HomeMy WebLinkAboutHEARTHFIRE PUD, 2ND FILING - FINAL - 31-95E - SUBMITTAL DOCUMENTS - ROUND 2 - DRAINAGE REPORTTABLE 5
CIRCULAR PIPE FLAW CAPACITY
Full Flow (cubic feet per second)
Mannings "n"= 0.013
Dia. *Conv. % Slope (feet per 100 feet)
(in.) Factor 0.02 0.05 0.10 . 0.20 0.35 0.50 0.75 1.00 1.25 1.50 1.75 2.0 2.5 5.0 10.0 20.0
(c.f.s.)
3 0.884 0.012 0.020 0.028 0.040 0.052 0.062 0.077 0.088 0.099 0.11 0.12 0.12 0.14 0.20 0.28 0.40
4 1.903 0.027 0.043 0.060 0.085 0.113 0.135 0.165 0.190 0.213 0.23 0.25 0.27 0.30 0.43 0.60 0.85
5 3.451 0.049 0.077 0.109 0.154 0.204 0.244 0.299 0.345 0.386 0.42 0.46 0.49 0.56 0.77 1.09 1.54
6 5.611 0.079 0.125 0.177 0.251 0.332 0.397 0.486 0.561 0.627 0.69 0.74 0.79 0.89 1.25 1.77 2.51
8 12.084 0.171 0.270 0.382 0.540 0.715 0.854 1.047 1.208 1.351 1.48 1.60 1.71 1.91 2.70 3.82 5.40
10 21.91 0.31 0.49 0.69 0.98 1.30 1.55 1.90 2.19 2.45 2.68 2.90 3.10 3.46 4.90 6.93 9.80
12 35.63 0.50 0.80 1.13 1.59 2.11 2.52 3.09 3.56 3.98 4.36 4.71 5.04 5.63 7.97 11.27 15.93
15 64.60 0.91 1.44 2.04 2.89 3.82 4.57 5.59 6.46 7.22 7.91 8.55 9.14 10.21 14.44 20.43 28.89
18 105.04 1.49 2.35 3.32 4.70 6.21 7.43 9.10 10.50 11.74 12.87 13.90 14.86 16.61 23.49 33.22 46.98
21 158.45 2.24 3.54 5.01 .7.09 9.37 11.20 13.72 15.85 17.72 19.41 20.96 22.41 25.05 35.43 50.11 70.86
24 226.22 3.20 5.06 7.15 10.12 13.38 16.00 19.59 22.62 25.29 27.71 29.93 31.99 35.77 50.59 71.54 101.17
27 309.70 4.38 6.93 9.79 13.85 18.32 21.90 26.82 30.97 34.63 37.93 40.97 43.80 48.97 69.3 97.9 138.5
30 410.17 5.80 9.17 12.97 18.34 24.27 29.00 35.52 41.02 45.86 50.24 54.26 58.01 64.85 91.7 129.7 183.4
36 666.98 9.43 14.91 21.09 29.83 39.46 47.16 57.76 66.70 74.57 81.69 88.23 94.33 105.46 149.1 210.9 298.3
42 1006.1 14.23 22.50 31.82 44.99 59.5 71.1 87.1 100.6 112.5 123.2 133.1 142.3 159.1 225.0 318.2 449.9
48 1436.4 20.31 32.12 45.42 64.24 85.0 101.6 124.4 143.6 160.6 175.9 190.0 203.1 227.1 321.2 454.2 642.4
* Conveyance Factor = (1.486 x R2/3 x A) / n
1
8
7
5
I—
w
w
u .4
A
15
12
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10
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II
6
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Figure 5-2
NOMOGRPAH FOR CAPACITY
OF from Buu o
CUgreaNING Public IN SUMPS,
DEPRESSION DEPTH 2"
A
5-10 DESIGN CRITERIA
MAY 1484
Project No 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
E2
FROM SUBBASIN T 5B
PROJECT:
HEARTHFIRE PUD
LOCATION:
TOWN CENTER DRIVE _ SOUTH SIDE
AREA (A)=
0.77
ACRES
RUNOFF COEF.
(C)
Refer to sub -basin breakdown on pages
2-year
10-year
100-year
C =
0.74
0.74
0.92
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH =
50
FEET
SLOPE =
1.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti (min)=
11.90
11.90
11.24
TRAVEL TIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope
Flow Type
Velocity
Tt
ft
%
fps
min
450
0.50
GUTTER
1.50
5.00
TOTAL TRAVEL TIME (min) =
5.00
L = 500
L/180+10
12.78
<
16.24
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc (min)=
12.78
12.78
12.78
USE Tc =
13
13
13
INTENSITY (I) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
I =
1.98
3.39
6.92
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
Q =
1.12
1.92
4.90
QTOTAL =
4.72
8.10
16.69
FROM FILING 1
Conclude:
Page 14 of 21
APPENDIX V
Grading and Drainage and Erosion Control Plan (3 Sheets)
THE WATER SUPPLY AND STORAGE COMPANY
2319 EAST NiULBERRY PHONE (303) 482.3433
P.O. BOX 1584
FORT COLLINS, COLORADO 80522
July 8, 1997
To whom it may concern
Re: Hearthfire P.U.D., Second Filing; Ft. Collins, Colorado
This note is provided in order to indicate the intent of The Water Supply and Storage Company to agree to
accept developed undetained stormwater runoff from the Hearthfire P.U.D. project to Richards Lake in a
pattern similar to historic flows which entered Richards Lake.
Our understanding is that water quality will be addressed. We also understand that an approval block will
be provided on the final utility plans for Hearthflre Y.U.D., Second Filing which will be as follows:
Water Supply and Storage
UTILITY PLAN APPROVAL
The undersigned on behalf of THE WATER SUPPLY AND
STORAGE COMPANY, the owner of Richards Lake, does
hereby agree to accept all runoff from Hearthfire P.U.D. in a
pattern similar to historic flows which entered this irrigation
reservoir.
President Date
We also understand that the final plat will be provided with the follo•.ving:
IRRIGATION COMPANY APPROVAL
The undersigned on behalf of THE WATER SUPPLY AND
STORAGE COMPANY, the owner of Richards Lake, does
hereby agree to accept all runoff from Hearthfire P.U.D. in a
pattern similar to historic flows which entered this irrigation
reservoir.
President
Date
If yo•-, have any question or comtnents, please call us at (970) 482-3433.
Sincerely,
Tom oore, esident
The Water Supply and Storage Company
cc: Richards Lake Development Company
APPENDIX IV
Water Supply and Storage Letter accepting stormwater from
Hearthfire Second Filing
TABLE 4
CIRCULAR PIPE FLOW CAPACITY
Full Flow (cubic feet per second)
Mannings "n"= 0.012
Dia. *Cony. % Slope (feet per 100 feet)
(in.) Factor 0.02 0.05 0.10 0.20 0.35 0.50 0.75 1.00 1.25 1.50 1.75 2.0 2.5 5.0 10.0 20.0
(c.f.s.)
3 0.957 0.014 0.021 0.030 0.043 0.057 0.068 0.083 0.096 0.107 0.12 0.13 0.14 0.15 0.21 0.30 0.43
4 2.062 0.029 0.046 0.065 0.092 0.122 0.146 0.179 0.206 0.231 0.25 0.27 0.29 0.33 0.46 0.65 0.92
5 3.738 0.053 0.084 0.118 0.167 0.221 0.264 0.324 0.374 0.418 0.46 0.49 0.53 0.59 0.84 1.18 1.67
6 6.079 0.086 0.136 0.192 0.272 0.360 0.430 0.526 0.608 0.680 0.74 0.80 0.86 0.96 1.36 1.92 2.72
8 13.091 0.185 0.293 0.414 0.585 0.774 0.926 1.134 1.309 1.464 1.60 1.73 1.85 2.07 2.93 4.14 5.85
10 23.74 0.34 0.53 0.75 1.06 1.40 1.68 2.06 2.37 2.65 2.91 3.14 3.36 3.75 5.31 7.51 10.61
12 38.60 0.55 0.86 1.22 1.73. 2.28 2.73 3.34 3.86 4.32 4.73 5.11 5.46 6.10 8.63 12.21 17.26
15 69.98 0.99 1.56 2.21 3.13 4.14 4.95 6.06 7.00 7.82 8.57 9.26 9.90 11.06 15.65 22.13 31.30
18 113.80 1.61 2.54 3.60 5.09 6.73 8.05 9.86 11.38 12.72 13.94 15.05 16.09 17.99 25.45 35.99 50.89
21 171.65 2.43 3.84 5.43 7.68 10.16 12.14 14.87 17.17 19.19 21.02 22.71 24.28 27.14 38.38 54.28 76.77
24 245.08 3.47 5.48 7.75 10.96 14.50 17.33 21.22 24.51 27.40 30.02 32.42 34.66 38.75 54.80 77.50 109.60
27 335.51 4.74 7.50 10.61 15.00 19.85 23.72 29.06 33.55 37.51 41.09 44.38 47.45 53.05 75.0 106.1 150.0
30 444.35 6.28 9.94 14.05 19.87 26.29 31.42 38.48 44.44 49.68 54.42 58.78 62.84 70.26 99.4 140.5 198.7
36 722.57 10.22 16.16 22.85 32.31 42.75 51.09 62.58 72.26 80.79 88.50 95.59 102.19 114.25 161.6 228.5 323.1
42 1089.9 15.41 24.37 34.47 48.74 64.5 77..1 94.4 109.0 121.9 133.5 144.2 154.1 172.3 243.7 344.7 487.4
48 1556.1 22.01 34.80 49.21 69.59 92.1 110.0 134.8 155.6 174.0 190.6 205.9 220.1 246.0 348.0 492.1 695.9
x Conveyance Factor = (1.486 x R2/3 x A) / n
F-
tAl
z
X
w
> -0
O
F_
w
O
_.z.0
O
z
O
.a:0
0
d-
7.. 1
6
EXAMPLE
:5°
.4
.3 ..
