HomeMy WebLinkAboutReport 6 3 of 4(i)
King County
Department of Development
and Environmental Services
900 Oakesdale Avenue SW
Renton, WA 98055-1219
November 17, 2005
Robert Wenzl
Belmont Homes, Inc.
P.O. Box 2401
Kirkland, WA 98083
Robert H. Stevens, P.E.
Core Design, Inc.
14711 NE 29�h Place, #101
Bellevue, WA 98007
RE: Talbot Ridge Subdivision 2005 KCSWDM Adjustment Request(File No. L05V0061)
Dear Applicant and Engineer:
The Land Use Services Division, Engineering Review Section, has completed review of the
adjustment request for the Talbot Ridge subdivision, You are requesting approval for an
adjustment from the 2005 King County Surface Water Design Manual (KCSWDM) Core
Requirement No. 1, Section 1.2.1, Discharge at the Natural Location. Our review of the
information and a site visit provides the following findings:
The proposed Talbot Ridge subdivision is located adjacent to the southwest corner of
the intersection of SE 192nd Street and 102nd Avenue SE. The 27 lot, 4.36 acre,
proposed Talbot Ridge subdivision is filed under Land Use Services Division (LUSD)
file number L05P0007.
2. The Talbot Ridge subdivision is located in the Springbrook Creek tributary area, Black
River subbasin of the Lower Green River basin. The site is subject to the
Conservation (Level Two) flow control and Basic water quality requirements of the
2005 KCSWDM.
The east -west oriented rectangular site slopes moderately from east to west. The
western edge of the site contains slopes steep enough to prevent development.
Sheetflow from the site then enters the backyards of the lots on the east side of 991h
Place South, migrates through the lots and ends up on 991h Place South. The 991h Place
South drainage system directs flows south and enters the Springbrook Park watershed
area characterized by very steep slopes and designated landslide and erosion hazard
areas. Flow continues west through the watershed area until passing west via culvert
under Talbot Road South. Flow continues northwest through the Spri%brook Trout
Farm, a designated wetland area and then crosses north under South 55' Street (the
City of Renton's designation for SE 192nd Street) and turns west to pass under
Highway 167. By this time, the stream is designated salmonid. Very little upstream
flow enters the site.
Talbot Ridge/LO5V0061
November 17, 2005
Page 2 of 3
4. The proposal is to collect most runoff from the project site and direct it to a single
detention and water quality facility located near the northwest corner of the site just
shy (east) of the steep slope area. The allowed release would then be conveyed to the
western property line that abuts the right-of-way and outlet to an open ditch. Flow
would then enter a catch basin on the south side of SE 192"d Street and be diverted
from its natural discharge location by crossing to the north side of the road. Drainage
would continue west along the north side of SE 192"d Street. After crossing Talbot
Road South, the diverted downstream path would realign with the original
downstream path before reaching Highway 167. Nuisance flows to the abutting lots
on the western property line would see sheetflow significantly reduced, There would
be a reduction in flows through the landslide and erosion hazard areas of the
Springbrook watershed. Frontage improvements are included in the conceptual
drainage plan.
5. No decorative ponds or shallow wells have been identified that would be affected by
the proposed diversion.
6. The Level One Drainage Analysis identified no restrictions or problems associated
with the proposed discharge location. In fact, it is the natural discharge location that
has experienced drainage complaints. Where flows enter the watershed area at the
southern end of 99"' Place South erosion has been reported. In addition, the
downstream Trout Farm has experienced erosion problems from suspended sediments
during new construction. The diverted path would help to reduce these occurrences.
Based on these findings, we hereby approve this adjustment to allow the off -site diversion of
runoff from the stormwater facility draining to the north side of South 192nd Street with the
following conditions:
1. The release rates for the detention facility will be based on the tributary area being
directed to the facility.
2. The volume for the detention facility will be based on all flows directed to the facility
at full development under current zoning. The allowed release rate will be reduced by
any undetained flows that would bypass the proposed subdivision drainage facilities.
The detention volume shall be sized using the Conservation flow control standard in
the 2005 KCSWDM. A 10 to 20 percent volumetric factor of safety must be applied
to all storm events requiring detention. The design Technical Information Report shall
state the factor of safety selected and the basis of that determination.
3. Water quality facilities must be sized based on the entire proposed subdivision
draining to the facilities including any required frontage improvements.
4. All onsite or offsite drainage facilities must be located in a public right-of-way,
recreation space tract with easement or storm drainage tract dedicated to King County.
Talbot Ridge/1,05V0061
November 17, 2005
Page 3 of 3
5. Additional storm drainage requirements identified by SEPA or the plat hearing review
will apply to this project. The applicant retains all rights and privileges afforded in
Section 1.4.
If you have any further questions regarding this KCSWDM adjustment or the design
requirements, please contact Mark Bergam at (206) 296-7270.
