HomeMy WebLinkAboutNOKOMIS SUBDIVISION - PRELIMINARY - 8-94 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORT+ AREA"8 (off drowlna) -
AREA "6
AREA I
3 A
BRISTLECONE) DR.
AREA we
CONIFER ST.
N
SCALE: 1°= 8001
s.7 AREA ��..•_i .
iAc-Ft: �s 7•�D H -�
Ac F �.. J n _20 ��p(0\
I AREA I A**.I
I 38 uo
216 217 _1 •6.4
�Ac-Ft
i
�I 213
IAc-IF
ILLOX
Northerly
Release Point
01------ f w
w AREA "2 AREA "OA —'
a- — 130 Z
o_
cn CONIFER ST. 105 220
I 101
-� 7�...
9.5
233 Ac-Ft 0 Ac-Ft
20 �.
214 AREA 120
} g AREA "OB
N
GP
�... 14.2..E o k4'
Ac-Ft �P
Y\ Southerly Release Point
205� DRY CREEK
NE DR.
NOTES: 1) SHAPE a SURFACE AREA OF PONDS APPROXIMATE ONLY.
2) POND NUMBERS ARE SAME AS BASIN NUMBERS.
LEGEND
BASIN . BOUNDARY
---- STORM SEWER OR CULVERTS
123 OPEN CHANNEL W/CONVEYANCE
CODE USED IN TABLE I.
C DETENTION PONDS
Ac-Ft
G11g1011] I
Release '
Point 1
IIIIIIIMI
P
TITLE EVERGREEN PARK FIGURE
4[
°°1`=o'ti, r FINAL DRAINAGE PATTERN 2
No Text
FEBRUARY1994
Manning's Equation for the Theoretical Capacity
of Non-Symetrical Triangular Section
0.200 = Side Slope 1 0.060 = Manning's (n)
0.200 = Side Slope 2 I This Section
0.200 = Side Slope 1
0.200 = Side Slope 2
0.01 = Channel Slope TYPICAL 2-in deep 1 0.004 = Channel Slope
0.060 = Manning's (n
� 1 This Section
TYPICAL 2-in deep
Flow Depth
Intercept Area 1 Intercept
Area 2
Total Discharge
Intercept
Area 1
Intercept
Area 2
arc
tal Discharge
[This
ft/ft
ft from CL s /ft ft from CL
s /ft
This Section cfs
ft from CL
s /ft
ft from Cl
s /ft
Section
0.50
2.501 0.631 2.50
0.63
1.21
2.50
0.63
2.50
0.631
0.77
0.601
3.00 ! 0.901 3.00
0.90
1.97
3.00
0.901
3.00
0.901
1.25
0.701
3.501 1.23 3.501
1.231
2.97
3.50
1.231
3.50
1.231
1.88
0.801
4.001 1.60 4.00
1.60
4.25
4.00
1.60'
4.00
1 .601
2.69
0.901
4.501 2.03
4.50
2.03
5.81
>`:
4.50
2.03I
4.50
2.031
3.68
00
5.00 j 2.50
5.00
2.50
7.70
5.00
2.50
5.00
2.50
4.87
101
5.501 3.03
5.50
3.03
9.93
_ `
5.50
3.031
5.50
3.03
6.28
M1.20
6.001 3.60
6.00
3.60
12.52
6.00
3.60
6.00
3.60
7.92
30
6.501 4.221
6.50
4.22
15.50
€#'
6.50
4.221
6.501
4.221
9.8040
7.001 4.90'
7.00
4.90
18.89
7.00
4.90
7.00
4.90
11.94
- All 12' easements are 12' for draipnge pans
ND + �SDU-r H t aCK .mot PVb Na,�� N z � N ��cK► I" �r�NS
ZIT C A`�'= W�pS CASE
_ r /
`7 �.� tC Li
� J
ST�;✓1%fi 5�-DAL,
v
r 4
r
1=I.UWI.I r- i/17(I+
1 I
/A[, �"H
i
—��YA1zn 5L�
DATA CONSTANTS
Type / Location NAKOMIS CT.