1
.-2'
I
.I-
D I 2 3 4 5
FLOW INTO INLET PER SO. FT. OF OPEN AREA (CFS/FT2)
Figure 5-3
CAPACITY OF GRATED INLET IN SUMP
(From: Wright -McLaughlin Engineers, 1969)
MAY 1984 5-11 DESIGN CRITERIA
"5.3.5 Grates for Pipes
Where a clear and present danger exists such as a siphon, a drop in elevation adjacent to a
sidewalk or road, a long pipe with one or more manholes, or at pipes which are near play-
grounds, parks, and residential areas, a grate may be required. For most culverts through
embankments and crossing streets, grates will not be required.
When called for on the plans, grates shall meet the following requirements:
a. Grating shall be constructed of steel bars with a minimum diameter of 5/8". Reinforcing
bars shall not be used.
b. Welded connections shall be 1/4" minimum.
c. Spacing between bars shall normally be 6" unless site conditions are prohibitive.
d. All exposed steel shall be galvanized in accordance with AASHTO M 111.
e. Welded joints shall be galvanized with a rust preventive paint.
f. Grates shall be secured to the headwall or end section by removable devices. such as
bolts or hinges to allow maintenance access, prevent vandalism, and prohibit entrance by
children.
'5.4 Inlets
Storm inlets shall be installed where sump (low -spot) conditions exist or street runoff -carrying
capacities are exceeded.
The curb inlets shown in the Standard Details, pages D-7, 8, 12 & 13, shall be used in all City Streets.
If larger inlets are required, the Colorado Department of Highways Type R Curb Inlet,`Standard M-604-
12, shall be used. For drainageways other than streets (for example, parking lots, medians, sump
basins) an Area Inlet similar to the detail on page D-9 shall be used.
The outlet pipe of the storm inlet shall be sized on the basis of the theoretical capacity of the.inlet, with
a minimum diameter of 15 inches, or.12 inches if elliptical or arch pipe is used.
All curb openings shall be installed with the opening at least 2 inches below the flow line elevation. The
minimum transition length shall be 3'6" as shown on the standard details previously listed.
=: Because'of debris plugging, pavement overlaying, parked vehicles; and other factors which decrease
inlet capacity, the reduction factors`listed in Table 5-4 shall be utilized.
Table 5-4
INLET CAPACITY REDUCTION FACTORS
Percentage of
Drainage Condition Inlet Type Theoretical Capacity
Sump or Continuous Grade ........................................... CDOH Type R-Curb
Opening
5' 80%
10, 85%
15, 90%
Street — Sump.............................................................. 4' Curb Opening 80%
Street — Continuous Grade .......................................... 4' Curb Opening 80%
Parking Lots, Medians ................................................... Area Inlet 80%
The theoretical capacity of inlets in a low point or sump shall be determined from Figures 5-2 and 5-3.
The theoretical capacity of curb openings on a continuous grade shall be determined from Figures 5-4,
5-5 and 5-6.
The standard curb -opening is, illustrated by Figure 5-4 and is defined as having a gutter depression
apron W feet wide at the inlet opening which extends W feet upstream and downstream from the open-
ing, has a depression depth (a) equal to W/12 feet at the curb face, and a curb opening height (h) of at
least 0.5 feet. The graph as presented by Figure 5-5 is based on a depression apron width (W) equal to
2 feet and depression width (a) equal to 2 inches. The pavement cross-section is straight to the curb
MAY 1984 5-8 DESIGN CRITERIA
3.1.7 Time of Concentration
In order to use the Rainfall Intensity Duration Curve, the time of concentration must be
known. This can be determined either by the following equation or the "Overland Time of
Flow Curves" from the Urban Storm Drainage Criteria.Manual, included in this report (See
Figure 3-2).
Tc =1.87 (1.1 - CCJ 012
S r,J
WhereTc=Time.of Concentration, minutes
S = Slope of Basin, %
C = Rational Method Runoff Coefficient
D = Length of Basin, feet
C, = Frequency Adjustment Factor
Time of concentration calculations should reflect channel and storm sewer velocities as well
as overland flow times.
3.1.8 Adjustment for Infrequent Storms
The preceding variables are based on the initial storm, that is, the two to ten year storms. For
storms with higher intensities an adjustment of the runoff coefficient is required because of
the lessening amount of infiltration, depression retention, and other losses that have a
proportionally smaller effect on storm runoff.
These frequency adjustment factors are found in Table 3-4.
Table 3-4
RATIONAL METHOD FREQUENCY ADJUSTMENT FACTORS
Storm Return Period
(years)
3.2 Analysis Methodology
Frequency Factor
C,
2 to 10 1.00
11 to25 1.10
26 to 50 1.20
51 to 100 1.25
Note: The product of C times C, shall not exceed 1.00
The methods presented in this section will be instituted for use in the determination and/or verification
of runoff at specific design points in the drainage system. These methods are (1), the Rational Method
and (2) the Colorado Urban Hydrograph Procedure (CUHP). Other computer methods, such as
SWMM, STORM, and HEC-1 are allowable if results are not radically different than these two. Where
applicable, drainage systems proposed for construction should provide the minimum protection as
determined by the methodology so mentioned above.
3.2.1 Rational Method
For drainage basins of 200 acres or less, the runoff may be calculated by the Rational
Method, which is essentially the following equation:
Q = C,CIA
Where Q = Flow Quantity, cfs
A = Total Area of Basin, acres
C, = Storm Frequency Adjustment Factor (See Section 3.1.8)
C = Runoff Coefficient (See Section 3.1.6)
I = Rainfall Intensity, inches per hour (See Section 3.1.4)
3.2.2 Colorado Urban Hydrograph Procedure
For basins larger than 200 acres, the design storm runoff'should be analyzed by deriving
synthetic unit hydrographs. It is recommended that the .Colorado Urban Hydrograph
Procedure be used for such ana!ysis. This procedure is detail -ad in the Urban Storm Drainage
Criteria Manual, Volume 1, Section 4.
MAY 1984 3-5 DESIGN CRITERIA
R-M-P Mediuln Density Planned Residential District — designation for medium density
areas planned as a unit (PUD) to provide a variation in use and building placements
with a minimum lot area of 6,000 square feet.
R-L-M Low Density Multiple Family District —areas containing low density multiple family
units or any other use in the R-L District with a minimum lot area of 6,000 square feet
for one -family or two-family dwellings and•9,000 square feet for multiple -family
dwellings.
M-L Low Density Mobile Home District — designation for areas for mobile home parks
containing independent mobile homes not exceeding 6 units per acre.
M-M Medium Density Mobile Home District — designation for areas of mobile home
parks containing independent mobile homes not exceeding 12 units per acre.
B-G General Business District — district designation for downtown business areas,
including a variety of permitted uses, with minimum lot areas equal to 1/2 of the total
floor area of the building.
B-P Planned Business District — designates areas planned as unit developments to
provide business services while protecting the surrounding residential areas with
minumum lot areas the same as R-M.
H-B Highway Business District — designates an area of automobile -orientated busi-
nesses with a minimum lot area equal to 1/2 of the total floor area of the building.
B-L Limited Business District — designates areas for neighborhood convenience
centers, including a variety of community uses with minimum lot areas equal to two
times the total floor area of the building.
C Commercial District —designates areas of commercial, service and storage areas.
I-L Limited Industrial District — designates areas of light industrial uses with a minimum
area of lot equal to two times the total floor area of the building not to be less than
20,000 square feet.
I-P Industrial Park District —designates light industrial park areas containing controlled
industrial uses with minimum lot areas equal to two times the total floor area of the
building not to be less than 20,000 square feet.
-G ` General Industrial District — designates areas of major industrial development.
T Transition District — designates areas which are in a transitional stage with regard
to ultimate development.
For current and more explicit definitions of land uses and zoning classifications, refer to the
Code of the City of Fort Collins, Chapters 99 and 118.
Table 3-3
RATIONAL METHOD RUNOFF COEFFICIENTS FOR COMPOSITE ANALYSIS
Character of Surface Runoff Coefficient
Streets, Parking Lots, Drives:
Asphalt................................................................................................ 0.95
Concrete............................................................................................. 0.95
Gravel................................................................................................. 0.50
Roofs.......................................................................................................... 0.95
Lawns, Sandy Soil:
Flat<2%............................................................................................. 0.10
Average2 to 7%.....................:............................................................ 0.15
Steep>7%.......................................................................................... 0.20
Lawns, Heavy Soil:
0.2
Flat<2%.............................................................................................
Average2 to 7%.................................................................................. 0.25
Steep>7%......... :......................................................... ....................... 0.35
MAY 1984 3-4 DESIGN CRITERIA
3.1.6 Runoff Coefficients ,
The runoff coefficients to be used with the Rational Method referred to in Section 3.2
"Analysis Methodology" can be determined based on either zoning classifications or the
types of surfaces on the drainage area. Table 3-2 lists the runoff coefficients for the various
types of zoning along with the zoning definitions. Table 3-3 lists coefficients for the different
kinds of surfaces. Since the Land Development Guidance System for Fort Collins allows land
development to occur which may vary the zoning requirements and produce runoff coeffi-
cients different from those specified in Table 372, the runoff coefficients should not be based
solely on the zoning classifications.
The Composite Runoff Coefficient shall be calculated using the following formula:
C = (SC;A;)/A,
Im1
Where C = Composite Runoff Coefficient
C; = Runoff Coefficient for specific area A;
A; = Area of surface with runoff coefficient of C;
n = Number of different surfaces to be considered
A,=Total area over which C is applicable; the sum of all A;'s is equal to A,
Table 3-2
RATIONAL METHOD RUNOFF COEFFICIENTS FOR ZONING CLASSIFICATIONS
Description of Area or Zoning
Business: BP, BL........................................................................................
