el paso county, colorado · and surveyors, dated may 2001, and thus shall not adversely affect the...
TRANSCRIPT
1
FINAL DRAINAGE LETTER
FOR
LOT 48, HIGH FOREST RANCH FILING NO. 2
EL PASO COUNTY, COLORADO
AUGUST 2017
Prepared for:
Alan D. Butterfield
4324 Candlewood Lane
Port Orange, FL 32127
Prepared by:
20 Boulder Crescent, Suite 110
Colorado Springs, CO 80903
(719) 955-5485
Project #70-048 PCD Project #CDR-17-001
2
FINAL DRAINAGE LETTER
FOR
LOT 48, HIGH FOREST MEADOWS FILING NO. 2
DRAINAGE PLAN STATEMENTS
ENGINEERS STATEMENT
The attached drainage plan and report was prepared under my direction and supervision and are correct to the best of my knowledge and belief. Said drainage report has been prepared according to the criteria established by the County for drainage reports and said report is in conformity with the applicable master plan of the drainage basin. I accept responsibility for any liability caused by any negligent acts, errors of omission on my part in preparing this report.
____________________________________
Virgil A. Sanchez, P.E. #37160 For and on Behalf of M&S Civil Consultants, Inc
DEVELOPER’S STATEMENT
I, the developer have read and will comply with all the requirements specified in this drainage report
and plan. BY:___________________________________
TITLE:__________________________
DATE:__________________________
ADDRESS: Alan D. Butterfield 4324 Candlewood Lane Port Orange, FL 32127
EL PASO COUNTY'S STATEMENT
Filed in accordance with the requirements of El Paso County Land Development Code, Drainage Criteria Manual Volumes 1 and 2, and the Engineering Manual, as amended.
BY:______________________________ DATE:___________________ Jennifer Irvine, P.E.
County Engineer
CONDITIONS:
3
FINAL DRAINAGE LETTER
FOR
LOT 48, HIGH FOREST MEADOWS FILING NO. 2
TABLE OF CONTENTS
PURPOSE 4
GENERAL LOCATION AND DESCRIPTION 4
SOILS 4 HYDROLOGIC CALCULATIONS 4
HYDRAULIC CALCULATIONS 5
FLOODPLAIN STATEMENT 5
DRAINAGE CRITERIA 5 EXISTING DRAINAGE CONDITIONS 5
PROPOSED DRAINAGE CONDITIONS 5 EROSION CONTROL 6 CONSTRUCTION COST OPINION 6 DRAINAGE & BRIDGE FEES 6
SUMMARY 6
REFERENCES 7
APPENDIX
Vicinity Map
Soils Map
FIRM Panel
Hydrologic Calculations
Hydraulic Calculations Grading Erosion Control Plan
Drainage Maps
4
FINAL DRAINAGE LETTER
FOR
LOT 48, HIGH FOREST MEADOWS FILING NO. 2
PURPOSE This document is intended to serve as the Final Drainage Letter for Lot 48, of High Forest Meadows
Filing No. 2. The purpose of this document is to identify and analyze the on and offsite drainage patterns
and to ensure that post development runoff is routed through the site safely and in a manner that satisfies
the requirements set forth by the El Paso County Drainage Criteria Manual. The proposed principal use
for the site consist a single family residential home site.
GENERAL LOCATION AND DESCRIPTION Lot 48, of High Forest Meadows is located in the east half of Section 26, Township 11 South, Range 66 West of the 6th P.M. in El Paso County, Colorado. The site is bound on the northwest by the existing Open Sky Way asphalt roadway. To the east by Lots 49 and 50 of High Forest Meadows Filing No. 2, both are currently vacant. To the west by Lots 45, 46 and 47 of High Forest Meadows Filing No. 2, all are developed with a residential single family home on each lot. To the south by a vacant parcel of land that currently has a single family residential home site and several outbuildings. The site lies within the East Cherry Creek Drainage Basin. Flows from this site are tributary to Black Squirrel Creek, which travels onto City of Colorado Springs land (Northgate). Then crosses under I-25 and then continues across U.S.A.F.A property. Lot 48, of High Forest Meadows Filing No. 2 consists of 15.96 acres in which is presently undeveloped. The majority of the site is characterized by rolling hills with natural valleys and swales drainage southeasterly of the site. Ground cover is fair with the primarily vegetation consisting of native grasses with a few Ponderosa pine trees.
