6826 176TH ST SW.PDFiiiiiiiiiiii
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6826 176TH ST SW
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DVE Consulting
DRAINAGE
REPORT
STREET FILE
HOVDE SHORT
PLAT
ML" A
PREPARED BY: Greg Krabbe, PE
CAMy Documents\DRN. REM99025clm.doc Last printed 09/16/99 9:08 AM
. I
DVE Consulting
E
I. INTRODUCTION
The subject development proposes the division of vroximately 0.45 Acres into 2single-
family lots. It is located along the south side of 176 street SW, just west of Olympic
View Dr..
In the existing condition the site is cleared with one existing single family residence. The
existing residence will not be figured into calculations.
Per the Snohomish County Soils Survey, the soils in this area are Alderwood, Hydrologic
soils group C.
11. DESIGN OVERVIEW AND STANDA"S
Runoff is to be collected and conveyed to an underground detention pipe located in the
central area of the site, under the proposed driveway. From detention, runoff shall be
discharged into the existing storm drainage system within 176th Street SW.
QF'FSITE RUNOFF
The subject site is located on a slight rise with topography sloping away on all sides.
Little or no runoff is anticipated to runoff onto the.site.
THE DEVELOPED CONDITION
The developed condition will simply increase the amount of impervious area on the site.
Impervious areas are as follows:
Roads
0.02 acres
Pond
0.00 acres
Lots
0. 18 acres.(4.000 sf / lot*
Total
0.20 acres @ CN 98
Most existing impervious area has been or will be demolished during new home
construction. The new home currently under construction has a roof plan of only
2,800 sf and the second is likely to be similar. An assumed value of 4,000 sf per lot
should be adequate to include the new homes and any impervious area from drives
and patios.
The balance of 0.25 acres will be evaluated @ CN 86.
Runoff ftom the site, Including roof drains, will be conveyed via yard drains and
underground pipes with in the yards.
CAMy Documents\DRN. REPT\99025dm.doc Last printed 09/16/99 9:03 AM
DVE Consulting
0
DETENTION AND RELEASE
Detention and release will be per DOE standards. Because runoff will ultimately be
discharged into the Puget Sound, discharge will be limited to maintain the existing
condition peak flows for the 2, 10 and 100 yr. events.
The total area being considered in this basin is approximately 0.45 Ac. As noted above,
the soil is of the hydrologic soils group C.
A 48" pipe was selected as the detention structure for this project. The length was.
determined to be 55'.
From Snohomish Co.. Isopluvials, intensities are as follows:
Intensities in total inches in 24 hr event are:
2 yr. 1.501,
10 yr. 2.00"
100 yr. 3.00"
The basins and hydrographs developed by the Waterworks software are attached to this
report.
The stage discharge calculations made with the Waterworks software predict a single
orifice discharge structure,%Nith a riser discharge to handle overflow. The orifice is to be
1.00" diameter at elevation 426.00' (2 feet below the outlet elevation). The 12" diameter
riser is to be at elevation 432.002. Please see Waterworks summary attached. .
Stage calculations show a high water stage for the 100 year event at 432.02', providing a
total detention volume of,- 683 cf.
DOWNSTREAM ANALYSIS
Discharge from the proposed detention structure will flow directly into an existing catch
basin along the southern side of 176h Street SW.
CAMy Documents\DRN. REM99025dm.doc Last printed 09/16/99 9:06 AM
.9/16/99 Hardt Engineering page
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
1ST SUBMITTAL
BASIN SUMMARY
BASIN ID: Al NAME: 6 MO EX
SBUH METHODOLOGY
TOTAL AREA ....... : 0.45 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE .... : TYPEIA PERVIOUS AREA
PRECIPITATION .... : 0.99 inches AREA..: 0.45 Acres
TIME INTERVAL .... : 10.00 min CN.... : 86.00
TIME OF CONC ..... : 22.21 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0.20 AREA..: 0.00 Acres
CN .... : 98.00
