HomeMy WebLinkAboutPD 16-22; WORTHING RESIDENCES; HYDROLOGY STUDY; DWG 498-3A, GR2016-0014; 2016-11-27/,''\
',)
, C)
(-~
' : )
HYDROLOGY REPORT
for
Worthing Residence
3443 & 3447 Madison Street
City of Carlsbad, California
PREPARED FOR:
Brooks Worthing
3443 & 3447 Madison Street
Carlsbad,Ca.92010
PREPARED BY:
Coastal Land Solutions
577 Second Street
Encinitas, CA 92024
(760) 230-6025
DATE:
September 6, 2016
Revised: November 27th, 2016
RECEIVE'.
DEC 21 2016
LAND DEVELOPivi::'.2
ENGINEERING
IZ-S"-/6
N
) -,
)
HYDROLOGY REPORT for 3443 & 3447 Madison Street
Executive Summary
Introduction
Existing Conditions
Proposed Project
TABLE OF CONTENTS
Summary of Results and Conditions
Conclusions
References
Methodology
Introduction
County of San Diego Criteria
Runoff coefficient determination
Hydrology Model Output
Pre-Developed Hydrologic Model Output
Post-Developed Hydrologic Model Output
Attachments
SECTION
1.0
1.1
1.2
1.3
1.4
1.5
1.6
2.0
2.1
2.2
2.3
3.0
3.1
3.2
Existing Condition Hydrology Map (pocket) A 1
Proposed Condition Hydrology Map (pocket) A2
Runoff Coefficients for Urban Areas A3
Maximum Overland Flow Length & Initial Time of Concentration A4
Soil Hydrologic Groups AS
Rainfall lsopluvials for 100 year Rainfall Event-6 hours A6
Rainfall lsopluvials for 100 year Rainfall Event-24 hours A7
Intensity Duration Design Chart AB
Average Velocity Chart for Overland Flow Time Travel A9
3443 & 3447 Worthing Residences 12/2/2016
• •
• • • • • • • • • • • • • •
• • •
HYDROLOGY REPORT for 3443 & 3447 Madison Street
1.0 EXECUTIVE SUMMARY
1.1 Introduction
This Hydrology Study, for 3437 & 3443 Madison Street, has been prepared to
analyze the hydrologic characteristics of the existing and proposed project site,
and determine the existing condition offsite hydrologic characteristics that are
conveyed through the proposed project site. This report intends to present the
methodology and the calculations used for determining the runoff from the project
site in both the pre-developed (existing) conditions and the post-developed
(proposed) conditions, as well as the offsite areas, produced by the 100 year 6
hour storm .
1.2 Existing Conditions
The proposed project property is located east of Coast Highway 101 , West of
Highway 5, north of Tamarack Avenue, and is located on the west side of
Madison Street, in the city of Carlsbad, as shown on the vicinity map and aerial
shown below .
Vicinity Map
3443 & 3447 Worthing Residences 12/2/201 6
• • • • • •
• • • • • • • • • • • • •
• • •
•
• •
HYDROLOGY REPORT for 3443 & 3447 Madison Street
Aerial Map
The existing site is two 0.08 acre (3,500sf) residential lots with a single family
residence. In addition to the existing residential structure, the site currently
consists of one driveway, wooden fences, and miscellaneous other hardscape.
Existing impervious surface area on the site is 1,988 sf. The percentage of
existing impervious surface on the site is 28%.
Drainage from the existing site is primarily conveyed in an easterly to westerly
direction, and sheet flows across the property. This drainage discharges west
into to a paved Alley .
3443 & 3447 Worthing Residences 12/2/2016
·./
/ --"\
\j
·,
)
•\
' )
HYDROLOGY REPORT for 3443 & 3447 Madison Street
1.3 Proposed Project
The intent of this project is to remove the entire existing single family residence
and grade two building pads, build two new single family residences, one on
each lot, construct concrete driveway, sidewalks, vegetated drainage swales,
and install new water and sewer services.
The proposed impervious surface area on the site is 4,497 sf. The percentage of
proposed impervious surface on the site is 64%.The proposed increase in
impervious surface is 2,509 sf, a 126% increase.
