2004-1533 CN/G City o -
E .ENGINEERING SE
ncznitas R VICES DEP14RTAIENT
Capital Improvement Projects
District Support Services
Sand Replenishment/Sto Field Operations
nnwater Compliance
Subdivision Engineering
Traffic Engineering
August 17, 2009
Attn: Union Bank Of California
Southern California International Operations Cen
1980 Saturn Street, VO1-519 ter
Monterey Park, California 91755-7417
�: Erich Wilms
1098 Hymettus Avenue
APN 254-262-22
CDP 02-263
Grading permit 1533-G
Final release of security
Permit 1533-GI authorized earthwork, storm drainage
control, all as necessary to build the described
security , site retaining Wall and erosion
y deposited is merited. project. Therefore, a full release of the
Letter of Credit 306S2359599 in te
entirety. The document original isenc lose
d amount Of$1179883.009 is hereby released in its
Should you have an
2779 or in writing, question
g attention s or concerns, please contact Debra Geisha
rt at(760) 633-
Sincerely this Department.,
Q �
Debra Geish
Engineering Technician
Subdivision Engineering Jay Lem bach
Finance Manager
CC: Jay LembAch,Finance Financial Services
Erich Wilms Manager
Debra Geishart
File
ile
TEL 760-633-2600 / FAX 760-633-2627 505 S. Vulcan Avenue, En
cinitas' California 92024-3633 TDD 760-633-2700
s j recyc%d paper
EAST COUNTY SOIL CONSULTATION
AND ENGINEERING, INC.:.-
10925 HARTLEY ROB
SANTEE, CALIFO ', ERYICes DFE'A LENT
(619)258-7 90
Fax 258-7902 I ` (jam
Mr. Erich Wilms
1098 H
Ymettus Avenue � - -
Leucadia, California Cc�o-berA30, 2003
92024 Project No. 03-1147B4
Subject : Limited
Site Investigation
Proposed Single Family
1098 Hymettus Residence
Avenue
City o , APN 254-262-22
f Encinitas, California
Dear Mr. Wilms :
In accordance with
investigation Your request, we
investigation the soil conditions have performed
gation was undertaken at the a limited
criteria for site to subject site. The
gradin Provide the soil
system for the g and recommend engineering
proposed residence, an appropriate
foundation
Our investigation
approximately ound that the
Deposits y 2 feet of colluvium site is underlain
Formation to the and sandstone by
maximum explored de of the Terrace
The construction depth °f 7 feet .
feasible °f the proposed
the design the recommendations herein is
9 and construction, herein geotechnically
are implemented in
Respectfully submitted,
�u (D Mam adou Saliiallo,
RCE 54071 P. E.
MSD/md
WILMS PROJECT NO. 03-1147B4
INTRODUCTION
This is to present
investigation for the findings and
the two-story proposed two- conclusions Of a so.
to be located at 1098 Y over
Of Encinitas Hymettus Avenue basement resident
, California. in the Of
area,
Cit
The objectives of the investigation were to
determine
soils conditions and provide recommendatio
construction. the existin
ns for the propose
In order to accomplish these
trenches were excavated °bjectives, three
and loose tO a maximum de (3) explorator}
bag samples were obtained pth of 7 feet; undisturbec
performed. , and laboratory tests were
SITE DESCRIPTION AND PROPOSED CONSTRUCTION
The subject site
in the is located on the west
Leucadia area, City side of
story residence y °f Encinitas Hnia. s Avenue,
that occupies the California. A single-
slopes moderately to the west , site will be removed.
Avenue to the east Site boundaries The lot
directions . and residential include Hymettus
The proposed construction Properties a the
basement residence, consists of remaining
`� the basement will upper two levels will a two-story over
footings with aill consist of masonry e WO°d-framed and
slab-on- Y walls founded on continuous
grade floor,
FIELD INVESTIGATION
On September 17�
to a 2003, three exploratory
maximum depth of 7. Y trenches were
equipped with a depth
inch bucket . with a John Deere excavated
are shown The approximate 310 SE backhoe
on the attached Plate trench locations
Exploratory Trenches" . No. 1, entitled
` was recorded A continuous "Location of
at the time of excavation°and ist e soils encountered
entitled "Summary Sheet
shown on Plate No. 2
The soils were visuall
filed identification y and texturally classified accordin
No. 3 entitled Procedures set forth g to the
Uniform Soil Classification Charthe attached Plate
2
WILMS PROJECT NO. 03-1147B4
SUBGRADE CONDITIONS
The subgrade soils
investigation were colluvioumntor a during the
soils consisted of tan maximum depth of°2rse of os
low moisture content . Theoocoilu' was undsilt feet. with
sand (SM with
�to dense sandstone of the Terrace Deposits Formation•
y medium dens
EXPANSIVE SOILS
An expansion index test
formational soils to was Performed on
with than determine volumetric a sample Of the
change in moisture content, change characteristics
a ver�low Potential for expansion for the found de on of 3
indicates
GROUNDWATER __._ �� soils. ,
Groundwater was not
investigation, encountered during the
Static groundwater course of our
depths greater than is generally anticipated
affect the 150 feet. We do not expect at
proposed development, P groundwater to
GEOLOGIC HAZARDS
A review of the available
site indicates geological literature pertainIn
the existence of g to the
a1roximatel 2 . 5 Km to the west , the Rose Can on
Zone
or one of the major active faults in then shaking
is the W_. e
from this fault
happening to affect the e most likely
site is comparable to others in With respect to this hazard
general area. � the
The proposed residence
seismic design should be designed in
the g requirements of the 1997 Uniform dance with
Structural Engineers
the SAssociation of California Building Code or
following seismic design criteria: using the
PARAMETER
Seismic Zone Factor, Z VALUE UBC REFERENCE
Seismic Source 0.40 Table 16-I
Soil Profile Ty e B Table 16-U
Near-Source Factor, Na SD Table 16-J
Near-Source Factor, Nv 1'2 Table 16-S
Seismic Coefficient, Ca 1'5 Table 16-T
Seismic Coefficient, Cv 0'53 Table 16-Q
0.96 Table 16-R VVV
3
WILMS PROJECT NO. 03-1147B4
Based on the absence of shallow groundwater and
formational soils, it is
liquefaction is very our opinion that consistency of tt
y low. the potential fc
CONCLUSIONS AND RECOMMMATIONS
The following conclusions and recommendations a
analysis of the data and re based u
investigation, information obtained Pon th
investigation; This includes visual from our soi:
g laboratory testing nspection; fielc
soils native to the site. g and our general knowledge
\ development The site is suitable for g °f the
,during Provided the recommendations set forth aretimpleme°Sec
construction.
nte�
GRADING AND EARTHWORK
Site grading should begin with clearing removal of vegetation and deleterious and grubbing,
the proposed residence materials . g� e. g. the
Terrace Deposits should the colluvium extending In the area of
within 2 be overexcavated g tO the underlying
percent over optimum and the
conditioned
percent relative compaction, compacted to
The overexcavation s minimum of 90
minimum of five (S) feet beyond should extend a
depth and extent of removal Perimeter footings .
the time of should be g The actual
excavation b evaluated in the field at
should be performed in accordan er with the attached this firm. Grading
hed appendix A.