TcReach - Sheet L: 125.00 ns:0.1500 p2yr: 1.55 s:0.0100
PEAK RATE: 0.01 cfs V.OL: 0.01 Ac-ft TIME: 540 min
BASIN ID: A2 NAME: 2 YR EX
SBUH METHODOLOGY
TOTAL AREA ....... 0.45 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE .... TYPEIA PERVIOUS AREA
PRECIPITATION .... 1.50 inches AREA..: 0.45 Acres
TIME INTERVAL .... 10.00 min CN .... : 86.00
TIME OF CONC ..... 22.21 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0.20 AREA..: 0.00 Acres
CN .... : 98.00
TcReach - Sheet L: 125.00 ns:0.1500 p2yr: 1.55 s:0.0100
PEAK RATE: 0.03 cfs VOL: 0.02 Ac-ft TIME: 490 min
BASIN ID: A3
NAME: 10 YR
EX
SBUH METHODOLOGY
TOTAL AREA ....... :
0.45 Acres
BASEFLOWS:
0.00
cfs
RAINFALL TYPE .... :
TYPEIA
PERVIOUS AREA
PRECIPITATION .... :
2.00 inches
AREA..:
0.45
Acres
TIME INTERVAL .... :
10.00 min
CN .... :
86.00
TIME OF CONC ..... :
22.21 min
IMPERVIOUS
AREA
ABSTRACTION COEFF:
0.20
AREA..:
0.00
Acres
CN .... :
98.00
TcReach - Sheet
L: 125.00 ns:0.1500
p2yr: 1.55
s:0.0100
PEAK RATE: 0.06
cfs VOL: 0.03
AC-ft TIME:
490
min
9/16/99 Hardt Engineering page 2
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
1ST SUBMITTAL
BASIN SUMMARY
BASIN ID: A4
NAME: 100 YR
EX
SBUH METHODOLOGY
TOTAL AREA ....... :
0.45 Acres
BASEFLOWS:
0.00 cfs
RAINFALL TYPE .... :
TYPEIA
PERVIOUS AREA
PRECIPITATION .... :
3.00 i�ches
AREA..:
0.45 Acres
TIME INTERVAL .... :
10.00 min
CN .... :
86.00
TIME OF CONC ..... :
22-21 min
IMPERVIOUS
AREA
ABSTRACTION COEFF:
0.20
AREA..:
0.00 Acres
CN .... :
98.00
TcReach - Sheet
L: 125-00 ns:0.1500 p2yr: 1.55
s:0.0100
PEAK RATE: 0.13
cfs VOL: 0.06
Ac-ft TIME:
480 min
BASIN ID: Bl
SBUH METHODOLOGY
TOTAL AREA ....... :
RAINFALL TYPE .... :
PRECIPITATION .... :
TIME INTERVAL .... :
TIME OF CONC ..... :
ABSTRACTION COEFF4
NAME: 6 MO DEV
0.45 Acres
TYPElA
BASEFLOWS: 0.00 cfs
PERVIOUS AREA
0.99 inches
AREA..:
0.25 Acres
10-00 min
CN .... :
86.00
10-00 min
IMPERVIOUS
AREA
0.20
AREA..:
0.20 Acres
CN .... : 98.00
PEAK RATE: 0.04 cfs VOL: 0.02 Ac-ft TIME: 480 min
BASIN ID: B2*
SBUH METHODOLOGY
TOTAL AREA .......
RAINFALL TYPE ....
PRECIPITATION ....
TIME INTERVAL ....
TIME OF CONC .....
ABSTRACTION COEFF:
NAME: 2 YR DEV
0.45 Acres
BASEFLOWS:
0.00 cfs
TYPEIA
PERVIOUS AREA
1.50 inches
AREA..:
0.25 Acres
10-00 min
CN .... :
86.00
10-00 min
IMPERVIOUS
AREA
0.20
AREA..:
0.20 Acres
CN .... : 98.00
PEAK RATE: 0.08 cfs VOL: 0.03 Ac-ft TIME: 480 min
9/16/99 Hardt Engineering page 3
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
1ST SUBMITTAL
BASIN SUMMARY
BASIN ID: B3 NAME: 10 YR DEV
SBUH METHODOLOGY
TOTAL AREA 0.45 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE .... TYPEIA PERVIOUS AREA
PRECIPITATION .... 2.00 inches AREA..: 0.25 Acres
TIME INTERVAL .... 10.00 min CN.... : 86.00
TIME OF CONC ..... 10.00 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0.20 AREA..: 0.20 Acres
CN .... 98.00
PEAK RATE: 0.12 cfs VOL: 0.05 Ac-ft TIME: 480 min
BASIN ID: B4 NAME: 100 YR DEV
SBUH METHODOLOGY
TOTAL AREA .......
0.45 Acres
BASEFLOWS:
0.00 cfs
RAINFALL TYPE ....
TYPElA
PERVIOUS AREA
PRECIPITATION ....
3.00 inches
AREA..:
0.25 Acres
TIME INTERVAL ....
10.00 min
CN .... :
86.00
TIME OF CONC .....
10.00 min
IMPERVIOUS
AREA
ABSTRACTION COEFF:
0.20
AREA..:
0.20 Acres
CN .... :
98.00
PEAK RATE: 0.21
cfs VOL: 0.08
Ac-ft TIME:
480 min
9/16/99 Hardt Engineering pa . ge 4
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
1ST SUBMITTAL
HYDROGRAPH SUMMARY
PEAK
TIME
VOLUME
HYD
RUNOFF
OF
OF
Contrib
NUM
RATE
PEAK
HYDRO
Area
cfs
min.
cf\AcFt
Acres
1
0.006
540
315 cf
0. 45
2
0.029
490
804 cf
0.45
7-
Z-x
3
0.058
490
1387 cf
0.45
4
0.129
480
2716 cf
0.45
5
0.039
480
742 cf
0.45
6
0.077
480
1376 cf
0.45
-j7
7
0.118
480
2059 cf
0.45
8
0.207
480
3518 cf
0.45
1 c><�,,
18
0.031
560
1376 cf
0. 45
Z,
19
0.040
570
2060 cf
0.45
1
20
0.119
520
3519 cf
0.45
j
9/16/99 Hardt Engineering page 5
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
IST SUBMITTAL
STORAGE STRUCTURE LIST
UNDERGROUND PIPE ID No. 1
Description: DET. PIPE
Diameter: 4.00 ft. Length:
Slope ... : 0.0050 ft/ft
55.00 ft.
