HomeMy WebLinkAboutRS_Stormwater_Management_Concepts_R2B_CA_171128_v1ATTACHMENT 10 – HYDRAULIC
SUMMARY
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
This document summarizes the conceptual stormwater planning and design for the purposes of
supporting City of Renton permits for the I-405 Renton to Bellevue Project – Stage 1 Project (Stage 1). This
project will be delivered as one project by WSDOT through design-build contracting.
The scope of this summary is limited to drainage basins that are directly associated with stormwater
management concepts and discharges that fall within the City of Renton.
Project Description
Stage 1 of the I-405 Renton to Bellevue Project extends along I-405 for approximately 8 miles from the
SR 169 interchange (Milepost [MP] 3.8) in Renton to the I-90 interchange (MP 11.9) in Bellevue. These
Stage 1 improvements propose the following improvements:
• Northbound and Southbound I-405 (MP 3.8 – MP 11.9): Widen I-405 from SR 169 to just north of
I-90 to accommodate an additional lane both northbound and southbound. The additional lane
will be coupled with the existing northbound and southbound HOV lane to create two express toll
lanes (ETLs). Where feasible, the additional lanes will be developed by restriping instead of
roadway expansion.
• Sunset Boulevard N (MP 4.53) and NE Park Drive (MP 5.42) Interchanges: Widen the I-405
overpasses at these two interchanges.
• NE 30th Street (MP 6.52): Replace the local road overpass abutment slopes with retaining walls
to accommodate I-405 widening. Lower the southbound I-405 roadway.
• May Creek Bridges (MP 7.18): Reconstruct the northbound and southbound I-405 bridge
structures over May Creek.
• NE 44th Street Interchange (MP 7.48): Reconstruct the local road overpass at the interchange.
Construct new direct access ramps for transit and ETL users in the I-405 median. Reconstruct Lake
Washington Boulevard NE between NE 44th Street and SE 76th Street, and realign the
northbound on-ramp to I-405 to connect to Lake Washington Boulevard NE.
• Lake Washington Trail (MP 7.35 – MP 10.25): Realign and reconstruct the existing trail west of its
current location to reside within the Eastside Rail Corridor from Ripley Lane in Renton to Coal
Creek Parkway in Bellevue.
• Noise Walls: Construct up to three new walls and relocate two existing noise walls.
• Stormwater: Construct stormwater runoff treatment, flow control facilities, and conveyance
systems.
• Fish Passage: Construct new fish passage crossings to eliminate existing fish barriers in the vicinity
of the NE 44th Street interchange.
• Various improvements within Bellevue
• Construct minor improvements, including pavement markings, permanent signing, illumination,
intelligent transportation systems and ramp metering, barriers, and tolling gantries.
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
Note that the final design will continue to develop these stormwater management concepts. The design-
build contract will specify performance standards based on the Washington State Department of
Transportation (WSDOT) Highway Runoff Manual requirements. This design is one solution that will meet
that standard, but this information is subject to change during final design, using equivalent mitigation
measures.
Project Watershed
The project is located in the lower elevations of Water Resource Inventory Area 8 – Lake Washington
Watershed. The contributing basins have undergone extensive land use changes in the form of
commercial, urban, and residential development.
Project Drainage Basins
The work falls within the City of Renton and the City of Bellevue and includes numerous tributaries to Lake
Washington, including Cedar River, Johns Creek, Clover Creek, May Creek, and unnamed tributary
UNT 08.LW.0283 (formerly called Gypsy Creek).
The project evaluation includes numerous Threshold Discharge Areas (TDAs) which represent individual
highway drainage areas that outlet to a single natural discharge location or multiple natural discharge
locations that combine within ¼ mile downstream (as determined by the shortest flow path).
See Attachment 1 for a vicinity map, and Attachment 2 for an illustration of the TDA boundaries. Only
those TDAs that fall within the City of Renton are discussed in detail within this stormwater management
concept summary.
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
Table 1: Water Resource Inventory Area 8 – Lake Washington
Threshold
Discharge
Area
Receiving Water Body
Sub-Basin Limits Along I-405,
Unless Otherwise Noted
Mile Post (MP)
C1 Cedar River via WSDOT discharge MP 4.00 to MP 4.48
J0 Johns Creek via Renton Valley MP 4.48 to MP 4.50
J1 Johns Creek via N 8th Street MP 4.50 to MP 4.60
J2 Johns Creek via Houser Way MP 4.60 to MP 4.72
J3 Johns Creek via SR 900 drainage MP 4.72 to MP 5.87
CL1 Clover Creek via I-405 discharge MP 6.07 to MP 6.26
M1 May Creek via I-405 discharge MP 6.75 to MP 7.16
M2 May Creek via Lake Washington Blvd. N. Along Lake Washington Blvd. N from
May Creek to Seahawks Way
W1-1 Lake Washington via private drainage MP 5.87 to MP 6.09
W1-2 Lake Washington via UNT 08.LW.0283
(Seahawks Way and VMAC drainage systems)
MP 6.07 to MP 8.85
W1-3 Lake Washington via private drainage MP 7.73 to MP 7.97
W1-4 Lake Washington via private drainage MP 7.97 to MP 8.19
W1-5 Lake Washington via private drainage MP 8.19 to MP 8.49
W1-6 Lake Washington via private drainage MP 8.49 to MP 8.79
Note: Refer to Attachment 3 for an illustration of the Proposed Condition TDAs
Proposal Overview
The Stage 1 stormwater concepts generally follow those that were developed to support the I-405, SR 169
to I-90 - Renton to Bellevue Project Environmental Assessment. The stormwater mitigation measures
continue along similar concepts that were presented in the 2006 EA, so water resources are similarly
protected. The reduced footprint of Stage 1 and continued development has resulted in changes to the
proposed stormwater improvements. The most notable differences are as follows:
• TDAs were established based on more detailed mapping and experience along the corridor, so
there is more detail on individual discharges to Lake Washington.
• NE 3rd Street is significantly reduced, which results in less impervious area, no new Cedar River
discharge, and no runoff retrofit in the Cedar River basin.