SOILS
Soils for this project (see soils map provided in the appendix) consist of #41 Kettle gravely loamy sand, #67, Peyton sand loam, and #92 Tomah-Crowfoot loamy sands. All soils are characterized as Hydrologic Type "B"soils as mapped by S.C.S. in the "Soils Survey of El Paso County Area".
HYDROLOGIC CALCULATIONS This site is subject to the findings within the MDDP for High Forest Ranch prepared by JR Engineering,
date June 2000, and by the Final Drainage Report for High Forest Ranch Filing No. 2 & No. 3 prepared
by Classic Consulting Engineers and Surveyors, dated May 2001. Hydrologic calculations were
performed using the El Paso County and City of Colorado Springs Storm Drainage Design Criteria
manual and where applicable the Urban Storm Drainage Criteria Manual. The Rational Method was
used to estimate stormwater runoff anticipated from design storms with 5-year and 100-year recurrence
intervals.
5
HYDRAULIC CALCULATIONS Hydraulic calculations were estimated using the Manning's Formula and the methods described in the El
Paso County and City of Colorado Springs Storm Drainage Design Criteria manual. The relevant data
sheets are included in the appendix of this report.
FLOODPLAIN STATEMENT
According to the Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map (FIRM)
Panel No. 08041C0325 F, effective date March 17, 1997, no portion of this site is located within a
floodplain.
DRAINAGE CRITERIA
This drainage analysis has been prepared in accordance with the current City of Colorado Springs/El
Paso County Drainage Criteria Manual. Calculations were performed to determine runoff quantities for
the 5-year and 100-year frequency storms for developed conditions using the Rational Method as
required for basins having areas less than 100 acres.
EXISTING DRAINAGE CONDITIONS
Lot 48, of High Forest Meadows Filing No. 2 consists of 15.96 acres in which is presently undeveloped.
The majority of the site is characterized by a few rolling hills with natural valleys and swales.
Vegetation is sparse, consisting of Ponderosa Pines and native grasses. A ridge line runs north to south
along the western portion of the property, directing runoff from 1.0 acres of the nearly 16.0 acres site to
the west, while the majority of the drainage is directed to the eastern boundary of the lot. Offsite runoff
impacting the subject site, reaches as sheet flow smaller local basins along the east and west perimeter,
and as concentrated flow from three existing corrugated metal culverts (21”, 24” and 30”) which convey
concentrated flow under Open Sky Way from portions of 4 larger residential lots and portions of
roadway located to the north of the site. As shown on the Existing Conditions Map provided in the
appendix drainage easements were previously provided across Lot 48, from the outfall of the 21 and 30”
CMPs, while no easement was provided from the 24” pipe. Runoff reaching the eastern boundary at
Design Points E3, E5, and E10 in the existing condition in the 100 year event is 36.3cfs, 8.2cfs, and
36.8cfs respectively, while runoff at the western discharge point at E4 is 2.3 cfs (100 year event).
PROPOSED DRAINAGE CHARACTERISTICS General Concept Drainage Discussion
Lot 48, of High Forest Meadows Filing No. 2 consists of a total of 15.96 acres in which is presently
undeveloped. The proposed site improvements shall consists of an approximately 4000 SF (footprint)
single family residence located near the northeastern corner of the site, outside of the preservation area.
A 12’ wide proposed impervious driveway (10,500 sq ft) and embankment will connect the proposed
residence to Open Sky Way (private roadway). The total site disturbance shall be approximately 7.10
acres. No import or export of dirt is anticipated. It should be noted that during the writing of this report
the actual driveway surface materials have not been determined at this time and will most likely be
constructed of concrete or asphalt.