Sincerely,
James Sanders, P.E.
Development Engineer
Engineering Review Section
Land Use Services Division
Jim Chan, P.E.
Supervising Engineer
Site Engineering and Planning Section
Building Services Division
CC' Curt Crawford, P.E., Managing Engineer, Stormwater Services Section, KCDNR
Bruce Whittaker, Engineer III, Engineering Review Section, LUSD
Trisha Bull, Project/Program Manager II, Current Planning Section, LUSD
Mark Bergam, P.E., Engineer III, Engineering Review Section, LUSD
# Surface Water Design Manual
KingC°mot'' Requirements 1 Standards
Deparimcnt of Development and Environmental So -vices q
entmWashi Washington
055-12Southw9 Adjustment* Request
Renton, Washington 48l}55-1279
Project Name:
DDES Project Flo No.: L05P0007
Talbot Ridge Estates
DDES EngineerlPianner dame:
Bruce Whitaker l
Trishah Ball
Project Address:
Design Engineer-.
Phone.
19200 102nd Avenue SE
Robert StevorL5,.
PE 425-885-7877
Applcant/Aaent
Phone:
Signaturw.
.:.
Date:
Belmrxit Homes
206-714-7161
q - C�
Sig
Engineering Firm Name:
aoAla-5.
Core Design, Inc.
Addm-ss,
Cffy, Stafe, Zip Code:
Address:
City, State, Zip Code:
14711 NE 29th P1.
#101, Bellevue,
WA, 98007
INSTRUCTIONS TO APPLICANTIDESIGN ENGINEER:
Please be sure to include all plans (f.I.R., if available), sketches, photos and maps that may assist in complete review and consideration
of this adjustment request_ Failure to provide all pertinent informatbn may result in delayed processing or denial of your request.
Please submit buo wmplerte copies of this reguest. apiDlIatL9nto the DDES intake Counter, at 900 Oakesdale
Avenue Southwest, Renton, Washington 9W055-1219. For additional information, phone Randal Parsons, P.E., at (206) 296-7207.
REFER To SECTION 1.4 IN CHAPTER 1 OF THE SMLVAC8 WATER DESIGN XMMAL FOR ADAIISTltEETB
DESCRIPTION OF ADJUSTMENT REQUEST: 13 Standard M Complex 0 Expedmental ❑ Blanket
❑ Pre -application
APPLICABLE VERSION KCSWDM: ❑ 1990 (11195). 131998 (9198) 11 2005
• (Note: the term "variance" replaced by "adjustment")
APPLICABLE SECTION(S) OF STANDARDS:
Core Requirement 01 RMOF
JUSTIFICATION PER KCSWDM SECTION 1.4.2
❑ see attachments listed below. AUG f 9 2005
MUNAI UKt7:
❑ Approval
❑ DNRMLRD Approval Signed:
S Staff Recommendation Signed:
iltions of Appravai:
�i Conditional Approval (see below)
See attached Memo Dated: it " 1 — p
K.C. D.D.E.S.
❑ Denial
Date: (Experimental & Blanket variances only)
Date: K `17'-'Or
Land Use Services Div., Engineering Review Supervisor IDDES, Bldg. Serv.
F99 /SRS/SWU4 -AW - do
F96/MS/SWIM-S. opy22. dos 11/17/99 cic
I Signed:
et,
LosvooG/
Talbot Ridge Estates - Adjustment Justification
An adjustment is requested to Core Requirement #1 — Discharge at the Natural Location,
Section 1.2.1 of the 1998 King County Surface Water Design Manual for the Talbot
Ridge Estates project.
Currently the site's stormwater sheet flows to the west property line to the rear yards of
the adjacent lots which front onto 99`h Place S_ The drainage then flows to the south
through an existing storm drain system on 99`' Place S. Once to the south end of 99'h
Place S., the stormwater discharges through an SAO Landslide Hazard Area and then on
to an SAO Erosion Hazard area. Drainage complaints 2003-0194 and 1998-0461 have
been filed relating to slippage of the landslide hazard area at the south end of 99d' Place
S. After the stream exits the SAO Erosion Hazard area, it joins with Springbrook Creek,
crosses under Talbot Rd. and passes through the Gallagher property, a trout farm with a
history of siltation due to neighboring developments. Drainage complaint 1998-0045 has
been filed relating to silt entering the trout farm pond. The flow then discharges into an
SAO Class 2 wetland. The flow exits the northwest edge wetland and flows north under
S. 192°d St. and continues northwest. This point is approximately 0.6 miles from the
project site.
We have proposed a discharge location that will connect the discharge from the site into
an existing storm drainage that runs west along S. 192"d St. The system crosses under
Talbot Rd_ S. and continues west until discharging into Springbrook Creek, converging
on the discharge location stated above, approximately 0.6 miles from the project site.
There are no SAO hazard areas or drainage complaints associated with this drainage
route.