The proposed basement is
the sandstone of the Terrace is anticipated to be entirely founded into
FOUNDATION AND SLAB
a• Continuous and spread footings
two-story residence g are suitable for
extend a minimum of 24nd basement . Continuous the proposed
or the Terrace Deposits Formation. The footings should
properly compacted fill soils
18 inches wide and reinforced with footings should be at least
placed near the to two #S steel bars; one bar
the bottom of the ootingse footings and the other bar
Placed near
b• Concrete slabs
Reinforcement should consist should a minimum
Of 4 inches thick.
center each way. Slab reinforcement bars placed at 16
middle third should be inches on
concrete third of slab by supporting Placed within the
dobies . The slab should be the
by or
Of clean sand over a 10-mil visqueen moisture barrier.
'+ of concrete shrinkage will y 2 inches
�t result ier. The effect
in cracks in virtually all
4
WILMS PROJECT NO. 03-1147B4
concrete slabs . To reduce
should be placed at the extent
a maximum shrinkage,
recommended is aximum of 4-inch slum the concre
intended to prevent shrinka Pe The
minimum
not i ste
c- Where 9 cracks .
moisture sensitive
or carpet, etc. ) are anticipated or coverings (i . e.
moisture barrier should be P over the slab tile, linolet
4 inches underlain b the 10-mil plash
thick, consistin Y a capillary break at
not exceeding 3/4 inch g of coarse sand, leas
the #200 sieve, i11 size with gravel or crushed roc
no more than 5 percent passin
d• An allowable
soil bearing value of
may be used for the 2. 500 pounds
founded a minimum design of continuous per square foot
or the of 24 inches into and spread footin
�. Terrace De compacted g-
1, 250 _, posits Formation. Y compacted fill soils
PPSf and _730 psf for This value -..��_o
respective) each additional foot may be increased`by
- y to a maximum value of 4 - - Of depth and width,
e. Lateral _ --
. 500 lb7ft _ ..._.v_.. v_.-- d- w -.t
the resistance to horizontal
soil passive movement
soil . An allowable pass - and the friction may be provided by
per foot of Passive pressure between concrete
depth may of 250 Pounds and
friction °f 0. 4 Y be used. An allowable per square foot
.,- _ is reco coefficient
as the bearin �-- �.-__°'-�--mmended. The soils
loading, g value ma passive ° ° --°f
Y be increased b Pressure as well
Y 1/3 for seism
wind and
RETAINING WALLS
Cantilevered retaining walls with
to resist an active a level backfill may
cubic __foot , equivalent fluid Y be designed
free This Pressure is pressure °f 35
draining and based on the backfill mounds der
approved b non-expansive. Backfill soils being
y the soils engineer prior to materials
use, must be
Restrained walls
rotate should be ' such as basement walls,
designed to resist that are not free to
pressure of 55 pounds per cubic an ,Nat-rest"
foot. -------_ e qu i va l e
_ fluid
TE14PORARY SLOPES AND TRENCH BACKFIL Y'M =•a_,.
L
Excavations for
made vertically on-site utility trenches
sloped at for shallow depths and temporary cuts may be
1H: 1V for depths P and must be either shored
should be observed greater than 4 feet; or
and backfilled during construction. OSHA guidelines
depth with clean Utilities should be
P of at least sand or approved bedded
uniform) one foot over the granular soil
Y watered and Pipe. This backfill to a
compacted to a firm should be
condition for pipe
5
WILMS PROJECT NO. 03-1147B4
support. The remainder
soils or non Of of the backfill should
thin lifts the
soils be select on-si
moisture-conditioned which should be placed
relative compaction. and compacted to
at least g(
DRAINAGE
Adequate measures should
the site after the structures undertaken to
such and other improvements properly finish grad
that the drainage water the site are
properties is directed away ithin the in Place
slabs and Y from the foundations to and adjacen7
the tops of slopes via surface footings, floor
drains towards the swales and
and subsurface drainage will drainage for this area . subsurface
an water required to proper surface
seeking the level of minimize the
foundations, footin s the bearing
otential
in undermining g and floor slabs g soils under the
g and differential ' which may otherwise result
other improvements . settlement of the structures and
LIMITS OF INVESTIGATION
The recommendations
site investigated and provided in this report
conditions do not deviate from upon h set the only to the
assumption that the soil
any variations or undesirable disclosed in the trenches . If
construction, or if conditions are encountered
differ from that the proposed construction will significantly
Consultation Planned at the present Y
and Engineerin time, East Count
supplemental recommendations can be should be notified Y Soil
provided. so that
Plates No. 1 through
and A 3, Pages L-1, Shear Test Results
Ppendix A are parts of this report .
References
Respectfully submitted,
�RMESS/pN
P�pU S. -lF2
w No.C054071 <� m
rt Exp.re-V-3 .a
CI ll P��P
L .
Mamadou Saliou Diallo, p. E.
RCE 54071
MSD/md
6
N-
71-
o�
h
EAST COUNTY SOIL CONSULTATION
& ENGINEERING, INC.