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
The Stage 1 project widening will also increase the pollutant generating impervious surface area (PGIS) by
45.56 acres within the Stage 1 project limits (including work outside the City of Renton). Overall, PGIS will
increase by approximately 23 percent over current conditions. Table 2 represents the changes specific to
work that influence discharges within the City of Renton. The project will include the following stormwater
facilities:
• Existing stormwater collection and conveyance systems will be modified as required for the new
roadway geometry and as required for stormwater management using equivalent catchment
areas.
• Two new flow control and many new runoff treatment facilities will be constructed to mitigate
new PGIS as well as to provide additional retrofit runoff treatment for untreated WSDOT PGIS.
• One spill containment pond will be replaced in kind.
• Five existing fish barriers will be mitigated by four new fish passible structures.
• One new conveyance system will be constructed under Lake Washington Boulevard to discharge
into Johns Creek.
• Existing runoff treatment and flow control facilities will be modified or replaced with measures
complying with the current WSDOT Highway Runoff Manual where the roadway widening impacts
existing facilities.
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
Table 2. Summary of Stormwater TDAs Associated with Discharges within Renton
Receiving
Waterbody TDA
Existing
PGIS in
TDA
(acres)
Existing
Treatment
(acres)
Proposed
PGIS in
TDA
(acres)
Proposed
Treated
PGIS
Post
Project
(acres)
Cedar River C1 30.34 2.29 30.65 11.79
Johns Creek
JO 0.85 0.00 0.87 0.00
J1 4.84 0.00 1.90 0.00
J2 5.44 0.00 31.90 31.90
J3 5.73 0.00 0.00 0.00
J4 10.81 0.00 0.00 0.00
W1-1
Private Drn to Lake
Wa.
3.07 0.00 0.48 0.00
UNT 08.LW.0283
CL1
Clover Creek 2.84 0.00 0.001 0.00
M1
May Creek at I-405 12.79 0.00 0.001 0.00
M2
May Creek at Lake
Wa. Blvd.
8.70 3.41 6.58 5.60
W1-2
UNT.08.LW.0283 11.34 0.00 60.37 58.50
W1-3
Private Drn to Lake
Wa.
1.62 0.00 0.001 0.00
W1-4
Private Drn to Lake
Wa.
1.71 0.00 0.00 0.00
W1-5
Private Drn to Lake
Wa.
2.86 0.00 0.00 0.00
W1-6 Private Drn to
Lake Wa. 1.48 0.00 0.00 0.00
Totals 104.42 5.7 132.75 107.79
Notes:
1. WSDOT highway runoff will be diverted to J2 for runoff treatment following the design concepts that
were presented in the 2006 BA
2. All highway runoff flows will be diverted from Clover Creek and May Creek TDAs into TDA W1-2
(formerly called Gypsy Creek) following the design concepts that were presented in the 2006 BA
3. WSDOT highway runoff will be diverted to W1-2 for runoff treatment following the design concepts that
were presented in the 2006 BA
See Attachment 2 for an illustration of the TDA boundaries
See Attachment 3 for an illustration of the conceptual flow control and runoff treatment facilities.
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
Flow Control
Infiltration is the preferred flow control best management practice (BMP), but there are no known
opportunities for infiltration along the project area. The conceptual design assumes that flow control will
be provided by combined stormwater treatment/detention ponds or detention vaults. Other options may
be considered as the design continues.
A review of the existing flow control facilities along the I-405 corridor was included in the conceptual
design. The following is a summary of the current status of each existing facility.
• TDA J2: Existing detention pond located on east side of I-405 at MP 5.34 to remain.
• TDA W1-2: Existing detention pond (privately owned within the project impact limits) located on
east side of I-405 at MP 7.62 to be removed. At the end of the project, downstream conveyance
will have sufficient capacity. WSDOT is currently working with the City of Renton to assure that
the replacement meets their design requirements.
The following summary conceptual engineering approach for flow control. In many of the TDAs, the new
impervious area has been addressed through flow diversion to discharge into a flow control exempt water
body. Refer to Figure 1 for a graphic representation of highway runoff flow diversions in the concept:
• TDA C1: Direct discharges to the Cedar River are flow control exempt. Flow control will be
considered if the conveyance system capacity is not sufficient for post-project condition.
• TDAs J0 and J2: Change is so small that flow control is not triggered.
• The project conveys WSDOT highway runoff from TDAs J1, J2, J3, J4, and of W1-1 to Johns Creek.
• The project conveys WSDOT highway runoff from TDAs CL1, M1, M2, W1-2, W1-3, W1-4, W1-5,
and W1-6 to the UNT 08.LW.0283 conveyance to Lake Washington. The conveyance systems
downstream of the I-405 crossings were constructed to provide conveyance capacity to Lake
Washington for the full development in the basin as well as the future I-405 widening. The project
removes existing capacity constraints at the I-405 crossing. This discharge is therefore assumed
to be flow control exempt.
• The project maintains WSDOT highway runoff to W2-1 Pleasure Point, and W2-2 Lakehurst Creek,
while diverting any new additional WSDOT highway runoff to the W2-3 Bagley Lane direct
discharge to Lake Washington. The increase in runoff to TDA W2-3 is flow control exempt as a
direct discharge to Lake Washington
• The project reduces WSDOT highway runoff to W3-1 Newcastle Beach Park and W3-2 Coal Creek,
while diverting any new additional WSDOT highway runoff to the W4 direct discharge to the
Mercer Slough wetland complex. Being directly associated with Lake Washington, the wetland
discharge is flow control exempt.
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
Figure 1. Summary of Threshold Discharge Areas, Outfalls, and Receiving Water Bodies.