Business: BG, HB, C..................................................................................
Industrial: IL, IP............................................................................................
Industrial: IG................................................................................................
Residential:,RE,_RLP..................................................................................
Residential: RL, ML, RP.............................................................................
Residential: FILM, RMP...............................................................................
Residential: RM, MM........................................................................:.........
Residential: RH...........................................................................................
....Parks: Cemeteries......................................................................................
Playgrounds...............................................................................................
RailroadYard Areas...................................................................................
UnimprovedAreas......................................................................................
Coefficient
0.85
0.95
0.85
0.95
0.45
0.50
0.60
0.65
0.70
0.25
0.35
0.40
0.20
Zoning Definitions
R-E Estate Residential District — a low density residential area primarily in outlying
areas with a minimum lot area of 9,000 square feet.
R-L Low Density Residential District — low density residential areas located throughout
the City with a minimum lot area of 6,000 square feet.
R-M Medium Density Residential District — both low and medium density residential
areas with a minimum lot area of 6,000 square feet for one -family or two-family
dwellings and 9,000 square feet for a multiple family dwelling.
R-H High Density Residential District— high density residential areas with a minimum lot
area of 6,000 square feet for one -family or two-family dwellings, 9,000 square feet
for a multiple family dwelling, and 12,000 square feet for other specified uses.
R-P Planned Residential District — designation of areas planned as a unit (PUD) to pro-
vide a variation in use and building placements with a minimum lot area of 6,000
square feet.
R-L-P Low Density Planned Residential District — areas planned as a unit (PUD) to permit
variations in use, density and building placements, with a minumum lot area of 6,000
square feet.
MAY 1984
3-3 DESIGN CRITERIA
No Text
FORT COLLINS
RAINFALL
INTENSITY
CURVE DATA FOR CITY OF FORT
COLLINS
2
10
100
2
10
100
TIME
YEAR
YEAR
YEAR
TIME
YEAR
YEAR
YEAR
5.00
2.85
4.87
9.95
32.00
1.24
2.12
4.33
5.50
2.760
4.715
9.630
32.50
1.230
2.100
4.285
6.00
2.67
4.56
9.31
33.00
1.22
2.08
4.24
6.50
2.595
4.435
9.055
33.50
1.205
2.060
4.200
7.00
2.52
4.31
8.80
34.00
1.19
2.04
4.16
7.50
2.460
4.205
8.590
34.50
1.180
2.020
4.120
8.00
2.40
4.10
8.38
35.00
1.17
2.00
4.08
8.50
2.350
4.015
8.205
35.50
1.160
1.980
4.045
9.00
2.30
3.93
8.03
36.00
1.15
1.96
4.01
9.50
2.255
3.855
7.875
36.50
1.140
1.945
3.970
10.00
2.21
3.78
7.72
37.00
1.13
1.93
3.93
10.50
2.170
3.705
7.570
37.50
1.120
1.910
3.900
11.00
2.13,
3.63
7.42
38.00
1.11
1.89
3.87
11.50
2.090
3.565
7.290
38.50
1.100
1.875
.3.835
12.00
2.05
3.50
7.16
39.00
1.09
1.86
3.80
12.50
2.015
3.445
7.040
39.50
1.080
1.845
3.770
13.00
1.98
3.39
6.92
40.00
1.07
1.83
3.74
13.50
1.950
3.340
6.815
40.50
1.060
1.815
3.710
14.00
1.92
3.29
6.71
41.00
1.05
1.80
3.68
14.50
1.895
3.240
6.615
41.50
1.045
1.785
3.650
15.00
1.87
3.19
6.52
42.00
1.04
1.77
3.62
15.50
1.840
3.135
6.410
42.50
1.030
1.755
3.590
16.00
1.81
3.08
6.30
43.00
1.02
1.74
3.56
16.50
1.780
3.035
6.200
43.50
1.015
1.730
3.535
17.00
1.75
2.99
6.10
44.00
1.01
1.72
3.51
17.50
1.725
2.945
6.010
44.50
1.000
1.705
3.485
18.00
1.70
2.90
5.92
45.00
0.99
1.69
3.46
18.50
1.675
2.860
5.835
45.50
0.985
1.680
3.435
19.00
1.65
2.82
5.75
46.00
0.98
1.67
3.41
19.50
1.630
2.780
5.675
46.50
0.970
1.655
3.385
20.00
1.61
2.74
5.60
47.00
0.96
1.64
3.36
20.50
1.585
2.705
•-5.530
47.50
0.955
1.630
3.335
21.00
1.56
2.67
5.46
48.00
0.95.
1.62
3.31
21.50
1.545
2.640
5.390
48.50
0.945
1.610
3.290
22.00
1.53
2.61
5.32
49.00
0.94
1.60
3.27
22.50
1.510
2.580
5.260
49.50
0.930
1.590
3.250
23.00
1.49
2.55
5.20
50.00
0.92
1.58
3.23
23.50
1.475
2.520
5.145
50.50
0.915
1.570
3.205
24.00
1.46
2.49
5.09
51.00
0.91
1.56
3.18
24.50
1.445
2.465
5.035
51.50
0.905
1.550
3.160
25.00
1.43
2.44
4.98
52.00
0.90
1.54
3.14
25.50
1.415
2.415
4.925
52.50
0.895
1.530
3.120
26.00
1.40
2.39
4.87
53.00
0.89
1.52
3.10
26.50
1.385
2.365
4.825
53.50
0.885
1.510
3.085
27.00
1.37
2.34
4.78
54.00
0.88
1.50
3.07
27.50
1.355
2.315
4.735
54.50
0.875
1.490
3.050
28.00
1.34
2.29
4.69
55.00
0.87
1.48
3.03
28.50
1.330
2.270
4.645
55.50
0.865
1.475
3.010
29.00
1.32
2.25
4.60,
56.00
0.86
1.47
2.99
29.50
1.310
2.230
4.560
56.50
0.855
1.460
2.975
30.00
1.30
2.21
4.52
57.00
0.85
1.45
2.96
30.50
1.285
2.185
4.470
57.50
0.845
1.440
2.940
31.00
1.27
2.16
4.42
58.00
0.84
1.43
2.92
31.50
1.255
2.140
4.375
58.50
0.835
1.425
2.905
59.00
0.83
1.42
2.89
59.50
0.825
1.410
2.875
60.00
0.82
1.40
2.86
DRAINAGE CRITERIA MANUAL
RUNOFF
/.
5C
30
1- 20
z
CC
U
w
° 10
z
w
0-
0 5
w
Cn
oc 3
O
U 2
w
H
3
1
.5
r ,
,INN I I
I r
I
I■■ANN
■■�
Sol
oil
/��II�I,■■►I�
■�
�■■■��
IN
IN
son
FA
IMF
MEN
` D 1 2 3 5 10 20
VELOCITY IN FEET PER SECOND
FIGURE 3-2. ESTIMATE OF AVERAGE FLOW VELOCITY FOR
USE WITH THE RATIONAL FORMULA.
*MOST FREQUENTLY OCCURRING"UNDEVELOPED"
LAND SURFACES IN THE DENVER REGION.
REFERENCE: "Urban Hydrology For Small Watersheds" Technical
Release No. 55, USDA, SCS Jan. 1975.
5 -1-84
URBAN DRAINAGE & FLOOD CONTROL DISTRICT
APPENDIX III
Supporting exhibits figures, tables. etc.
Figure 3-1; City of Ft.. Collins Rainfall Intensity Duration Curve
Figure 3-2; Estimate of Average Flow Velocity for Use with the Rational Formula
Table 3-3; Rational Method Runoff Coefficients for Composite Analysis
Table 3-4; Rational Method Frequency Adjustment Factors
Figure 4-2; Reduction Factor for Allowable Gutter Capacity
Fig 5-2 Nomograph for Capacity of Curb Opening Inlets in Sumps
Fig 5-3; Capacity of Grated Inlet in Sump
Table 4 Circular Pipe Flow Capacity for Mannings 'n' = 0.012
Table 5 Circular Pipe Flow Capacity for Mannings 'n' = 0.013
F:\Clients\H-Clients\Hearthfue Inc\Hearthfire P.U.D. Second Filing\Civil\Documents\Erosion\Sequence.doc
CONSTRUCTION SEQUENCE
PROJECT: Hearthfire P.U.D. Second Filing STANDARD FORM C
SEQUENCE FOR 1999-2000 ONLY COMPLETED BY:MEO/Shear Engineering Corp.
Indicate by use of a bar line or symbols when erosion control measures will be installed. Major modifications to an
approved schedule may require submitting a new schedule for approval by the City Engineer.
Year 99 00
Month 0 N D J F M A M J
OVERLOT GRADING ***
WIND EROSION CONTROL
Soil Roughening ***
Perimeter Barrier
Additional Barriers
Vegetative Methods
Soil Sealant
Other
RAINFALL EROSION CONTROL
STRUCTURAL:
Sediment Trap/Basin
Inlet Filters
Straw Barriers
Silt Fence Barriers *** *** *** *** ***
Sand Bags
Bare Soil Preparation
Contour Furrows
Terracing
Asphalt/Concrete Paving *** *** ***
Other
VEGETATIVE:
Permanent Seed Planting
Mulching/Sealant
Temporary Seed Planting
Sod Installation *** *** *** ***
Nettings/MatsBlankets
Other
STRUCTURES: INSTALLED BY: OWNER
MAINTAINED BY: OWNER
VEGETATION/MULCHING CONTRACTOR: OWNER
DATE PREPARED: 05/20/99 DATE SUBMITTED: 05/25/99
APPROVED BY THE'CITY OF FORT COLLINS ON:
Page 1
May 25, 1999
Project No: 1552-02-97
Re: EROSION CONTROL SECURITY DEPOSIT REQUIREMENTS:
Hearthfire P.U.D. Second Filing
A.