10925 HARTLEY RD..SUITE 1,SANTEE CA 92071
(619)258-7901 Fax(619)258-7902
-3 �ZoG
WILMS PROJECT NO. 03-1147B4
PLATE NO. 2
SUMMARY SHEET NO, 1
TRENCH N0. 1
DEPTH SOIL DESCRIPTION
Surface COLLUVIUM Y
(Qal)
tan, damp, loose
fine r
silty sand (SM) with g aired
2. 0' TERRACE DEPOSITS palm tree roots
(Qtz)
tan, moist, medium dense
2 5 fine-grained silty sand to dense,
(SM)
5. 0'
7. 0' 113. 6 6. 6
trench backfilled 9f trench, no caving, no groundwater
105. 9 8.2
-------------------/17/03----------------
TRENCH NO. 2
DEPTH SOIL DESCRIPTION
Surface COLLUVIUM Y M
(Qal)
tan, damp, loose
silt , fine grained
2. 0, y sand (SM)
TERRACE DEPOSITS (Qt2)
tan, moist, medium dense
6. 0 fine-grained silty sand to dense,
bottom of trench (SM)
trench backfilled g
no caving, no groundwater
/17/03
-----------------------------------------------
TRENCH N0. 3
DEPTH SOIL DESCRIPTION
Surface COLLUVIUM Y M
(Qal)
tan, damp, loose,, fine grained
2. 0' y sand (SM)
TERRACE DEPOSITS (Qtz)
fine-grained silty
tan, moist, medium dense dense,
o
3. 0' bottom of sand (tto
trench
trench backfilled 9 no caving, no groundwater
------------------ /17/03-----------------------
7
MAJOR DIVISIC -S SYMBOL
Gam, DF`".'RIPTION
WELL GRADED GRAVELS OR GRAVEL.SAND
GRAVELS GP MIXTURES.LITTLE OR NO FINES
(MORE THAN%, POORLY GRADED GRAVELS OR GRAVEL-SAND
OF COARSE MIXTURES.LITTLE OR NO FINES
FRACTION GM
>NO.4 SIEVE SILTY GRAVELS,GRAVEL-SAND-SILT MIXTURES
COARSE SIZE)
GRAINED SOILS GC
CLAYEY GRAVELS,GRAVEL-SAND CLAY MIXTURES
(MORE THAN%:OF SOIL>
NO.200 SIEVE SIZE) Sw
WELL GRADED SANDS OR GRAVELLY SANDS,
SANDS SP LITTLE OR NO FINES
(MORE THAN%, POORLY GRADED
OF COARSE SANDS OR GRAVELLY SANDS,
FRACTION SM LCt'tLE OR NO FINES
<NO.4 SIEVE
SIZE) ND SILTY SAS,SILT-SAND MIXTURES
SC
CLAYEY SANDS,SAND-CLAY MIXTURES
ML INORGANIC SILTS AND VERY FINE SANDS,ROCK
SILTS & FLOUR,SILTY OR CLAYEY FINE SANDS OR CLAYEY
CLAYS SILTS WITH SLIGHT PLASTICITY
LIQUID LIMIT CL INORGANIC CLAYS OF LOW TO MEDIUM
PLASTICITY,GRAVELLY CLAYS,SANDY CLAYS,
FINE GRAINED <�0 SILTY CLAYS,LEAN CLAYS
SOILS OL
(MORE THAN%,OF SOIL< ORGANIC SILTS AND ORGANIC SILTY CLAYS OF
NO.200 SIEVE SIZE) MH LOW PLASTICITY
SILTS & INORGANIC SILTS,MICACEOUS OR DIATOMACEOUS
CLAYS CH FINE SANDY OR SILTY So SILTS
LIQUID LIMIT INORGANIC CLAYS OF HIGH PLASTICITY FAT
>50
OH CLAYS
ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY,
HIGHLY ORGANIC SOILS Pt ORGANIC SILTY CLAYS,ORGANIC SILTS
PEAT AND OTHER HIGHLY ORGANIC SOILS
CLASSIFICATION CHART(UNIFIED SOIL CLASSIFICATION SYSTEM)
CLASSIFICATION RANGE OF GRAIN 70
SIZES
U.S.STANDARD GRAIN SIZE IN eo I I I f
BOULDERS SIEVE SIZE NIILLIIVIETERS
COBBLES Above 12 Inches Above 305 30
12 Inches To 3 Inches
RAVEL 305 To 76.2
3 I I I I
G Inches to No.4
Coarse 3 Inches to'/.Inch 76.2 to 4.76
76.2 to 19.I I I I I
Fine '/.Inc 1 to 4 76
h to No.4 3o
19 = I
SAND No.4 to No.200 r,
Coarse No.4 to No. 10 4.76 to 0.074 .o I
Medium 4.76 to 2.00
No. 10 to No.40 io I yMYCN
Fine No.40 to No.200 2.00 to 0.420
uic`_JL
SILT AND CLAY 0.420 to 0.074 S ; i
Below No.200 Below 0.074 0 o Zo io
GRAIN SIZE CHART 30 so a0
°
uowo um.r ! '10 �° 00
PLASTICITY CHART
EAST COUNTY SOIL CONSULTATION
AND ENGINEERING, INC.
10925 HARTLEY ROAD,SUITE "I" tt!f SANTEE, CALIFORNIA 92071 U.S.C.S. SOIL CLASSIFICATION
WILMS PROJECT NO. 03-1147B4
PAGE L-1
LABORATORY TEST RESULTS
RESULTS OF EXPANSION INDEX TEST
An expansion test in conformance with AST
e c
epresentative
on-site soils to determine volumetric change characteristics
M D4829 was performed on a r
recorded expansion of the sample is presented as follows: with change in sampl
moisture content. Th
INITIAL SATURATED
MOISTURE MOISTURE INITIAL DRY
CONTENT% CONTENT/o DENSITY EXPANSION
o LB_16U. FT.
8.5 INDEX LOCATION
15.3 115.1
3
T-1 @ 2.5'
RESULTS OF PARTICLE SIZE ANALYSIS
U.
S: Standard
Sieve Size Percent
��ASTM D-422
fi�13@2
1"
1/2" _
3/8" _
#4 _
#8
#16 100
#30 99
#60 91
#100 36
#200 23
19
INC
SM
8
DIRECT SHEAR SUMMARY
5000
4500
4000 i
3500 —
a. 3000 f - - --- - - ---
LU
2500 ; ------ --_ — _
y r
I2 2000 --__-
k - ---
j 1500
1000 r - - ---------
500 I
o
i
C 500 1000 1500
2000 2500 3000 3500 4000 4500 5000
I
NORMAL STRESS [PSF] (2 3/8" SAMPLE)
I
I
I
ANGLE OF COHESION
SAMPLE DESCRIPTION INTERNAL
FRICTION (0) INTERCEPT
Hymettus (PSF)
Undisturbed
TERRACE 35 °
100
DEPOSITS
WILMS PROJECT
S C. SOUTHERN CALIFORNIA
S-T; SOIL & TESTING INC. ECTL - HYMETTUS _
...- � BY: DBA/SD
JOB NUMBER: 03-1147B4 DATE: 9/26/2003
PLATE NO.:
WILMS PROJECT NO. 03-1147B4
REFERENCES
1 • "1997 Edition, Uniform Buildin
Engineering and Design Provisions". g Code, Volume 2
Structura,
Adjacent Po tions Active Fault Near-Source Zones in C
Edition of the Uniform Nevada-, Page 0-37 alifo anc
9 , used with the he 1991
Conference of Building Official Code, Published b
y International
3 . "Geologic Maps of the Northwestern Part
California. Plate No. 2, Geologic Maps Of San Diego
g p of the Encinitas and County,
Santa Fe 7 . 5' Quadrangles", by Siang S. Tan and
Michael p,
Kennedy, 1996.