The proposed discharge of stormwater into the system on S. 192"d St. fulfills all the
criteria for granting an adjustment which are:
1 _ To produce a compensating and comparable result that is in the public interest, AND
2. To meet the objectives of safety, function, appearance, environmental protection and
maintainability based on sound engineering judgement.
For these reasons we request this adjustment to the discharge location.
E -FI" 9 2 � WED
AUK 19 2005
K.C. D.D.E.S.
LOSV00C01
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2005
1-0
K.C. D. D. E. S. NORTH
LA-
M ERR1e y SCALE: 1"=00'
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DOWNSTREAM DRAINAGE ROUTES
�d 'fill a a�'S�•. _ - !~` + _ _
'x3 ��tit � -� :; _ ` � � 4� � �•� Y TALBOT RIDGE
CORE PROJECT NO.04120
., .i$O .�F' ! �"� i i - -)1 '^ �`a� - •' Y � . .. , 'mac _... _.
King County
Department of Development
and Environmental Services
900 Oakesdale Avenue SW
Renton, WA 98055-1219
November 17, 2005
Robert Wenzl Robert H. Stevens, P.E.
Belmont Homes, Inc. Core Design, Inc.
P.O. Box 2401 14711 NE 29Eh Place, #101
Kirkland, WA 98083 Bellevue, WA 98007
RE: Talbot Ridge Subdivision 2005 KCSWDM Adjustment Request (File, No. L05V0061)
Dear Applicant and Engineer:
The Land Use Services Division, Engineering Review Section, has completed review of the
adjustment request for the Talbot Ridge subdivision. You are requesting approval for an
adjustment from the 2005 King County Surface Water Design Manual (KCSWDM) Core
Requirement No. 1, Section 1.2.1, Discharge at the Natural Location. Our review of the
information and a site visit provides the following findings:
1. The proposed Talbot Ridge subdivision is located adjacent to the southwest corner of
the intersection of SE 192nd Street and 102" d Avenue SE. The 27 Iot, 4.36 acre,
proposed Talbot Ridge subdivision is filed under Land Use Services Division (LUSD)
file number L051`0007.
2. The Talbot Ridge subdivision is located in the Springbrook Creek tributary area, Black
River subbasin of the Lower Green River basin. The site is subject to the
Conservation {Level Two) flow control and Basic water quality requirements of the
2005 KCSWDM.
The east -west oriented rectangular site slopes moderately from east to west. The
western edge of the site contains slopes steep enough to prevent development.
Sheetflow from the site then enters the backyards of the lots on the east side of 991h
Place South, migrates through the lots and ends up on 99`' Place South. The 991h Place
South drainage system directs flows south and enters the Springbrook Park watershed
area characterized by very steep slopes and designated landslide and erosion hazard
areas. Flow continues west through the watershed area until passing west via culvert
under Talbot Road South. Flow continues northwest through the Springbrook Trout
Farm, a designated wetland area and then crosses north under South 55` Street (the
City of Renton's designation for SE 192n1 Street) and turns west to pass under
Highway 167. By this time, the stream is designated salmonid. Very little upstream
flow enters the site.
Talbot Ridge/LO5V0061
November 17, 2005
Page 2of3
4. The proposal is to collect most runoff from the project site and direct it to a single
detention and water quality facility located near the northwest corner of the site just
shy (east) of the steep slope area. The allowed release would then be conveyed to the
western property line that abuts the right-of-way and outlet to an open ditch. Flow
would then enter a catch basin on the south side of SE 192"d Street and be diverted
from its natural discharge location by crossing to the north side of the road. Drainage
would continue west along the north side of SE 192"d Street. After crossing Talbot
Road South, the diverted downstream path would realign with the original
downstream path before reaching Highway 167. Nuisance flows to the abutting lots
on the western property line would see sheetflow significantly reduced. There would
be a reduction in flows through the landslide and erosion hazard areas of the
Springbrook watershed. Frontage improvements are included in the conceptual
drainage plan.
5. No decorative ponds or shallow wells have been identified that would be affected by
the proposed diversion.
6. The Level One Drainage Analysis identified no restrictions or problems associated
with the proposed discharge location. In fact, it is the natural discharge location that
has experienced drainage complaints. Where flows enter the watershed area at the
southern end of 99th Place South erosion has been reported. In addition, the
downstream Trout Farm has experienced erosion problems from suspended sediments
during new construction. The diverted path would help to reduce these occurrences.
Based on these findings, we hereby approve this adjustment to allow the off -site diversion of
runoff from the stormwater facility draining to the north side of South 192nd Street with the
following conditions:
1. The release rates for the detention facility will be based on the tributary area being
directed to the facility.
2. The volume for the detention facility will be based on all flows directed to the facility
at full development under current zoning. The allowed release rate will be reduced by
any undetained flows that would bypass the proposed subdivision drainage facilities.