6
With the exception of the noted improvements, the majority of the Lot 48’s natural topography and drainage patterns shall be left in its natural state. The proposed drainage improvements include a proposed 36” RCP pipe with a 36” FES at each end. A proposed 17’long x 14’ wide x 1.5’thick riprap apron (D50=9”) shall be recommended to be constructed at the outlet to slow discharge from the culvert. The purpose for the drainage improvements is to ensure the existing flow patterns continue on their natural course without hindrance. Runoff reaching the eastern boundary in the proposed condition at Design Points 3, 5, and 10 in the existing condition in the 100 year event is 36.7cfs, 8.5cfs, and 36.8cfs respectively, while runoff at the western discharge point at 4 is 2.3 cfs (100 year). The total impervious acreage for the subject site is approximately 0.33 acres. When divided across the 15.96 acres results in about 2% total site imperviousness. This is less than the average anticipated imperviously percentage provided in the drainage planning documents of 7 to 8%. As such the proposed development is in line with the development plan assumptions made within the approved MDDP for High Forest Ranch prepared by JR Engineering, date June 2000, and by the Final Drainage Report for High Forest Ranch Filing No. 2 & No. 3 prepared by Classic Consulting Engineers and Surveyors, dated May 2001, and thus shall not adversely affect the downstream development.
EROSION CONTROL
It is the policy of the El Paso County that we submit a grading and erosion control plan with the drainage
report. Proposed silt fence, vehicle traffic control, and concrete washout area are proposed as erosion
control measures.
CONSTRUCTION COST OPINION
Private Drainage Facilities NON-Reimbursable: Item Description Quantity Unit Cost Cost
1. 36" RCP 83 LF $124/LF $ 10,292.00 2. 36” RCP FES 2 EA $450/EA $ 900.00 3. D50= 9” RIP RAP 14 CY $98/CY $ 1,372.00
Total $ 12,564.00
DRAINAGE & BRIDGE FEES
No drainage fees are due as the site has been previously platted.
M & S Civil Consultants, Inc. (M & S) cannot and does not guarantee the construction cost will not vary from these opinions of probable costs. These opinions represent our best judgment as design professionals familiar with the construction industry and this development in particular. The above is only an estimate of the facility cost and drainage basin fee amounts in 2017.
SUMMARY The proposed development of Lot 48, of High Forest Ranch is in line with the development plan assumptions made within the approved MDDP for High Forest Ranch prepared by JR Engineering, date June 2000, and by the Final Drainage Report for High Forest Ranch Filing No. 2 & No. 3 prepared by Classic Consulting Engineers and Surveyors dated May 2001 and thus shall not adversely affect the downstream development.
7
REFERENCES
1.) "El Paso County and City of Colorado Springs Drainage Criteria Manual". 2.) "Urban Storm Drainage Criteria Manual"
3.) SCS Soils Map for El Paso County.
4.) Flood Insurance Rate Map (FIRM), Federal Emergency Management Agency, Effective date
March 17, 1997.
5.) "Final Drainage Report for High Forest Ranch Filing No. 2 and High Forest Meadows Filing No. 3, dated May 2001, by Classic Consulting Engineers & Surveyors, LLC.
6.) " MDDP for High Forest Ranch”, dated May 2001, by JR Engineering.
APPENDIX
VICINITY MAP
SOILS MAP
Soil Map—El Paso County Area, Colorado
Natural ResourcesConservation Service
Web Soil SurveyNational Cooperative Soil Survey
7/15/2017Page 1 of 3
4323
850
4323
900
4323
950
4324
000
4324
050
4324
100
4324
150
4324
200
4324
250
4323
850
4323
900
4323
950
4324
000
4324
050
4324
100
4324
150
4324
200
4324
250
522620 522670 522720 522770 522820 522870 522920
522620 522670 522720 522770 522820 522870 522920
39° 4' 2'' N10
4° 4
4' 1
9'' W
39° 4' 2'' N
104°
44'
5'' W
39° 3' 47'' N
104°
44'
19'
' W
39° 3' 47'' N
104°
44'
5'' W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS840 100 200 400 600
Feet0 30 60 120 180
MetersMap Scale: 1:2,190 if printed on A portrait (8.5" x 11") sheet.
Soil Map may not be valid at this scale.
FLOOD PLAIN MAP
HYDROLOGIC CALCULATIONS
BASIN
TOTAL
AREA
TOTAL
AREA
AREA
C5
C100
AREA
C5
C100
AREA
C5
C100
C5
C100
(SF
)(A
cres
)(A
cres
)(A
cres
)(A
cres
)
EX
114
8784
.03.