9
EAST COUNTY SOIL CONSULTATION
AND ENGINEERING, INC.
10925 HARTLEY ROAD, SUITE I
SANTEE, CALIFORNIA 92071
(619) 258-7901
APPENDIX A
RECOMMENDED EARTHWORK SPECIFICATIONS
1. General Description
The intent of these specifications is to obtain uniformity
that the proposed structures may be safely supported- and adequate strength in filled ground so
preparation of the land to be filled, processing the fill soils, the Preadin include the clearing and
filled areas to conform with the lines and grades as shown on the approved g, and compaction of the
PP d plans.
The owner shall retain a Civil Engineer qualified in soil mechanics here'
to inspect and test earthwork in accordance with these specifications. The
owner and grading contractor immediately if ( in referred to as engineer)
and shall have the authority to reject the compacted fi engineer shall advise the
any unsatisfactory conditions are observed to exist
measures are taken, necessary to comply with the specifications.ground hall becthe s
of the grading contractor to achieve the specified degree of c tiiTie that corrective
'�' compaction:
sole responsibility
2. Preparing Areas to be Filled
disposed of so amts leave vegetation t areas any biodegradable refuse shall be rem
filled ground or loose compressible n natural grlound shall be and debris.removed or otherwise
otherwise. An moved unless the report recommends
Any buried tanks or other structures shall be removed and the depression ba ckflled to
the satisfaction of the engineer.
(b) The natural ground which is determined to be satisfactory for the s upport of the filled
around shall then be plowed or scarified to a depth of at least 12 inches (12").
(c) After the natural ground has been prepared, it shall then be brought
moisture content and compacted to not less than 90 percent of maximum dry
with ASTM D1557-91. ,ht to the proper
, density in accordance
(d) where fills are made on slopes greater than 20 percent, horizontal be
into the firm natural ground. The initial bench at the toe of the fill shall be a least
on firm undisturbed natural ground. The width of all succeeding shall be cut in width
ins o benches shall l be at feet least 6 feet.
APPENDIX A
3. Fill Materials
All material shall be approved b
matter, and other lumps Y the engineer and shall consist of materials free from v
found w P greater than 6 inches in diameter. If, during which were not encountered egetaE
shall be performed to determine theiand tested in the prelimin g grading operations, soils a
in the Preliminary Physical characteristics. pry Investigation, tests ec these d
pry or subsequent soils reports not covered herein shall pbeattnent recommends
these specifications.
become an addendum t
4. Placing and Compacting Fill Materials
added until the moisture content of the fill material i
moisture content is is below that specified, water shall be
compaction. near optimum to assure uniform
mixing and effective
shall be(aerated eb the moisture content of
near optimum as pecified the fill materials is above
o and scarifying or other satisfactory that specified, the fll material
• ry methods until the moisture content is
(c) After processing, the suitable fill materials s
compacted, shall not exceed six inches
thoroughly hall be placed d layers which, when
�hly mixed during the spreadinv ' �6�)' Each layer shall be spread event
Insure uniformity of materials and y and shall be
(d) After each layer has been moisture in each layer.
compacted A not less than the density mixed
accomplished with a and spread evenly, it shall be
approval ty set forth in paragraph 2 (c) above. thorough)
the fill material is at types of compaction equipment. Rolling Compaction shall be
accordance with ASTM D1 specified moisture content. D shall be accomplished while
place density tests shall be performed in
(e) The surfaces of the fill slopes shall be compacted
suitable equipment. Compacting pacted b
there is no appreciable operations shall be continued until the slopes sarre stable d other
ppreciable amont of loose soil on the slopes.
5• Inspection ble and until
Sufficient inspection b
S maintained durin y our firm or the Soil's Eno
g the filling and com `ineer of record and/or his/her representative shall
was constructed in accordance with the accepted s operations perations so that he/she can verify that the fill
P specifications.
6. Seasonal Limits
No fiIl material shall be
content above Placed, spread, or rolled if weather conditions increase Permissible limits. When the work is interru interrupted b
resumed until the moisture content and density of fill are as ass the
P y rain, fill operations shall not be
All recommendations presented in the attached Previously specified.
report are a part of these specifications.
HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
1098 Hymettus Ave, Leucadia, CA 92024
APN 254-262-22
Project No: 031014
W.O. # XXXX
Grading Permit # XXXX
QROFESS/pN
AS
No 702 z
' m
Ex 12/31/05
C/vl\- �P
qTf CA��F
Prepared By:
ENGINES
RING
ca.NSUI.�NG
GROUP
PH:(858)259-4711 FX:(858)259-5732
Original: February 1, 2004
Revised: February 12, 2004
HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
TABLE OF CONTENTS
1 INTRODUCTION
1.1 Project Site Descrriptiipti.......................................................................................
on
1.2
Topographic Source ..............
1.3 Proposed Project
2 RUNOFF CALCULATION
2.1 Design Methodology
hodology.,,,,,,,•••••
2.2 Pre Construction Design Runoff
noff......................................................................
2.2.1 On-Site Runoff.............
2.2.2 Off Site
Runoff............ ............................. ,
2.3 Post Construction De 11
2.3.1
Design Runoff................................................................... 1;
On-Site Runoff.......................
2.3.2 Off— Site Run 1�
Runoff.............
2.3.3 Total Post Construction Runoff............................................................... 1
SUMMARY AND
3.1 Drive CONCLUSIONS........................................................................ 16
Driveway Drainage................
3.2 Driveway .... 16
y drain inlet """'�••••••••••
3.3 Drainage Piping and piping...................................................................... 17
3.4 p g Adjacent to ALU ............
Surface Drainage at South ................................................... 17
4 Side of SFR.................................
REFERENCES AND ABBREVIATIONS ..................••••• 19
4.1 References ........................................20
. . .............................................
4.2 Abbreviations........ ....................................
DECLARATIO N OF RESPONS "'
..... . ..................20 IBLE CHARGE.........
Figure 1 Vicinity Ma LIST OF FIGURES
Figure 2 Overlay of the Soil Runoff Potential Map on the Project Site....
Figure 3 Runoff Coefficients as a function of Land use and Soil Group
Figure 4 Six Hour Precipitation for 100 Year Storm Frequency Figure 5 Twenty ........................6
my Four Hour Precipitation for 1 q Y 7
Figure 6 Pre Construction 0 Year Storm Fre
ction Site
Frequency 8
......................
Figure 7 Off Site Hydrologic Sub areas
Figure 8 Post Construction On-Site Sub ""' 11
Figure 9 Open Channel C areas............................................................ 14
Calculations for Driveway
Figure 10 Driveway Drain Inlet """ 17
Figure 11 Dr and Piping Calculation
Drain Line Calculations s """"""••••••••••••••••••••••............ 17
Figure 12 Drain - South of ALU
Line Calculations - ALU North. •..'•'•.".""" • 18
..........................