The drainage from the proposed development will be facilitated by overland
sheet flow and vegetated drainage swales. The vegetated drainage swale will
allow infiltration, volume reduction, detention, and treatment of storm water runoff
and other landscape and irrigation runoff. Vegetated swales at the westerly side
of the property will allow storm water to slow and infiltrate rather than flow quickly
off the site. Runoff from the site discharges west into the paved alley.
A runoff coefficient for Medium Density Residential will be used to determine the
proposed runoff for a future residential building development.
1.4 Summary of Results
Hydrologic analysis of the pre-developed and post-developed conditions of the
proposed project site is included in this report as section 3.1 and 3.2 respectively.
The hydrologic analysis is used in this report to approximate a peak flow at an
assumed point of discharge in the existing condition, to quantify a pre and post
developed condition peak flow. This assumption is made to develop a model that
generates conservative peak flows to ensure that the storm drain system will be
capable of safely conveying stormwater. The following summarizes the peak
discharges at three points of discharge that resulted from performing hydrologic
analysis of the project site in both the proposed developed and existing condition:
Point of Existing Conditions Developed Conditions
Discharge Q100 Tc AREA 0100 Tc AREA
(cfs) (min.) (acres) (cfs) (min.) (acres)
West 0.50 7.45 0.17 0.63 7.52 0.17 (Paved Alley)
The project site hydrologic models for both the pre-and post-developed
conditions encompass a total area of 0.08 acres. Evaluating the two models, the
proposed development will increase the amount of runoff from the project site by
0. 13 cfs or 26%. This increase is based on having a two single family building
residences, driveway, and hardscape areas.
3443 & 3447 Worthing Residences 12/2/2016
,_)
~ .)
" ,_j
HYDROLOGY REPORT for 3443 & 3447 Madison Street
1.5 Conclusions
As stated in section 1.4, the project site hydrologic models for both the pre-and
post-developed conditions encompass a total area of 0.17 acres. Evaluating the
two models, the proposed development will increase the amount of runoff from
the project site by 0.13 cfs or 26%.
The increase in runoff will be mitigated by creating vegetated drainage swales
along the side yards, and westerly side of the site. The required detention volume
is V= 0.13 cfs x (60 s/min) x 7.52min (Tc) = 58 cubic feet. The vegetated swales
will allow infiltration and volume reduction by adding a gravel drainage layer
underneath the swale. Total proposed length is 280' feet long x 1' minimum
width, with a 1' thick gravel layer beneath the vegetated swale. Using a 30% void
ratio the approximate detention volume of the gravel layer is 280'x1 'x1 'x0.30 = 84
cubic feet.
Drainage from the proposed residence is directed into vegetated swales prior to
discharge off site. The vegetated swales will allow for storm water, infiltration,
volume reduction, and treatment. The vegetated swale will treat runoff from
impervious hardscape and building surfaces. Based on the calculation in section
3.3, proposed and existing storm drain facilities can handle the runoff.
It is anticipated that the proposed storm drain system will maintain the historic
discharge locations of the existing drainage patterns. The proposed drainage
system will safely convey the entire 100-year peak flow generated by onsite
runoff.
1.6 References
"San Diego County Hydrology Manual", revised June 2003, County of San Diego,
Department of Public Works, Flood Control Section.
"San Diego County Stormwater Urban Mitigation Plan (SUSMP)", revised August
2012, County of San Diego.
3443 & 3447 Worthing Residences 12/2/2016
/ '\ (j
\. ,)
\ j
HYDROLOGY REPORT for 3443 &3447 Madison Street
2.0 METHODOLOGY
2.1 Introduction
The hydrologic model used to perform the hydrologic analysis presented in this
report utilizes the Rational Method (RM) equation, Q=CIA. The RM formula
estimates the peak rate of runoff based on the variables of area, runoff
coefficient, and rainfall intensity. The rainfall intensity (I) is equal to:
1 = 7.44 x P6 x o-0-645
Where:
I = Intensity (in/hr)
P6 = 6-hour precipitation (inches)
D = duration (minutes -use Tc)
Using the Time of Concentration (Tc), which is the time required for a given
element of water that originates at the most remote point of the basin being
analyzed to reach the point at which the runoff from the basin is being analyzed.