420.
430.
900.
960.
060.
590.
702.
920.
080.
350.
190.
43
EX
217
9106
.04.
110.
430.
900.
960.
060.
900.
963.
630.
080.
350.
180.
42
EX
356
198.
01.
290.
160.
900.
960.
150.
900.
960.
980.
080.
350.
270.
49
EX
434
7007
.07.
970.
000.
900.
960.
000.
300.
507.
970.
080.
350.
080.
35
EX
544
480.
01.
020.
000.
900.
960.
000.
300.
501.
020.
080.
350.
080.
35
EX
615
1044
3.47
0.00
0.90
0.96
0.00
0.30
0.50
3.47
0.08
0.35
0.08
0.35
EX
741
4867
9.52
0.12
0.90
0.96
0.00
0.30
0.50
9.40
0.08
0.35
0.09
0.36
DE
VE
LO
PE
DU
ND
EV
EL
OP
ED
WE
IGH
TE
D
LO
T 4
8, H
IGH
FO
RE
ST
RA
NC
HE
XIS
TIN
G D
RA
INA
GE
CA
LC
UL
AT
ION
S(A
rea
Ru
nof
f C
oeff
icie
nt S
um
mar
y)
ST
RE
ET
S /
DE
VE
LO
PE
D
EX
741
4867
9.52
0.12
0.90
0.96
0.00
0.30
0.50
9.40
0.08
0.35
0.09
0.36
EX
810
370
0.24
0.12
0.90
0.96
0.00
0.30
0.50
0.12
0.08
0.35
0.48
0.65
EX
915
2487
3.50
0.00
0.90
0.96
0.00
0.30
0.50
3.50
0.08
0.35
0.08
0.35
EX
1019
1799
4.40
0.15
0.90
0.96
0.00
0.30
0.50
4.26
0.08
0.35
0.11
0.37
EX
1197
960.
220.
120.
900.
960.
000.
300.
500.
100.
080.
350.
520.
68
EX
1223
216
0.53
0.00
0.90
0.96
0.00
0.30
0.50
0.53
0.08
0.35
0.08
0.35
Cal
cula
ted
by:
Dat
e:C
heck
ed b
y:
CM
N7/
17/2
017
VA
S
MS
CIV
IL, I
NC
Lot 4
8 H
igh
For
est R
anch
(E
xist
ing)
700
487/
18/2
017
OV
ER
LA
ND
ST
RE
ET
/ C
HA
NN
EL
FL
OW
Tim
e of
Tra
vel (
Tt)
BASIN
AREA
TOTAL
C5
C100
C5
Length
Height
TC
Length
Slope
Velocity
Tt
TOTAL
I 5I 100
Q5
Q100
(Acr
es)
(ft)
(ft)
(min
)(f
t)(%
)(f
ps)
(min
)(m
in)
(in/
hr)
(in/
hr)
(c.f
.s.)
(c.f
.s.)
EX
13.42
0.19
0.43
0.19
100
59.
680
66.
6%3.
93.
513
.13.
76.
32.
59.
3
EX
24.11
0.18
0.42
0.18
100
78.
871
08.
3%4.
32.
711
.53.
96.
62.
911
.4
EX
31.29
0.27
0.49
0.27
100
87.
50
0.0%
0.0
0.0
7.5
4.6
7.7
1.6
4.9
EX
47.97
0.08
0.35
0.08
100
510
.880
53.
0%2.
65.
216
.03.
55.
92.
216
.5
EX
51.02
0.08
0.35
0.08
100
128.
151
02.
7%2.
53.
411
.53.
96.
60.
32.
3
EX
63.47
0.08
0.35
0.08
100
98.
943
06.
7%3.
91.
810
.84.
06.
71.
18.
2
EX
79.52
0.09
0.36
0.09
100
510
.785
07.
0%4.
03.
614
.33.
66.
03.
120
.6
EX
80.24
0.48
0.65
0.48
502
5.0
120
5.0%
3.4
0.6
5.6
5.0
8.4
0.6
1.3
EX
93.50
0.08
0.35
0.08
100
89.
345
04.
0%3.
02.
511
.83.
96.
51.
18.