Basin Threshold Discharge
Areas
Outfall Receiving Water
Body
Listed Fish
C1 Cedar River
Cedar River
J0 Combine with City
Renton Drainage
J1 Johns Creek
Johns Creek
J2
New discharge
J3 Johns Creek
J4
W1-1
May Creek
CL1
M1
M2
Gypsy W1-2 UNT 08.LW.0283
Subbasin W1-3
W1-4
W1-5
W1-6
Legend:
TDAs flows are split in the proposed concept
All of the TDA runoff is routed to one discharge in the proposed concept
The conceptual engineering approach includes flow control to mitigate the effective new impervious area
within the Cedar River which is flow control exempt. To avoid in-water and shoreline work associated
with the Cedar River, flow control is proposed to mitigate flow increases that would result from the
proposed 0.31 acres of new impervious surface in the basin. The conceptual design includes a 0.17 acre-
foot detention vault that would match existing peak flow rates. Final design will verify downstream
capacities to evaluate the level of flow control needed. This detention facility would fall with the City of
Renton Cedar Valley Aquifer Groundwater Protection Zones 1 and will be designed in accordance with
Renton Municipal Code 4-3-050 Critical Areas Regulation. A concrete liner is anticipated, and WSDOT is
working through the details of gaining approval for them to be open top to facilitate maintenance.
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
Runoff Treatment
The WSDOT Highway Runoff Manual provides a variety of enhanced runoff treatment BMPs that focus on
removal of sediment and metals. The conceptual design proposes to install media filter drain (MFD) and
compost-amended biofiltration swales (CABS) runoff treatment BMPs.
The conceptual design included a review of the existing water quality facilities along the I-405 corridor.
• TDA C1: Existing spill containment pond located on west side of I-405 at MP 3.95 will remain.
• TDA C1: Existing media filter drain type 4 BMP located on west side of I-405 at MP 3.90 will remain.
• TDA M2: Existing Lake Washington Blvd. N bioretention cell located just north of bridge over May
Creek will remain.
• TDA W1-2: Existing Constructed Stormwater Treatment Wetland located on west side of I-405 at
MP 7.46 to be removed.
• TDA W1-2: Existing flood storage pond located on east side of I-405 at MP 7.50 to be removed.
Numerous water quality treatment facilities are being proposed. Table 3 summarizes the additional new
runoff treatment that is proposed within the City of Renton. Final design requirements will follow a
performance specification based on a minimum enhanced runoff treatment requirement. The new runoff
treatment, plus the existing runoff treatment to remain, will result in 116.7 acres of WSDOT runoff treated
within the TDAs that discharge within the City of Renton limits. Runoff treatment facilities mitigate the
new PGIS plus retrofit a portion of the existing untreated runoff.
Conveyance
The projects will replace many structures within the project limits in areas of pavement widening. Closed
conveyance systems will be used as the preferred conveyance method along the I-405 corridor due to the
site constraints.
Roadway widening will require new collection structures along the new edge of pavement. These new
structures will connect to the existing drainage systems. Existing conveyance will be modified as required
to satisfy water quality treatment and flow control measures. The conceptual design has only considered
conveyance as it relates to the feasibility of establishing collection areas for runoff treatment and flow
control. Detailed conveyance plans will be produced during the final design.
Widening along Lake Washington Boulevard on the side west of I-405 and realignment of Lake Washington
Boulevard on the east side of I-405 will require reconstruction of a portion of the City of Renton storm
drainage systems. These improvements are the subject of conceptual designs that will be documented in
a Stage 1 Storm Drainage Technical Information Report (TIR). This TIR is being coordinated separately and
will be submitted and reviewed by the City of Renton to set the scope of this work prior to WSDOT
contracting for final design though Design-Build procurement.
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
Table 3: Summary of New Runoff Treatment Proposed in Conceptual Design
Basin
Name Facility I.D. I-405 Milepost
Unless Noted
PGIS
Catchment
Area (ac)
Facility Type
Facility
Length Req’d
(ft.)
C1 CABS C2.1 4.05 (RT) 9.50 CABS 165
J2 CABS J2.1 5.18 (LT) 10.86 CABS 267
J2 CABS J2.2 5.25 (LT) 4.30 CABS 261
J2 CABS J2.3 5.30 (LT) 1.68 CABS 231
J2 CABS J2.4 5.41 (LT) 15.06 CABS 217
M2 CABS M2.14 7.30 (LT) 2.19 CABS 200
W1-2 CABS W1.2.1 7.37 (RT) 29.69 CABS 168
W1-2 CABS W1.2.2 7.46 (LT/RT) 28.81 CABS 168
W1-2 CABS W1.2.3 L. Wa. Blvd. NE to
NB On-ramp 0.55 CABS 107
Water Quality Totals within Renton 102.64
Notes:
1. Quantity presented in acre-feet for pre-settling cell storage volume. The existing constructed wetland cell is
sufficiently sized for the proposed condition.
2. Definitions: CABS = Compost Amended Biofiltration Swale, MFD = Media Filter Drain Type 1 or 2,
(LT) = facility is on the left at that mile post, and (RT) = facility is on the right at that mile post.
3. Runoff BMPs are subject to change as the design continues.
4. Part of the conceptual Park & Ride layout to be permitted and constructed by others.
Fish Barriers
The Stage l Project includes known fish barriers within the project limits. There are seven culverts currently
on the Washington State Department of Fish and Wildlife (WDFW) fish barrier list:
• Johns Creek at MP 5.09 is listed due to steep grade.
• Clover Creek at MP 6.31 is listed due to water surface elevation drop.
• Unnamed tributary UNT 08.LW.0283 at MP 7.61 has two I-405 crossings listed due to steep grade.
• Unnamed culvert at MP 7.7A is listed due to slope.
• Unnamed culvert at MP 7.8 is listed due to slope.
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
Figure 2: Vicinity Map Showing Culverts in the City of Renton
The culvert crossings at UNT 08.LW.0283, 7.7A, and 7.8 will be upgraded to fish passable structures as
part of Stage 1. All other fish barriers will be addressed by future I-405 improvement projects.