Figure 13 Vegetated Swale Calcul
ations - SFR South................................................. 19
N:\Prof ects\ADA_031014\Docs\Hydrology.doc
Revised: 2/12/2004 Page i
HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
1 INTRODUCTION
This hydrology study is prepared to determine the pre construction and post
construction influence of precipitation on the proposed project development.
1.1 Project Site Description
The 0.46 AC project site is located on the west of Interstate Highway 5 in the Cit of
Encinitas (See Figure 1 — Vicinity Map). The project is approximately y
of the intersection of Leucadia Blvd and Hymettus Ave and 1260 feet west of feet no h
Inte stat rt
5. The project site is legally described as;
THE NORTHERLY 100.00 FEET OF LOT 13 IN BLOCK 8 IN SOUTH COAS'
PARK, IN THE COUNTY OF SAN DIEGO, STATE OF CALIFORNLA
ACCORDING TO MAP THEREOF NO. 1776, FILED IN THE OFFICE OF THI
COUNTY RECORDER OF SAN DIEGO COUNTY, JAN. 11, 1924. EXCEPTINC
THEREFROM, THE WESTERLY 100.00 FEET.
The project area is characterized as a gently sloping knoll with an average slope of
12%. The existing on site elevations range from 141.7 Mean Sea Level (MSL) at the
northwesterly corner of the site to 157.8 MSL at the southeasterly corner of a existing
on-site single family residence. g
1.2 Topographic Source
The topography used for this study is derived from two sources. On-site topography
was derived from the project survey as described on the project plans. Off site
topography was derived from the County of San Diego Topographic Survey, Panel
326-1677 and 330-1677, dated 4-5-1973. Y
1.3 Proposed Project
The project site and surrounding area is designated residential R-3, and is current ly
utilized by a single family residence. The proposed project will demolish the existi ng
single family residential structure and construct a new four bedroom residential
structure and an attached accessory living unit with one bedroom and a kitchen.
N AProj ects\ADA_031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
wirwrr eew•���w�ww���w°�,
-0 GOS'C P
n LP
0 ANDREW Av OFT R
0
rn
Z =
z n m �O`GN O C
Z °p c v
SANFO o
G <
Z $ >
YL L <
� m
r y fi N
O N Z
�L fi G
� 2
N m
y G
L N
D
PROJECT
yL L A
SITE B
G)
v m
L P ES A
y G N
� 2
2 UNION S
i
Z-
0 G ° ° 15
2 m
L
(Zt1 L N m
Z yL Source:SANDAG GIS data, PLSS GIS
data,Record Information,San Diego
County Cartography Department
ENGINEERING Wilms Residence
CONSULTING Vicinit Ma SHW
GROUP y 1098 Hy GM$ Ave
Leucadia, CA 92024
Figure 1 Vicinity Map
N:\Projects\ADA-031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
2 RUNOFF CALCULATIONS
2.1 Design Methodology
The watershed is less than 0.5 square miles; therefore the Rational Formula has bees
selected to calculate runoff.
Q = CIA
Where,
Q = Peak Rate of Flow (cfs)
C = Runoff Coefficient
I = Average rainfall intensity (in/hr)
A = Drainage Area (acres)
2.2 Pre Construction Design Runoff
2.2.1 On-Site Runoff
The drainage area for on site runoff totals 0.46 acres.
The soil runoff potential for this site is determined by overlaying the site on the Soil
Runoff Potential Map Panel 33 Encinitas
published by the C DPLU. The Soil Runoff Potential Overlay sshownin Figure.2 my of San Diego,
The soil runoff potential for this site is soil group A. The runoff coefficient for this site
can be determined by cross referencing the soil group with the land use and using the
table shown in Figure 3. The runoff coefficient C for this site is calculated as follows
persuant to section 3.1.2 of the COUNTY Hydrology
Land Use Character►stc Manual
Permeable 'Coe �ploo sf *
;ground surface
Imperv�ocs surf
e
O
�St,btotal-
W d""
Averag"eC , . 3� t�03 � � 604
t: . 0 59
�g
The storm frequency for this study has a 100 year recurrence interval.
The six hour anticipated precipitation for the project site subject to the design storm
frequency; P6 is shown in Figure 4. The twenty four hour anticipated precipitation for
the project site subjected to the design storm frequency; P24 is shown in Figure 5.
P6 = 2.4 inches
P24 = 4.1 inches
The time of concentration across the project site Tc is determined from the followin
formula (San Diego County Hydrology Manual, dated June 2003). g
Tc = ((11.9L3)/H)0.385
N:\Projects\ADA_031014\Does\Hydrology.doe
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HYDROLOGY AND HYDRAULIC STUDY
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Where,
Tc = Time of Concentration in hours (Tc > 5 mins)
L = Length of Watershed (miles)
H = Difference in elevation along effective slope line (ft)
The preconstruction on-site topography is shown in Figure 6.
Area
L = 200/5280 = 0.04 miles
H = 157.8 — 141.7 = 16.1 feet
Tc = 1.3 mins => Tc = 5 mins
The average rainfall intensity can now be calculated from the following equation San
Diego County Hydrology Manual, June 2003).
1 = 7.44*P6*D-0.645
Where,
I = Rainfall Intensity (in/hr)
P6 = Six hour precipitation (inches)
D = Duration (min.)