0
EX
104.40
0.11
0.37
0.11
100
411
.352
56.
7%3.
92.
213
.63.
76.
21.
710
.1
EX
110.22
0.52
0.68
0.52
502
4.7
150
4.0%
3.0
0.8
5.5
5.0
8.4
0.6
1.3
EX
120.53
0.08
0.35
0.08
100
411
.70
0.0%
0.0
0.0
11.7
4.0
6.8
0.2
1.3
* In
tens
ity e
quat
ions
ass
umes
a m
inim
um tr
avel
tim
e of
5 m
inut
es.
Cal
cula
ted
by:
Dat
e:C
heck
ed b
y:
TO
TA
L F
LO
WS
VA
S
EX
IST
ING
DR
AIN
AG
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AL
CU
LA
TIO
NS
LO
T 4
8, H
IGH
FO
RE
ST
RA
NC
H
CM
N
Fro
m D
CM
Tab
le 5
-1
7/17
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7
INT
EN
SIT
Y *
(Are
a D
rain
age
Sum
mar
y)F
rom
Are
a R
unof
f Coe
ffic
ient
Sum
mar
y
Che
cked
by:
VA
S
MS
CIV
IL, I
NC
.Lo
t 48
Hig
h F
ores
t Ran
ch (
Exi
stin
g) 7
0048
7/18
/201
7
OV
ER
LA
ND
PIP
E /
CH
AN
NE
L F
LO
WIN
TE
NSI
TY
*T
OT
AL
FL
OW
S
DE
SIG
N P
OIN
TC
ON
TR
IBU
TIN
G B
ASI
NS
CA
5C
A10
0C
5L
engt
hH
eigh
tT
CL
engt
hSl
ope
Vel
ocit
yT
tT
OT
AL
Loc
atio
nI5
I 100
Q5
Q10
0
(ft)
(ft)
(min
)(f
t)(%
)(f
ps)
(min
)(m
in)
(in/
hr)
(in
/hr)
(c.f
.s.)
(c.f
.s.)
E1
EX
-10.
661.
4813
.13.
76.
32.
59.
3
E2
DP
E1,
EX
21.
393.
2213
.13.
76.
35.
220
.1
E3
DP
E2,
EX
3, E
X4
2.38
6.64
13.1
805
3.5%
2.8
4.8
17.9
3.3
5.5
7.7
36.3
E4
EX
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080.
3611
.53.
96.
60.
32.
3
E5
EX
60.
281.
2110
.84.
06.
71.
18.
2
E6
EX
70.
863.
4114
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66.
03.
120
.6
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DP
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55.
93.
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BA
SIN
EX
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c U
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USE
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Fro
m A
rea
Run
off C
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icie
nt S
umm
ary
Tim
e of
Tra
vel (
Tt)
(Bas
in E
X1
Tc
Use
d)
BA
SIN
EX
5 T
c U
SED
BA
SIN
EX
7 T
c U
SED
(Bas
in E
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Tc
Use
d)
LO
T 4
8, H
IGH
FO
RE
ST
RA
NC
HE
XIS
TIN
G D
RA
INA
GE
CA
LC
UL
AT
ION
S(B
asin
Rou
ting
Su
mm
ary)
BA
SIN
EX
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c U
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EX
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E8,
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110.
591.
7813
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814
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66.
02.
110
.7
E10
DP
E7,
DP
E9,
EX
9 1.
896.
7614
.956
03.
9%3.
03.
218
.03.
25.
46.