Unnamed Culvert at MP 7.8
Unnamed Culvert at MP 7.7A
Unnamed Trib. 08.LW.0283
Clover Creek
Johns Creek
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
ATTACHMENT 1
Stage 1 Project Vicinity Streams
SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
ATTACHMENT 2
Threshold Discharge Area Layout
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PLAN REF NO
PROPOSED POST-PROJECT TDA BOUNDARIES
RENTON TO BELLEVUE
I-405
CORRIDOR WIDENING & EXPRESS TOLL LANES
FILE NAME c:\users\dingx\pw_wsdot\d0140551\XL4653_PS_DR_800_TDA_01.dgn
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TDA J2
Johns Creek
TDA J1
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TDA J0
SCALE IN FEET
0 400 800
LAKE WASHINGTON EDGE
LAKE WASHINGTON
EASTSIDE RAIL CORRIDOR
Lake Washington
TDA W1-1
Lake Washington
TDA W1-2
Clover Creek
TDA CL1
I-405 MP 4.0
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SUMMARY OF STORMWATER MANAGEMENT CONCEPTS
I-405 RENTON TO BELLEVUE PROJECT - STAGE 1
ATTACHMENT 3
Flow Control and Runoff Treatment Drawings
T
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Department of Transportation
PLAN REF NO
PROPOSED POST-PROJECT TDA BOUNDARIES
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I-405
CORRIDOR WIDENING & EXPRESS TOLL LANES
FILE NAME c:\users\taylorsu\pw_wsdot\d0140551\XL4653_PS_DR_800_BA_TDA_Exhibit_02.dgn
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STREAM 7.7A
MAY CREEK
STREAM 8.7
LAKEHURST CREEK
STREAM 8.15
May Creek
TDA M1
May Creek
TDA M-2
Lake Washington
TDA W1-3
Lake Washington
TDA W1-4 Lake Washington
TDA W1-5
Lakehurst LW
TDA W2-2
Lake Washington
TDA W1-6
112TH AVE SE VICINITYGYPSY SUBBASIN
2
LAKE WASHINGTON
UNT 08.LW.0283
PROPOSED TDA W1-2
TDA M1 COMBINES INTO
EXISTING MAINLINE PGIS OF
INTO PROPOSED TDA W1-2
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LAKE WASHINGTON EDGE
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I-405
RENTON TO BELLEVUE
CORRIDOR WIDENING & EXPRESS TOLL LANES
SHEET 1
AREA = 50.0 AC
TDA - C1- CEDAR RIVER
POND TO REMAIN
EXISTING SPILL CONTAINMENT
SEE SHEET 2
DETENTION VAULT C2.1
CATCHMENT AREA = 8.55 ACRE PGIS
DIMENSIONS = 2-165'(L) X 11'(W); 4:1 (SIDE SLOPE)
BIOSWALE - CABS C2.1
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SHEET
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Washington State
Department of Transportation
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LEGEND
POST IMPERVIOUS AREA
IMPERVIOUS AREA TO BE REMOVED
NEW IMPERVIOUS AREA
DATUM
(NAVD) 88
100 200
SCALE IN FEET
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U
U
U
U U
U
UU U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
UU
U
U
U
U
U
U
U
U
U
U
U
U
UU
UU
UU
U
U
U
U
U
UU
U
U
U
U
U
U
UU
U
UU
U
U
U
U
C
C
C
C
C
C
C
C
C
C C
C
C
C
C
C
C
C
C
C
C
C
C
C C
C
C
C
CC
CC
C
C
U
CV
P
B
U
U
U
U
U
U
U
U U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
G
G
G
GG
G
G
G
G
MP 4.10 MP 4.15 MP 4.20
MP 4.25
MP 4.30
MP 4.35
MP 4.40
MP 4.45
MP 4.50
MP 4.55
MP 4.60101.26CB Type 2 48" dia
18" Pcssp98.00
SHEET
OF
SHEETS
.
Washington State
Department of Transportation
-
LEGEND
POST IMPERVIOUS AREA
IMPERVIOUS AREA TO BE REMOVED
NEW IMPERVIOUS AREA
DATUM
(NAVD) 88
100 200
SCALE IN FEET
0
G
R
A
N
D
E
Y
B
R
O
NS
O
N
W
A
Y
SUNSET BLVD NE
M
A
T
C
H
T
O
S
H
E
E
T 3
M
A
T
C
H
T
O
S
H
E
E
T
1
T.23N. R.5E. W.M.
APARTMENTSMONTEREY
HEALTHGROUP
SB I-405
NB I-405
N. 3
R
D
S
T
HOUSER WAY
SUNSET BLVD
VERMONT PL
N. 4T
H S
T
2
19
I-405
RENTON TO BELLEVUE
CORRIDOR WIDENING & EXPRESS TOLL LANES
SHEET 2
AREA = 58.90 AC
TDA - J2- JOHNS CREEK
AREA = 4.59 AC
TDA - J1- JOHNS CREEK
AREA = 1.18 AC
TDA - J0- JOHNS CREEK
AREA = 1.18 AC
TDA - J0- JOHNS CREEK AREA = 4.59 AC
TDA - J1- JOHNS CREEK
CATCHMENT AREA = 8.55 ACRE
NET NEW IMPERVIOUS = 0.31 ACRE
REQ'D VOLUME = 0.17 AC-FT
DIMENSIONS = 110'(L) X 17'(W) X 5'(D)
DETENTION VAULT C2.1
S
T
T
T
R R
RR
T
T
T
R
R
M
B
M
B
MB
MB
M
B
MB
M
B
M
B
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
CC
CC
C
C
CC
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
CV
CV
U
U
UU
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
UU
UU
UU
U
U
U
G
G
G
G
G
G
G
G
M
P
4
.6
5
MP 4.70 MP 4.75 MP 4.80 MP 4.85 MP 4.90 MP 4.95 MP 5.00 MP 5.05 MP 5.10
MP 5.15
79.7080.20
96" cl.iv rcssp
18" pcssp
80.1791.54CB type 72" dia
18" pcssp80.17
18" pcssp
79.98
MH type 1 48" diam
91.23
99.97CB Type 2 48" dia
18" Pcssp
95.00
12" Pcssp
CB Type 1
95.44
96.26 12" Pcssp
95.44CB Type 112" Pcssp
94.8512" Pcssp
98.53CB Type 1
12" Pcssp
94.85
94.4612" Pcssp
98.15CB Type 1
12" Pcssp
94.46
12" Pcssp
94.04 97.52CB Type 1
12" Pcssp
94.04
12" Pcssp94.04
96.80CB Type 1
12" Pcssp92.78
12" Pcssp91.48
95.34CB Type 1
12" Pcssp
91.48
12" Pcssp90.28
94.37CB Type 1
12" Pcssp90.28
12" Pcssp88.94 93.03CB Type 1
12" Pcssp88.94
12" Pcssp
87.88 91.97CB Type 1
12" Pcssp
87.88
36" Rcssp79.64
79.1136" Rcssp79.6196" CL IV.R.C.S.S.P
90.45MH TYPE 4-48" Diam
90.20 90.15MH TYPE 4-48" Diam
90.10
89.9790.73CB Type 2 72 in diam12" Pcssp
GI TYPE 2 MOD
GI TYPE 2 MOD
GI TYPE 2 MOD
78.1936" Rcssp
78.69
89.94END DETENTION TANK
96" CL IV R.C.S.S.P.