/ RESIDENTIAL
FLOWLINE CROSS
WIDTH (ft) SLOPE (ft)
F STREET
SLOPE (ft)
YARD
SLOPE (ft)
WALK
WIDTH (ft)
DEPTH @
CURB F.L.,
CURB
HEIGHT (ft
CROWN REDUCT'N
ELEV. FACTOR
36.001 0.02001
0.00401
0.0201
5.00
0.861 0.501
100.001 0.80
CALCULATED CONSTANTS
WETTED
PERIMETER
WEIGHT'D
MANNINGS1
I TOP
WIDTH
AREA
OF FLOW
97.011 0.02581
96.001
41.98
CALCULATED HYDRAULICS
THEO. ALLOW
CAPACITY cfs CAPACITY
WATER
ELEV.
VELOCITY
s
87.511 70.011
100.50
0.72
No Text
DRAINAGE CRITERIh MANUAL
RUNOFF
L' e �e.. • 5% =2 v = 1. S ?s
I•°7o
:'l�jy1�11�0 w�\S SL)31�IvISID
50
30
E- 20
z
w
U
cc
°
10
z
W
a
0
5
W
CC
3
O
U
2
w
I—
Q
/
-
/
--
3
Z-
3
4"
0
-
o° �
e
—
— hoc• J� ''? _
P
v tl =0 3P rP
C
_y 40
3
J
-
-
—_--
-
4
AV O
O
it/
W
QP
2 .3 .5 1. 1 2' 3 5 10 20
VELOCITY IN FEET PER SECOND
FIGURE 3-2. ESTIMATE OF AVERAGE FLOW VELOCITY FOR
1 USE WITH . THE RATIONAL FORMULA.
*MOST FREQUENTLY OCCURRING `UNDEVELOPED"
LAND SURFACES IN THE DENVER REGION.
REFERENCE: "Urban Hydrology For Small Watersheds" Technlcal
Release No. 55, USDA, SCS Jan. 1975.
5 -1-84
URBAN DRAINAGE d FLOOD CONTROL DISTRICT
STEWART&ASSOCIATES 10 S. MEL9 3D1RF , 4ORT COLLINS, CO 80521
82
Consulting Engineers and Surveyors
CP '� CnA� �� ►
By: �- Date: Z-%- la Client: ��>R�t, r�'• Sheet No. of
Project: A,1LOu-t\C \ CL)�.��utS«
Subject: I, -� AS r 6'� 1 \F'` 1�•
I-�I��lh�
�Z-
1 L(�►-�ti
vt1�C�iY
q-5 (, s��
►Fps 1.5 ��s
8
Z,6zk
�t,-70;(,s-�
I,�� I's
2.Iej
S�(2-t)/54o�.5)
101 1.5
D
0.93
50'(Z- ,')/PA
1.0/ pA
DEVELOPED RUNOFF COMPUTATIONS FROM RATIONAL METHOD
Q=CxCfxIxA
SUBBASIN T.O.C. (100yr
D. Pnt.
Sloe
C * Cf
Len th
OverLTc
Vel.Chan
Tc Chan.
Tc Total
COMMENTS
%
feet
min.
ft/sec.
min.
min.
A
2.00
0.75
55.00
3.9
Tc 100
0.501
1 485.00
1.50
5.391
9.2
LNGST.OVERL.+CHANNEL
0.60 = Runoff C
1.00 = Cf 2,10
1.25 =Cf 100
D. Pnt.
Area C * Cf
acres
I (2yr.)
in/hr
I (10yr.)
in/hr
I (100yr.)
in/hr)
Basin Q
(cfs)cfs
Comb. Q
COMMENTS
A
1.281 0.601
2.701
2.07
2.11
2 yr. runoff
0.60
3.00
2.30
2:3
10 r. runoff
0.751
7.00
6.72
6.7
La
100 yr. runoff
0.60 = C 1.00 =Cf 2,10 1.25 =Cf 100
SUBBASIN T.O.C. (100yr)
D. Pnt. Sloe
C * Cf
Length OverL To
Vel.Chan
I Tc Chan.
Tc Total
COMMENTS
y,
feet min.
fUsec.
min.
min.