An erosion control security deposit is required in accordance with City of Fort Collins
policy (Chapter 7, Section C: SECURITY; page 7.23 of the City of Fort Collins
Development Manual). In no instance shall the amount of the security be
less than $ 1,000.00
According to current City of Fort Collins policy, the erosion control security deposit
is figured based on the larger amount of 1.5 times the estimated cost of installing
the approved erosion control measures or 1.5 times the cost to re -vegetate the
anticipated area to be disturbed by construction activity.
The cost to install the proposed erosion control measures is
Refer to the cost estimate attached in Appendix I.
1.5 times the cost to install the erosion control measures is
Net disturbed area due to construction activity will be
Cost to revegetate the disturbed area =
1'.5 times the cost to re -vegetate the disturbed area is
CONCLUSION:
The erosion control security deposit amount required for
Hearthfire P.U.D. Second Filing
will be F $15,930.00
$8,900.00
$13,350.00
20 acres.
$ 10,620.00
$ 15,930.00
4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-031 1
May 25, 1999
Project No: 1552-02-97
Basil Hamdan
City of Fort Collins Stormwater Utility
P.O. Box 580
Ft. Collins, Colorado 80522
Re: Hearthfire P.U.D. Second Filing
Dear Basil,
Attached is the erosion control security deposit estimate for Hearthfire P.U.D.
Second
Filing.
ESTIMATE 1 Erosion Control
Cost/unit
Unit
Cost
4000 LF of silt fence @
$ 1.70
LF
$67800.00
9 Gravel Inlet filter @
$ 150.00
Each
$1,350.00
10 Haybale barriers @
$ 75.00
Each
$750.00
TOTAL ESTIMATED COST:
$8,900.00
x 1.5
$13,350.00
ESTIMATE 2 Revegetate disturbed area
20 acres @ $ 531.00 $ 10,620.00
$531.00 per acre for areas greater than 5 acres. x 1.5
TOTAL ESTIMATED COST: 1 $ 15,930.00
In no instance shall the amount of the security be less than $ 1,000.00. Therefore, the
total required erosion control security deposit for Hearthfire P.U.D. Second Filing
will be $151930.00
If you have any questions, please call me at 226-5334.
Sincerely,
Mark Oberschmidt
Shear Engineering Corporation
MEO / meo
cc: Hearthfire Inc.
City of Fort Collins Stormwater Utility - Erosion Control Department
4836 s. College, Suite 12 Ft. Collins, CO 80525 (970) 226.5334 FAX (970) 282-031 1
MAJOR PS SUB
AREA
A EFF
CALCULATIONS
BASIN % BASIN
acre
AREA
C
P
4
8.12
Roof
3.64 acres
1.00
0.90
Sod
2.42 acres
0.01
1.00
Asphalt
0.85 acres
0.01
1.00
Wetland
1.21 acres
0.00
0.00
CHECK
8.12
C =
0.4523
P =
0.3225
6.94 EFF
85.41%
5
2.71
Roof
1.12 acres
1.00
0.90
Sod
0.75 acres
0.01
1.00
Asphalt
0.84 acres
0.01
1.00
CHECK
2.71
C =
0.4192
P =
0.3835
2.27 EFF
83.93%
6
9.02
Roof
1.80 acres
1.00
0.90
Sod
7.22 acres
0.01
1.00
Asphalt
0.00 acres
0.01
1.00
CHECK
9.02
C =
0.2076
P =
0.4900
8.10 EFF
89.83%
7
10.47
Roof
2.09 acres
1.00
0.90
Sod
8.38 acres
0.01
1.00
Asphalt
0.00 acres
0.01
1.00
CHECK
10.47
C =
0.2076
P =
0.4900
9.40 EFF
89.83%
8
5.31
Roof
0.41 acres
1.00
0.90 ,
Sod
0.09 acres
0.01
1.00
Asphalt
0.73 acres
0.01
1.00
CHECK
1.23
C =
0.0788
P =
0.1120
5.26 EFF
99.12%
TAL AREA = 39.31 ACRES
35.14
u ✓ERALL EFFECTIVENESS = 89.39% >
Conclude: Erosion Control Plan is effective
Page 2 of 2
EFFECTIVENESS CALCULATIONS
Project Hearthfire P.U.D.
Second Filing
By: MARK OBERSCHMIDT
EROSION CONTROL
-FACTO;
METHOD
VALUE
Roughened Ground
1.00
Silt Fence
1.00
Haybales
1.00
Asphalt concrete
0.01
Sod
0.01
Gravel Inlet Filters
1
MAJOR PS SUB
AREA
BASIN % BASIN acre
= WEIGHTED AVG OF C X AREA
= (WEIGHTED AVG OF P X AREA) X P
FF=(1 -PXC)X 100
Project
DATE:
P-FACTO
VALUE
0.90
0.50
0.80
1.00
1.00
0.80
SOD
ASPHALT
CHECK
C=
P=
0.70 EFF
Roo
Sod
Asphalt
CHECK
C=
P=
0.78 EFF
Roo
Sod
Asphalt
CHECK
C=
P=
1.68 EFF
STANDARD FORM B
1552-01-97
5/24/99
basins 1-8
basins 1-5
basins 1-5
basins 1-5
basins 1-5
AREA
0.18 ACRES
0.33 ACRES
0.78
0.3527
0.3089
89.10%
0.30 acres
0.20 acres
0.40 acres
0.90
0.3400
0.3867
86.85%
0.82 acres
0.55 acres
0.63 acres
2.00
0.4159
0.3836
84.05%
C
1.0C
0.01
0.01
0.01
0.01
0.01
0.01
P
0.90
1.00
1.00
1.00
1.00
1.00
1.00
Page 1 of 2
RAINFALL PERFORMANCE STANDARD EVALUATION
PROJECT: Hearthfire P.U.D. Second Filing PROJECT 1552-02-97 STANDARD FORM A
By: MARK OBERSCHMIDT DATE: 05/20/99
DEVELOPED
SUBBASIN
EROMITEITY
ZONE
Asb
(ac)
Lsb
(ft)
(%)
(feet)
(%) (%)
1
Moderate
0.
0.78
2
Moderate
0.90
420.00
1.20
378
1.08
3
Moderate
2.00
990.00
1.90
1980
3.80
4
Moderate
8.12
1285.00
1.90
10434
15.43
5
Moderate
2.71
955.00
0.90
2588
2.44
6
Moderate
9.02
400.00
4.00
3608
36.08
7
Moderate
10.47
1500.00
2.00
15705
20.94
8
Moderate
5.31
200
4
1062
21.24
Totals
39.31
919.89
2.59
LINEAR INTERPOLATION
If slope exceeds 5.0 must insert performance standards manually
6 SLOPE
7
LENGTH 2.50 2.59
3.00
900 81.7 81.79
82.2
919.89 81.79
1000 81.7 81.81
82.3
CONCLUDE:
PERFORMANCE STANDARD =
81.79%
EROSION CONTROL PLAN OVERALL EFFECTIVENESS MUST EXCEED THIS
Page 1 of 1
APPENDIX II
Erosion Control Calculations
TABLE 4 STORMCEPTORS CAPACITIES*
MODEL
MAX
SEDIMENT
OIL
TOTAL
TREATMENT
CAPACITY
CAPACITY
HOLDING
FLOWRATE
CAPACITY
GPM* CFS
CF
GAL
GAL
900
285 0.6350
70
805
951
1200
285 0.6350
110
1125
1233
1800
285 0.6350
195
1760
1860
2400
475 1.0583
255
2345
2495
3600
475 1.0583
405
3660
3768
4800
800 1.7824
555
4975
5060
6000
800 1.7824
710
6150
6096
7200
1110 2.4731
860
7480
7415
* APPROXIMATE
* WITHOUT BY PASSING
1
GALLON = 0.13368
CF
1
MIN = 60.00 SEC
1
GPM = 0.0022
CPS
Table 6
Maximum Impervious Drainage Areas Guidelines
(ac)
Model
Type 1 Type 2
Type 3
Type TT
1 2
3
4
Sensitive Normal
Degraded
TSS removal
80% 70%
60%
50%
900
0.45 0.55
0.70
0.90
1200
0.70 0.85
1.05
1.45
1800
1.25 1.50
1.90
2.55
2400
1.65 2.00
2.50
3.35
3600
2.60 3.15
3.95
5.30
4800
3.60 4.30
5.40
7.25
6000
4.60 5.55
6.95
9.25
7200
5.55 6.70
8.40
11.25
TT = Treatment Train
Table 5
By -Pass Flow*
Head
Bypass
Over
Flow
Weir
in
cfs
1
0.35
2
1.05
3
2.10
4
3.15
5
6.00
6
9.18
7
12.71
8
16.94
9
23.30
10
30.71
11
38.84
12
47.66
13
56.84
14
66.38
Project No. 1552-02-97 Shear Engineering Corporation
By: MEO
WATER QUALITY CAPTURE VOLUME FOR STORMCEPTOR SYSTEM (R)
Area
Area Type = 1 Type
5/25/99
Stormceptor
% TSS Removal 80% 1 Sensitive
Type 1 2 Normal
3 Degraded
4 Treatment Train
Design
SUB
Imperv.
Treated
STORMCEPTOR
Point
BASIN
Area (I)
Area*
MODEL*
ac
ac
A
1
0.61
0.70
1200
B
2
0.70
0.70
1200
C1
3A
0.32
na
na
C2
3A & 3B
1.45
1.65
2400
D1
4A
0.16
na
na
D2
4B
0.05
na
na
D3
4C
4.49
na
na
See note 1
E1
5A
2400
Installed with Filing 1
E2
5B
900
Installed with Filing 1
Note
1 Install water quality device downstream in swale
* REFER TO TABLE 6 IN STORMCEPTOR MANUAL
TREATMENT TRAIN OPTION - 50% TSS REMOVAL
Page 1 of 2
Project No 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
CHANNEL CAPACITY -in Tract D
Project
HEARTHFIRE PUD 2ND FILING
Description
Swale from
Town Center
Drive to Pond I - profile D
CAPACITY OF TRIANGULAR OR
TRAPEZOIDAL CHANNEL
CHANNEL
CONFIGURATION:.