89.89CB TYPE 2 72 IN DIAM
36" Rcssp78.66 18" Pcssp78.66
18" Pcssp
78.33 90.98MH TYPE 3 72 IN DIAM
18" Pcssp
78.66
69.3236" Sc
36" Sc69.32
70.80
CB Type 2 72 in diam36" Rcssp
70.80
36" Rcssp71.00
76.5CB Type 2 w/degris cage 72" dia
81.0
36" Sc
MH Type 3 72 in diam 67.8036" Rcssp
91.80
12" Pcssp78.72
89.83CB TYPE 2 72 IN DIAM
36" Rcssp79.04
86.85
89.99Concrete Inlet
78.5736" Rcssp
79.07
89.83
96" CL IV R.C.S.S.P.
Begin Detention Tanklet
90.10GI Type 2 mod86.85
90.16 90.22GI Type 2 Mod
MH Type 4 48" Diam
80.03 90.77CB TYPE 2 72 IN DIAM
12" Pcssp86.68
90.71End Detention Tank
36" Rcssp
79.9196" CL IV R.C.S.S.P.
79.41
36" Rcssp
91.3012" Pcssp87.21
89.95
83.90
12" pcssp
84.40
12" pcssp
85.90
12" Pcssp79.98
18" Pcssp
91.61Begin Detention Tank
24" sc
24" sc77.58
C.B type 2 48" diam
C.B. type 2 48" diam/w Debris cage
89.9
MH type 1 48" diam
92.30
24" sc68.40
77.5824" sc
68.4018" Al. sssp
18" Al. sssp
33.63
CB type2 72" diam
38.50
18" pcssp
84.90
EL 99.63 IE 96.04
CB TYPE 1
GI Type 2 Mod
90.22
36.81
6" PVC34.72
6" CONC34.42
CB type2
18" Al. sssp
32.18
36.82
CB type1 36.91
6" PVC35.73
SHEET
OF
SHEETS
.
Washington State
Department of Transportation
-
LEGEND
POST IMPERVIOUS AREA
IMPERVIOUS AREA TO BE REMOVED
NEW IMPERVIOUS AREA
DATUM
(NAVD) 88
100 200
SCALE IN FEET
0
M A T C
H
T O
S
H
E
E
T
2
M
A
T
C
H
T
O
S
H
E
E
T
4
T.23N. R.5E. W.M.
N . 8
T H S
T
N . 8
T H S
T
HOUSER WAY
SB I-405
NB I-405
B
U
I
L
D
I
N
G
S
P
A
C
C
A
R
3
19
I-405
RENTON TO BELLEVUE
CORRIDOR WIDENING & EXPRESS TOLL LANES
SHEET 3
AREA = 4.59 AC
TDA - J1- JOHNS CREEK
AREA = 58.90 AC
TDA - J2- JOHNS CREEK
T
T
T
T
S
T
T
S
T
T
T
T
T
T
U
U
U
U
U
R
R
U
C
C
C
C
C
C
R R
R
R
R
R
R R
U
U
R R
U
C C
C
C
U
C
C
C
C
C
C
C
C
U
U
U
U
U
U
C
U
U
U
U
C
C
C
C
U
U
U
U
U
U
C C
CC
U
U
U
U
U
MB
MB
M
B
C
M
B
M
B
M
B
M
B
M
B
U
U
M B
M
B
M
B
M
B
M
B
M
B
M
B
M
B
U
U
U
U
U
U
U
U
U
U
U
C
C
C
C
C
C
C
C
C
C
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
T
P
S
S
S
S
D6/44
U
U
U
U
U
U
U U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
UU
U
U
U
U
U
U
U
U
GG
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G G
G
G
G
MP 5.15 MP 5.20 MP 5.25 MP 5.30 MP 5.35 MP 5.40 MP 5.45 MP 5.50 MP 5.55
MP 5.60
MP 5.65
TRANSMISSION LINE
115 KV
143.67139.67 CB Type1
12" Pcssp
132.27 136.01 12" Pcssp132.27CB Type 1
12" Di Pipe123.43 128.12CB Type 1
132.4312" Di Pipe
12" Pcssp
12" Pcssp113.44
116.96CB Type 1
12" Pcssp
113.44
12" Pcssp112.98
115.60CB Type 1
12" Pcssp
112.98
115.24
12" Pcssp107.00
12" Pcssp
111.7
0
CB Type 2 48" Diam
12" Pcssp
106.00
12" Pcssp
99.10 102.59CB Type 118" Pcssp97.58 101.25CB Type 1
12" Pcssp
97.58
12" Pcssp
97.75
101.45CB Type 1
102.45
18" Pcssp
97.02
12" Pcssp97.95
12" Dia.slot Drain
12" Dia.slot Drain
C.I
18" Pcssp
93.78
100.28CB Type 2 48" diam
95.67
102.17CB Type 2 48" diam
10012" diam. slot drain
103.54
12" diam. slot drain
101
Conc. Inlet
24" SC
24" SC
18" Pcssp89.59
95.05 18" Pcssp
89.59CB Type 1
35" rcssp
80.71
93.44 18" Pcssp88.65CB Type 2 72" dia92.77
80.18
35" rcssp80.68
96" cl.iv rcssp
96" cl.iv rcssp
93.33
MH-TA 48"diam
E
XI
S
T.