136
.8E
X12
Cal
cula
ted
by:
Dat
e:C
heck
ed b
y:V
AS
7/17
/201
7C
MN
BA
SIN
EX
10 T
c U
SED
(Bas
in E
X10
Tc
Use
d)
(DP-
7 T
c U
sed)
MS
CIV
IL, I
NC
.Lo
t 48
Hig
h F
ores
t Ran
ch (
Exi
stin
g) 7
0048
7/18
/201
7
Inte
nsi
ty*
Flo
wP
ipe
Siz
e
PIP
EC
ontr
ibu
tin
gP
ipes
/Des
ign
Poi
nts
Equ
ival
ent
CA
5
Equ
ival
ent
CA
100
Max
imu
mT
CI
5I
100
Q5
Q10
0
1DPE1
0.66
1.48
13.1
3.7
6.3
2.5
9.3
Exi
stin
g 18
" C
MP
2DPE2
1.39
3.22
13.1
3.7
6.3
5.2
20.1
Exi
stin
g 24
" C
MP
3DPE6
0.86
3.41
14.3
3.6
6.0
3.1
20.6
Exi
stin
g 30
" C
MP
4DPE8
0.47
1.63
13.6
3.7
6.2
1.7
10.0
Exi
stin
g 21
" C
MP
* In
tens
ity
equa
tion
s as
sum
e a
min
imum
trav
el ti
me
of 5
min
utes
.C
alcu
late
d by
:D
P -
D
esig
n P
oint
Dat
e:E
X -
E
xist
ing
Des
ign
Poi
ntC
heck
ed b
y:IN
T-
Inte
rcep
ted
Flow
fro
m D
esig
n P
oint
VA
S
LO
T 4
8, H
IGH
FO
RE
ST
RA
NC
HE
XIS
TIN
G D
RA
INA
GE
CA
LC
UL
AT
ION
S(S
torm
Sew
er R
outi
ng S
um
mar
y)
CM
N F
B-
Flow
By
from
Des
ign
Poi
nt7/
17/2
017
MS
CIV
IL, I
NC
Lot 4
8 H
igh
For
est R
anch
(E
xist
ing)
700
487/
18/2
017
PR
OP
OS
ED
DR
AIN
AG
E C
AL
CU
LA
TIO
NS
LO
T 4
8, H
IGH
FO
RE
ST
RA
NC
H
OV
ER
LA
ND
ST
RE
ET
/ C
HA
NN
EL
FL
OW
Tim
e of
Tra
vel (
Tt)
BASIN
AREA
TOTAL
C5
C100
C5
Length
Height
TC
Length
Slope
Velocity
Tt
TOTAL
I 5I 100
Q5
Q100
(Acr
es)
(ft)
(ft)
(min
)(f
t)(%
)(f
ps)
(min
)(m
in)
(in/
hr)
(in/
hr)
(c.f
.s.)
(c.f
.s.)
OS
13.42
0.19
0.43
0.19
100
59.
680
66.
6%3.
93.
513
.13.
76.
32.
59.
3
OS
24.11
0.18
0.42
0.18
100
78.
871
08.
3%4.
32.
711
.53.
96.
62.
911
.4
OS
31.29
0.27
0.49
0.27
100
87.
50
0.0%
0.0
0.0
7.5
4.6
7.7
1.6
4.9
A4.34
0.10
0.37
0.10
100
510
.637
53.
2%2.
72.
312
.93.
86.
31.
710
.1
OS
51.02
0.08
0.35
0.08
100
128.
151
02.
7%2.
53.
411
.53.
96.
60.
32.
3
B3.51
0.12
0.38
0.12
100
69.
838
53.
4%2.
82.
312
.13.
86.
51.
68.
6
C3.59
0.08
0.35
0.08
100
98.
943
06.
7%3.
91.
810
.84.
06.
71.
28.
5
OS
79.52
0.09
0.36
0.09
100
510
.785
07.
0%4.
03.
614
.33.
66.
03.
120
.6
OS
80.24
0.48
0.65
0.48
502
5.0
120
5.0%
3.4
0.6
5.6
5.0
8.4
0.6
1.3
D3.50
0.08
0.35
0.08
100
89.
345
04.
0%3.
02.
511
.83.
96.
51.
18.
0
OS
104.40
0.11
0.37
0.11
100
411
.352
56.
7%3.
92.
213
.63.
76.
21.
710
.1
OS
110.22
0.52
0.68
0.52
502
4.7
150
4.0%
3.0
0.8
5.5
5.0
8.4
0.6
1.3
OS
120.53
0.08
0.35
0.08
100
411
.70
0.0%
0.0
0.0
11.7
4.0
6.8
0.2
1.3
* In
tens
ity e
quat
ions
ass
umes
a m
inim
um tr
avel
tim
e of
5 m
inut
es.
