1999-5992 G Street Address
65 - 0 1 l
Category Serial #
Name Description
Plan ck. # Year
<.
Ci O�INEERING SERVICES DEPARTMENT
Encinitas Capital Improvement Projects
District Support Services
Field Operations
Sand Replenishment/Stormwater Compliance
Subdivision Engineering
Traffic Engineering
January 16, 2003
Attn: California Bank and Trust
135 Saxony Road
Encinitas, California 92024
RE: Ardecky, Robert and Janice
3461 Calle Margarita
APN 264 - 241 -12
Grading Permit 5992 -G
Final release of security
Permit 5992 -GI authorized earthwork, storm drainage, site retaining wall, and erosion
control, all as necessary to build the described project. The Field Inspector has finaled the
project. Therefore, a full release of the security deposited is merited.
Certificate of Deposit 356020277, in the remaining amount of $7,407.25, is hereby
released in its entirety. The document original is enclosed. The CD number was the one
on the Eldorado Bank document.
Should you have any questions or concerns, please contact Debra Geishart at (760) 633-
2779 or in writing, attention this Department.
Sincerely,
Masih Maher A JTayLe
mbac
Senior Civil Engineer Finance Manager
Field Operations Financial Services
CC: Jay Lembach, Finance Manager
Ardecky, Robert and Janice
Debra Geishart
File
TEL 760- 633 -2600 / FAX 76o- 633 -2627 505 S. Vulcan Avenue, Encinitas, California 92024 -3633 TDD 760- 633 -2700 �� recycled paper
Tri- Dimensional En lnc _
E N G I N E E R S • P L A N N E R S S U R V E Y O S
HYDROLOGY /HYDRAULIC STUDY
Ardecky Residence
3461 Calle Margarita, Encinitas, CA
July 6, 1999
SITE CHARACTERISTICS /CURRENT CONDITIONS• The 2.93 acre site is located
in a low density residential subdivision in Olivenhain. Approximately two- thirds of the site
(eastern portion) is protected by a `protection of steep slopes' open space easement, and will
remain undisturbed by grading and development. The existing pad currently drains easterly into
the open space area and into a natural ravine. The existing 2:1 slopes near the street ( Calle
Margarita) drain to the street over the A. C. dike. Offsite flows enter the site on the north side
of the pad only (east, south, and west sides of the pad currently direct runoff away from the
site). Flows in the street from other properties remain in the street.
SUMMARY: Proposed is on -site grading of approximately 200 cubic yards of cut and
200 cy of fill (net balance) material for construction of a residence and driveway. In order to
preserve the slopes within the open space easement area, we propose diversion and collection of
runoff at the pad level, with delivery to the street. Flows from the pad and the roof, including
those off -site flows indicated on Drainage Map `B', excluding flows on the driveway
motorcourt, will be collected in an underground drainage system and concentrated at a curb
outlet at the southwest corner of the lot. Flows from the driveway motorcourt will remain on
the driveway and exit to the street. Driveway and curb outlet flows will continue southerly
along the asphalt berm to an existing 3'4 "x4' grate inlet approximately 300' southerly, set in an
inset of Calle Margarita. The adequacy of proposed on -site drainage structures will be analyzed
for 100 - year -storm conditions. See Drainage Map `A' for on -site drainage areas and flow cross
section locations. See Drainage Map `B' for off -site drainage areas contributing to flows on-
site.
FLOWS: The Rational Method was used to determine total flow quantity at time of
concentration for a 100- year -storm for each critical area (see Drainage Map `A' for areas)
ONSITE FLOWS
Onsite flows were analyzed to determine capacity of on -site drainage structures (see
Drainage Map `A' for areas).