9/16/99 Hardt Engineering page 6
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
IST SUBMITTAL
DISCHARGE STRUCTURE LIST
MULTIPLE ORIFICE ID No. 1
Description:
Outlet Elev: 428.00
Elev: 426.00 ft Orifice Diameter:
RISER DISCHARGE ID No. 2
Description: RISER
Riser Diameter (in): 12.00 elev:
Weir Coefficient ... : 3 * .782 height:
Orif Coefficient ... : -9.739 increm:
COMBINATION DISCHARGE ID No. 3
Description:
Structure: I Structure:
Structure: 2 Structure:
Structure:
1 . 0000 in.
432.00 ft
433.00 ft
0. 10 ft
9 /16/99 Hardt Engineerin page 7
HOVDE SHORT P
DETENTION CALCUALTIONS LAI*
IST SUBMITTAL
LEVEL POOL TABLE SUMMARY
-------- DESCRIPTION --------- > MATCH INFLOW -STO- -DIS- (-PEAK-> STORAGE
(cfs) (cfs) (-STAGE> A VOL (cf)
------------- __
2 YR ......................... -------------
10 YR ........................ 0.03 0,08 1 3 429. 27 IS 161.03
0.06 0.12 1 3 430.06 19 328,30
100 YR ....................... 0.13 0,21 1 3 432.02 20 682.40
NOTICE:
No warranty of accuracy.
The information shown on the attached map(s)
was compiled for use by the City of Edmonds,
its Employees and Consultants. The City of
Edmonds does not warrant the accuracy of
anything set forth on these map(s). Any person
or entity requesting a copy should conduct an
independent inquiry regarding the information
shown on the map(s), including, but not limited
to, the location of any sewer stub shown. Such
sewer stubs may or may not exist and may or
may not exist at the location shown. Neither
the City of Edmonds nor its employees or
officers shall be liable for the information given
on map(s), nor for any one representation
provided based upon said map(s).
Water Service Drawing
The City of Edmonds
EASEMENT NO . ................................. .....
NEW CONSTRUCTION 19 REPAIRS El LID NO . .................. . ASMT. NO. ..- .............
OWNER................................. ... . ........................... ...................... CONTRACTOR ...... cx�.. . ................................... ........... PERIAIT
4
JOB ADDRESS .0 . ..... %+
LEGAL DESCRIPTION: LOT NO . .... ................................. BLOCK NO . .......................... ........
r
................................... I ........................... ....... I ....................... ................................................... I
NAMEOF ADDITION ...................... ..................................
4
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Approved: Yor�-&N
[jVM-00Ul-1 1175 JREV.11 1178) DATE ... 1-1-7.771-P-P ................... By ..... 4.D .......................................
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�10 pq-�-15
QTY OF EDMONDS SIDE SEWER PE*RMIT
/8 9 0 1 9 ;iZ, PERMIT �ii,,10 9160
Address of Construction:
782LP
Property Legal Description (include all easements):
EYNN _�
�_ WOOD'
Owner and/or Contractor: b, 13
State License No. Building Permit No.
Single Family
Multi -Family (No. of Units-)
Invasion into City Right-of-WayreNo 0 Yes
RW Construction Permit No.
El Commercial Cross other Private Property.eq No 0 Yes
Al
Public Attach legal description and copy of recorded easement
Z
i�lc`erfify that I have read and shall comply with all city requirements Date
as indicated on the back of the Permit Card.
* CALL DIAL-A-DIG.(1�800-424-5555) BEFORE ANY EXCAVATION *
OFFIICE%� U�E�.bNLY
FOR INSPECTION CALL 771-02ft-,Plul Ic WORKS DEPT.
Permit Fee: Issued =By <-� oz) �s
Trunk Charge: Date Issued: S-f?_:�Ao-
Assessment Fee- Receipt No.:
L i d N o.:
Partial Inspection: Date -Initial
Comments
Reason Rejected: Date Initial
Final I I nspection Approved: . Date T- ZS--(,Y) Initial /,_�o
7T
** PERMIT MUST BE POSTED ON JOB SITE **
White Copy: File Green Copy: Inspector Buff Copy: Applicant
Revised 3'90
of
The City of Edmonds
OWNER ....
JOB ADDRE�
Side Sewer Drawlng
EASEMENT NO . ................... .......................