The detention volume shall be sized using the Conservation flow control standard in
the 2005 KCSWDM. A 10 to 20 percent volumetric factor of safety must be applied
to all storm events requiring detention. The design Technical Information Report shall
state the factor of safety selected and the basis of that determination.
3. Water quality facilities must be sized based on the entire proposed subdivision
draining to the facilities including any required frontage improvements.
4. All onsite or offsite drainage facilities must be located in a public right-of-way,
recreation space tract with easement or storm drainage tract dedicated to King County.
Talbot Ridge/1,05V0061
November 17, 2005
Page 3 of 3
5. Additional storm drainage requirements identified by SEPA or the plat hearing review
will apply to this project. The applicant retains all rights and privileges afforded in
Section 1.4.
If you have any further questions regarding this KCSWDM adjustment or the design
requirements, please contact Mark Bergam at (206) 296-7270.
Sincerely,
9TA�
James Sanders, P.E.
Development Engineer
Engineering Review Section
Land Use Services Division
Jim Chan, P.E.
Supervising Engineer
Site Engineering and Planning Section
Building Services Division
CC' Curt Crawford, P.E., Managing Engineer, Stormwater Services Section, KCDNR
Bruce Whittaker, Engineer III, Engineering Review Section, LUSD
Trisha Bull, Project/Program Manager II, Current Planning Section, LUSD
Mark Bergam, P.E., Engineer I11, Engineering Review Section, LUSD
r
0 Surface Water Design Manual
KingCm°ty Requirements 1 Standards
Department of Develapme�e# and Enviranme6tal Services
9004ak`sdmleAvenue
Southwest 99055-1219 Adjustment* Request
Renton, "Washington
Project Name:
ODES Project Fie No.: L05P0007
Talbot Ridge Estates
DOES EngineerlPlanner Name:
Bruce Whitaker / Trishah Ball
Project Address:
Design Englnear.
Phone:
19200 102nd Avenue SE
Robert Stew
PE 425-885-7877
Applicartt/Agent:
Phone:
Slgnature 41
Date:
Belmont Haines IAIC
206-714-7161P�s.4'
Sig
e:
Engineering Firm Name:
4 /
Core Design, Inc,
Address;:
C , Sta e, Zip Code:
Address:
City, State, Zip Code:
14711 NE 29th Pl.
#101, Bellevue,
WA, 98007
INSTRUCTIONS TO APPLICANTMESIGN ENGINEER:
Please be sure to include all plans (T_i.R., If avallable), sketches, photos and maps that may assist in complete review and consideration
of this adjustment request. Failure to provkie all pertinent Information may result In delayed processing or denial of your request.
Please submit two carrrolete conies of this request. application form. aad poWicable fee to the DDES Intake Counter, at 9W Oakesdele
Avenue Southwest, Renton, Washington 9BD55-1219. For additional information, phone Randall Parsons, P.E., at (206) 296-7207.
REFER TO SECTION I.4 IN CEAPTER 1 OF THE SURFACE ]WATER DESI(W XRNOAL FOR AEJUSTIlbZNTB
DESCRIPTION OF ADJUSTMENT REQUEST: 13 Standard n Complex ❑ Experimental ❑ Blanket
❑ Pre -application
APPUCABLE VERSION KCSWDM: ❑ 1990 (11195)' 131998 (9/98) 12 217(].5
(Note: the term "variance" replaced by "adjustment")
APPLICABLE SECTION(S) OF STANDARDS:
Core Requirement 91 ❑ � � � �j [�/�
JUSTIFICATION PER KCSWDM SECTION 1.4.2
❑ See attachments listed below. AUG 1' 9 2005
K.C. D.D.E.S.
4UTHOKIZATIUN SiU
n Approval 8E Conditional Approval (see below) ❑ Denlal
❑ DNRNVLRD Approval Signed: Date: (Experimental & Blanket variances only)
ODES Staff Recommendation Signed: Dane: 0-11r-or
Conditions of Approval:
See attached Memo Dated:
ODES DIRECTOR/DESIGNEE:
DOES, Land Use Services Div., Engineering Review Suporvisor. DOES, Bldg. Serv. Div., Slte Engineering & Planning
Supervisor.
ned: Signed:
Date: j �•� Dat lr a
F99/ERE/rW M-AW.dW
F96/M/SK Mx-S.epy22.dac 32/17/99 alp
LOSVOO�o1
Talbot Ridge Estates _ Adiustment Justification
An adjustment is requested to Core Requirement #1 — Discharge at the Natural Location,
Section 1.2.1 of the 1998 King County Surface Water Design Manual for the Talbot
Ridge Estates project.