The RM equation determines the storm water runoff rate (Q) for a given basin in
terms of flow (typically in cubic feet per second (cfs) but sometimes as gallons
per minute (gpm)). The RM equation is as follows:
Q=CIA
Where:
Q= flow (in cfs)
C = runoff coefficient, ratio of rainfall that produces storm water
runoff (runoff vs. infiltration/evaporation/absorption/etc)
I = average rainfall intensity for a duration equal to the Tc for the
area, in inches per hour.
A = drainage area contributing to the basin in acres.
The RM equation assumes that the storm event being analyzed delivers
precipitation to the entire basin uniformly, and therefore the peak discharge rate
will occur when a raindrop, which falls at the most remote portion of the basin,
arrives at the point of analysis. The RM also assumes that the fraction of rainfall
that becomes runoff or the runoff coefficient C is not affected by the storm
intensity, I, or the precipitation zone number.
In addition to the above Rational Method assumptions, the conservative
assumption that all runoff coefficients utilized for this report are based on type "D"
soils.
3443 & 3447 Worthing Residences 12/2/2016
()
·.)
/ "'\
( _)
( 1 .. /
\ ___ ;
/' . )
HYDROLOGY REPORT for 3443 & 3447 Madison Street
2.2 County of San Diego Criteria
As defined by the County Hydrology Manual dated June 2003, the rational
method is the preferred equation for determining the hydrologic characteristics of
basins up to approximately one square mile in size. The County of San Diego
has developed its own tables, nomographs, and methodologies for analyzing
storm water runoff for areas within the county. The County has also developed
precipitation isopluvial contour maps that show even lines of rainfall anticipated
from a given storm event (i.e. 100-year, 6-hour storm).
One of the variables of the RM equation is the runoff coefficient, C. The runoff
coefficient is dependent on the percent of impervious surface, land use, and soil
type, and the County of San Diego has developed a table of Runoff Coefficients
for Urban Areas to be applied to basin located within the County of San Diego.
The table categorizes the land use, the associated development density (dwelling
units per acre) and the percentage of impervious area. Each of the categories
listed has an associated runoff coefficient, C, for each soil type class.
The County has also illustrated in detail the methodology for determining the time
of concentration, in particular the initial time of concentration. The County has
adopted the Federal Aviation Agency's (FAA) overland time of flow equation.
This equation essentially limits the flow path length for the initial time of
concentration to lengths of 100 feet or less, and is dependent on land use and
slope.
2.3 Runoff Coefficient Determination
As stated in section 2.2, the runoff coefficient is dependent on percent
impervious surface, land use, and soil type, and the County of San Diego has
developed a table of Runoff Coefficients for Urban Areas to be applied to basin
located within the County of San Diego. Table 3-1, included in the appendix,
categorizes the land use, the associated development density (dwelling units per
acre) and the percentage of impervious area.
The total number of dwellings proposed is 2, and the total developed lot area is
roughly equal to 0.16 acres. The dwelling unit per acre (DU/A) ratio is equal
12.44 DU/A which corresponds to Medium Density Residential DU/A of 14.5 or
less on table 3-1. Assume soil type is D, the runoff coefficient is 0.63.
For the both the existing and proposed development on site conditions, a
weighted C value is determined by the percentage of impervious and pervious
surfaces. The runoff coefficient of 0.90, for impervious surface, and 0.45 for
pervious surface are used.
3443 & 3447 Worthing Residences 12/2/2016
I r )
/ '\, < )
,)
/ '" ', .. )
( \ j
,,..-__,\
')
/ ' )
HYDROLOGY REPORT for 3443 & 3447 Madison Street
3.0 Hydrology Calculations
3.1 Pre-Developed Hydrology Calculations
SITE RUNOFF COEFFICIENT (DEVELOPED):
C= 0.63 (Table 3-1)
SITE RUNOFF COEFFICIENT (WEIGHTED):
C = 0.90 (Area impervious)+ 0.45 (Area pervious)
(Total Lot Area)
C= 0.90 (1,988 s.f.) + 0.45 (5,012 s.f.)