Triangular
Q100 (cfs) =
CHANNEL LINING:
GRASS
1.33*Q100 (cfs) _
Da
Db Dc
Sc
n W
I
(ft)
(ft) (ft)
ft/ft
(ft)
(ft)
12.00
12.00 3.00
.0.0133
0.0600 0.00
0.50
P-Lt =
12.369317 0.25
ft/ft
= Left Bank Slope
4.00
P-Rt =
12.369317 0.25
ft/ft
= Right Bank Slope
4.00
DEPTH
WIDTH AREA
PERIM
R.v3 Sc 1/2
Q
(ft.)
(ft) (s.f.)
(ft)
(A/P)
(cfs)
3.00
24.00 36.00
24.74
1.28 0.1153
132.04
2.50
20.00 25.00
20.62
1.14 0.1153
81.20
2.00
16.00 16.00
16.49
0.98 0.1153
44.79
1.50
12.00 9.00
12.37
0.81 0.1153
20.80
1.00
8.00 4.00
8.25
0.62 0.1153
7.05
0.50
4.00 1.00
4.12
0.39 0.1153
1.11
2.09
16.75 17.53
17.26
1.01 0.1153
50.59
FLOW DEPTH FOR THE DESIGN FLOW IS APPROXIMATELY
FREEBOARD IN CHANNEL =
CONCLUDE:
CHANNEL WILL BE ADEQUATE
38.04
50.59
I (H:V)
I (H:V)
V
(ft/sec)
3.67
3.25
2.80
2.31
1.76
1.11
2.89
2.09 FEET
0.91 FEET
Y.
Page 21 of 21
Project No 1552-02-97 Shear Engineering Corporation
By: MEO
CHANNEL CAPACITY -AT EAST END OF BUNTWING
Project
HEARTHFIRE PUD 2ND FILING
Description
BUNTWING COURT - overflow
CAPACITY OF TRIANGULAR OR TRAPEZOIDAL CHANNEL
CHANNEL CONFIGURATION: Triangular Q100 (cfs) _
CHANNEL LINING: GRASS 1.33*Q100 (cfs)
_
Da
Db Dc Sc n W
I
(ft)
(ft) (ft) ft/ft (ft)
(ft)
4.00
4.00 1.00 0.0220 0.0600 0.00
0.25
P-Lt =
4.1231056 0.25 ft/ft = Left Bank Slope
4.00
P-Rt =
4.1231056 0.25 ft/ft = Right Bank Slope
4.00
DEPTH
WIDTH
AREA
PERIM
R 2/3
Sc 1/2
(ft.)
(ft)
(s.f.)
(ft)
(A/P)
1.00
8.00
4.00
8.25
0.62
0.1483
0.75
6.00
2.25
6.18
0.51
0.1483
0.50
4.00
1.00
4.12
0.39
0.1483
0.25
2.00
0.25
2.06
0.24
0.1483
0.99
7.94
3.94
8.18
0.61
0.1483
FLOW DEPTH FOR THE
DESIGN FLOW IS APPROXIMATELY
FREEBOARD IN CHANNEL =
CONCLUDE:
CHANNEL WILL BE ADEQUATE
Q
(cfs)
9.07
4.21
1.43
0.22
8.89
6.69
8.89
1 (H:V)
1 (H: V)
V
(ft/sec)
2.27
1.87
1.43
0.90
2.26
0.99 FEET
0.01 FEET
5/24/99
Storm
Page 20 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99,,
By: MEO Storm
CHANNEL CAPACITY -AT SOUTH END OF PONDVIEW
Project
HEARTHFIRE PUD 2ND FILING
Description
PONDVIEW COURT - overflow
CAPACITY OF TRIANGULAR OR
TRAPEZOIDAL CHANNEL
CHANNEL
CONFIGURATION:
Triangular
Q100 (cfs) _
CHANNEL LINING:
GRASS
1.33*Q100 (cfs)
_
Da
Db Dc
Sc
n
W
I
(ft)
(ft) (ft)
ft/ft
(ft)
(ft)
4.00
4.00 1.00
0.0200
0.0600
0.00
0.25
P-Lt =
4.1231056 0.25
ft/ft
= Left Bank Slope
4.00
P-Rt =
4.1231056 0.25
ft/ft
= Right Bank Slope
4.00
DEPTH
WIDTH AREA
PERIM
R 2/3
Sc in
Q
(ft)
(ft) (s.f.)
(ft)
(A/P)
(cfs)
1.00
8.00 4.00
8.25
0.62
0.1414
8.65
0.75
6.00 2.25
6.18
0.51
0.1414
4.02
0.50
4.00 1.00
4.12
0.39
0.1414
1.36
0.25
2.00 0.25
2.06
0.24
0.1414
0.21
0.93
7.41 3.43
7.63
0.59
0.1414
7.04
FLOW DEPTH FOR THE DESIGN FLOW IS APPRO}QMATELY
FREEBOARD IN CHANNEL =
CONCLUDE:
CHANNEL WILL BE ADEQUATE
5.29
7.04
1 (H:V)
1 (H: V)
v
(ft/sec)
2.16
1.79
1.36
0.86
2.05
0.93 FEET
0.07 FEET
Page 19 of 21
Project No. 1552-02-9.7 Shear Engineering Corporation 5/24/99
By: MEO Storm
Storm Sewer at Design Point E1
INSTALL 10 FOOT TYPE R INLET
SUMP
FOR Q100
CAPACITY PER FOOT (cfs/ft)=
2.45 BASED ON
FLOW DEPTH OF
REDUCTION FACTOR =
85.00% ACTUAL
CAPACITY =
20.83 CFS
PIPE DIAM. =
2.00 FT. PIPE TYPE =
RCP MANNINGS
SLOPE =
0.0235 FT/FT
SLOPE =
0.005
CONVEYANCE FACTOR=
226.22 -REFER TO TABLE
4 ADS MANUAL
CAPACITY =
34.68 CFS
PIPE OVERSIZED FOR OVERFLOW FROM POND 2
INLET SIZED FROM FILING 1
Storm Sewer at Design Point E2
INSTALL 10 FOOT TYPE R INLET SUMP FOR 100
CAPACITY PER FOOT (cfs/ft)= 2.45 BASED ON FLOW DEPTH OF
REDUCTION FACTOR = 85.00% ACTUAL CAPACITY = 20.83 CFS
PIPE DIAM. = 2.00 FT. PIPE TYPE = ADS MANNINGS
SLOPE = 0.0235 FT/Fr SLOPE = 0.005
CONVEYANCE FACTOR= 245.08 R TO TABLE 4 ADS MANUAL
CAPACITY = 37.57 CFS
PIPE OVERSIZED FOR OVERFLOW FROM POND 2
INLET SIZED FROM FILING 1
Storm Sewer at Design Point E
PIPE DIAM. = 2.00 FT. PIPE TYPE = ADS
SLOPE = 0.0235 Fr/Fr SLOPE = 0.005
CONVEYANCE FACTOR= 245.08 R TO TABLE 4 ADS MANUAL
CAPACITY = 37.57 CFS
PIPE OVERSIZED FOR OVERFLOW FROM POND 2
SIZE PIPE FROM DP D1 FOR 100 YEAR STORM =
PIPE DIAM. = 1.50 FEET ADS
MANNINGS N = 0.012 CONVEYANCE FACTOR =
SLOPE = 0.010 Fr/FT CAPACITY =
STREET CAPACITY FROM BACK OF WALK TO BACK OF WALK =
FLOW DEPTH AT FLOWLINE UP TO BACK OF WALK =
113.8
11.38
86.99
0.57 FEET
Page 18 of 21
Project No. 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
Storm Sewer at Design Point D 1
Design for 100 YEAR STORM FROM FIGURE 5-5
Q Sx T S Dw n
1.23 0.02 7.5 0.005 0.11 0.016
10 FOOT INLET REQUIRED FOR 100% INTERCEPTION
INSTALL 20 FOOT INLET Qi/Q = 2
INLET CAPACITY = 2.46 REDUCTION FACTOR = 85.00%
ACTUAL CAPACITY = 2.09 CFS
PIPE MATL n SLOPE C CAPACITY
2.5 ADS 0.012 0.0120 444.35 48.68
PIPE AND INLET ARE OVERSIZED FOR UPSTREAM FLOWS
Storm Sewer at Design Point D2
Design for 100 YEAR STORM FROM FIGURE 5-5
Q Sx T S Dw n
7.67 0.02 15 0.005 0.26 0.016
22 FOOT INLET REQUIRED FOR 100% INTERCEPTION
INSTALL 20 FOOT INLET Qi/Q = 0.95
THEORETICAL INLET CAPACITY = 7.29 CFS
'1UCTION FACTOR = 90.00% ACTUAL CAPACITY = 6.56 CFS
Storm Sewer at Design Point D3
Design for 100 YEAR STORM FROM FIGURE 5-5
Q Sx T Dw n S
40.00 0.02 15 0.26 0.016 0.005
22 FOOT INLET REQUIRED FOR 100% INTERCEPTION
INSTALL 15 FOOT INLET Qi/Q = 0.95
THEORETICAL INLET CAPACITY = 38.00 CFS
REDUCTION FACTOR =90.00% ACTUAL CAPACITY = 34.20 CFS
Storm Sewer at Design Point El
SIZE PIPE FROM DP E1 TO POND FOR 100 YEAR FLOW
PIPE DIAM. = 2.50 FEET ADS
MANNINGS N = 0.012 CONVEYANCE FACTOR = 444.35
SLOPE = 0.0089 FT/FT CAPACITY = 41.92
STREET CAPACITY FROM BACK OF WALK TO BACK OF WALK = 27.50
FLOW DEPTH AT FLOWLINE UP TO BACK OF WALK= 0.57 FEET
0
Page 17 of 21
Project No. 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
Storm Sewer at Design Point
A Pondview Court
Design for 100
YEAR STORM - Q 100 =
5.29 efs
INSTALL 5 FOOT TYPE R INLET IN SUMP
CONDITION
CAPACITY PER FOOT (ds/ft)=
1.34 BASED ON FLOW DEPTH OF
REDUCTION FACTOR =
80.00% ACTUAL CAPACITY =
5.36 CFS
PIPE DIAM. =
1.50 FT. PIPE TYPE = ADS
SLOPE =
0.0600 FT/FT MANNINGS n =
0.012
CONVEYANCE FACTOR=
113.8 -REFER TO TABLE
4 ADS MANUAL
CAPACITY =
27.88 CFS
Storm Sewer at Design Point
B Buntwing Court
Design for 100
YEAR STORM - Q100 =
2.43 efs
INSTALL 5 FOOT TYPE R INLET IN SUMP
CONDITION
CAPACITY PER FOOT (efs/ft)=
1.34 BASED ON FLOW DEPTH OF
REDUCTION FACTOR =
80.00% ACTUAL CAPACITY =
5.36 CFS
PIPE DIAM. =
1.50 FT. PIPE TYPE = ADS
SLOPE =
0.0100 FT/FT MANNINGS n =
0.012
CONVEYANCE FACTOR=
113.8 -REFER TO TABLE
4 ADS MANUAL
CAPACITY =
11.38 CFS
Storm Sewer at Design Point C 1