Currently the site's stormwater sheet flows to the west property line to the rear yards of
the adjacent lots which front onto 99 h Place S. The drainage then flows to the south
through an existing storm drain system on 99th Place S. Once to the south end of 99th
Place S., the stormwater discharges through an SAO Landslide Hazard Area and then on
to an SAO Erosion Hazard area. Drainage complaints 2003-0194 and 1998-0461 have
been filed relating to slippage of the landslide hazard area at the south end of 99`h Place
S. After the stream exits the SAO Erosion Hazard area, it joins with Springbrook Creek,
crosses under Talbot Rd. and passes through the Gallagher property, a trout farm with a
history of siltation due to neighboring developments. Drainage complaint 1998-0045 has
been filed relating to silt entering the trout farm pond. The flow then discharges into an
SAO Class 2 wetland. The flow exits the northwest edge wetland and flows north under
S. 192nd St. and continues northwest. This point is approximately 0.6 miles from the
project site.
We have proposed a discharge location that will connect the discharge frorn the site into
an existing storm drainage that runs west along S. 192"d St. The system crosses under
Talbot Rd. S. and continues west until discharging into Springbrook Creek, converging
on the discharge location stated above, approximately 0.6 miles from the project site.
There are no SAO hazard areas or drainage complaints associated with this drainage
route.
The proposed discharge of stormwater into the system on S_ 192"d St. fulfills all the
criteria for granting an adjustment which are:
1 _ To produce a compensating and comparable result that is in the public interest, AND
2. To meet the objectives of safety, function, appearance, environmental protection and
maintainability based on sound engineering judgement.
For these reasons we request this adjustment to the discharge location.
n[-E, 9 2 1 W E D
AU-3 19 2005
K.C. D.D.E.S.
LVS V OO�01 [ILL e < ot, �
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DOWNSTREAM DRAINAGE ROUTES
f :..
TALBQT RIDGE
COREPROJECT NO.04120
(i)
King County
Department of Development
and Environmental Services
900 Oakesdale Avenue SW
Renton, WA 98055-1219
November 17, 2005
Robert Wenzl
Robert H. Stevens, P.E.
Belmont Homes, Inc. Core Design, Inc.
P.O. Box 2401 14711 NE 29t' Place, # 101
Kirkland, WA 98083 Bellevue, WA 98007
RE: Talbot Ridge Subdivision 2005 KCSWDM Adjustment Request (File No. L05V0061)
Dear Applicant and Engineer:
The Land Use Services Division, Engineering Review Section, has completed review of the
adjustment request for the Talbot Ridge subdivision. You are requesting approval for an
adjustment from the 2005 King County Surface Water Design Manual (KCSWDM) Core
Requirement No. 1, Section 1.2.1, Discharge at the Natural Location. Our review of the
information and a site visit provides the following findings:
I. The proposed Talbot Ridge subdivision is located adjacent to the southwest corner of
the intersection of SE 192nd Street and 102"d Avenue SE. The 27 lot, 4.36 acre,
proposed Talbot Ridge subdivision is filed under Land Use Services Division (LUSD)
file number L05P0007.
2. The Talbot Ridge subdivision is located in the Springbrook Creek tributary area, Black
River subbasin of the Lower Green River basin. The site is subject to the
Conservation (Level Two) flow control and Basic water quality requirements of the
2005 KCSWDM.
The east -west oriented rectangular site slopes moderately from east to west. The
western edge of the site contains slopes steep enough to prevent development.
Sheetflow from the site then enters the backyards of the lots on the east side of 99th
Place South, migrates through the lots and ends up on 99d' Place South. The 99t' Place
South drainage system directs flows south and enters the Springbrook Park watershed
area characterized by very steep slopes and designated landslide and erosion hazard
areas. Flow continues west through the watershed area until passing west via culvert
under Talbot Road South. Flow continues northwest through the Sprin&brook Trout
Farm, a designated wetland area and then crosses north under South 55 Street (the
City of Renton's designation for SE 192nd Street) and turns west to pass under
Highway 167. By this time, the stream is designated salmonid. Very little upstream
flow enters the site.
Talbot Ridge/L05V0061
November 17, 2005
Page 2 of 3
4. The proposal is to collect most runoff from the project site and direct it to a single
detention and water quality facility located near the northwest corner of the site just
shy (east) of the steep slope area. The allowed release would then be conveyed to the
western property line that abuts the right-of-way and outlet to an open ditch. Flow
would then enter a catch basin on the south side of SE 192"d Street and be diverted
from its natural discharge location by crossing to the north side of the road. Drainage
would continue west along the north side of SE 192"d Street. After crossing Talbot
Road South, the diverted downstream path would realign with the original
downstream path before reaching Highway 167. Nuisance flows to the abutting lots
on the western property line would see sheetflow significantly reduced. There would
be a reduction in flows through the landslide and erosion hazard areas of the
Springbrook watershed. Frontage improvements are included in the conceptual
drainage plan.
5. No decorative ponds or shallow wells have been identified that would be affected by
the proposed diversion.