7,000 s.f.
C=1,789 s.f.+ 2,255 s.f.
7,000 s.f.
C= 0.58
Flow across initial sub area A nodes 3 to 2:
C= 0.58
A= 0.09 acres
L= 80 ft
S = (52.90-51.30)/80 = 2%
Ti= 6.5 min. (Table 3-2)
1100 = 5.58 in/hr
Onode2 = CAI = (0.58)(0.09)(5.58) = 0.29 cfs
Flow across sub area B nodes 2 to 1:
A=0.08 acres
L= 71ft
S = (51.30-49.65)/71 = 2.3%
V = (Grass Swale) = 1.25 ft/s
T(flow) = (71ft / 1.25 ft/s)/ 60 s/m = 0.95 min
Tc= Ti+ T(grass swale) = 6.5 min.+ 0.95 min.= 7.45 minutes
3443 & 3447 Worthing Residences 12/2/2016
,·-" ' I /
)
\
'j
HYDROLOGY REPORT for 3443 & 3447 Madison Street
1100 = 5.11 in/hr
Onode1 = [CAa + CAb] 1100 = [0.58 (0.09) + 0.58(0.08)] 5.11
Onode1 = 0.50 cfs
3443 & 3447 Worthing Residences 12/2/2016
I~\
j
.·· .'i . /
HYDROLOGY REPORT for 3443 & 3447 Madison Street
3.2 Developed Condition Hydrology Calculations
SITE RUNOFF COEFFICIENT (DEVELOPED):
C= 0.63 (Table 3-1)
SITE RUNOFF COEFFICIENT (WEIGHTED):
C = 0.90 (Area impervious)+ 0.45 (Area pervious)
(Total Lot Area)
C= 0.90 (4,497 s.f.) + 0.45 (2,503 s.f.)
7,000 s.f.
C=4,047 s.f. + 1,126 s.f.
7,000 s.f.
C= 0.73
Flow across initial sub area A, nodes 3 to 2:
C= 0.73
A= 0.09 acres
L= 80 ft
S = (53.00-51.50)/80 = 1.8%
Ti = 6.68 min. (Table 3-2)
1100 = 5.48 in/hr
Onode2 = CAI = (0. 73)(0.09)(5.48) = 0.36 cfs
Flow across sub area B nodes 2 to 1 :
A=0.08 acres
L= 71ft
S = (51.50-49.65)/71 = 2.6%
V = (Grass Swale) = 1.40 ft/s
T(flow) = (71ft / 1.25 ft/s)/ 60 s/m = 0.84 min
Tc= Ti+ T(grass swale) = 6.68 min.+ 0.84 min.= 7.52 minutes
1100 = 5.08 in/hr
3443 & 3447 Worthing Residences 12/2/2016
/ \ ' )
/\ \)
HYDROLOGY REPORT for 3443 & 3447 Madison Street
Onocte1 = [CAa + CAb] 1100
= [0.73 (0.09) + 0.73(0.08)] 5.08
Onocte1 = 0.63 cfs
3443 & 3447 Worthing Residences 12/2/2016
)
San Diego County Hydrology Manual
Date: June 2003
Table3-1
Section:
Page;
RUNOFF COEFFICIENTS FOR URBAN AREAS
Land Use Runoff Coefficient "C"
So.ilT e
NRCS Elements Count Elements % IMPI:."R. A 8
Undisturbed Natural Terrain (Natural) Permanent Open Space o• 0.20 0.25
Low Density Residential (LOR) Residential, J ,0 DUI A or less JO 0.27 0.32
Low Density Residential (LOR) Residential, 2.0 DU/A or less 20 0.34 0.38
Low Density Residential (LDR) Re..-tidential, 2.9 DU/A or less 25 0.38 0.4!