1
8
"
C
M
P
36 "C M P
1
8
"
C
M
P
1 8
"C C P
MH-T3
12" PCSSP
95.30C.B type 2 48" diam
18" pcssp
90.19
18" pcssp90.19
18" pcssp
95.50 C.B type 2
99.0
D6/37
D6/44
110.13Tank outlet
CB Type 2 72" Diam
36" Rcssp
97.97
97.95
98.22
110.67Begin Detention Tank
96" CL IV. RCSSP
110.42MH Type 4- 48" Diam
110.14
98.0096" CL IV. RCSSP
97.50
End Detention Tank
36" RCSSP
12" Pcssp
97.97
12" Pcssp
97.01
12" Pcssp97.88CB Type 2 72" Diam
98.08CB Type2 48"
12" Pcssp
CB Type 1
12" Pcssp
12" Pcssp
95.78
12" Pcssp
95.78
100.94
100.47
Begin Coalesing Plates
End Coalesing Plates
100.56MH Type 3 - 48" Diam
12" Pcssp95.60
12" Pcssp95.60
100.50Grate Inlet
12" Pcssp
98.00
D6/46
D7/7
D7/14
D7/9
D7/17
D7/24
D7/53
D6/47
D7/8
115.24CB Type 2 48" Diam 111.7012" Pcssp
107.0012" Pcssp
CB Type 1
GI TYPE 2
CB Type 1
CB Type 1 W / Solid Metal Cover
MH TYPE 3
MH TYPE 3
CB Type 2
MH Type 3 48"
CB Type 2
140.00
18" Pcssp
133.93
MH TYPE 2 72" DIAM
146.15
18" Pcssp141.70
18" Pcssp
141.70
36" Pcssp
126.70126.0836" Pcssp
126.50
18" Pcssp
152.20
156.15CB TYPE 2 48" DIAM
18" Pcssp
12" Pcssp
12" Pcssp
152.36
152.50
152.20
172.00MH TYPE 1 48" DIAM
18" Pcssp
159.90
164.01CB TYPE 2 48" DIAM
18" Pcssp
159.90
18" Pcssp169.50
174.45CB TYPE 2 48" DIAM
12" Pcssp169.50
CB TYPE 2 48" DIAM.
12" Pcssp
177.75 12" Pcssp177.75
CB TYPE 1
141.7018" Pcssp
158.38CB TYPE 2 48" DIAM.
D7/15
D7/20
D7/23
D7/27
152.26
PCSSP @ 1.5%
18"
E
XI
S
T.
SHEET
OF
SHEETS
.
Washington State
Department of Transportation
-
LEGEND
POST IMPERVIOUS AREA
IMPERVIOUS AREA TO BE REMOVED
NEW IMPERVIOUS AREA
DATUM
(NAVD) 88
100 200
SCALE IN FEET
0
M
A
T
C
H
T
O
S
H
E
E
T
3
N
E
1
4
T
H
S
T
JONES
AVE
NE
900/PARK DR. N
M
A
T
C
H
T
O
S
H
E
E
T
5
T.23N. R.5E. W.M.
4
19
I-405
RENTON TO BELLEVUE
CORRIDOR WIDENING & EXPRESS TOLL LANES
SHEET 4
EXISTING DETENTION POND
AREA = 58.90 AC
TDA - J2- JOHNS CREEK
AREA = 58.90 AC
TDA - J2- JOHNS CREEK
CATCHMENT AREA = 10.86 ACRE PGIS
DIMENSIONS = 2-267'(L) X 8.5'(W); 4:1 (SIDE SLOPE)
BIOSWALE - CABS J2.1
CATCHMENT AREA = 4.30 ACRE PGIS
DIMENSIONS = 261'(L) X 6.5'(W); 4:1 (SIDE SLOPE)
BIOSWALE - CABS J2.2
CATCHMENT AREA = 1.68 ACRE PGIS
DIMENSIONS = 231'(L) X 2'(W); 4:1 (SIDE SLOPE)
BIOSWALE - CABS J2.3
CATCHMENT AREA = 11.93 ACRE PGIS
DIMENSIONS = 217'(L) X 11'(W); 4:1 (SIDE SLOPE)
BIOSWALE - CABS J2.4
U
U
U
M
B
M
B
M
B
M
B
M
B
M
B
M
B
M
B
U
M
B
U
MB
U
T
C
M B
S
T
T
C
C
U
U
U
C
C
C
U
U
U
U
U
U
U
M
B
M
B
U
U
U
U
M
B
M
B
M
B
M
B
U
U
U
U
M
B
M
B
M
B
M
B
M
B
M
B
M
B
U
M
B
M
B
M
B
M
B
M BMB
U
M
B
M
B
M B
M B MB
U
U
U
U
U
U
U
U
U
U
U
U
M
B
M
B
MB
M B
MB
MB
C
C
U
U
U
M
B
M
B
M
B
M
B
M
B
T
C
M
B
U
U
U
U
M
B
M
B
M
B
M
B
M
B
M
B
M
B
U
U
U
U
U U
U
U
U
U
U
U
U
U
U
U
U
U
U
U U
U
UU
U
U
U
U
UU
U
G
G
MP 5.70 MP 5.75 MP 5.80 MP 5.85 MP 5.90 MP 5.95 MP 6.00 MP 6.05 MP 6.10 MP 6.15 MP 6.20 MP 6.25
D7/30 D7/43
D7/42
D7/33
D8/1
D7/41
D8/13
12" Pcssp
186.01
185.03
12" Pcssp
185.90CB TYPE 1
12" Pcssp
192.39
195.89CB TYPE 1
12" Pcssp
191.89
202.38
12" Pcssp
206.38CB TYPE 1
12" Pcssp
202.38
196.00
12" Pcssp179.82
12" Pcssp179.89
MH TYPE 1 48" DIA
195.89CB TYPE 1
12" Pcssp
192.39
12" Pcssp192.39
12" Pcssp
191.89
D7/31
D7/34
D7/38
D8/16D8/15D8/2
SHEET
OF
SHEETS
.
Washington State
Department of Transportation
-
LEGEND
POST IMPERVIOUS AREA
IMPERVIOUS AREA TO BE REMOVED
NEW IMPERVIOUS AREA
DATUM
(NAVD) 88
100 200
SCALE IN FEET
0
N
2
6
T
H
S
T
CLOVER CREEK
T.23N. R.5E. W.M.