Design for 100 YEAR STORM FROM FIGURE 5-5
Q Sx
T
S Dw
n
2.43 0.02
7.5
0.05 0.11
0.016
30 FOOT INLET REQUIRED
FOR 100% INTERCEPTION
INSTALL 20 FOOT INLET
Qi/Q =
0.85
INLET CAPACITY =
2.07
REDUCTION FACTOR =
95.00%
ACTUAL CAPACITY =
1.97
PIPE MATL
n
SLOPE C CAPACITY
1.5 ADS
0.012
0.0100 113.8
11.38
Storm Sewer at Design Point
C2
Design for
10
YEAR STORM FROM FIGURE 5-5
Q Sx
T
S Dw
n
9.35 0.02
13.5
0.05 0.23
0.016
60 FOOT INLET REQUIRED
FOR 100% INTERCEPTION
INSTALL 20 FOOT INLET
Qi/Q =
0.6
INLET CAPACITY =
5.61
REDUCTION FACTOR =
90.00%
ACTUAL CAPACITY =
5.05
CFS
PIPE MATL
n
SLOPE C CAPACITY
1.5 RCP
0.016
0.0100 105.04
10.50
0.57 FOOT
0.57 FOOT
Page 16 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
E
FROM SUBBASIN 5
PROJECT:
HEARTHFIRE PUD
LOCATION:
TOWN CENTER DRIVE - NORTH SIDE
AREA (A)=
2.71
ACRES
RUNOFF COEF.
(C)
2-year
10-year
100-year
C =
0.74
0.74
0.93
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH =
30
FEET
SLOPE =
2.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti(min)=
7.33
7.33
6.93
TRAVEL TIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope
Flow Type
Velocity
Tt
ft
%
fps
min
50
0.50
gutter
1.50
0.56
105
4
gutter
4.00
0.44
770
0.5
gutter
1.50
8.56
TOTAL TRAVEL TIME (min) =
9.55
L = 955
L/180+10
15.31
<
16.47
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc (min)=
15.31
15.31
15.31
USE Tc =
15.5
15.5
15.5
INTENSITY (I) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
I =
1.84
3.14
6.41
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
QINLET =
3.70
6.30
16.11
Conclude:
A
Page 15 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99-
By: MEO Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
EI
FROM SUBBASIN 5A
PROJECT:
HEARTHFIRE PUD
LOCATION:
TOWN CENTER DRIVE - NORTH SIDE
AREA (A)=
1.94 JACRES
RUNOFF COEF.
(C)
Refer to sub -basin breakdown on pages
2-year
10-year
100-year
C =
0.75
0.75
0.93
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH =
30
FEET
SLOPE =
2.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti(min)=
7.33
7.33
6.93
TRAVEL TIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope
Flow Type
Velocity
Tt
ft
%
fps
min
50
0.50
GUTTER
1.50
0.56
105
4.00
GUTTER
4.00
0.44
770
0.50
GUTTER
1.50
8.56
TOTAL TRAVEL TIME (min) =
9.55
L = 1 955
L/180+10
15.31
<
16.47
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc (min)=
15.31
15.31
15.31
USE Tc =
16
16
16
INTENSITY (I) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
I =
1.84
3.14
6.41
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
QINLET =
2.66
4.53
11.57
Conclude:
Page 13 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
D
FROM SUBBASIN 4
PROJECT:
HEARTHFIRE PUD
LOCATION:
TOWN CENTER
COURT
AREA (A)=
8.12
ACRES
RUNOFF.COEF.
(C)
Refer to sub -basin breakdown on pages
2-year
10-year
100-year
C =
0.61
0.61
0.77
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH =
250
FEET
SLOPE =
4.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti (min)=
16.84
16.84
15.91
TRAVEL TIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope
Flow Type
Velocity
Tt
ft
%
fps
min
150
4.00
swale
3.00
0.83
550
0.5
gutter
1.50
6.11
235
2.5
gutter
3.10
1.26
100
0.5
gutter
1.50
1.11
TOTAL TRAVEL TIME (min) =
9.32
L = 1 1285
L/180+10
17.14
<
25.22
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc (min)=
17.14
17.14
17.14
USE Tc =
17.0
17.0
17.0
INTENSITY (I) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
I =
1.75
2.99
6.10
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
Q =
8.73
.14.91
38.04
QDP-D 1=
0.29
0.49
1.23
Qintercept @ DP D 1
QDP-D2 =
0.43
0.73
6.56
Qintercept @ DP D2
QDP-D3 =
8.19
14.00
34.20
Qintercept @ DP D3
QPIPE =
8.91
15.22
41.98
SIZE PIPE
Qup =
0.00
0.00
4.30
Q from DP
C2
Qtotal =
8.73
14.91
42.34
Conclude:
Install Storm Sewer to handle
runoff
Page 12 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99.
By: MEO Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
D3
FROM SUBBASIN 4C
PROJECT:
HEARTHFIRE PUD
LOCATION:
WEST SIDE TOWN CENTER
COURT
AREA (A)=
6.88
ACRES
RUNOFF COEF.
(C)
2-year
10-year
100-year
C =
0.69
0,68
0.85
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TWE (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH =
250
FEET
SLOPE =
4.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti(min)=
16.84
16.84
15.91
TRAVEL TIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope
Flow Type
Velocity
Tt
ft
%
fps
min
150
4.00
swale
3.00
0.83
550
0.5
gutter
1.50
6.11
235
2.5
gutter
3.10
1.26
100
0.5
gutter
1.50
1.11
TOTAL TRAVEL TIME (min) =
9.32
L = 11285
L/180+10
17.14
<
25.22
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc(min)=
17.14
17.14
17.02
USE Tc =
17.0
17.0
17.0
INTENSITY (I) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
1 =
1.75
2.99
6.10
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
Q =
8.19
14.00
35.69
Direct Flow
QUP =
0.00
0.00
4.30
Upstream Flow
QTOTAL =
8.19
14.00
40.00
QINT =
8.19
14.00
34.20
Qintercept
QPASS =
0.00
0.00
5.80
bypass flow to DP
El
Conclude:
Install Storm Sewer to handle
runoff
f-
Page 11 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
D2
FROM SUBBASIN 4B
PROJECT:
HEARTHFIRE PUD
LOCATION:
WEST SIDE TOWN CENTER COURT
AREA (A)=
1.04
ACRES
RUNOFF COEF.
(C)
Refer to sub -basin breakdown on pages
2-year
10-year
100-year
C =
0.24
0.24
0.30
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH =
250
FEET
SLOPE =
4.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti (min)=
16.84
16.841
15.91
TRAVELTIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope
Flow Type
Velocity
Tt
ft
%
fps
min
150
4.00
swale
3.00
0.83
550
0.5
gutter
1.50
6.11
235
2.5
gutter
3.10
1.26
100
0.5
gutter
1.50
1.11
TOTAL TRAVEL TIME (min) =
9.32
L = I 1285
L/180+10
17.14
<
25.22
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year,
10-year
100-year
Tc (min)=
17.14
17.14
17.14
USE Tc =
17.0
17.0
17.0
INTENSITY (I) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
I =
1.75
2.99
6.10
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
QINLET =
0.43
0.73
1.87
QUP =
0.00
0.00
5.80
Flow from DP
D3
QTOTAL =
0.43
0.73
7.67
TOTAL FLOW TO INLET
QINT =
0.43
0.73
6.56
INTERCEPTION
QPASS =
0.00
0.00
1.11
Bypass flow to DP
E2
Conclude:
Install Storm Sewer to handle
runoff
Page 10 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24%99_
By: MEO Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
D1
FROM SUBBASIN 4A
PROJECT:
HEARTHFIRE PUD
AREA (A)=
0.20
ACRES
RUNOFF COEF.