Medium Density Residential (MDR} Residential, 4.3 DU/ A or less 30 0.41 0.45
Medium Density Residential (MOR) Residential, 7.3 DU/A or ks5 40 0.48 0.51
Medium Density Residential (MOR) Residential, !0.9 DU/A or less 45 0.52 0.54 --111~ f~ -llfi)
High Density Residential {HDR) Residential, 24.0 DU/ A or less 65 0.66 0.67
High Density Residential (HOR) Residential, 43.0 DU/ A or less 80 0.76 0.77
Commercial/Industrial (N. Com) Neighborhood Commercial 80 0.76 0.77
Commercialilndustrial (G. Com) General Commercial 85 0.80 0.80
Commerciali!ndustrial (O.P. Com) Office Professional/Commercial 90 0.83 0.84
Commercial/lndustrial (Limited l.) Limited lndustl'ial 90 0.83 0.84
Commercialilndustrial General l. General Industrial 95 0.87 0.87
C
0,30
0.36
0.42
0.45
0.48
0.54
0.57 -0.69
(L78
0.78
0.81
0.84
0.84
0.&7
3
6of26
D
0.35
Ml
0A6
0.49
0.52
0.57
0.60
0.71
0.79
0.79
0.82
0.85
0.85
0.87
*The values as'SOciated with 0% impervious muy be used for direct calculation of the runoff coefficient as described in Section 3.l .2 (representing the pervious runoff
coefficient, Cp, for the soil type), or for areas that will remain undisturbed in perpetuity. Justification must be given that the area will remain natural forever (e.g., the area
is located in Cleveland National Forest).
DU/ A = dwelling units per acre
NRCS = National Resources Conservation Service
3-6
A3
('\
'"___)
i \
' )
San Diego County Hydrology Manual
Date: June 2003
Section:
Page:
3
12 of26
Note that the Initial Time of Concentration should be reflective of the general land-use at the
upstream end of a drainage basin. A single lot with an area of two or less acres does not have
a significant effect where the drainage basin area is 20 to 600 acres.
Table 3-2 provides limits of the length (Maximum Length (LM}) of sheet flow to be used in
hydrology studies. Initial Ti values based on average C values for the Land Use Element are
also included. These values can be used in planning and design applications as described
below. Exceptions may be approved by the "Regulating Agency" when submitted with a
detailed study.
Table 3-2
MAXIMUM OVERLAND FLOW LENGTH (LM)
& INITIAL TIME OF CONCENTRATION Ti _...._,._-=--.------,
Element* DU/ .5% 1%
Acre LM T1 LM Ti Ti
Natural 50 13.2 70 8.7 100 6.9
12.2 70 8.0 100 6.4
70 100 5.8
70 5.6
70 5.3
65 80 4.8
HDR 2.7
N.Com 2.7
G.Com
O.P./Com
Limited I.
General I.
*See Table 3-1 for more detailed description
3-12
•
• •
•
• •
33•
33°15"
33'00'
32°4'5'
32°30'
i. s
0
('I
(II
o> ?
~
~ ~ i t ~ ~ ~
<n t : ; ~ ~ ~
County of San Diego
Hydrology Manual 33'30'
• Soil Hydrologic Groups
Legend
Soll Groups
D °""'f>A -0,...,.8
CJ -c I D -0 CJ -...inod ~ CJ OOlaU-
I ~ ::,
'<
DPW S--gGIS •GIS ~ w...~s-n..._.,,-.r
N --·~-~,.--.--* ·--.. --~---·----..--0......,-...... -======-..:::.=-.:--------------·---32°30' s
3 0 3 MIios ~
A!>
)
33•30e---• ~--FF==;?<~,_.__-+-----·+-j -----·i-, -------+-----33"30'
i Riv~m;ide .County ....... ..,,,_~.,._...,..~~-----~5~ ~--
2.5
32•45• -----+---------;
---,;1--.--------..... ;----32"30'"
)
County of San Diego
Hydrology Manual
Rairifall Isopluvials
!_00 Ye.ar Rainfall Event-6 Hours
r-==··-~sopluvial (ioches} L ______ _
Ab
4.0
32'30'
County of San Diego
Hydrology Manual
Rainfall Isopluvials
100 Year Rainfall Eveot • 24 H~.!!r!,
[ ........ ~opluvial (inohell)
IS C~&
N ~~·~=~
E~~~:f:--_""'*"*._-~----....-__,-,.....,i,, __ _
3 0 3Mllea ~
7
lntensity•Duration Design Chart • Template
Oimctions for Application:
(1} From procipitalion maps determine 6 hr and 24 hr amounts
for :he selaclad frequency. These mapsaro included in the
County Hydrology Manual (10, 50, and ·100 yr maps included
in lM Design and Procedure Manual).