Therefore,
I = 6.32 in/hr
The site area in acres, A = 0.46
The pre construction site runoff, Q is calculated as follows;
QPRE = CIA = 0.59*6.32*0.46
QPRE = 1.72 cfs
N:\Projects\ADA_031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
...w�wrw�.•°wu.°r
LeD2
1pIC ,fie
sB 6oF Ao Qry
Cr
Q s
u�t
Cs d0ooy O s�
tip
0�
6 Cs0
c ca Cd31r reF Q
TeF
T MI �Jq
MIC CfD2
s
N 41
5
0
sc
AtF
LEUC
MIC fD2 CfCo
AJ
k fe
_ PROJECT c q
y SITE
a fUt A
r Cf
z MtC Cf
MIE M�
• CfC
9
02
MI;, bD
C MR
a
c� y C
ME s
! A
7Z z x 16 MIE
a MIC US
MIC
Source:SANDAG GIS data,Record
Information,Soil Runoff Potential Map
Panel 33.Encinitas by DPLU
9 ENGINEERING Wllms Residence
CONSULTING Soil Runoff Potential Overlay 3HW
1098 Hymettus Ave,
s ■>> °' Leucadia, CA 92024
« �
MM
Figure 2 Overlay of the Soil Runoff Potential Map on the Project Site
N:\Projects\ADA_031014\Dots\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
Runoff Coeff►cren#s for; a re s
1riRd USe (J Il §.nr
y � Runoff Coefficient
s4
( RG Elernen#s Soil Type
County Elements
Undisturbed[Natural Te#rafi% permanent Cpen spacef?e Q A ° C
Low'Density Re�rdential LDf � k� 0.20 14� 0.3(
} ; Residential, 10 DU/A or less 0 27 "
Lowj4ensrty Resfden#►al LOR =: 3� 0.3E
Residential,2.0 DU/A or less
Low'DensityEResidefttial LDR � 0.34 0.42
e Residential, 2.9 DU/A or less2
Medrum 1?ensrtyR�esrdentialgMOR Residential,4.3 DU/A or less 0.38 �4 . 0.46
� � 0.41' # 4 0.48
lUledf>tm Dene1#yROsrdentral MDR Residential 7.3 DU/Aor less °
Med►um Denstt�rR sf0,1004 MD1i Residential, ' 0.48 0.54
� ,. 10.9 DU/A or less �;' 0.52
Mediumt?es� Rstr ientlal MCI Residential, 0.57
<( 14.5 DU/A or.less
Htgh Density Res►denfiat HDR 0 55 5 0.60
Residential, 24.0 DU/A or less
RrgEt>Oensit Residential HDR 0 0.66f}fi -� 0.69
Residential, 43.0 DU/A or less �
Commerclaf/tndustrraf N Com ztr 0.76 ( 0.78
Neighborhood Commercial
ComrnerQrel/fncfusiciaC G`CQrn8tk 0.76 0.78
General Commercial
Cornr>7ereia(/IridUSfrral (p P Comb , Office Professional/Commercial 0.80 ;$3 0.81
Commercrafffndustr al(L,irr fted i)' � � 90 0.83;10 8g� 0.84
Limited Industrial(General I General Industrial 0.83 - t 8 0.84
}y{
0.97 121 0 87
9 CQUn l't drQtO m � � �
Saurce Table 31 San Die`o tY
Y g °Manual, tiane�2003 ��z
Figure 3 Runoff Coefficients as a function of Land use and Soil Group
N:\Projects\ADA_031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
0
b'
3,5 X36 yp
9�y 4.5 S
v s `•'
.p o
ryy 3V w
'sJ �
P
4.0 2.5
35 ) 2S
w
o w
PROJECT
SITE a 3o
b
5J >
U o
U
2.5 qp
0
w
•o
3�
3.5\ 4.5
�p 35 •o
3"
ti5 �5
9p
Z.o
Source:SANDAG GIS data, PLSS GIS
data,Record Information,San Diego
County Hydrology Manual,June 2003
ENGINEERING Wlims Residence
CONSULTING 6 Hour Preci itation - 100 r Storm
GROUP '� u 1098 Hymettua Ave.
Leucadia, CA 92024
« f sKCrs
Figure 4 Six Hour Precipitation for 100 Year Storm Frequency
N:\Projects\ADA-031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
w w.w.wr wwtw�_r�ws�w��wwaw.waw
w.w.rw.ww_�wwa�w�
try.
e0
6.0 50 .
50 G 6'0 50 S O
5.0 0 O°° 0,0'0 9s °
by \
° 8.0
1.0 50
60 80 10.0 a �° 45
40 4.0—
10
3.5
PROJECT
SITE u v0
D'o o S.S
to m 6.0 m 60
p m 8.0
9JJJ 8.0�
h N^ \ 5.0
U 13.0 0 0 4.5
9�S O 65 4.0
L6.0
b•
5.5 2.0
4.5 .0 /$O 100
4.0 8.5 / / a
`J o
5.57 ^4 1 y0 SO
4 0 V roo,
Source:SANDAG GIS data, PLSS GIS
data,Record Information,San Diego
County Hydrology Manual,June 2003
ENGINEERING Wilms Residence
CONSULTING 24 Hour Preci nation - 100 vr
GROUP ,.� 1098 Hymettus Ave.
e ,„ Leucadta, CA 92024
Figure 5 Twenty Four Hour Precipitation for 100 Year Storm Frequency
N:\Proj ects\ADA_031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
w riw•:rr:
r°'.�
w sl°1w•rr w.wwww.r�rlrwr41w'..Ilw�
er.wrw..l�.wrw,r
..rr.n� 1AT ._war•
u �
°II
NI Ml
{ . tr to
l �p ul
ZOO
X to
MI
y LE I If
a t
t I�
t e � I1 A
� 1 i
0
p
g r
MI
.1
1
Source:Project Survey
HYmettus � .,..,,... +�Aver�u�
ENGINEERING Wilms Residence
CONSULTING Pre Construction $Ite TO O ra h
9
GROUP ,
1088 Hymettua Ave.
Leucadia, CA 82024
Figure 6 Pre Construction Site Topography
N:\Proj ects\ADA_031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
2.2.2 Off Site Runoff
The project site is located at the top of a knoll. All surrounding property is draining
away from the project site. Zero off site runoff enters the site as shown in figure 7 an
attached exhibit H-1.
N:\Projects\ADA-031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
r..ww�rw
wwrewc� wwrw.w eto
w.waw.wwww��+w ww�"iwwa�ww ww
�"r�r��rsawr
` '. k"
Vtk
VT
�axr s z
wrw•5
n r. `
0
Z
-7 : , Source:Project Survey
ENGINEERING "-
Wilms Resid ence
CONSULTING PreConstruction Site To o ra h SHEET
GROUP Iw aye "" mss 1098 Hymettue Ave. i
es Leucadia, CA 92024 1
Figure 7 Off Site Hydrologic Sub areas
N:\Projects\ADA-031014\DOcsHYdrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
2.3 Post Construction Design Runoff
2.3.1 On-Site Runoff
The post construction drainage patterns are as shown in Figure 8.
The runoff coefficient C for this site is calculated as follows pursuant to section 3.1.2
the COUNTY Hydrology Manual:
Land Use Character•rst�c ' a Coeffrcreir�t�� ��A,.A�re�}sf ,�,,,;� �r� � ,.;�
Permeabletgrdund sur#ace �� Q 9
81'VIC� ` ` �
Imp uS�surfac���� ��E ` �-��� ��, ,��� � .���� �� ���9�4t1�45� s..
Subtotals g � � �� 8
Weig(iteci !4 06 ;
The time of concentration across the project site Tc is determined from the foll
formula (San Diego County Hydrology Manual, dated June 2003). owing
Tc = ((11.9L3)/H)0.385
Where,
Tc = Time of Concentration (hours) (Tc > 5mins)
L = Length of Watershed (miles)
H = Difference in elevation along effective slope line (ft)
Area 1
L = 128/5280 = 0.024 miles
H = 153.5 — 148.5 = 5 feet
Tc = 1.14 mins => Tc = 5 mins
The average rainfall intensity can now be calculated from the following equation
(Design and Procedure Manual, App XI-A).