Time of Concentration flow quantity for A.1:
4 tM�L 5 ' -1
J I
ENGINLEF ��G Srxi llCEs
CITY OF E NCINITAS
P.O. Box 791 • Poway, CA 92074 • (619) 748 -8333 • ax -
July 6, 1999
Page 2 of 9
C = 0.55 (County of San Diego Runoff Coefficients, Soil Type `D',
Use single- family residential, [see attached Runoff
Coefficients Table])
T = 10 min. (minimum used, small drainage areas)
I = 4.9 in/hr (See attached Rainfall Intensity - Duration - Frequency
worksheet and 6, 24 hour isopluvial charts for County of
San Diego, Duration equals 10 minutes, 100 year storm)
A = 0.17 acres
Q(A.1) = ( 0.55) *(4.9) *(0.17)
Q(A.1) = 0.46 CFS, the expected flow rate for a 100 - year -storm with a 10 minute
(time of concentration) duration at this location of the site.
Time of Concentration flow quantity for A.2:
Q(A.2) = C * I * A
C = 0.55 (County of San Diego Runoff Coefficients, Soil Type `D',
Single family residential lot [see attached Runoff
Coefficients Table])
T = 10 min. (minimum used, small drainage areas)
I = 4.9 in /hr (See attached Rainfall Intensity - Duration- Frequency
worksheet and 6, 24 hour isopluvial charts for County of
San Diego, Duration equals 10 minutes, 100 year storm)
A = 0.26 acres
Q(A.2) = ( 0.55) *(4.9) *(0.26)
Q(A.2) = 0.70 CFS, the expected flow rate for a 100 - year -storm with a 10 minute
(time of concentration) duration at this location of the site.
Time of Concentration flow quantity for A.3:
July 6, 1999
Page 3 of 9
Q(A.3)100 = C * I * A
C = 0.55 (County of San Diego Runoff Coefficients, Soil Type `D',
Single family residential lot [see attached Runoff
Coefficients Table])
T = 10 min. (minimum used, small drainage areas)
I = 4.9 in/hr (See attached Rainfall Intensity - Duration- Frequency
worksheet and 6, 24 hour isopluvial charts for County of
San Diego, Duration equals 10 minutes, 100 year storm)
A = 0.07 acres
Q(A.3) = ( 0.55) *(4.9) *(0.07)
Q(A.3) = 0.19 CFS, the expected flow rate for a 100 - year -storm with a 10 minute
(time of concentration) duration at this location of the site.
Time of Concentration flow quantity for AA
Q(A.4),. = C * I * A
C = 0.55 (County of San Diego Runoff Coefficients, Soil Type `D',
Single family residential lot [see attached Runoff
Coefficients Table])
T = 10 min. (minimum used, small drainage areas)
I = 4.9 in/hr (See attached Rainfall Intensity - Duration - Frequency
worksheet and 6, 24 hour isopluvial charts for County of
San Diego, Duration equals 10 minutes, 100 year storm)
A = 0.19 acres
Q(A.4) = ( 0.55) *(4.9) *(0.19)
Q(A.4) = 0.51 CFS, the expected flow rate for a 100 - year -storm with a 10 minute
(time of concentration) duration at this location of the site.
July 6, 1999
Page 4 of 9
Time of Concentration flow quantity for B.1:
Q(B. = C *I *A
C = 0.55 (County of San Diego Runoff Coefficients, Soil Type `D',
Single family residential lot [see attached Runoff
Coefficients Table])
T = 10 min. (minimum used, small drainage areas)
I = 4.9 in/hr (See attached Rainfall Intensity - Duration- Frequency
worksheet and 6, 24 hour isopluvial charts for County of
San Diego, Duration equals 10 minutes, 100 year storm)
A = 0.09 acres
Q(B.1) _ ( 0.55) *(4.9) *(0.09)
Q(B.1) = 0.24 CFS, the expected flow rate for a 100 - year -storm with a 10 minute
(time of concentration) duration at this location of the site.
OFFSITE FLOWS
Offsite flows were analyzed to determine their contribution to the drainage system (see
Drainage Map `B' for areas). Offsite flow areas X.1 and X.4 contribute to onsite flow areas
A.1 and A.4 respectively.