(2) Ad.1ust 6 hr preclpi!ation (if necessary) so that It is within
the range of 45% to 65'.Y, of the 24 hr precipitation (not
applk;aple \o Desert).
(3) ?!ot 6 hr pracipjtation on the righl side of the ell art
(4) Draw a line through the point parallel to !he plotted lines.
{5) This line is the intensity-duration curve tor !he location
being analyzed.
Application Form:
(a) Selected frequency ~._QQ yeor
(b)P62.5,_in.,P24 z 4.0 ,~" _62_ %!2)
24 tel Adjusted P6(Z) = m,
(di ix"' __ ,, min.
(e) I= in.lhr.
Nole: This chart rn~laces 1110 fntensity-Ourat1on-Frequency
ourves used since 1965,
AS
,--'\
' ' )
30
20
--;ft.
-;. 10 t:===t:====F=t:=;::::::t:::*=t=!~
Q.
0
"ii f 5 >---+---+---+-
:,
0
:: 3 ~ (CJ
~ 2 +-----1'---
0.5 .____._..__.___._......._ ................................. ~.----'-_..._
0.1 0.2 0.3 0.5 1 2 3
velocity (ft/sec)
5 10 20
Reprinted from SCS TR-55-1975. TR-55-1986 c~r1tains a simi-
lar graph for shallow-concentrated flow over paved and unpaved
surfaces, but it does not contain this particular graph.
Figure 20 .. 4 SGS Average Velocity Cha.rt for Overland Flow
Travel Time
9
GRAPHIC SCALE 1 '= 10' -~---~io,o-~1111111111~1---1--111111-,
0 10 20
q,~ COASTAL LAND SOLUTIONS, INC. it;l,~ '5"/7 SEllNl STIEET .. OCINIT AS. CA 92024
PH (700) 230-£025 FAX (700) 230-6026
CLS#1399
30
11
j
I
1
;
1
>-I
I
w ,, .....J .....J
<(
;
I
1
' 1
I
I ' ,,
I i
I I
EXISTING CONDITION HYDROLOGY MAP
I " I 11, I I II p
! ]l 1
1
1 ii : i
I ___ i_i! '1· I ' Ill :I I / L _______________ ........ ··--· ··1 ... ------·-·--·····------__ ; I; I
-----><---J\-x .... -,.--~~-x ----x----)<---1-----·--x --------·---x ·-------x ------11 •
LEGEND
ITEM
HYDROLOGY NODE
SUB AREA NAME
FLOW PATH
SUB-BASIN BOUNDARY
SUB-BASIN AREA
PROPERTY BOUNDARY
PROPOSED CONTOURS
EXISTING CONTOURS
J,
[f)
(D I\ ... /1 ·---L---11:·-s-=-2-i:·-G-R_A_ss---sw_A_L_E _______ /·-------@----.:-------------------'-
I \ EX=A9.65 \ EX=51.30 , \ , : ·r , I 1
I \, \ i I I I ! \ s, l~ I )( i I I
\ ·, .• _ '" i r"--·---·· -------i I I
I ,. -\ ! !I("-....... I I : I l IAREA B = 3, 526 sf (O. OBac) I [Af[EA !'_
1
-\4, OOOsf (0. 09a:cI]
I \ i I I /// ------------------------------'··--____ T _________ l ______ . __ l ___ L __________ . _____ -------------r ........ .
/I I 1/ i :
/ \ I ri : :
,/ 1' ' LID-~~ r···-----t--------1 f>
I / I r·-------· ,----·····------... ! !
