'ineyard Court Properry Terra Associates,Inc.
Field Investigator(s): T. R Strong 12525 Willo�vs Road,Suite 101
Project No.: T-4011 Date: 2/25/99 Kirkland,Washin�ton 98034
I ,. . - _ • . .
�� DATA FORM ;
ROUTINE ONSITE WETLAND DETERNIINATION '
- � 19871989 '��
Describe General Site Forested wetland Data Point No.: 7 �
Conditions:
j Site Disturbance? Downstream from detention pond/created wetland Location: —1 S'E of TA-�-B ',
VEGETATION '
� ' '
g � � o � � ��
Dominant Plant Species � � � Dominant Plant Species � � r
� V � �..� � �I
� � � � � � �
1 Acer macrophyllum FACU T $
2 Fraxinus larifolra FAC6Y T 9 � �,
3 Rub:u spectabilis FAC S 10 ' '
4 Cornus stolonifera FAC�V S 11 ',
_ 5 Carex obnupta OBL H 12
' , 6 Polystichum munitum FACU H 13 �
' ' 7 14 � �
_ Percent of dominant species that are OBL,FACW,and/or FAC: 67% i
�
Is the hydrophytic vegetation criterion met? Y�s Rationale: >50%FAC. FACW, or OBL ,
� � i
�
� '� SOIL '
i
Soil Type: Alderwood gravelly sandy loam Hydric Soils List: No i
Histic Epipedon? 3'es Mottles? No Gleyed? No '
' Matrix Color: 10 YR 2/1 Mottle Colors: - Depth: 10" ;
Other hydric soil indicators: Sacurared ',
Is the hydric soil criterion met? Yes Rationale: Low chroma, saturated ,
�IYDROLOGY �
�
� Is the ground surface inundated? No Surface water depth: - I
_ Is the soil saturated? Yes
Depth to free-standing water in probe hole: To surface
Other field evidence hydrology: Broad,shallow s�vale. �20'from stream channe!with�lowing water.
Is the wetland hydrology criterion met? Yes Rationale: Sarurared.
WETLAND DETERMINATION
Are wetland criteria met? Yes
�- Rationale for wetland decision: Positive indicators for all parameters.
Pro}ect Name: Vineyard Court Property Terra Associates,Inc.
- Field Investigator(s): T.R Strong 12525 Willo�vs Road, Suite 101
Project No.: T-4011 Date: 2/25/99 Kirkland,Washington 98034
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DATA FORM
ROUTINE ONSITE WETLAND DETERMINATION
1987 1989 �
Describe General Site 2nd growth mixed forest Data Point No.: 8
Conditions: i
Site Disturbance? Close to street, residential areas. Locarion: —l.i' W of TA--�-B �
VEGETATION
o �„ � o w � :
Dominant Plant Species � � r pominant Plant Species � � �
c � rn � � �n
1 Pseudotsuga men.iesii FACU T $ Rubus ursinus F�iCU V •
;
2 Prunus emarginata FACU T 9 Polystichum munitum FACU H `
3 Acer macrophyllum FACU T 10
4 Rubus discolor FACU S 11 �
5 Rubus spectabilis FAC S 12
6 Demlerra cerasiformis UPL S 13
7 Corylus cornuta FACU S 14
Percent of dominant species that are OBL,FACW,and/or FAC: 11 %
Is the hydrophytic vegetation criterion met? No Rationale: <SO%FAC, FACW, or OBL
SOIL �
. Soil Type: Alderwood gravelly sandy loam Hydric Soils List: No �
Histic Epipedon? No Mottles? No Gleyed? 1�'0
Ma�-ix Color: 10 YR 3/4 Mottle Colors: - De th: 10" ��
P �
Other hydric soil indicators: None ',
Is the hydric soil criterion met? No Rationale: High chroma, no morrles.
HYDROLOGY '�
Is the ground surface inundated? No Surface water depth: -
Is the soil saturated? Yes
' Depth to free-standing water in probe hole: —16"at end of weltest winter on record. �
Other field evidence hydrology: None. Upslope from edge of wetland
' Is the wetland hydrology criterion met? No Rationale: No evidence of inundalion or saturation.
i
WETLAND DETERMINATION
� Are wetland criteria met? No �
-- Rationale for wetland decision: No posirive i„dicarors;for a,ry parameter.