Time of Concentration flow quantity for X.1:
Q(X.1) = C * I * A
C = 0.55 (County of San Diego Runoff Coefficients, Soil Type `D',
Use single - family residential, [see attached Runoff
Coefficients Table])
T = 10 min. (minimum used, small drainage areas)
I = 4.9 in/hr (See attached Rainfall Intensity - Duration- Frequency
worksheet and 6, 24 hour isopluvial charts for County of
San Diego, Duration equals 10 minutes, 100 year storm)
July 6, 1999
Page 5 of 9
A = 0.06 acres
Q(X.1) = ( 0.55) *(4.9) *(0.06)
Q(X.1) = 0.16 CFS, the expected flow rate for a 100 - year -storm with a 10 minute
(time of concentration) duration at this location of the site.
Time of Concentration flow quantity for X.2:
Q(X.4) = C * I * A
C = 0.55 (County of San Diego Runoff Coefficients, Soil Type `D',
Use single - family residential, [see attached Runoff
Coefficients Table])
T = 10 min. (minimum used, small drainage areas)
I = 4.9 in/hr (See attached Rainfall Intensity - Duration - Frequency
worksheet and 6, 24 hour isopluvial charts for County of
San Diego, Duration equals 10 minutes, 100 year storm)
A = 0.08 acres
Q(X.4) = ( 0.55) *(4.9) *(0.08)
Q(X.4) = 0.22 CFS, the expected flow rate for a 100 - year -storm with a 10 minute
(time of concentration) duration at this location of the site.
July 6, 1999
Page 6 of 9
Summary of flows:
Q(A.1) = 0.46 CFS
Q(A.2) = 0.70 CFS
Q(A.3) = 0.19 CFS
Q(A.4) = 0.51 CFS
Q(B.1) = 0.24 CFS
Q(X.1) = 0.16 CFS
Q(X.4) = 0.22 CFS
July 6, 1999
Page 7 of 9
HYDRAULIC ANALYSIS: Flows were analyzed at sections considered critical,
specifically flows A.l +X.1 (PVC Line), A.1 +2 +X.1 (PVC Line), A.3 (PVC line), A.4 +X.4
(PVC line), A.1 +2 +3 +4 +X.1 +4 (PVC line and curb outlet), B.1 (driveway surface flow).
See drainage map `A' for flow cross section locations.
Where noted, the manning equation, as follows, was used to determine flow quantities
and sections of flow:
Q. = A * V, where
V = (1.49/n) * 1 111 * S vz
Flow Through PVC drain line, A.1 +X.1:
A computer program utilizing the manning equation was used to determine the flow cross
section at this location. Complete results appear on the attached data sheet.
Q(A.1 + X.1) = 0.62 cfs, S = 0.01
For this section, the flow would be at depth of 0.34', with a velocity of 3.48 fps -
use 8" PVC
Flow Through PVC drain line, A.1 +2 +X.1:
A computer program utilizing the manning equation was used to determine the flow cross
section at this location. Complete results appear on the attached data sheet.
Q(A.1 +2 +X.1) = 1.32 cfs, S = 0.032
For this section, the flow would be at depth of 0.38', with a velocity 6.50 fps - OK,
8" pipe adequate.
Flow Through PVC drain line, A.3:
A computer program utilizing the manning equation was used to determine the flow cross
section at this location. Complete results appear on the attached data sheet.
Q(A.3) = 0.19 cfs, S = 0.02
July 6, 1999
Page 8 of 9
For this section, the flow would be at depth of 0.21', with a velocity of 3.34 fps -
OK, 4 pipe adequate.
Flow Through PVC drain line, A.4 +X.4:
A computer program utilizing the manning equation was used to determine the flow cross
section at this location. Complete results appear on the attached data sheet.
Q(A.4 +X.4) = 0.73 cfs, S = 0.01
For this section, the flow would be at depth of 0.37', with a velocity of 3.62 fps -
OK, use 8" pvc 0 1% min.