Cal
cula
ted
by:
Dat
e:C
heck
ed b
y:
(Are
a D
rain
age
Sum
mar
y)F
rom
Are
a R
unof
f Coe
ffic
ient
Sum
mar
yT
OT
AL
FL
OW
S
VA
S
PR
OP
OS
ED
DR
AIN
AG
E C
AL
CU
LA
TIO
NS
CM
N
Fro
m D
CM
Tab
le 5
-1
7/17
/201
7
INT
EN
SIT
Y *
MS
CIV
IL, I
NC
.Lo
t 48
Hig
h F
ores
t Ran
ch (
Pro
pose
d) 7
0048
7/18
/201
7
BASIN
TOTAL
AREA
TOTAL
AREA
AREA
C5
C100
AREA
C5
C100
AREA
C5
C100
C5
C100
(SF
)(A
cres
)(A
cres
)(A
cres
)(A
cres
)
OS1
1487
84.0
3.42
0.43
0.90
0.96
0.06
0.59
0.70
2.92
0.08
0.35
0.19
0.43
WE
IGH
TE
D
LO
T 4
8, H
IGH
FO
RE
ST
RA
NC
HP
RO
PO
SED
DR
AIN
AG
E C
AL
CU
LA
TIO
NS
(Are
a R
un
off
Coe
ffic
ient
Su
mm
ary)
ST
RE
ET
S /
DE
VE
LO
PE
DD
EV
EL
OP
ED
UN
DE
VE
LO
PE
D
OS1
1487
84.0
3.42
0.43
0.90
0.96
0.06
0.59
0.70
2.92
0.08
0.35
0.19
0.43
OS2
1791
06.0
4.11
0.43
0.90
0.96
0.06
0.90
0.96
3.63
0.08
0.35
0.18
0.42
OS3
5619
8.0
1.29
0.16
0.90
0.96
0.15
0.90
0.96
0.98
0.08
0.35
0.27
0.49
A18
9142
.04.
340.
110.
900.
960.
030.
300.
504.
200.
080.
350.
100.
37
OS5
4448
0.0
1.02
0.00
0.90
0.96
0.00
0.30
0.50
1.02
0.08
0.35
0.08
0.35
B15
2694
.03.
510.
140.
900.
960.
060.
730.
813.
310.
080.
350.
120.
38
C15
6214
3.59
0.00
0.90
0.96
0.00
0.30
0.50
3.59
0.08
0.35
0.08
0.35
OS7
4148
679.
520.
120.
900.
960.
000.
300.
509.
400.
080.
350.
090.
36
OS8
1037
00.
240.
120.
900.
960.
000.
300.
500.
120.
080.
350.
480.
65
D15
2487
3.50
0.00
0.90
0.96
0.00
0.30
0.50
3.50
0.08
0.35
0.08
0.35
OS1
019
1799
4.40
0.15
0.90
0.96
0.00
0.30
0.50
4.26
0.08
0.35
0.11
0.37
OS1
197
960.
220.
120.
900.
960.
000.
300.
500.
100.
080.
350.
520.
68
OS1
223
216
0.53
0.00
0.90
0.96
0.00
0.30
0.50
0.53
0.08
0.35
0.08
0.35
Cal
cula
ted
by:
Dat
e:C
heck
ed b
y:
CM
N7/
17/2
017
VA
S
MS
CIV
IL, I
NC
Lot 4
8 H
igh
For
est R
anch
(P
ropo
sed)
700
487/
18/2
017
OV
ER
LA
ND
PIP
E /
CH
AN
NE
L F
LO
WIN
TE
NSI
TY
*T
OT
AL
FL
OW
S
DE
SIG
N P
OIN
TC
ON
TR
IBU
TIN
G B
ASI
NS
CA
5C
A10
0C
5L
engt
hH
eigh
tT
CL
engt
hSl
ope
Vel
ocit
yT
tT
OT
AL
Loc
atio
nI5
I 100
Q5
Q10
0
(ft)
(ft)
(min
)(f
t)(%
)(f
ps)
(min
)(m
in)
(in/
hr)
(in
/hr)
(c.f
.s.)
(c.f
.s.)
1O
S1
0.66
1.48
13.1
3.7
6.3
2.5
9.3
2D
P1,
OS2
1.39
3.22
13.1
3.7
6.3
5.2
20.1
2AD
P2,
OS3
, A2.