6. The Level One Drainage Analysis identified no restrictions or problems associated
with the proposed discharge location. In fact, it is the natural discharge location that
has experienced drainage complaints. Where flows enter the watershed area at the
southern end of 991h Place South erosion has been reported. In addition, the
downstream Trout Farm has experienced erosion problems from suspended sediments
during new construction. The diverted path would help to reduce these occurrences.
Based on these findings, we hereby approve this adjustment to allow the off -site diversion of
runoff from the stormwater facility draining to the north side of South 192"d Street with the
following conditions:
1. The release rates for the detention facility will be based on the tributary area being
directed to the facility.
2. The volume for the detention facility will be based on all flows directed to the facility
at full development under current zoning. The allowed release rate will be reduced by
any undetained flows that would bypass the proposed subdivision drainage facilities.
The detention volume shall be sized using the Conservation flow control standard in
the 2005 KCSWDM. A 10 to 20 percent volumetric factor of safety must be applied
to all storm events requiring detention. The design Technical Information Report shall
state the factor of safety selected and the basis of that determination.
3. Water quality facilities must be sized based on the entire proposed subdivision
draining to the facilities including any required frontage improvements.
4. All onsite or offshe drainage facilities must be located in a public right-of-way,
recreation space tract with easement or storm drainage tract dedicated to King County.
Talbot Ridge/1,05V0061
November 17, 2005
Page 3 of 3
5. Additional storm drainage requirements identified by SEPA or the plat hearing review
will apply to this project. The applicant retains all rights and privileges afforded in
Section 1.4.
If you have any further questions regarding this KCSWDM adjustment or the design
requirements, please contact Mark Bergam at (206) 296-7270.
Sincerely,
James Sanders, P.E.
Development Engineer
Engineering Review Section
Land Use Services Division
Jim Chan, P.E.
Supervising Engineer
Site Engineering and Planning Section
Building Services Division
cc: Curt Crawford, P.E., Managing Engineer, Stormwater Services Section, KCDNR
Bruce Whittaker, Engineer III, Engineering Review Section, LUSD
Trisha Bull, Project/Program Manager II, Current Planning Section, LUSD
Mark Bergam, P.E,, Engineer III, Engineering Review Section, LUSD
Surface Water Design Manua!
King County Requirements I Standards
Depaetment oiDevdopment and Envinl�enist Set -Am q
9WOakestWeAveane5ouffi% st Adjustment* Request
Renton, Washingan "055-1219
Project Name:
DDES Project F®e No.: L05P0007
Talbot Ridge Estates
DOES EnginearRianner Name:
Bruce Whitaker /
Trishah Ball
Project Address:
Design
Phone:
19200 102nd Avenue SE
Robert
425-$85-7877
ANAmNAgent Phone:
5igrtatteae:
Belmont IiafiteS 206-714--7161
�f*l y. k
s
Engineering Rm Nwo
" 4011 a�
Care DesLM, Inc,
Addrew. city, Stdo, Zip Coda:
Address:
CRY, Stale, Zip Code:
Z (j
14711 NE 29th Pl.
#101, Bellevue,
WA, 961JU
INSTRUCTIONS TO APPLICANTIDESIGN ENGINEER:
Please be sure to include all plans (T_I.R., if available), sketches, photos and maps that may assist in complete review and consideration
al this adjustment request Fdure to provide all pertinent Inkaralion may result In delayed processing or denial of your request.
Please to the DDES Intake Counter, at 9W Oakesdale
Avenue Sauormst. Renton, Washington 98055-1219. For additional kdomtation, pia Randall Pamom, P.E., at RN) 295-7207.
RBFER TO SIMEON 1.4 rK CRAPTZR 1 OF THE S=FAC1t WATER DEMN 10tt'tFAL FOR AWUOTKUITS
DESCRIPTION OF ADJUSTMENT REQUEST: 13 Standard 10 Complex 17 EMYNtnental ❑ Blanket
0 Pre -application
APPLICABLE VERSION KCSWDM: ❑ 1990 (11195)' CI isss ON) Ia 201115_
*(Note: the term 'variance' replaced by 'adJushrantl
APPLICABLE SECTION(S) OF STANDARDS:
Core Requirement #1
JUSTIFICATION PER KCSWDM SECTION IA42
Cl See attachments listed below.
AUG 1' 9 2005
.1,'iUNAf UKCS:
0 Approval
0 DNRNVLRD Approval Signed:
5 Staff Recommendation Signed:
Imam of Approval:
jd see attached Memo Dated: _
PCnrnnttionel Approval (see below)
K.C. D.D.E.S
0 Denial
Date: (Eerhnental h Blanket variances only)
Data: A,_ Ir- 43
P99 ERS/8PIK-AW-AOC
r9d/iM/814,W-8. apy77. doe 11/17/99 cic
Gas vovCrl
Talbot Ridge Estates - Adjustment Justification
An adjustment is requested to Core Requirement #1 — Discharge at the Natural Location,
Section 1.2.1 of the 1998 King County Surface Water Design Manual for the Talbot
Ridge Estates project.