NEW CONSTRUCTION REPAIRS LID NO . .................. ASMT. NO . ..................
Jar!, .............................. CONTRACTOR ... ...
K - -- ----------------- .............................. PERMIT NO. qj..(20
S .("?a . ..... S. .. .................. LEGAL DESCRIPTION: LOT NO . ...................................... BLOCK NO . ....................................
..................................................................................................................................................................
NAMEOF ADDITION .......................................................................................................................
C) u 'S 1�1
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PWW-0001-11/75 (REV.11/78)
Approved:
DATE ................. By
�TE RECEIVE&�,
PERMIT EXPIRES
CITY -OF EDMONDS
USE
ZON E 0 PERMIT 21DO�
NUMBER
CONSTRUCTIC-)N-PERMIT.APPLICATIO.N
JOB SUITEIAPT#
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ADDRESS
b 67-Le 1 -1 L-, Svj
OWNER,,NAME/NAME OF BUSINESS.
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PLAT NAME/SUBDIVISION NO.
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LID NO.
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LID FEE $
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PUBLIC RIGHT OF WAY PER OFFICIAL STREET MAP
TIES P Appmvedr
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EXISTING PROPO =D
StrOOt USS Pe—ft Req'd
Inspection Required
CITY ZIP
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Sid"alk Required
olp-r/oWD> qboso
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REQUIRED DEDICATION— FT
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REMARKS
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INSPECTION
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PROPERTY TAX ACCOUNT PARCEL NO.
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REQUIRED SETBACKS (FT)
PROPOSED SETBACKS (FT.)
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FRONT SIDE, REAR
FRONT URSIDE REAR
F1 ADDITION COMMERCIAL 0 COMPLIANCE OR
CHANGE OF USE
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(TYPE dF USE, BUSINESS OR ACTIVITY) EXPLAIN:
CHECKEDS
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GROUP
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CRITICAL
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STORIES
UNITS
NUMBER
REQUIRED C] 10K
YES
DESCRIBE WORK TO BE DONE
REMARKS
PROGRESS INSPECTIONS PER UBC 1081FINAL INSPECTION REO'D
-AQ 1� A/
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VALUATION
FEE
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HEAT SOURCE GLAZING LOT PLOPE
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0
MECHANICAL
THIS PERMIT AUTHORIZES ONLY THE WORK NOTED. THIS PERMIT COVERS WORK TO 90 M
t BE DONE ON PRIVATE PROPERTY ONLY. ANY CONSTRUCTION ON THE PUBLIC
DOMAIN (CURBS, SIDEWALKS, DRIVEWAYS, MARQUEES, ETC.) WILL REQUIRE GRADING/FILL
If
t SEPARATE PERMISSION.
cr STATE SURCHARGE
uj PERMIT -APPLICATION: 180 DAYS
PERMIT LIMIT. 1 YEAR - PROVIDED WORK IS STARTED. WITHIN 180 DAY,�S ENG.R EVIEW FEES
SEE BACK OF PINK PERMIT FOR MORE INFORMATION
NG I NS P
'APPLICANT. ON BEHALF OF HIS OR HER SPOUSE, HEIRS, ASSIGNS AND SUCCESORS ENG. INSPECTION FEE
N S A N D S U C C E S 0 R S
Uj IN INTEREST. AGREES TO INDEMNIFY, DEFEND AND HOLD HARMLESS THE CITY OF
_j I M L E S S T H E C IT Y 0 F
2 EDMONDS. WASHINGTON, ITS OFFICIALS, EMPLOYEES, AND AGENTS FROM ANY AND
cc N T S F R 0 M A N Y A N D
S',
ALL CLAIMS FOR DAMAGES OF WHATEVER NATURE, ARISING DIRECTLY OR INDIRECTLY U
% C T L Y 0 R I N D I R EC T LY
FROM THE ISSUANCE OF THIS PERMIT. ISSUANCE OF THIS PERMIT SHALL NOT BE F19CEIPT y 4
R M T S H ALL N OT 8 E LA N E
PLAN CHECK DE1
CH
DEEMED TO MODIFY, WAIVE OR REDUCE ANY REQUIREMENT OF ANY CITY ORDINANCE
N Y IT
k Y ORD NAN
C I C E
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I N A N CE PROV ISIO
OVISION.*
01 NOR LIMIT IN ANYWAY THE CITY'S ABILITY TO ENFORCE ANY ORDINANCE PR N
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RECEIPT
OT AL AM
TOTAL AMOUNT DUE
I HEREBY ACKNOWLEDGE THAT I HAVE READ THIS APPLICATION; THAT THE INFORMATION
AT THE NFOR
I MAT 10 N
THORZED AGENT OF
GIVEN IS CORRECTAND THAT I AM THE OWNER, OR THE DULY AUTHORIZED AGENT OF APPLICATION OPROVAL
THE OWNER. I AGREE TO COMPLY WITH CITY AND STATE LAWS REGULATING CONSTRUC- This application is not a permit until signed by the
,U LATI NG CON STRUC_ C
TION; CALL
AND IN DOING THE WORK AUTHORIZED THEREBY, NO PERSON WILL BE EMPLOYED
N WI LL BE EMPLOYED Building Official or his/her Deputy: and Fees are paid. and
IN VIOLATION OF THE LABOR CODE OF THE STATE OF WASHINGTON RELATING TO FOR INSPECTION receipt is acknowledged in space provided.