= 7.44*Ps*D-1.145
Where,
I = Rainfall Intensity (in/hr)
P6 = Six hour precipitation (inches)
D = Duration (min.)
Therefore, I = 6.32 in/hr
The site area in acres, A = 0.46
Using the revised runoff coefficient the post construction site runoff, Q is calculated as
follows;
QPOST = CIA = 0.66*6.32*0.46
N:\Projects\ADA-031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
QPOST = 1.92 cfs
N:\Projects\ADA_031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
wMeewM_'e�iri% w��wri.w�
M�r_w.>.wrww.�ra.rw�rw���
w�rwe���aw�r
I S
I � µ
I I I I vm�
I
1/ AREA=14 $F Vim a
x
I � I
I / I
I I 1 I
AREA=3738 SF I
m
I I'
I I
AR ° I
I EA 932 SF I
I� 0 I
tl AREA=25 �SF
ro
IL I
4 A A=183SF I
O 6 AREA=370SF I
AREA=785 SF I
Source:Project Plans
ENGINEERING Wilms Residence
CONSULTING Post Construction On-Site H drolo *
GROUP 1098 Hymettus Ave.
ea.n Leuasdie, CA 92024
Figure 8 Post Construction On-Site Sub areas
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
2.3.2 Off— Site Runoff
The post construction off site runoff will not change.
QPOST = 0 CfS
2.3.3 Total Post Construction Runoff
The combined total runoff from both on-site and off-site drainage sub-areas affecting
the project site is 54.9 g
QPOST = (QONSITE+ QOFFSITE)
()POST = 1.92 + 0
QPOST = 1.92 cfs
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
3 SUMMARY AND CONCLUSIONS
The proposed improvements to the grading will affect the quantity of storm water run
from the project site.
Kl-
MR
4
P
n
.difference _
On site discharge due to storm water run off will increase a o
(0.20cfs) to 1.92cfs. This is due to a increase of 13% in the amount of on site
impervious area and a corresponding increase in the runoff coefficient for the site.
This on site discharge will be routed off site via surface drainage and local storm
drains.
3.1 Driveway Drainage
The driveway is designed to catch runoff from half of subarea 1, and all of subareas 3
4 and 6.
A = 4998SF = 0.115AC
()DESIGN = 0.66*6.32*0.115 = 0.48 cfs
S = 0.054
Side Slopes, H: V = 50:1
Channel Calculator
Given Input Data:
Shape
Solve for Advanced
Flowrate Depth of Flow
Slope 0.4800 cfs
Manning's n 0. 0540 ft/ft
Height 0.0130
Bottom Width 12 .0000 in
Left Radius 0. 0000 in
Right Radius 0. 0000 in
Left Slope 0.0000 in
0.0200 ft/ft
Right Slope (V/H)
0. 0200 ft/ft
Depth Computed Results: (V/H)
Velocity 0.7307 in
Full Flowrate 2.5895 fps
Area 836.5613 cfs
Perimeter 50.0000 ft2
Flow Area 1200.2400 in
Flow Perimeter 0.1854 ft2
Hydraulic Radius 73 .0797 in
Top Width 0.3653 in
Percent 73 .0651 in
Critical Information: 6. 0888 %
Critical De th
1.0735 in
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HYDROLOGY AND HYDRAULIC STUDY
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Critical slope
Critical velocity 0. 0069 ft/ft
Critical area 1.1996 fps
Critical perimeter 0.4001 ft2
Critical hydraulic radius 107.3697 in
Critical top width 0.5366 in
Specific energy 107.3482 in
Minimum energy 0.1651 ft
Froude number 0.1342 ft
Flow Condition 2 .6164
Su ercritical
Figure 9 Open Channel Calculations for Driveway
3.2 Driveway drain inlet and piping
Q = 0.48Cfs
L = 88LF
FDiameter pe Calculator
Circular
Depth of Flow
t Data:
4.0000 in
0.4800 cfs
Manning's n 0.0568 ft/ft
Computed Results: 0.0090
Depth
Area 2 .5432 in
Wetted Area 0.0873 ft2
Wetted Perimeter 0. 0585 ft2
Perimeter 7.3833 in
Velocity 12.5664 in
Hydrualic Radius 8.2005 fps
Full flow flowrate 1.1416 in
Full flow velocity 0.6552 cfs
7.5075 fps
Figure 10 Driveway Drain Inlet and Piping Calculations
3.3 Drainage Piping Adjacent to ALU
Two drain lines pass to the north and to the south of the accessory living unit (ALU).
The line to the north collects nuisance drainage from the driveway wall and half the
runoff from sub-area 7 covering the ALU. The line to the south collects runoff from the
driveway drain inlet and half the runoff from sub area 7.
Q = 0.55Cfs
L = 44ft
S = 0.009
Manning Pipe Calculator
Shape
Solve for Circular
De th of Flow
N:\Projects\ADA-031014\Docs\Hydrology.doc
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
FInput Data:
ter
ate 6. 0000 in
0.5500 cfs
Manning's n 0. 0090 ft/ft
Computed Results: 0.0090
Depth
Area 3 .7531 in
Wetted Area 0.1963 ft2
Wetted Perimeter 0.1292 ft2
Perimeter 10.9472 in
Velocity 18.8496 in
Hydrualic Radius 4.2563 fps
Full flow flowrate 1. 6998 in
Full flow velocity 0. 7689 cfs
3.9160 fps
Critical Information:
Critical Depth
Critical slope 4.6643 in
Critical velocity 0.0046 ft/ft
Critical area 3 .2832 fps
Critical perimeter 0.1675 ft2
Critical hydraulic radius 12 .7533 in
Critical top width 1.8915 in
Specific energy 6. 0000 in
Minimum energy 0.5941 ft
Froude number 0.5830 ft
Flow Condition 1.4794
Su ercritical
Figure 11 Drain Line Calculations-South of ALU
Q = 0.10cfs
L = 107
S = 0.053
Manning Pipe Calculator
Shape
Solve for Circular
Depth of Flow
Given Input Data:
Diameter
Flowrate 4.0000 in
Slope 0.1000 cfs
Manning's n 0.0530 ft/ft
Computed Results: 0.0090
Depth
Area 1. 0750 in
Wetted Area 0.0873 ft2
Wetted Perimeter 0.0189 ft2
Perimeter 4.3600 in
Velocity 12.5664 in
Hydrualic Radius 5.2945 fps
Full flow flowrate 0. 6238 in
Full flow velocity 0 . 6329 cfs
7.2520 fps
Critical Information:
Critical Depth
Critical slope 2.1200 in
Critical velocity 0. 0044 ft/ft
2.1292 f1ps
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HYDROLOGY AND HYDRAULIC STUDY
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Critical area
Critical perimeter 0.0470 ft2
Critical hydraulic radius 6.5232 in
Critical top width 1.0368 in
Specific energy 4.0000 in
Minimum energy 0.5252 ft
Froude number 0.2650 ft
Flow Condition 3 .6923
Su ercritica1
Figure 12 Drain Line Calculations-ALU North
3.4 Surface Drainage at South Side of SFR
Half of sub-area 1 and all of sub-area 5 drain into a vegetated Swale at the South sidE
of the single family residence.