Currently the site's stormwater sheet flows to the west property line to the rear yards of
the adjacent lots which front onto 991h Place S. The drainage then flows to the south
through an existing storm drain system on 991" Place S. Once to the south end of 99'h
Place S., the stormwater discharges through an SAO Landslide Hazard Area and then on
to an SAO Erosion Hazard area. Drainage complaints 2003-0194 and 1998-0461 have
been filed relating to slippage of the landslide hazard area at the south end of 991h Place
S. After the stream exits the SAO Erosion Hazard area, it joins with Springbrook Creek,
crosses under Talbot Rd. and passes through the Gallagher property, a trout farm with a
history of siltation due to neighboring developments. Drainage complaint 1998--0045 has
been filed relating to silt entering the trout farm pond. The flow then discharges into an
SAO Class 2 wetland. The flow exits the northwest edge wetland and flows north under
S 192°d St. and continues northwest. This point is approximately 0.6 miles from the
project site.
We have proposed a discharge location that will connect the discharge from the site into
an existing storm drainage that runs west along S. 192nd St. The system crosses under
Talbot Rd. S. and continues west until discharging into Springbrook Creek, converging
on the discharge location stated above, approximately 0.6 miles from the project site.
There are no SAO hazard areas or drainage complaints associated with this drainage
route.
The proposed discharge of stormwater into the system on S. 192"d St. fulfills all the
criteria for granting an adjustment which are:
1. To produce a compensating and comparable result that is in the public interest, AND
2. To meet the objectives of safety, function, appearance, environmental protection and
maintainability based on sound engineering judgement.
For these reasons we request this adjustment to the discharge location.
AUG 19 2005
K.C. D.D.E.S.
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King County
Department of Development
and Environmental Services
Land Use Services Division
900 Oakesdale Avenue Southwest
Renton, Washington 98055-1219
206-296-6600 TTY 206-296-7217
Drop -Off G%ver. Sheet
for LUSD ONLY
For alternate formats, call 206-296-6600.
Drop -Off Cover Sheet for Land Use Services Division
kir**1nHrvr* **,Wrfr/r�e�rve*wlrwlrNR** IMPORTANT*:***"'*'**''***""`*,•'*,'"'k***+*
PROJECT NUMBER AND NAME IS NECESSARY
FOR ALL DROP-OFFS
Project No.:
Project Name: ��->Q%` IEI�14e ST T S
FRO
Date Received by LUSD
aE EDD � �� f I`L
AUG 2 9 2005
Company NarFie / Contact Person
Telephone NoO(p / — 7 /�o��' D'�'�''
ADDITIONAL INFORMATION REQUESTED BY KING COUNTY STAFF (please print)
Short Plat ! Plats
Please specify items) dropped -off:
Lot Line Adiustment Permit
Please specify item(s) dropped -off:
Right of Way Permit
Please specify item(s) dropped -off:
Clearing 1 Grading Permit — Additional information requested
Please specify item(s) dropped -off:
f P�
KI 11:11����
PLEASE NOTE: All drop-off items) will be logg6d into the computer under the project number, therefore, it is important
that the top portion of this form is completed properly before you drop-off anything_ Assistance in finding a project number
can be provided by speaking to a Zoning/Land Use Technician. Your cooperation is important. Thank you.
Check out the DDES Web site at www.metrokc.Qovlddes
Drop -Off Cover Sheet—LUSD Only Ig-cvs-dropoff.pdf 11-03-2004 Page 1 of 1
King County
Department of Development and Environmental Services
900 aakesdale Avenue Southwest
Renton, Washington 98055-1219
Certification of
Applicant Status
206-296-6600 TTY 206-296-7217 For alternate formats, call 206-296-6600.
Permit Number: 40 �5%-;>Q % Activity Number: 1-05
Permit Name:"/ STi�T. S
FOR INDIVIDUALS:
(print name), hereby certify that I am
thelan owner of the property which is the subject of this permit. If I am not the sole owner of the
property, 1 certify that I am authorized to represent all other owners of the property. My mailing
address is:
I further certify that I am the "Applicant" for this permit and as such am financially responsible
for all fees and will receive any refunds paid. I shall remain the "Applicant" for the duration of
this permit unless I transfer my "applicant" status in writing on a form provided by DDES.
Signature of Applicant
.OR -
FOR CORPORATIONSIBUSINESS ASSOCIATIONS:
Date Signed
I, j (print name), hereby certify that I am
an authorized agent of `, , a corporation or other
business association authorized to do business in the State of Washington, which is the sole
owner of the property that is the subject of this permit. If this corporation or business association
is not the sole owner of the property, I certify that this corporation/business association is
authorized to represent all other owners of the property. The mailing address of this
corporation/business association is:
I further certify that the above named corporation/business association is the "Applicant" for this
permit and as such is financial) res onsible for all fees and will receive any refunds paid..