; Project Name: Ytneyard Court Property Tetta Associates,Inc.
�— Field Invesrigator(s): T.R Srrong 12525 Willows Road,Suite 101
Project No.: T-4011 Date: 2/25/99 Kirkland,Washington 98034 :
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DATA FORM
ROUTINE ONSITE WETLAND DETERMINATION
1987 1989
�
Describe General Site Forested wetland Data Point No.: 9
Conditions:
Site Disturbance? Close to recent clearing, south of detention pond/ Location: —10' WNW of T.4-9 A
�
wetland
VEGETATION
o �, � o �, �
Dominant Plant Species � � � Dominant Plant Species � � �
' � � � � �
� rn �� r�
1 Frarinus latifolia FACW T $
2 Acer circinatum FAC S 9
3 Rubus drscolor FACU S 10
4 Carex obnupta OBL H 11
5 Glyceria elata F.4CyV H 12
6 13
7 14
Percent of dominant species that are OBL,FACW,and/or FAC: 80�
Is the hydrophytic vegetation criterion met? Y�s Rationale: > SO%F�iC. FACW, or OBL
SOIL
Soil Type: Alderwood gravelly sandy loam Hydric Soils List: No
Histic Epipedon? Y�.s Mottles? No Gleyed? No
Matrix Color: 10 YR 2/1 Mottle Colors: - Depth: 10"
' _ Other hydric soil indicators: Saturated,high organic content
Is the hydric soil criterion met? 3'es Rationale: Low chroma, high orgQnic contenr
;
� HYDROLOGY
Is the ground surface inundated? Yes Surface water depth: 8"
Is the soil saturated? Yes
Depth to free-standing water in probe hole: -
Other field evidence hydrology: Cenrer offlowrng srream channel.
Is the wetland hydrology criterion met? Ye,s Rationale: Inundared and sarurared.
�
� WETLAND DETERMINATION
Are wetland criteria met? Yes
.-- Rationale for wetland decision: Posirive rndicators for all paramerers.
� ! Project Name: Vineyard Court Property Terra Ass�ciates,Inc.
` Field Investigator(s): T. R Srrong 12525 Willows Road, Suite 101
ProjectNo.: T-4011 Date: 2/25/99 Kirkland,Washington 98034 -
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L �_ _ . . _ . _ � � .
DATA FORM
ROUTINE ONSITE WETLAND DETERMINATION
1987 1989
Describe General Site 2nd growth mixed forest Data Point No.: 10
Condirions:
- Site Disturbance? Close to recently cleared area, close to recent Location: �l S'E of TA-9 A
subdivision
VEGETATION
o _ � o �, �
Dominant Plant Species � � � Dominant Plant Species � � �
—� � :� •- �..
� `�" � .� `� �
1 Tsgua heterophylla FACU T $
2 Thuja plicata FAC T 9
3 Prunus emarginata � FACU T 10 �
4 Acer circrnatum FAC S 11 i
5 Rubus discolor FACU S 12 �
6 Gaultheria shal/on FACU S 13 i �
7 Polystichum munitum FACU 14
Percent of dominant species that are OBL,FACW, and/or FAC: �8%-
Is the hydrophytic vegetation criterion met? 1Vo Rationale: <SO%FAC, FACW, or OBL
SOIL
, Soil Type: Alderwood gravelly sandy loam Hydric Soils List: 1�'0
Histic Epipedon? No Mottles? No Gleyed? No
Matrix Color: 10 YR 3/4 Mottle Colors: - Depth: 10"
Other hydric soil indicators: None
Is the hydric soil criterion met? No Rationale: Hrgh chroma, no monles.
AYDROLOGY
Is the ground surface inundated'? No Surface water depth: -
Is the soil saturated? No
Depth to free-standing water in probe hole: Dry ro> 16"
Other field evidence hydrology: None. Upslope from stream channel.
Is the wetland hydrology criterion met? No Rationale: No evidence of inundarron or saturarion.
WETLAND DETERNIINATION
Are wetland criteria met? No
�- Rationale for wetland decision: No positive rndicators for arry parameter.
l_ Project Name: �ineyard Courr Property Terra Associates,Inc,
Field Investigator(s): T. R Srrong - 12525 WiIlows Road, Suite 101
Project No.: T-4011 Date: L25/99 � Kirkland,Washington 98034
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