Flow Through PVC drain line, A.1 +2 +3 +4 +X.1 +4:
A computer program utilizing the manning equation was used to determine the flow cross
section at this location. Complete results appear on the attached data sheet.
Q(A.1 +2 +3 +4 +X.1 +4) = 2.24 cfs, S = 0.187
For this section, the flow would be at depth of 0.30', with a velocity of 14.39 fps -
OK, pipe adequate.
Flow Through Curb Outlet, A.1 +2 +3 +4 +X.1 +4:
A computer program utilizing the manning equation was used to determine the flow cross
section at this location. Complete results appear on the attached data sheet.
Q(A.1 +2 +3 +4 +X.1 +4) = 2.24 cfs, S = 0.02
For this section, the flow would be at depth of 0.17', with a velocity of 4.53 fps, and
top width (constrained) of 3.0' - OK.
July 6, 1999
Page 9 of 9
Flow At Driveway Apron, B.1:
A computer program utilizing the manning equation was used to determine the flow cross
section at this location. Complete results appear on the attached data sheet.
Q(B.1) = 0.24 cfs, S = 0.10
For this section, the flow would be at depth of 0.04', with a velocity of 2.62 fps, and
top width of 4.37' — OK.
This report has been prepared and /or reviewed by the undersigned
7 -G g9
Ernest H. Grabbe, Jr. RCE 04732 Date
� Ox"
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SAN DIEGO COUNTY NOMOGRAPH FOR DETERMINATION
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DESIGN MANUAL FOR NATURAL WATERSHEDS
APPROVED _ '� �r�"'��+^ ct a� DATE n�� /6 9 APPENDIX x -A
LA-10 Rev. 5/81
RUNOFF COEFFICIENTS (RATIONAL METHOD)
L:L \D USE Coefficient, C
Soil Group 1'1)
A B C D
Undeveloped 5U 35 40 5
Residential:
Rural 30 J 10
Single Family .40 .45 .50 .55
Multi -Units .45 .50 .60 .70
Mobile Homes (2) .45 .50 .55 .55
Commercial (2) .70 .75 .80 .33
800 Impervious
Industrial (2) .80 .85 .90 ?5
90° Impervious
NOTES.
Cl) Obtain soil group from maps on file with the Department of Sanitation
and Flood Control.
(2) Where actual conditions deviate significantly from the tabulated
imperviousness values of 800 or 900, the values given for coefficient
C, may be revised by multiplying 800 or 900 by the ratio of actual
imperviousness to the tabulated imperviousness. However, in no case
shall the final coefficient be less than 0.50. For example: Cor.s: der
commercial property on D soil group.
Actual imperviousness = 500
Tabulated imperviousness = S00
Revised C = 50 X 0.85 = 0.55
APPENDI `:
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Revised 1 /8S APPENDIX XI -E
PROJECT: Flow A.1 +X.1 - 8" PVC @ 1 %r
DATE: 07 -06 -1999
PIPE FLOW TIME: 13:08:24
Diameter (inches) ... 8 Mannings n ....... .013
Slope (ft /ft) ....... 0.0100 Q (cfs) ........... 0.62
depth (ft) .......... 0.34 depth /diameter ... 0.51
Velocity (fps) ...... 3.48 Velocity head .... 0.19
Area (Sq. Ft.) ...... 0.18
Critical Depth ...... 0.37 Critical Slope ... 0.0074
Critical Velocity ... 3.11 Froude Number .... 1.19
PROJECT: Flow A.1 +2 +X.1
DATE: 07 -06 -1999
PIPE FLOW TIME: 13:09:42
Diameter (inches) ... 8 Mannings n 013
Slope (ft /ft) ....... 0.0320 Q (cfs) ........... 1.32
depth (ft) .......... 0.38 depth /diameter ... 0.56