(C)
Refer to sub -basin breakdown on pages
2-year
10-year
100-year
C =
0.81
0.81
1.00
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH =
250
FEET
SLOPE =
4.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti (min)=
16.84
16.84
15.91
TRAVEL TIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope
Flow Type
Velocity
Tt
ft
%
fps
min
150
4.00
swale
3.00
0.83
550
0.5
gutter
1.50
6.11
235
2.5
gutter
3.10
1.26
100
0.5
gutter
1.50
1.11
TOTAL TRAVEL TIME (min) =
9.32
L =
I 1285
L/180+10
17.14
<
25.22
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc (min)=
17.14
17.14
17.14
USE Tc =
17.0
17.0
17.0
INTENSITY (I) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
I =
1.75
2.99
6.10
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
Q =
0.29
0.49
1.23
QINT =
0.29
0.49
1.23
INTERCEPTED FLOW
QPASS =
0.00
0.00
0.00
Conclude:
Install Storm Sewer to handle
runoff
Page 9 of 21
Project No 1552-02-97 Shear Engineering Corporation
By: MEO
5/24/99
Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
C
FROM SUBBASIN 3
PROJECT:
HEARTHFIRE PUD SECOND FILING
AREA (A)=
2.00
ACRES
RUNOFF COEF.
(C)
Refer to sub -basin breakdown on pages
2-year
10-year
100-year
C =
0.74
0.74
0.93
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH =
40
FEET
SLOPE =
1.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti(min)=
10.64
10.64
10.05
TRAVEL TIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope
Flow Type
Velocity
Tt
It
%
fps
min
520
0.50
GUTTER
1.5 0
5.78
230
4.00
GUTTER
4.00
0.96
100
2.00
GUTTER
2.83
0.59
100
5.00
GUTTER
4.45
0.37
TOTAL TRAVEL TIME (min) =
7.70
L = I 990
L/180+10
15.50
<
17.75
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc (min)=
15.50
15.50
15.50
USE Tc =
15.5
15.5
15.5
INTENSITY (1) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
1 =
1.84
3.14
6.41
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
QTOTAL =
2.73
4.66
11.91
QDPD1 =
0.59
1.00
1.97
Q intercepted @ C1
QDPD2 =
2.15
3.66
5.05
Q intercepted @ C2
QINT =
2.73
4.66
7.02
Q intercepted
QPASS =
0.00
0.00
4.89
bypass to DP B and D3
Conclude:
Page 8 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99,.
By: MEO Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
C2
FROM SUBBASIN T 313
PROJECT:
HEARTHFIRE PUD SECOND FILING
AREA (A)=
1.616
ACRES
RUNOFF COEF.
(C)
Refer to sub -basin breakdown on pages
2-year
10-year
100-year
C =
0.72
0.72
0.90
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH
1 40
FEET
SLOPE =
1.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti(min)=
10.64
10.64
10.05
TRAVEL TIME (Tt)
=L/(60*V)
NB.
All velocites take from figure 3-2
Length
Slope
Flow Type
Velocity
Tt
ft
%
fps
min
520
0.50
GUTTER
1.50
5.78
230
4.00
GUTTER
4.00
0.96
100
2.00
GUTTER
2.83
0.59
100
5.00
GUTTER
4.45
0.37
TOTAL TRAVEL TIME (min) =
7.70
L = 990
L/180+10
15.50
<
17.75
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc (min)=
15.50
15.50
15.50
USE Tc =
15.5
15.5
15.5
INTENSITY (I) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2 YEAR
10 YEAR
100 YEAR
I =
1.84
3.14
6.41
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
QINLET =
2.15
3.66
9.35
QINT =
2.15
3.66
5.05
Q intercepted @ DP
C2
QPASS =
0.00
0.00
4.30
1 Bypass Flow tp DP
D3
Conclude:
Install Storm Sewer to handle
runoff
Page 7 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
Cl.
FROM SUBBASIN 7 3A
PROJECT:
HEARTHFIRE PUD SECOND FILING
LOCATION:
EAST SIDE TOWN CENTER COURT
AREA (A)=
0.38
ACRES
RUNOFF COEF.
(C)
Refer to sub -basin breakdown on pages
2-year
10-year
100-year
C =
0.84
0.84
1.00
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH =
40
FEET
SLOPE =
1.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti (min)=
10.64
10.64
10.05
TRAVEL TIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope
Flow Type
Velocity
Tt
It
%
fps
min
520
0.50
GUTTER
1.50
5.78
230
4.00
GUTTER
4.00
0.96
100
2.00
GUTTER
2.83
0.59
100
5.00
GUTTER
4.45
0.37
TOTAL TRAVEL TIME (min) =
7.70
L = 990
L/180+10
15.50
<
17.75
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc (min)=
15.56
15.50
15.50
USE Tc =
15.5
15.5
15.5
INTENSITY (1) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
I =
1.84
3.14
6.41
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
QINLET =
0.59
1.00
2.43
QINT =
0.59
1.00
1.97
Q intercepted
QPASS =
0.00
0.00
0.47
Bypass Flow to DP
B
Conclude:
Install Storm Sewer to handle
runoff
Page 6 of 21
Project No 1552-02-97 Shear Engineering Corporation
By: MEO
5/24/99
Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
B
FROM SUBBASIN 2
PROJECT:
HEARTHFIRE PUD SECOND FILING
LOCATION:
BUNTWING COURT
AREA (A)=
0.90
ACRES
RUNOFF COEF.
(C)
Refer to sub -basin breakdown on pages
2-year
to -year
100-year
C =
0.78
0.78
0.98
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*LA0.5)/SA0.33
LENGTH =
40
FEET
SLOPE =
1.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti (min)=
10.64
10.64
10.05
TRAVEL TIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope
Flow Type
Velocity
Tt
ft
%
fps
min
50
5.00
GUTTER
4.45
0.19
30
2.50
GUTTER
3.10
0.16
140
1.00
GUTTER
2.00
1.17
160
0.50
GUTTER
1.50
1,78
TOTAL TRAVEL TIME (min) =
3.29
L =
1 420
L/180+10
12.33
<
13.35
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc (min)=
12.33
12.33
12.33
USE Tc =
12.5
12.5
12.5
INTENSITY (1) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
I =
2.02
3.45
7.04
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
Q =
1.42
2.43
6.22
QUP =
0.00
0.00
0.47
jUpstream flow from DP
C1
QTOTAL =
1.42
2.43
6.69
QOVER =
0.00
0.00
1.33
OVERFLOW SWALE
Conclude:
Install Storm Sewer to handle
runoff
Page 5 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
DEVELOPED
FLOW TO CONCENTRATION POINT
A
FROM SUBBASIN 1
PROJECT:
HEARTHFIRE PUD SECOND FILING
LOCATION:
POND VIEW COURT
AREA (A)=
0.78
ACRES
RUNOFF COEF.
(C)
Refer to sub -basin breakdown on pages
2-year
10-year
100-year
C =
0.78
0.78
0.98
TIME OF CONCENTRATION (Tc)
OVERLAND TRAVEL TIME (Ti)
(1.87*(1.1-C*Cf)*L^0.5)/S^0.33
LENGTH =
40
FEET
SLOPE =
1.00
%
2-year
10-year
100-year
C =
0.20
0.20
0.25
Ti(min)=
10.64
10.64
10.05
TRAVEL TIME (Tt)
=L/(60*V)
NB.
ALL VELOCITIES
TAKEN
FROM FIGURE
3-2
Length
Slope .
Flow Type
Velocity
Tt .
ft
%
fps
min
480
1.00
GUTTER
2.00
4.00
?
?
9
0.00
0.00
?
?
?
0.00
0.00
TOTAL TRAVEL TIME (min) =
4.00
L =
520
L/180+10
12.89
<
14.05
CHOOSE LESSER
Tc =Ti+TOTAL TRAVEL TIME
2-year
10-year
100-year
Tc (min)=
12.89
12.89
12.89
USE Tc =
13
13
13
INTENSITY (I) (iph)
NB.
INTENSITIES TAKEN FROM FIGURE
3-1
2-year
10-year
100-year
I =
1.98
3.39
6.92
RUNOFF (Q= CIA) (cfs)
2-year
10-year
100-year
QTOTAL =
1.21
2.07
5.29
QINLET =
1.21
2.07
5.29
QOVER =
0.00
0.00
0.00
No overflow Swale required
Conclude:
Install Storm Sewer to handle runoff
Grade minimal overflow swale for safety
Page 4 of 21
Project No 1552-02-97
Shear Engineering Corporation
By:
MEO
Im
Total
Pervious
Pervious
Sub-
Area
Area
Basin
ac
ac
1
0.18
0.61
0.78
2
0.20
0.70
0.90
3
0.55
1.45
2.00
4
3.63
4.49
8.12
5
0.75
1.96
2.71
6
5.25
3.77
9.02
7
6.06
4.41
10.47
8
4.25
1.06
5.31
Minor
Basin
3A
0.06
0.32
0.38
3B
0.49
1.13
1.62
4A
0.04
0.16
0.20
4B
0.99
0.05
1.04
4C
2.48
4.41
6.88
5A
0.53
1.41
1.94
0.22
0.55
0.77
5/24/99
Storm
Page 3 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
SUBBASIN BREAKDOWN
PROJECT: HEARTHFIRE PUD 2ND FILING
OPEN SPACE TRACTS
TRACT
AREA
AREA
PLATTED AREA
SF
ACRES
HEARTHFIRE
39.31
ACRES
A
66265
1.52
OPEN SPACE
8.28.