A = 2801/43560 = 0.06AC
Q = 0.66*6.32*0.06 = 0.25cfs
Side Slopes = 2:1 (H: V)
S = 0.048
Channel Calculator
Given Input Data:
Shape
Solve for Advanced
Flowrate Depth of Flow
Slope 0.2500 cfs
Manning's n 0.0480 ft/ft
Height 0.0750
Bottom Width 12.0000 in
Left Radius 0. 0000 in
Right Radius 0.0000 in
Left Slope 0.0000 in
0.5000 ft/ft
Right Slope (V/H)
0.5000 ft/ft
Depth Computed Results: (V/H)
Velocity 3 .8797 in
Full Flowrate 1.1958 fps
Area 5.0771 cfs
Perimeter 2. 0000 ft2
Flow Area 53 .6656 in
Flow Perimeter 0.2091 ft2
Hydraulic Radius 17.3507 in
Top Width 1.7351 in
Percent 15.5189 in
Critical Information: 32 .3311 %
Critical Depth
Critical slope 2 .9967 in
Critical velocity 0.1903 ft/ft
Critical area 2.0043 fps
Critical perimeter 0.1247 ft2
Critical hydraulic radius 13 .4019 in
Critical top width 1.3402 in
Specific energy 11.9870 in
Minimum energy 0.3455 ft
Froude number 0.3746 ft
Flow Condition 0.5243
• Subcritical
Figure 13 Vegetated Swale Calculations -SFR South
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HYDROLOGY AND HYDRAULIC STUDY
Wilms Residence
4 REFERENCES AND ABBREVIATIONS
4.1 References
• San Diego County Hydrology Manual by Department of Public Works — Flood
Control Section, dated June 2003
• Grading Plans for Wilms Residence
• San Diego County Soils Interpretation Study, Hydrology Soil Groups — Runoff
Potential, Encinitas, Panel No 33, by DPLU 1969
4.2 Abbreviations
A Area
As Minimum surface area required for settlingarticles
ac Acres
COUNTY San Die o Count
C Runoff Coefficient
cfs Cubic Feet per second
d Depth
D Duration
DPLU De artment of Planning and Land Use
DPW De artment of Public Works
F.S. Factor of safety
H Hei ht
l Rainfall Intensit
in/hr Inches er hour
L Len th
P24 Twent four hour precipitation
P6 Six hour reci itation
Q Dischar e
()AVE Average discharge
QD Desi n dischar a for detention basin sizin
QIN Inflow diczr-hnrrpn
QOUT Outflow dischar e
QPOST Post Construction Dischar e
QPRE Pre Construction Dischar e
SF Square Feet
SFR Single Family Residence
T. I Time of Concentration
Vs Settlin Velocit of smallest particle
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HYDROLOGY AND HYDRAULIC STUDY
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5 DECLARATION OF RESPONSIBLE CHARGE
I, hereby declare that I am the engineer of work for this project. That I have exercisE
responsible charge over the design of the project with respect to this study as define
in section 6703 of the Business and Professions Code, and that the design is
consistent with current standards.
I understand that the check of project drawings specifications, studies and reports by
the City of Encinitas is confined to a review only and does not relieve me, as eng nee
in responsible charge, of my responsibilities for project design.
David A. Ashcroft, PE C470 Expires 12/31105
Date
N AProjects\ADA_031014\Docs\Hydrology.doc
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F
F,
1
fill
It 0
0
>/
0
0
®m
GRAPHIC SCALE
too zoo 400
( IN FEET )
1 inch = 200 ft
DATE
No. 47024
EYE' 19n1A1F
ENGINEERING
CONSULTING
CrROUP 437 S. Highway 101, Suite 202 Solana Beach, California 92075
P: 858.259.4711 F: 858.259.5732 c .ecg=Lt m
HYDROLOGY NOTES
SUBAREA Tc (mins) 0 (cfs) V(fps)
1 5 1.72 0.47
Subarea = Hydrologic subarea
Tc = Time of concentraction for the subarea
Q = Runoff discharging from the subarea
V = Max. velocity of runoff discharging from subarea
KEYNOTES
OHYDROLOGIC SUBAREA 1 (0.46 AC)
LEGEND
--� FLOW DIRECTION FOR POTENTIAL RUNOFF
HYDROLOGIC SUBAREA BOUNDARY
PROPERTY LINE
s Residence
Hydrology Studi
1098 Hymettus Ave
Leucadia, CA 02024
Source: SANDAG GIS data, PLSS GIS
data, Record Information, San Diego
County Orthotopo 326 -1677 & 330 -1677
SHEET
1
OF 1 SHEETS
DATE
DESIGNER
Feb. 9, 03
D. Ashcroft
JOB N0,
DRAFTER
031014
D.A.A.
DRAWING ID.
CHECKER
'RCRIPTION
BY
DATE
H -1
D. Ashcroft
DATE
No. 47024
EYE' 19n1A1F
ENGINEERING
CONSULTING
CrROUP 437 S. Highway 101, Suite 202 Solana Beach, California 92075
P: 858.259.4711 F: 858.259.5732 c .ecg=Lt m
HYDROLOGY NOTES
SUBAREA Tc (mins) 0 (cfs) V(fps)
1 5 1.72 0.47
Subarea = Hydrologic subarea
Tc = Time of concentraction for the subarea
Q = Runoff discharging from the subarea
V = Max. velocity of runoff discharging from subarea
KEYNOTES
OHYDROLOGIC SUBAREA 1 (0.46 AC)
LEGEND
--� FLOW DIRECTION FOR POTENTIAL RUNOFF
HYDROLOGIC SUBAREA BOUNDARY
PROPERTY LINE
s Residence
Hydrology Studi
1098 Hymettus Ave
Leucadia, CA 02024
Source: SANDAG GIS data, PLSS GIS
data, Record Information, San Diego
County Orthotopo 326 -1677 & 330 -1677
SHEET
1
OF 1 SHEETS