This corporation/busin s asso ation shall remain the "Applicant" for the duration of this permit
unless it t sf s it lic status in writinq on a form provided by DDES.
Signatu a of Applicant's Agent Dat6 Signed
* By signing as the Applicant or the Applicant's Agent, I certify under penalty of perjury under the laws of
the State of Washington that the information provided above is true and correct.
Certification of Applicant 5tatusFORM Ic-cer-apstat.pdf 01/08/04 Page iof 2
E
King County
Department of Development and Environmental Services
900 Oakesdale Avenue Southwest
Renton, Washington 98055-1219
206-296-6600 M2o6-296-7217 For alternate formats, call 206-296-6600.
Permit Number: Activity Dumber: 11 --0t��
Permit Name: NL
FOR INDIVIDUALS:
I, (print name), hereby certify that I am
the/an owner of the property which is the subject of this permit, If I am not the sole owner of the
property, I certify that I am authorized to represent all other owners of the property. My mailing
address is:
further certify that I am the "Applicant" for this permit and as such am financially responsible
for all fees and will receive any refunds paid. I shall remain the "Applicant" for the duration of
this permit unless I transfer m "applicant" status in writing on a form provided by DDES.
Signature of Applicant Date Signed
-OR-
FOR CORPORATIONS/BUSINESS ASSOCIATIONS:
I, o EkT (print name), hereby certify that I am
an authorized agent of kV-J` , a corporation or other
business association authorized to do business in the State of Washington, which is the sole
owner of the property that is the subject of this permit. If this corporation or business association
is not the sole owner of the property, I certify that this corporation/business association is
authorized to represent all other owners of the property. The mailing address of this
corporation/business association is:
I further certify that the above named corporation/business association is the "Applicant" for this
permit and as such is financially res onsible !9K all few and will receive any refunds paid.
This corporation/basin ass��ccyyat�Ian shall r ai 'Applicant" for the duration of this permit
unless it transfers it o�ficalit4taKis iWw ' n a farm provided by DDE
Da Signed
* By signing as the Applicant or the Applicant's Agent, I certify under penalty of perjury under the laws of
the State of Washington that the information provided above is true and correct.
Certification of Applicant StatusFORM Ic-cer-apstat.pdf 01/08/04 Page 1of 2
NOTICE TO APPLICANTS: By law, this department returns all engineering and other
plans to the applicant. If, however, you wish to authorize the department to return
engineering and other plans directly to the engineer, architect, or other consultant for the
limited purpose of making corrections, please designate below:
❑ I authorize this department to return plans directly to my consultant(s) for the limited
purpose of making corrections as designated on this form.
CONSULTANTS:
Check out the DDES Web site at.www.metrokc.q()v1ddes
Certification of Applicant 5tatusFORM Ic-eer-apstat.pdf 01/08/04 Page 2 of 2
0
King County
Department of Development and Environmental Services
Land Use Services Division
900 Oakesdale Ave. Southwest
Renton, WA 98055-1219
August 25, 2005
Belmont Homes, Inc. Robert H. Stevens, P.E.
P.O. Box 2401 Core Design, Inc.
Kirkland, WA 98083 14711 NE 29th Place, #101
Bellevue, WA 98007
RE: Talbot Ridge Estates Preliminary PIat. L05P0007: 2005 KCSWDM Adiustment No.
L05VO061 - Notice of Complete Application
Dear Applicant/Engineer:
The purpose of this notice is to inform you that on August 25, 2005 the Land Use Services
Division, Engineering Review Section staff has determined this 2005 King County Surface Water
Design Manual (KCSWDM) adjustment application is COMPLETE under the requirements of
King County Code (KCC) Title 20. This determination establishes the beginning of the 120-day
time period for your application processing. However, supplemental information is required by the
Engineering Review Section staff for the continued review and processing of this 2005 KCSWDM
adjustment request.
Please provide two copies of the Certification of Applicant Status or Certification and Transfer of
Applicant Status forms, one or the other (but not both) depending on your circumstances.
Our goal is to process your application within 120 days, However, the complexity of your project,
level of analysis required, the quality of your submittal and available resources will affect the
actual review time. The time line can be impacted by one or more of the following actions that
will stop the 120-day clock:
• Any request made by the Engineering Review Section staff for additional information.
• Changes or revisions requested by the applicant(s).
• Mutually agreed upon request to stop the 120-day clock.
Should you have any questions, please contact me at (206)-296-7270 and FAX (206)-296-6613.
Sincere y,
A*4k�-
Mark J. ergam, .E., Senior Engineer
Engineering Review Section/Land Use Services Division