Velocity (fps) ...... 6.50 Velocity head .... 0.66
Area (Sq. Ft.) ...... 0.20
Critical Depth ...... 0.54 Critical Slope ... 0.0121
Critical Velocity ... 4.34 Froude Number .... 2.06
J
PROJECT: FLOW A.3 - 4" PVC @ 2%
DATE: 04 -20 -1999
PIPE FLOW TIME: 10:36:08
Diameter (inches) ... 4 Mannings n 013
Slope (ft /ft) ....... 0.0200 Q (cfs) ........... 0.19
depth (ft) .......... 0.21 depth /diameter ... 0.62
Velocity (fps) ...... 3.34 Velocity head .... 0.17
Area (Sq. Ft.) ...... 0.06
Critical Depth ...... 0.25 Critical Slope 0.0125
Critical Velocity ... 2.75 Froude Number .... 1.40
PROJECT: Flow A.4 +X.4
DATE: 07 -06 -1999
PIPE FLOW TIME: 13:10:21
Diameter (inches) ... 8 Mannings n 013
Slope (ft /ft) ....... 0.0100 Q (cfs) ........... 0.73
depth (ft) .......... 0.37 depth /diameter ... 0.56
Velocity (fps) ...... 3.62 Velocity head .... 0.20
Area (Sq. Ft.) ...... 0.20
Critical Depth ...... 0.40 Critical Slope 0.0079
Critical Velocity ... 3.30 Froude Number .... 1.16
J
PROJECT: Flow A.1 +2 +3 +4 +X.1 +4 - 8 pvc @ 18.70
DATE: 07 -06 -1999
PIPE FLOW TIME: 13:16:02
Diameter (inches) ... 8 Mannings n 013
Slope (ft /ft) ....... 0.1870 Q (cfs) ........... 2.24
depth (ft) .......... 0.30 depth /diameter ... 0.46
Velocity (fps) ...... 14.39 Velocity head .... 3.22
Area (Sq. Ft.) ...... 0.16
Critical Depth ...... 0.64 Critical Slope 0.0299
Critical Velocity ... 6.51 Froude Number .... 5.24
PROJECT: Flow A.1 +2 +3 +4 +X.1 +4 - CURB OUTLET
DATE: 07 -06 -1999
RECTANGULAR CHANNEL TIME: 13:18:38
INVERT WIDTH (feet) ... 3.00 MANNINGS n ......... .013
SLOPE (feet /foot) ..... .0200 Q (cfs) ............ 2.24
LEFT SIDE RIGHT SIDE
SLOPE (X to 1) ........ 0.00 SLOPE (X to 1) ..... 0.00
DEPTH (feet) .......... 0.17 TOP WIDTH (feet) ... 3.00
VELOCITY (fps) ........ 4.53 VEL. HEAD (feet) ... 0.32
AREA (square feet) .... 0.50 P + M (pounds) ..... 22
CRITICAL DEPTH ........ 0.26 CRITICAL SLOPE 0.0048
CRITICAL VELOCITY ..... 2.88 FROUDE NUMBER ...... 1.96
3�
PROJECT: FLOW B.1 - AT DRIVEWAY APRON
DATE: 04 -20 -1999
TRIANGULAR CHANNEL TIME: 10 :39:10
INVERT WIDTH (feet) ... 0.00 MANNINGS n ......... .013
SLOPE (feet /foot) ..... .1000 Q (cfs) ............ 0.24
LEFT SIDE RIGHT SIDE
SLOPE (X to 1) ........ °;100.00 SLOPE (X to 1) ..... 4.00
DEPTH (feet) .......... 0.04 TOP WIDTH (feet) ... 4.37
VELOCITY (fps) ........ 2.62 VEL. HEAD (feet) ... 0.11
AREA (square feet) .... 0.09 P + M (pounds) ..... 1
CRITICAL DEPTH ........ 0.07 CRITICAL SLOPE 0.0075
CRITICAL VELOCITY ..... 1.03 FROUDE NUMBER ...... 3.18
4
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E N G I N E E R S P L A N N E R S S U R V E Y O R S
AMENDMENT # 1 to:
HYDROLOGY /HYDRAULIC STUDY
Ardecky Residence
3461 Calle Margarita, Encinitas, CA
September 20, 1999
SUMMARY! The owner has requested our investigation of the use of PVC curb outlet
as a replacement to the existing design of a D -25 outlet. This amendment report investigates the
use of a manifold drain using 4" PVC lines to penetrate the existing 6 -8" A. C. Curb on Calle
Margarita. Capacity and exit velocity are the chief concerns. Please see original report dated
July 6, 1999, for complete calculations.