B 2.00
0.75
55.001 3.9
1
Tc 100
0.50
670.001
1.501
7.41
11.3
LNGST.OVERI +CHANNEL
0.60 = Runoff C 1.00 = Cf 2,10 1.25 =Cf 100
D. Pnt.
Area
acres
C * Cf I (2yr.)
in/hr
I (10yr.)
in/hr
I (100yr.)
in/hr
Basin Q
cfs
Comb. Q
cfs
COMMENTS
B
2.64
0.601 2.40
3.80
3.8
2 r. runoff
0.601
4.20
6.65
6.7
10 r. runoff
0.75
6.90
13.66
13.7
100 r. runoff
0.60 = C 1.00=Cf(2,10) 1.25 =Cf 100
B
SUBBASIN T.O.C. 1001fr
D. Pnt.
Slope C * Cf Length
9, feet
OverL Tc
min.
Vel.Chan Tc an.
ft/sec. min.
Tc Total
min.
COMMENTS
C
2.00 0.751 50.001
3.7
1
1 Tc 100
1 1.501 1 540.001
2.501 3.6
7.31
LNGST. OVERL.+CHANNEL
0.60 = Runoff C 1.00 = Cf 2.10 1.25 =Cf 100
D. Pnt. Area C * Cf I (2yr.)
acres in/hr
I (10yr.)
in/hr
I (100yr.) Basin Q
in/hr)(cfs)
Comb. Q
(cfs
COMMENTS
C 2.181 0.601 2.80
3.661
3.7
2 r. runoff
1 0.601
5.001
6.541
6.5
10 yr. runoff
1 0.75 i
7.001 11.451
11.4
100 r. runoff
0.60 = C 1.00=Cf(2,10) 1.25=Cf(100) IC
6.10 = Area(ac) this page
DATE: FEBRUARY 1994
DEVELOPED RUNOFF COMPUTATIONS FOR 2/10/100 YR. STORMS
NAKOMIS SYBDIVISION
FOR: U.S.A.G. CAPITAL AND LEASING
BY: Stewart & Associates
GENERAL NOTES: Velocity in a Channel per FIGURE 3-2
If C x Cf > = 1 then C x Cf = 1 (constants listed below)
For design of the developed site runoff quantities Tc(100) was the basis for design
BANAKOMRO.wk3
HISTORIC RUNOFF COMPUTATIONS FROM RATIONAL METHOD
Q=CXCfXIXA
SUBBASIN T.O.C. 100 r
D. Pnt.
Slope
% '
C * Cf
Length
feet
Overt Tc
min.
Vel.Chan
ft/sec.
Tc Chan.
min.
Tc Total
min.
COMMENTS
1
1 1.001
0.25
360.00
30.2
Tc 100
1.001
0.00
1.50
0.0
30.2
LNGST.OVERL.+CHANNEL
0.20 = Runoff C
1.00 = Cf 2.10 1.25 =Cf 100
D. Pnt. Area
acres
C * Cf I (2yr.) 1 (10yr.)
in/hr in/hr
1 (100yr.)
in/h
Basin Q
cfs
Comb. Q
cfs
COMMENTS
1 3.521
0.201 1.481
1.0411
1.011
2 yr. runoff
0.201 2.60
1.83
t.8
10 r. runoff
0.251
4.16
3.66
3.7
100 yr. runoff
0.20 = C 1.00 =Cf 2,10 1.25 =Cf 100
1
SUBBASIN T.O.C. 100 r
D. Pnt. Slope C * Cf
%
Length
feet
Overt Tc Vel.Chan
min. f /sec.
Tc Chan.
min.
Tc Total
min.
COMMENTS
2 1 1.001 0.251
360.001
30.21
1
Tc 100
1 1.001
1 0.001
1 0,501
0.00
30.2
LNGST. OVERL. +CHANNEL
0.20 = Runoff C 1.00 = Cf 2.10 1.25 =Cf 100
D. Pnt.
Area
acres
C * Cf
I (2yr.)
in/hr
I (10yr.)