JONES AVE NE
SB 1-405
NB 1-405
HIGH AVE NE
N
2
4
T
H
S
T
M
A
T
C
H
T
O
S
H
E
E
T
4
M
A
T
C
H
T
O
S
H
E
E
T
6
5
19
I-405
RENTON TO BELLEVUE
CORRIDOR WIDENING & EXPRESS TOLL LANES
SHEET 5
AREA = 58.90 AC
TDA - J2- JOHNS CREEK
AREA = 4.69 AC
TDA - W1-1 - LAKE WASHINGTON
AREA = 86.97 AC
TDA - W1-2 - LAKE WASHINGTON
AREA = 2.03 AC
TDA - CL1 - CLOVER CREEK
AREA = 2.03 AC
TDA - CL1 - CLOVER CREEK
AREA = 58.90 AC
TDA - J2 - JOHNS CREEK
AREA = 4.69 AC
TDA - W1-1 - LAKE WASHINGTON
C
C
M
B
M
B
M
B
M
B
M
B
C
C
U
U
M BMB
M
B
M
B
C
M
B
M
B
M
B
U
U
U
U
M
B
M
B
M
B
M
B
U
U
U
U
U
U
U
U
U
U
U
M
B
M
B
M
B
M
B
M
B
M
B
M
B
M
B
M
B
M
B
C
C
U
U
U
MB
U
MB
MB
U
U
U
U
U
U
C
C
C
C
C
C
U
U
U
U
U
M
B
M
B
M
B
M
B
M
B
M
B
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
CC
C
C
C
CC
C
C
C
C
C
C
B
U
S
B
U
S
B
U
S
O
N
L
Y
O
N
L
Y
O
N
L
Y
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
G G
G
G
G
G
G
G
G
G
G
MP 6.25 MP 6.30 MP 6.35 MP 6.40 MP 6.45 MP 6.50
MP 6.55
MP 6.60
MP 6.65
MP 6.70
MP 6.75TYPE 2 48" DIA
TYPE 2 48" DIA
TYPE 2 48" DIA
TYPE 2 48" DIA
TYPE 2 48" DIA
TYPE 2 48" DIA
TYPE 2 48" DIA
TYPE 2 48" DIA
SHEET
OF
SHEETS
.
Washington State
Department of Transportation
-
LEGEND
POST IMPERVIOUS AREA
IMPERVIOUS AREA TO BE REMOVED
NEW IMPERVIOUS AREA
DATUM
(NAVD) 88
100 200
SCALE IN FEET
0
N
3
4
T
H
S
T
T.23N. R.5E. W.M.T.24N. R.5E. W.M.
N
E
3
0
T
H
S
T
SCHOOL
ELEMENTARY
KENNEYDALE
CLOVER CREEK
MEADOW AVE N.
N
E
2
8
T
H
S
T
SB 1-405
NB 1-405
M
A
T
C
H
T
O
S
H
E
E
T
5
M
A
T
C
H
T
O
S
H
E
E
T
7
6
19
I-405
RENTON TO BELLEVUE
CORRIDOR WIDENING & EXPRESS TOLL LANES
SHEET 6
AREA = 2.04 AC
TDA - CL1 - CLOVER CREEK
AREA = 86.97 AC
TDA - W1-2 - LAKE WASHINGTON
AREA = 4.97 AC
TDA - M - MAY CREEK
AREA = 2.04 AC
TDA - CL1 - CLOVER CREEK
MB MB
M
B
MB
M B
M B
M B
MBMBMBMB
MB
M
B
M
B
M
B
U
U
U
U
U
U
C
C
C
C
C
C
T
W
W
W
W
S
S
M
B
T
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
G
G
G
G
G
MP 6.80
MP 6.85
MP 6.90
MP 6.95
MP 7.00
MP 7.05 MP 7.10 MP 7.15 MP 7.20
SHEET
OF
SHEETS
.
Washington State
Department of Transportation
-
LEGEND
POST IMPERVIOUS AREA
IMPERVIOUS AREA TO BE REMOVED
NEW IMPERVIOUS AREA
DATUM
(NAVD) 88
100 200
SCALE IN FEET
0
M
A
T
C
H
T
O
S
H
E
E
T
6
M
A
T
C
H
T
O
S
H
E
E
T
8SB-405
NB-405
T.24N. R.5E. W.M.
7
19
I-405
RENTON TO BELLEVUE
CORRIDOR WIDENING & EXPRESS TOLL LANES
SHEET 7
AREA = 86.97 AC
TDA - W1-2 - LAKE WASHINGTON
AREA = 4.96 AC
TDA - M - MAY CREEK
T
MB
M
B
MB
S
T
T
U
U
U
C
C
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
C
C
C
C
C
C
C
C
CCC
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
CC
C
C
C
C
C
C
C
C
C
W
P
W
W
W
W
W
W
T
W
W W
W
T
W
W
T
W
W
S
S
W
W
U
U
U
U
U
U
U
U
UU
U
U
U U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
G
G
G
G
G
G
G
MP 7.25
MP 7.30
MP 7.35 MP 7.40 MP 7.45
MP
7
.50
MP
7
.55
MP
7
.60
MP
7
.65
MP
7
.70
MP 7.75
C
S
T
W
2 4 " R C P
2@42" sssp 0.66%
4 8 " S t e e l 0 .3 6 %
6 6 " s s s p 0 .6 6 %
48 IN STEEL WITH A CONCRET APRON
24 IN CONC
24 IN. CMP
24 IN. CMP (COR METAL PIPE)
18 IN. CMP
SHEET
OF
SHEETS
.
Washington State
Department of Transportation
-
LEGEND
POST IMPERVIOUS AREA
IMPERVIOUS AREA TO BE REMOVED
NEW IMPERVIOUS AREA
DATUM
(NAVD) 88
100 200
SCALE IN FEET
0
T.24N. R.5E. W.M.