FL OWS- 100 - year -flow through this area is determined as 2.24 cfs, by previous report
HYDRATTT.M: ANALYSTS* Flows were analyzed at sections considered critical,
specifically flow A.1+ 2+ 3+ 4+ X.1+ 4 (8" PVC line and multi -4" PVC lines).
Where noted, the manning equation, as follows, was used to determine flow quantities
and sections of flow:
Q - = A * V, where
V = (1.49/n) * r 213 * S 1/2 [ [ M
ENGINr. - " <�� S`' VICES
CI7-' 01= : ,�f- INITaS
Flow Through 8" PVC drain line, A.1+ 2+ 3+ 4+ X.1+ 4:
A computer program utilizing the manning equation was used to determine the flow cross
section at this location. Complete results appear on the attached data sheet.
Q(A.1+ 2+ 3+ 4+ X.1+ 4) = 2.24 cfs, S = 0.05 = match grade to street
For this section, the flow would be at depth of 0.46', with a velocity of 8.65 fps —
OK, pipe adequate.
P. O. Box 791 • Poway, CA 92074 • (619) 748 -8333 • Fax (619) 748 -8412
September 20, 1999
Page 2 of 2
Flow Through 4" manifold drain, A.1 +2 +3 +4 +X.1 +4:
A computer program utilizing the manning equation was used to determine the flow cross
section at this location. Complete results appear on the attached data sheet.
Q(A.1 +2 +3 +4 +X.1 +4) = unknown, S = 0.04
Q� = 0.38 cfs per pipe
2.24/0.38 = 5.89 ... Use a 6 -pipe manifold drain outlet at 4% minimum fall
V = 4.36 fps - adequate for street
This report has been prepared and /or reviewed by the undersigned
- tv,� q� j'4. 1-2
Ernest H. Grabbe, Jr. RCE 0473 Date
Q ROF ESSia
2 No. 0047327 `— :Z
Exp. 12-31-99 ' 'O
Cl VI
�f CALVE
PROJECT: Flow A.1 +2 +3 +4 +X.1 +4 - 8 PVC @ 50
DATE: 09 -20 -1999
PIPE FLOW TIME: 11:24:56
Diameter (inches) ... 8 Mannings n 013
Slope (ft /ft) ....... 0.0500 Q (cfs) ........... 2.24
depth (ft) .......... 0.46 depth /diameter ... 0.69
Velocity (fps) ...... 8.65 Velocity head .... 1.16
Area (Sq. Ft.) ...... 0.26
Critical Depth ...... 0.64 Critical Slope 0.0299
Critical Velocity ... 6.51 Froude Number .... 2.35
PROJECT: Portion of Flow A.1 +2 +3 +4 +X.1 +4 - 4 PVC @ 4%
DATE: 09 -20 -1999
PIPE FLOW TIME: 11:29:31
Diameter (inches) ... 4 Mannings n 013
Slope (ft /ft) ....... 0.0400 Q (cfs) ........... 0.38
depth (ft) .......... 0.33 depth /diameter ... 1.00
Velocity (fps) ...... 4.36 Velocity head .... 0.30
Area (Sq. Ft.) ...... 0.09
Critical Depth ...... 0.32 Critical Slope ... 0.0347
Critical Velocity ... 4.43 Froude Number .... 0.00