GTON 'ELATING To FOR IN
WORKMEN'S COMPENSATION INSURANCE AND RCW 18.27.
0 RE DATE
�FICTjd10IGN fta
SIGNA;URE (OWNER OR A DATE SIGNED/,
(425)
2
j 771
771-0220 _REdAS
E7 BY DA
A17ENTION EXT 333
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IT IS UNLAWFUL TO USE OR OCCUPY A BUILDING OR STRUCTURE UNTIL ..
771-0221 ' �b
I/
A FINAL INSPECTION HAS BEEN MADE AND APPROVAL OR A CERTIFI-
CATE OF OCCUPANCY HAS BEEN GRANTED. UBC SECTION 109 ORIGINAL - FILE YELLOW - INJECTOR
FAX
PINK - OWNER GOLD - ASSESSOR
5/98
PLANNImn DATA
N A M E:
SITE ADDRESS: -
ZONING: �PLAN CHK#:
PROJECT DESCRIPTION: kw,(-) SPf—
CORNER LOT--_41__.(Yes/No) FLAG LOT
(Yes/No)
SETBACKS:
Required Setbacks:
Front:-1,4- Left Slde:--Z�LRIght Side: Rear:
.Actual Setbacks:
Front:-Z:!!Z Left Side:-ZLLRight Slde:-ZZ�LRear:_.O�
Street map checked for additional setback required? (Yes/No)
LEGAL NONCONFORMING LAND USE DETERMINATION ISSUED (Y/N)
LOT COVERAGE:
Maximum Allowed:-6-5 �0����Actual: 1(�,,
BUILDING HEIGHT:
Maximum Allowed:
Actual Height:
Datum Point:
Datum Elevation:
A.D.U. CREATED?:
SUBDIVISION:
CRITICAL AREAS
SEPA DETERMINATION:
LOT
OTHER:
Plan Review By
c%fi16j%penWt%Apjand&Ldoo
DVE Consulting 0
0
DRAINAGE
REPORT
HOVDE SHORT
PLAT
C7
PREPARED BY: Greg Krabbe, PE
1 411(0117
CAMy Documents\DRN. REPT\99025dm.doc Last printed 09/16/99 9:08 AM
DVE Consulting
I. INTRODUCTION
The subject development proposes the division of a proximately 0.45 Acres into 2single-
family lots. It is located along the south side of 1769 street SW, just west of Olympic
View Dr..
In the existing condition the site is cleared with one existing single family residence —The
existing residence will not be figured into calculations.
Per the Snohomish County S I oils Survey, the soils in this area are Alderwood, Hydrologic
soils group C.
11. DESIGN OVERVIEW AND STANDA"S
Runoff is to be collected and conveyed to an underground detention pipe located in the
central area of the site, under the proposed driveway. From detention, runoff shall be
discharged into the existing storm drainage system within 176h Street SW.
OFFSTTE RUNOFF
The subject site is located on a slight rise with topography sloping away on all sides.
Little or no runoff is anticipated to runoff onto the site.
THE DEVELOPED CONDITION
The developed condition will simply increase the amount of impervious area on the site.
Impervious areas are as follows:
Roads 0.02 acres
Pond 0.00 acres
Lots 0. 18 acres (4.000 sf / lot*)
Total 0.20 acres @ CN 98
Most existing impervious area has been or will be demolished during new home
construction. The new home currently under construction has a roof plan of only
2,800 sf and the second is likely to be similar. An assumed value of 4,000 sf per lot
should be adequate to include the new homes and any impervious area from drives
and patios.
The balance of 0.25 acres,-Arill be evaluated @ CN 86.
Runoff from the site, including roof drains, will be conveyed via yard drains and
underground pipes with in the yards.
CAMy Documents\DRN. REPT\99025dm.doc Last printed 09/16/99 9:03 AM
DVE Consulting 0
DETENTION AND RELEASE
Detention and release will be per DOE standards. Because runoff will ultimately be
discharged into the Puget Sound, discharge will.be limited to maintain the existing
condition peak flows for the 2, 10 and 100 yr. events.
The total area being considered in this basin is approximately 0.45 Ac. As noted above,
the soil is of the hydrologic soils group C.
A 48" pipe was selected as the detention structure for this,project. The length was
determined to be 55'.
From Snohomish Co. Isopluvials, intensities are as follows:
Intensities in total inches in 24 hr event are:
2 yr. 1.50"
10 yr. 2.00"
100 yr. 3.00"
The basins and hydrographs developed by the Waterworks software are attached to this
report.