195.
4513
.147
53.
4%2.
82.
916
.03.
45.
87.
531
.3
Fro
m A
rea
Run
off C
oeff
icie
nt S
umm
ary
Tim
e of
Tra
vel (
Tt)
(Bas
in O
S1
Tc
Use
d)
LO
T 4
8, H
IGH
FO
RE
ST
RA
NC
HP
RO
PO
SED
DR
AIN
AG
E C
AL
CU
LA
TIO
NS
(Bas
in R
outi
ng S
um
mar
y)
BA
SIN
EX
1 T
c U
SED
BA
SIN
EX
Tc
USE
D
3D
P2A
, B2.
626.
7816
.037
03.
2%2.
72.
318
.33.
25.
48.
436
.7
4O
S5
0.08
0.36
11.5
3.9
6.6
0.3
2.3
5C
0.29
1.26
10.8
4.0
6.7
1.2
8.5
6O
S7
0.86
3.41
14.3
3.6
6.0
3.1
20.6
7D
P6,
D0.
983.
5614
.310
02.
0%2.
80.
614
.93.
55.
93.
521
.1
8O
S10
0.47
1.63
13.6
3.7
6.2
1.7
10.0
9D
P8,
OS1
10.
591.
7813
.610
01.
0%2.
00.
814
.43.
66.
02.
110
.7
10D
P7,
DP
9, O
S9
1.89
6.76
14.9
560
3.9%
3.0
3.2
18.0
3.2
5.4
6.1
36.8
OS
12
Cal
cula
ted
by:
Dat
e:C
heck
ed b
y:V
AS
7/17
/201
7C
MN
(DP2
A T
c U
sed)
BA
SIN
EX
5 T
c U
SED
BA
SIN
EX
6 T
c U
SED
BA
SIN
EX
7 T
c U
SED
(Bas
in O
S7
Tc
Use
d)
BA
SIN
EX
10 T
c U
SED
(Bas
in O
S10
Tc
Use
d)
(DP7
Tc
Use
d)
MS
CIV
IL, I
NC
.Lo
t 48
Hig
h F
ores
t Ran
ch (
Pro
pose
d) 7
0048
7/18
/201
7
Inte
nsi
ty*
Flo
wP
ipe
Siz
e
PIP
EC
ontr
ibu
tin
gP
ipes
/Des
ign
Poi
nts
Equ
ival
ent
CA
5
Equ
ival
ent
CA
100
Max
imu
mT
CI
5I
100
Q5
Q10
0
LO
T 4
8, H
IGH
FO
RE
ST
RA
NC
HP
RO
PO
SE
D D
RA
INA
GE
CA
LC
UL
AT
ION
S(S
torm
Sew
er R
outi
ng S
um
mar
y)
1DP1
0.66
1.48
13.1
3.7
6.3
2.5
9.3
Exi
stin
g 18
" C
MP
2DP2
1.39
3.22
13.1
3.7
6.3
5.2
20.1
Exi
stin
g 24
" C
MP
3DP6
0.86
3.41
14.3
3.6
6.0
3.1
20.6
Exi
stin
g 30
" C
MP
4DP8
0.47
1.63
13.6
3.7
6.2
1.7
10.0
Exi
stin
g 21
" C
MP
5DP2A
2.19
5.45
16.0
3.4
5.8
7.5
31.3
Pro
pose
d 36
" R
CP
* In
tens
ity
equa
tion
s as
sum
e a
min
imum
trav
el ti
me
of 5
min
utes
.C
alcu
late
d by
:D
P -
D
esig
n P
oint
Dat
e:E
X -
E
xist
ing
Des
ign
Poi
ntC
heck
ed b
y:IN
T-
Inte
rcep
ted
Flow
fro
m D
esig
n P
oint
VA
S
CM
N F
B-
Flow
By
from
Des
ign
Poi
nt7/
17/2
017
MS
CIV
IL, I
NC
Lot 4
8 H
igh
For
est R
anch
(P
ropo
sed)
700
487/
18/2
017
HYDRAULIC CALCULATIONS
GRADING AND EROSION CONTROL PLAN
EXISTING DRAINAGE MAP
PROPOSED DRAINAGE MAP