1-w
[fJ w g:
Cl)
z 0 Cl)
0
[f) <(
:::E
I/ "~-------------------------·--_______ L ___ ------·-------r-··-·· ............ .. ,:y-t _/ r ,;c, I ! i I 3:
1 --><---X ---X -----11_ _____ X ------X --------X -----· X ->< ------------· X ---··->~ -~~----·"·-->< -..... --··-·-... >< ... _b~·z··,~,,:.::::.::,-·,r..,-~-~--~ r'~~i\ ... , .----1 --··-h·--, _ --------·--... :--~----11'i ·------t-\'I ___ _
)'-'' •.',\ 1\\',1, ' I •
[f)
X 1·· 1 \, ,.__:_/ I , : I i ! :
\
I
\, ,,,
I \1 ', I r
SYMBOL
0
0
---···--·
1024 acl
---255,---
----·-·-255---·--
Al
GRAPHIC SCALE 1"=10'
- - - I l ___ ~I
0 10 20 30
q,~ COASTAL LAND SOLUTIONS, INC. Cl~ 577 iElNl STIHT OCINITAS. CA 92024 F'ri (700) 230-6025
FAX (760) 2.»-1i026
CLS#1399
I
>-w
...J ...J
<(
l
I 1
I
I
I
' I I
1
'
1
:
!
' ,!
I :
PROPOSED CONDITION HYDROLOGY MAP
,1
Ii ii ' ii I ' I
, 11 i 111 ! i I
/ _____ ---------_____________ 1 J Jj 1 11 I : : 'f
w--x------&.-x----------x-----x x ::<---x---x -x ---x . ·-;--··--:---;<~:-=----::~. ;,,--· JI 11!~ : ; 1
(D ,________ / ···-L--1-1:·-s=-2-:2-%.-GR-As_s_s_w_ALE---···/--···--f-G=~~ \ ···---··· ··· \L;,;so. s=Ei. 1%, GRASS swALE ··· J:·--/0 0~~ --i-:--, ---
1
----,i -·---
'
_.\'""\ ___ Ex_=_A..,.l~---6-5----1, i I \ FS-51. 26 \ . r---·-:-·r------~' 1~ FS=~3:. 00 'f '"
11 . 7 i \,,_ ! \ J I I i i I '
: v,,________ ! ~\ r-------·t~-··1-------r , i : l ~ L
11 ,--LJ::=:::u:::-::::-:::=:::::t===========:l·J---1·-1·-----s-----J g:
\
\
I '
I
.
I
I
J ,
/
I
I
I
I
I
./ ,
,/
I _, .
I ,
'
' ,.
[ __ -_. -~--
I
'
.,-;
'
,. '
· IAREA B = 3, 526 ~f 1 (0. OBac) I
I ,
I '·
I I ' I I I'
/( ;
, I I I. . . . ----~--L _____ __.,:.:....._ .... ,_J,.;,.,,;J~...1""1...l.J .• L . .1 .... ...i-·j...:...;...:i.;i_J __ ,.,.; __ ___
' ___ ,!
--x----x-----X 1-·--···><-----x---x--
I 111 . II /-Vl
'----·--··r··-f-~:~~:-·-A-~·-::·o-oo:~·-;o.~~~c) I ! 11' ii : : ·( ~
J -',-_...rt==::11--1 i ! ·-//i1 : : I ~
I : ·1-T--i~------II , 1 ' (}) ;i
' ---
x----
mr~ ! I 1------_r~--------1/ I t;
I : I r·-----. ------[2~ • I / :
I I I I I :k --}j< I! rJJ
>< -. J -~ -· X ---··-LF\f _, c----~:::::-~ I I : I :<:
L
-x -
\\, ·: n i I I
I ' '· I ' ' ' I I ,\ \ ' I
"\ , I r----------~----------
' '
1
[>(
I
i I !1 1 1
I~> I ! ! I! ! j I f~J \ r.)1·1· I ''11 I ! I I \ -. I . I I I \ : : , ! I !
\ v-:i
\
\i
LEGEND
ITEM
HYDROLOGY NODE
SUB AREA NAME
FLOW PATH
SUB-BASIN BOUNDARY
SUB-BASIN AREA
BUILDING FOOTPRINT
PROPOSED CONCRETE HARDSCAPE
PROPERTY BOUNDARY
PROPOSED CONTOURS
EXISTING CONTOURS
SYMBOL
®
0
---··--·
!024 acl
.. , I
---255,---
----255---~-
A2