The stage discharge calculations made with the Waterworks software predict a single
orifice discharge structure with a riser -discharge to handle overflow. The orifice is to be
1.00" diameter at elevation 426.00' (2 feet below the outlet elevation). The 12" diameter
riser is to be at elevation 432.00'. Please see Waterworks summary attached. .
Stage calculations show a high water stage for the 100 year event at 432.02', providing a
total detention volume of, 683 eL
DOWNSTREAM ANALYSIS
Discharge from the proposed detention structure will flow directly into an existing catch
basin along the southern side of 176h Street SW.
CAMy Documents\DRN. REM99025dm.doc Last printed 09/16/99 9:06 AM
-9/16/99 Hardt Engineering page
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
IST SUBMITTAL
BASIN SUMMARY
BASIN ID: Al NAME: 6 MO EX
SBUH METHODOLOGY
TOTAL AREA ....... : 0.45 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE .... : TYPEIA PERVIOUS AREA
PRECIPITATION .... : 0.99 inches AREA.. 0.45 Acres
TIME INTERVAL .... : 10.00 min CN.... 86.00
TIME OF CONC ..... : 22.21 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0.20 AREA..: 0.00 Acres
CN .... : 98.00
TcReach - Sheet L: 125.00 ns:0.1500 p2yr: 1.55 s:0.0100
PEAK RATE: 0.01 cfs V.OL: 0.01 Ac-ft TIME: 540 min
BASIN ID: A2
NAME: 2 YR EX
SBUH METHODOLOGY
TOTAL AREA .......
0.45 Acres
BASEFLOWS:
0.00
cfs
RAINFALL TYPE ....
TYPElA
PERVIOUS AREA
PRECIPITATION ....
1.50 inches
AREA..:
.0.45
Acres
TIME INTERVAL ....
10.00 min
CN .... :
86.00
TIME OF CONC .....
22.21 min
IMPERVIOUS
AREA
ABSTRACTION COEFF:
0.20
AREA..:
0.00
Acres
CN .... :
98.00
TcReach - Sheet
L: 125.00 ns:O..1500
p2yr: 1.55
s:0.0100
PEAK RATE: 0.03
cfs VOL: 0.02
Ac-ft TIME:
490
min
BASIN ID: A3 NAME: 10 YR EX
SBUH METHODOLOGY
TOTAL AREA ....... : 0.45 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE .... : TYPEIA PERVIOUS AREA
PRECIPITATION .... : 2.00 inches AREA..: 0.45 Acres
TIME INTERVAL .... : 10.00 min CN.... : 86.00
TIME OF CONC ..... : 22.21 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0.20 AREA..: 0.00 Acres
CN.... : 98.00
TcReach - Sheet L: 125.00 ns:0.1500 p2yr: 1.55 s:0.0100
PEAK RATE: 0.06 cfs VOL: 0.03 Ac-ft TIME: 490 min
9/16/99 Hardt Engineering
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
1ST SUBMITTAL
BASIN SUMMARY
page 2
BASIN ID: A4
NAME: 100 YR
EX
SBUH METHODOLOGY
TOTAL AREA ....... :
0.45 Acres
BASEFLOWS:
0.00 cfs
RAINFALL TYPE .... :
TYPElA
PERVIOUS AREA
PRECIPITATION .... :
3.00 inches
AREA..:
0.45 Acres
TIME INTERVAL .... :
10.00 min
CN.....:
86.00
TIME OF CONC ..... :
22.21 min
IMPERVIOUS
AREA
ABSTRACTION COEFF:
0.20
AREA..:
0.00 Acres
CN ....
98.00
TcReach - Sheet
L: 125-00 ns:0.1500 p2yr: 1.55
s:0.0100
PEAK RATE: 0.13
cfs VOL: 0.06
Ac-ft TIME:
480 min
BASIN ID: BI
SBUH METHODOLOGY
TOTAL AREA ....... :
RAINFALL TYPE .... :
PRECIPITATION .... :
TIME INTERVAL .... :
TIME OF CONC ..... :
ABSTRACTION COEFF:
NAME: 6 MO DEV
0.45 Acres
TYPElA
BASEFLOWS: 0.00 cfs
PERVIOUS AREA 1Z
0.99 inches
AREA..:
0.25 Acres
10.00 min
CN .... :
86.00
10.00 min
IMPERVIOUS
AREA
0.20
AREA...:
0.20 Acres
CN .... : 98.00
PEAK RATE: 0.04 cfs VOL: 0.02 Ac-ft TIME: 480 min
BASIN ID: B2
SBUH METHODOLOGY
TOTAL AREA ....... :
RAINFALL TYPE .... :
PRECIPITATION .... :
TIME INTERVAL .... :
TIME OF CONC ..... :
ABSTRACTION COEFF:
NAME: 2 YR DEV
0.45 Acres
BASEFLOWS:
0.00 cfs
TYPEIA
PERVIOUS AREA
1.50 inches
AREA..:
0.25 Acres
10-00 min
CN .... :
86.00
10.00 min
IMPERVIOUS
AREA
0.20
AREA..:
0.20 Acres
CN .... : 98.00
PEAK RATE: 0.08 cfs VOL: 0.03 AC-ft TIME: 480 min
9/16/99 Hardt Engineering page 3
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
IST SUBMITTAL
BASIN SUMMARY
BASIN ID: B3 NAME: 10 YR DEV
SBUH METHODOLOGY
TOTAL AREA ....... : 0.45 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE .... : TYPElA PERVIOUS AREA
�PRECIPITAT.ION .... : 2.00 inches AREA..: 0.25 Acres
TIME INTERVAL .... : 10.00 min CN.... : 86.00
TIME OF CONC.—.: 10.00 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0.20 AREA..: 0.20 Acres
CN .... : 98.00
PEAK RATE: 0.12 cfs VOL: 0.05 Ac-ft TIME: 480 min
BASIN ID: B4
SBUH METHODOLOGY
TOTAL AREA ....... :
RAINFALL TYPE., ... :
PRECIPITATION .... :
TIME INTERVAL ....