M
A
T
C
H
T
O
S
H
E
E
T
7
SB I-405
NB I-405
8
19
I-405
RENTON TO BELLEVUE
CORRIDOR WIDENING & EXPRESS TOLL LANES
SHEET 8
M
A
T
C
H
T
O
S
H
E
E
T
9
SB I-405 ON RAMP
NB I-405 OFF RAMP
S
B
I
-
4
0
5
O
F
F
R
AM
P
H
A
Z
E
LW
O
O
D
LA
N
E
/
S
E
A
H
AW
K
S W
A
Y
E
A
S
T
S
ID
E
R
A
IL
C
O
R
R
ID
O
R
H
E
A
D
Q
U
A
R
T
E
R
S
S
E
A
T
T
L
E
S
E
A
H
AW
K
S
S
E
A
H
AW
K
S W
A
Y
NB I-405 ON RAMP
GYPSY CREEK
PUBLIC STORAGE
N
E
4
4
T
H
S
T
S
E
7
6
T
H
S
T
N
E
4
4
T
H
S
T
N
E
4
3
R
D
S
T
L
A
K
E
W
A
S
HI
N
G
T
O
N
B
L
V
D
N
M A Y C
R
E
E
K
GYPSY CREEK
BEEN UPDATED AS A CABS
THIS DETENTION POND HAS
AREA = 86.97 AC
TDA - W1-2 - LAKE WASHINGTON
CATCHMENT AREA = 29.69 ACRE PGIS
DIMENSIONS = 2-168'(L) X 21'(W); 4:1 (SIDE SLOPE)
BIOSWALE - CABS W1.2.1
CATCHMENT AREA = 0.55 ACRE PGIS
DIMENSIONS = 107'(L) X 2'(W); 3:1 (SIDE SLOPE)
BIOSWALE - CABS W1.2.3
CATCHMENT AREA = 28.81 ACRE PGIS
DIMENSIONS = 2-168'(L) X 20'(W); 3:1 (SIDE SLOPE)
BIOSWALE - CABS W1.2.2
TREATMENT TO BE REMOVED
EXISTING STORMWATER
REMOVED
TREATMENT TO BE
EXISTING STORMWATER
SWALE TO REMAIN
EXISTING BIORETENTION
AREA = 5.74 AC
TDA - M-2 - MAY CREEK
PARK & RIDE LOT
CATCHMENT AREA = 5.28 AC
DIMENSIONS: T.B.D.
BIOSWALE CABS M2.1
C
C
C
U
U
M
B
M
B
C
M
B
M
B
MBMBMBMBMB
U
M
B
M
B
M
B
M
B
M
B
M
B
U
M
B
M
B
M
B
M
B
M
B
U
U
U
U
U
C
U
U
M B
M B
M
B
C
MBMB
MB
M B M B
M B M BMBMB
M B
T
MB
M B
U
M B
U
U
U
U
U
C
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
G
G
G
G
G
G
M
P
7.
7
5
M
P
7
.80
MP 7.85 MP 7.90
MP 7.95
MP 8.00
MP 8.05
MP 8.10 MP 8.15 MP 8.20 MP 8.25
1
8
"
C
C
P
1
8
"
C
C
P
1
8
"C
C
P
1
8
"C
C
P
1
8
"P
S
C
P
12"MCP
1
2
"M
C
P
1
8
"
C
C
P
1
8
"
C
C
P
8
"
U
D
P
f
r
o
m
g
o
o
g
l
e
m
a
p
S
c
u
p
p
e
r
b
a
r
r
i
e
r
2
l
o
c
a
t
i
o
n
s
a
s
s
u
m
e
d
SHEET
OF
SHEETS
.
Washington State
Department of Transportation
-
LEGEND
POST IMPERVIOUS AREA
IMPERVIOUS AREA TO BE REMOVED
NEW IMPERVIOUS AREA
DATUM
(NAVD) 88
100 200
SCALE IN FEET
0
EASTSIDE RAIL CORRIDOR
S
T
R
E
A
M
8
.
1
5
LAKE
WASH
INGTON
BLVD
SE
S
T
R
E
A
M
7.8
RIPLEY LN N
SB I-405
NB I-405
T.24N. R.5E. W.M.
M
A
T
C
H
T
O
S
H
E
E
T
1
0
M A T
C
H
T O
S
H
E
E
T 8
9
19
I-405
RENTON TO BELLEVUE
CORRIDOR WIDENING & EXPRESS TOLL LANES
SHEET 9
AREA = 1.10 AC
TDA - W1-3 - LAKE WASHINGTON
AREA = 2.30 AC
TDA - W1-5 - LAKE WASHINGTON
AREA = 2.12 AC
TDA - W1-4 - LAKE WASHINGTON
AREA = 86.97 AC
TDA - W1-2 - LAKE WASHINGTON
STREAM 7.7A
C
T
M BMB M B
C
MB
C
C
MBMB
U
U
CCC
V
M
S
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
UU U
U
U
G
G
G
MP 8.30 MP 8.35 MP 8.40 MP 8.45 MP 8.50
MP 8.55
MP 8.60
MP
8.65
M
P
8
.
7
0
2 4 "P
S
C P
1
8
"P
S
C
P
1
2
"M
C
P
1
8
"P
S
C
P
1
8
"P
S
C
P
1
8
"P
S
C
P
SHEET
OF
SHEETS
.
Washington State
Department of Transportation
-
LEGEND
POST IMPERVIOUS AREA
IMPERVIOUS AREA TO BE REMOVED
NEW IMPERVIOUS AREA
DATUM
(NAVD) 88
100 200
SCALE IN FEET
0
T.24N. R.5E. W.M.
110TH AVE SE
S
T
R
E
A
M
8
.
4
106TH AVE SE
SB I-405
NB I-405
M
A T
C
H
T O
S
H
E
E
T
1
1
10
19
I-405
RENTON TO BELLEVUE
CORRIDOR WIDENING & EXPRESS TOLL LANES
SHEET 10
M
A
T
C
H
T
O
S
H
E
E
T
9
AREA = 2.30 AC
TDA - W1-5 - LAKE WASHINGTON
AREA = 3.55 AC
TDA - W1-6 - LAKE WASHINGTON
AREA = 88.75 AC
TDA - W1-2 - LAKE WASHINGTON
AREA = 3.55 AC
TDA - W1-6 - LAKE WASHINGTON
AREA = 13.92 AC
TDA - W2-1 - LAKE WASHINGTON