in/hr
I (100yr.) Basin Q
in/hr cfs
Comb. Q
cfs
COMMENTS
2
3.511
0.201
1.48
1! 1.04JJ
1.701
2 yr. runoff
0.201
2.601
1 1.83
10 r. runoff
0.251
4.16 3.65
LEA
100 r. runoff
0.20 = C 1.00 =Cf 2,10 1.25 =Cf 100
7.03 = Project Area (ac)
2-YEAR HISTORIC 2.08
PRELIMINARY HYDROLOGIC SUMMARY
NAKOMIS SUBDIVISION
TOTAL DEVELOPED RUNOFF
10.81
2 yr. runoff
17.8
10 r. runoff
36.4
100 r. runoff
NORTH BACKLOT PAN
2.11
2 yr. runoff
2.31
10 yr. runoff
6.71
100 yr. runoff
7.03 = Total project area(ac) Basins A
NAKOMIS COURT PAN
4.01
2 yr. runoff
5.61
10 yr. runoff
13.61
100 yr. runoff
Basins A + 13(1/2)
NAKOMIS COURT STREET FLOW
1.91 2 yr. runoff
3.31 10 yr. runoff
6.81 100 yr. runoff
BasinsB(1/2) EAUH SIUE
HISTORIC FLOW
2.11
2 yr.. runoff
3.71
10 yr. runoff
7.31
100 yr. runoff
FOTAL SITE
SOUTH BACKLOT PAN
3.71
2 yr. runoff
6.51
10 yr. runoff
11.4
J 100 yr. runoff
Basin C
FLOW TO OUTFALL CHANNEL #223
1.31 2 yr. runoff
2.31 10 yr. runoff
4.61 100 yr. runoff
Basin D
Nokomis Subdivision
Page 2
The site has good ground cover on most of the site. There is some existing
landscaping on the site, which will be retained as much as possible. Nokomis
Court will be rough cut and the utilities constructed thereafter. The area
from the front of the proposed houses to the rear concrete pan will not be
disturbed until the house is constructed. Straw bale barriers and rock filters
will be placed at discharge points.
The storm water runoff calculations and the preliminary grading and
drainage plan are enclosed as a part of this report. If you have any questions
regarding this report, please call.
Sincerely,
Richard A. Rutherford, E. & L.S.
President
jrr
enclosures
STEWART&ASSOCIATES
Consulting Engineers and Surveyors
February 7, 1994
Mr. Basil Harridan
Storm Water Utility
City of Fort Collins
P.O. Box 580
Fort Collins, Colorado 80522
Dear Basil:
The following is the preliminary storm drainage report for Nokomis
Subdivision, Fort Collins, Colorado. The site contains 5.20 net acres and
5.48 gross acres, including the west half of Redwood Street. It is located
on the west side of Redwood Street approximately 300 feet north of Conifer
Street in the Northwest a of Section 1, Township 7 North, Range 69 West of
the 6th P.M.
The site is in the Evergreen Park Drainage Basin. It is bounded on the
east by Redwood Street, on the south by the New Beginnings facility that has
been recently closed, on the west by existing industrial uses in Evergreen
Park and on the north by the proposed Greenbriar Village. The site slopes
from west to east at approximately 0.4% grade.
It is proposed to subdivide the site into 21 single—family detached
residential lots. The site will be divided into four developed sub —basins.
The existing Evergreen Park Detention Pond 130, as shown on the Evergreen Park
Basin Major Storm Drainage Study proposed by Engineering Professionals, Inc.
and dated February 1981, is adjacent to this site at the northwest corner of
the proposed subdivision. Also, the outfall channel from Pond 130 is along
the west boundary of the subdivision. It is proposed to carry the runoff,
undetained, from Sub —Basins "A", "B" and "C" in the curb and gutter of Nokomis
Court and in concrete pans along the north and south boundary lines to Redwood
Street. The runoff would then flow southerly in the west gutter of Redwood
Street to an existing 5—foot curb inlet and existing area inlet at the northwest
corner of Redwood Street and Conifer Street. Existing storm drains then would
carry the runoff to existing Detention Pond 120.
1
Sub —Basin "D" is the rear yards of Lots 10 through 13 which drain west
to the existing Outfall Channel No. 223. Channel No. 223 flows south across
Conifer Street to existing Detention Pond No. 150.
James H. Stewart
and Associates, Inc.
103 S. Meldrum Street
P.O. Box 429
Ft. Collins, CO 80522
303/482-9331
Fax 303/482-9382
PRELIMINARY DRAINAGE REPORT
FOR
NOKOMIS SUBDIVISION
FEBRUARY 7, 1994
STEWART & ASSOCIATES, INC.
103 SOUTH MELDRUM STREET
FORT COLLINS, COLORADO 80521
303/482-9331