TIME OF CONC .....
ABSTRACTION COEFF:
NAME: 100 YR DEV
0.45 Acres
BASEFLOWS:
0.00 cfs
TYPEIA
PERVIOUS AREA
3.00 inches
AREA..:
0.25 Acres
10.00 min
CN .... :
86.00
10.00 min
IMPERVIOUS
AREA
0.20
AREA..:
0.20 Acres
CN .... : 98.00
PEAK RATE: 0.21 cfs VOL: 0.08 Ac-ft TIME: 480 min
9/16/99 Hardt Engineering page 4
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
1ST SUBMITTAL
HYDROGRAPH SUMMARY
PEAK
TIME
VOLUME
HYD
RUNOFF
OF
OF
Contrib
NUM
RATE
PEAK
HYDRO
Area
cfs
min.
cf\AcFt
Acres
1
0.006
540
315 cf
0. 45
2
0.029
490
804 cf
0.45
7-
3
0.058
490
1387 cf
0.45
tc>
4
0.129
480
2716 cf
0.45
c�,z,
5
0.039
480
742 cf
0.45
6
0.077
480
1376 cf
0.45
j7
7
0.118
480
2059 cf
0.45
8
0.207
480
3518 cf
0.45
c>'E-�,
18
0.031
560
1376 cf
0. 45
Z-
19
0.040
570
2060 cf
0.45
1 --n-
20
0.119
520
3519 cf
0.45
1 C
a
a
9/16/99 Hardt Engineering page 5
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
1ST SUBMITTAL
STORAGE STRUCTURE LIST
UNDERGROUND PIPE ID No. I
Description: DET. PIPE
Diameter: 4.00 ft. Length:
Slope...: 0.0050 ft/ft
55.00 ft.
9/16/99 Hardt Engineering page 6
HOVDE SHORT PLAT
DETENTION CALCUALTIONS
1ST SUBMITTAL
DISCHARGE STRUCTURE LIST
MULTIPLE ORIFICE ID No. I
Description:
Outlet Elev: 428.00
Elev: 426.00 ft Orifice Diameter:
RISER DISCHARGE ID, No. 2
Description: RISER
Riser Diameter (in): 12.00 elev:
Weir Coefficient ... : 3.782 height:
Orif Coefficient ... : -9.739 increm:
COMBINATION DISCHARGE ID, No. 3
Description:
Structure: I Structure:
Structure: 2 Structure:
Structure:
1.0000 in.
432.00 ft
433.00 ft
0.10 ft
9/16/99
Hardt Engineerin page 7
HOVDE SHORT PLAID
DETENTION CALCUALTIONS T
IST SUBMITTAL
LEVEL POOL TABLE SUMMARY
MATCH INFLOW -STO- -DIS- �-PEAK-� STORAGE
-------- DESCRIPTION --------- > (cfs) (cfs) (-STAGE> id VOL (cf)
2 YR ......................... 0.03 0.08 3 429'.27 IS 161.03
10 YR ........................ 0.06 0.12 3 430.06 19 328,30
100 YR ....................... 0.13 0.21 3 432-02 20 682.40
0-
b-
,i:z
ELE R�SER
3ER- A?,
440
mIfo,-
(C
I
A PORTION OF SECTION 5, TOWNSHIP 27 NORTH, RANGE 4 EAST, WILLAMETTE MERIDIAN, CITY OF EDMONDS, WA
MAKE CONNECTION TO EX. CB CB - 3 (TYPE I
STA -0+61.19 (13.61' RT) STA 0+62.79 (11'RT)
EX. PP EX. MAILBOXES
RIM =428.82 RIM =432.23 PV1 STA = 0+65
INV=425. 10 1,11J'V= 42 Z 70 TO BE RELOCTAED TO BE RELOCTAff
PW ELEV = 435.06-
SEWER MANHOLE NO. 177 SEWER MANHOLE NO. 178
RIM=432.24' RIM 430 72
INVERT ELEV=423.67' TELE RISER 1INZT �iEV=420.97
EILO_ CITY OF EDMONDS DAnJM
X
1,E RISERA
0_
I 176TH ST EET S. W
�41co " I I 8,,_ckNC SE L11
"NJ SEWER LINE
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w DI
TELk`., IR'S''El)
C)
j�' 6 2 O8X
5:117
DIW`
" v 3. TAPER
"STOP SIGN - M
AHEAD" SIGN,-,
30 F )R 0. 1.
WATER SERWCE-,-' CL TRU.b T TEMP.
dill TO BE RELOCA A PHA
AS LV RAMP.'
C0NSj,RU,CT 7EY n 1 W-APPLE
ASPHAL'T RA
A 11
IT LL
'J. �"qb'
SAN R Y \6ERWC
h.
LER
, W
X, \INSTALL NEW DOMESTI ffR-
\ EXCONC. SIDEWA W�TER SERWCE AND I
YARD DRAIN�TYP) SD� @ 0.50Z
pip,
A
DE
25' B. S. B. L.
j -------- - --- ------------ -- ------------------
r 7-
00
>1
12 CB 2 (T'yp YARD DRAIN(TYP)
2 CONTROL STRUC
06
STA 0+36
Q) RIM =433.80
LOT 2
vo c INV=428.00 c(i
9,151 SF (GROSS) CQ
i vi
8,675 SF (NET) \ i I
0
CB I 6TYPE 11 48") to
0+,q�
2 EX. CONC. SID LK _,--�STA
RIM =4.35.�4
),i VIEW RIDGE 1\10,
INV1:428.22\ H
C6 1
vil ,OT
9,517 SF Oss)
9,041 SF 5' ESM T \ACCESS
T) FOR LOT I
48" CEDAR
L 5' ESMT. ACCESS
FOR LOT 2
0" APPLE GRAPHIC SCALE
L--------- ------------------------------------------ j t ----------------------- 20 0 10 20 40
15' El. S. 8. L.
QTQI� W-1,114 DO -ace IN FEET
I INCH 20 FT
L71NE OF 6" FIRE TREES
VIEW RIDGE 1\1 0. 6 5
V. 37, PG, 29
PV1 STA = 0+15.85
PV1 ELEV = 432.00
A.D. -2.94
K 17 02
50. 00** VC
HIGH POINT ELEV = 432.63
HIGH POINT STA = 0+71.26
PVI STA 1+10
PV1 ELEV 433.20
A.D. = -11.32
K = 8.84
I uu. uu v(;
Q) V-
to
Lo
(3)
c;
ca cn
PROPOSED
GRADE
oi _p
EXI�
77NG GRADE CQ
EX. CB
STA -0+61.19
RIM = 428.82
INV = 425.10
Ar.
�qn @
f sD
LF
CB - 3 (TYPE I)
1195
2
STA 0+62.79
RIM = 432.23
INV= 42Z 70
DATUM ELEV
425.00
C)
n
0)
C*\j
CN
CN
V-
_1+00
0+00
176TH STREET SW ROAD PROFILE
SCALE: 1"--20' HOR, 1"=2' VERT
1+00
I
MO.-
440
430
CN
CL
A. D. - 4.08
K 6. 13
25. 00' VC
r<
LLJ to
UCN)
N
+
Lr)
Q)
LLJ
Lu
ca
EXISTING GRADEE
PROPOSED GRAD
JO LF 12" SD
@ 1. 00%
CB - i
STA 0+11
RIM = 432.2J
INV= 42 7.70
,8 - 2 (TYPE 11, -.554)
TA 0+36
IM = 433.80
4 V = 428. 00
Lo
N
Poo
SIDEWALK
R
p
100 YR WSE 432.02
55 � LF 48" SD @ 0. 507.
DETENTION PIPE
CB - 1 (TYPE //, 48')
STA 0+96
RIM = 435.14
INV---428.-75--
Lo
1+00
ACCESS ROAD PROFILE
SCALE. 1"=20' HOR., 1"=2' VERT.
JO,
7-± .
NEW 5'-± EX. _L2
2% ASPHALT ASPHALT
/-r-\ - 2%
20' R,
2" COMP. DEPTH CL. "B" ASPH. CONC.
3" COMP. DEPTH A T13
6" COMP. DEPTH GRAVEL BORROW
10 YR WSE 4t3O.O6
2 YR WSE 429.27
176TH STREET SW, FRONTAGE SECTION C-C
N. T. S.
NOTE: PAYMENT IN LIEW OF FRONTAGE CONSTRUCTION
AUTHORIZED ON 9113199
CITY OF EDMONDS
APPROVED FOR CONSTRUCTION
BY Ago,
V CITY ENGINEER DA
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