ACRES
B
120913
2.78
C
22193
0.51
ASSUME SINGLE FAMILY
LOTS ON THE SITE
ARE
D
112866
2.59
60.00% IMPERVIOUS - ROOF AND DRIVES
E
38523
0.88
40.00% PERVIOUS -LAWN
360760
8.28
Planimeter Constant
I SQ INCH =
65
SCALE:
I INCH =
100
IM-
PERVIOUS
PERVIOUS
PLANI
OPEN
ROADS
ROOF/
LAWN
C2
C100
SUB- METER
SF
ACRES
SPACE
DRIVES
BASIN READING
0.20
0.95
0.95
0.20
ACRES
ACRES
ACRES
ACRES
1 222
34154
0.78
0.00
0.34
0.27
0.18
0.78
0.98
2 255.5
39308
0.90
0.00
0.40
0.30
0.20
0.78
0.98
3 565
86923
2.00
0.00
0.63
0.82
0.55
0.74
0.93
4 2299
353692
8.12
1.21
0.85
3.64
2.42
0.61
0.77
5 766
117846
2.71
0.00
0.84
1.12
0.75
0.74
0.93
6 2554
392923
9.02
3.30
0.00
3.77
1.95
0.51
0.64
7 2964
456000
10.47
3.78
0.03
4.38
2.28
0.52
0.64
8 1503
231231
5.31
0.00
0.00
1.06
4.25
0.35
0.44
SUBTOTAL
1712077
39.30
8.29
3.09
15.35
12.57
0.55
0.69
IM-
PERVIOUS
PERVIOUS
PLANI
OPEN
ROADS
ROOF/
LAWN
C2
C100
MINOR METER
SF
ACRES
SPACE
DRIVES
BASIN READING
0.20
0.95
0.95
0.20
ACRES
ACRES
ACRES
ACRES
3A 107.5
16538
0.38
0.00
0.24
0.08
0.06
0.84
1.00
3B 457.50
70385
1.62
0.00
0.39
0.74
0.49
0.72
0.90
4A 57
8769
0.20
0.00
0.11
0.05
0.04
0.81
1.00
4B 294
45231
1.04
0.99
0.05
0.00
0.00
0.24
0.30
4C 1949
299846
6.88
0.00
0.69
3.72
2.48
0.68
0.85
5A 548
84308
1.94
0.00
0.62
0.79
0.53
0.75
0.93
5B 218
33538
0.77
0.00
0.22
0.33
0.22
0.74
0.92
Page 2 of 21
Project No 1552-02-97 Shear Engineering Corporation 5/24/99
By: MEO Storm
FLOW SUMMARY FOR STORM SEWER DESIGN IN
HEARTHFIRE PUD SECOND FILING
DESIGN SUB AREA C2 C100 Tc2, 10 yr ' T000 yr I2 I100 Q2 Q100
POINT BASIN(S)
ac. min. min iph iph cis ci's
DEVELOPED FLOWS FOR STORM SEWER IN SUB -BASIN 1 TO POND 2
A I 11 0.78 1
0.78 1 0.98
13.001
13.00 1.
1.98 1
6.92
1 1.211
5.29
DEVELOPED FLOWS FOR STORM SEWER IN SUB -BASIN 2
B 121 0.90 1
0.78 1 0.98 1
12.50 1
12.501
2.02 1
7.04
1.42 1
6.22
DEVELOPED FLOWS FOR STORM SEWER IN SUB -BASIN 3 TO POND 2
Cl 13A
0.38 1
0.84
1.00
1 15.50 1
15.50
1 1.84 1
6.41
1 0.59
2.43
C2
3B
1.62
0.72
0.90
1 15.50 1
15.501
1.841
6.41
1 2.15
9.35
C 13
2.00
0.74
0.93
15.50
1 15.501
1.841
6.41
1 2.73
11.91
DEVELOPED
FLOWS FOR STORM SEWER IN SUB -BASIN 4 TO POND 2
D1
14A
0.20
0.81
1.00
17.00
17.00
1.75
6.10
0.29
1.23
D2
4B
1.04
0.24
'. 0.30
17.00
17.00
1.75
6.10
0.43
1.87
D3
4C
6.88
0.68
0.85
17.00
17.00
1.75
6.10
8.19
35.69
D
4
8.12
0.61
0.77
17.00
17.00
1.75
6.10
8.73
38.04
DEVELOPED
FLOWS FOR STORM SEWER IN SUB -BASIN 5 TO RICHARDS LAKE
E1
5A
1.94
0.75
1 0.93
15.50
15.50
1.84
6.41
2.66
11.57
F�
5B
0.77
0.74
J 0.92
1 13.00
13.00
1.98
6.92
1.12
4.90
L
5
2.71
0.74
1 0.93
1 15.50
15.50
1.84
6.41
3.70
16.11
DESIGN DESIGN PIPE DESIGN INLET OG CAPA- PIPE RCP/ SLOPE CAPA-
POINT STORM INLET Q SIZE CITY DIAM ADS CITY
year BOTH cfs ft SUMP cfs ft ft/ft cfs
PROFILE A PONDVIEW COURT
A
100
BOTH 1
5.291
5
SUMP 1
5.361
1.50 JADS
I
0.067
27.88
PROFILE B BUNTWING COURT
B
100
BOTH 1 6.69 1 5
SUMP 1
5.36 1
1.50 JADS
1
0.010
11.38
PROFILE C TOWN CENTER DRIVE @ TRACTS E & C
Cl
100INLET
1 2.43
1 201
OGI
1.97
C2
10
BOTH
1 9.35
1 201
OGI
5.05
1 1.50
JRCP
1 0.010
1 10.50
C
100
PIPE
1 0.00
1
1
1
1 1.50
JADS
1 0.0101
11.38
PROFILE D TOWN CENTER
DRIVE @ TRACT A & C
DI
100
INLET
1.23
20
OG
2.09
D2
100
INLET
7.67
20
OG
6.56
D2
100
PIPE
40.76
2.50
RCP
0.0089
38.70
D3
100
BOTH
40.00
15
OG
34.20
2.50
RCP
0.0089
38.70
D
100
PIPE
41.98
2.50
ADS
0.0089
41.92
PROFILE E TOWN CENTER DRIVE - FILING 1
Q100
INLET
11.57
10
SUMP
20.83
2.00
RCP
0.0235
34.68
100INLET
1 16.691
10
ISUMP
1 20.83
1 2.00
JADS
1 0.0235
1 37.57
Page 1 of 21
APPENDIX I
Drainage Calculations
Page 12
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
VIIL VARIANCE FROM CITY STANDARDS
A. VARIANCE FROM CITY OF FORT COLLINS REQUIREMENTS
1. There will be no requests for variances from City of Fort Collins
Stormwater Utility Standards.
IX. CONCLUSIONS
A. COMPLIANCE WITH STANDARDS
I. The grading and drainage design for Hearthfire P.U.D., Second Filing is in
compliance with the City of Fort Collins storm drainage design criteria.
2. The erosion control measures shown on the erosion control plan comply
with the City of Fort Collins standards and generally accepted erosion
control practices.
B. DRAINAGE CONCEPT
1. The proposed drainage design for Hearthfire P.U.D., Second Filing is
effective for' the control of storm runoff with a considerable reduction in
potential downstream effects.
X. REFERENCES
1. City of Fort Collins "Storm Drainage Design Criteria and Construction
Standards"; May, 1984, revised May, 1997
2. City of Fort Collins "Erosion Control Reference Manual"; January, 1991
3. Preliminary Drainage and Erosion Control Report for Hearthfire at
Richards Lake; Prepared by Merrick & Company; Project No. 15011782;
Dated July 10,1996
4. Urban Runoff Mitigation for Hearthfire PUD, TR Boss Environmental and
Biological Consulting; Dated November 1996
5. Wetland Mitigation Report for Hearthfire P.U.D.; TR Boss Environmental
and Biological Consulting; Dated November 1996
6. Final Drainage and Erosion Control Report for Hearthfire P.U.D. Filing 1;
Prepared by Shear Engineering Corporation; Dated September, 1997,
Project Number 1552-01-96
Page 11
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
2. Stormceptors are sized based on the impervious area and a Type 1 habitat
because of the wetlands. Table 6 in the Stormceptor Technical Manual
was used as a guide in the design.
Table 3 - Stormceptor Summary
Street
Stormceptor Model
Pondview
1200
Buntwing
1200
Town Center
2400
3. A grassed channel is provided with storm sewer profile D for water
quality.
4. Annual maintenance is recommended on the Stormceptor manholes. This
has been noted on the plans. A note to this effect is on sheet 23.
VH. EROSION CONTROL:
A. GENERAL CONCEPT
1. Erosion control measures are specified on the Drainage and Erosion
Control Plan.
2. Maintenance of erosion control devices will remain the responsibility of
the contractor and the owner until the project is complete.
B. SPECIFIC DETAILS
1. The following temporary measures are specified on the Drainage and
Erosion Control plan:
a. Silt fence along the downstream property lines.
b. Gravel inlet filters at all storm sewer inlets.
c. Haybale dikes within all swales.
2. The following permanent measures are specified on the Drainage and
. Erosion Control plan:
a. Buried riprap aprons, D50 = 12" , at all storm sewer outfalls
b. Minimum length of riprap apron is 10 feet
c. Minimum width of the riprap apron will be 5.0 feet for 18" pipe and
6.0 feet for pipe larger than 24" .
Page 10
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
B. SPECIFIcDETAILS -SWALES
1. Overflow swales are provided at the end of the Pondview and Buntwing
Courts (Sections A -A and B-B). The swales are designed to convey the
overflow generated by the 100-year storm at the inlets in case the inlets
are clogged. The design flow is 1.33 x the Q100.
2. A Swale will also be constructed in Tract D (Section D-D) to convey
stormwater from Town Center Drive to Pond 1.
Table 2 Grassed Swale Summary Table
Section
Capacity
cfs
Qdesign
cfs
Depth
ft
Top
Width
ft
Slope
ft/ft
A -A
8.65
7.04
1.00
8.00
0.0200
B-B
9.07
8.89
1.00
8.00
0.0220
D-D
132.04
50.59
3.00
24.00
0.0133
I
VI. WATER QUALITY
A. GENERAL CONCEPT
1. Water quality measures are specified in the Water Quality and Wetland
Mitigation Report prepared by Ted Boss, Ph.D. A copy of this report is on
file in the office of Stormwater Utility
2. Maintenance of water quality measures will be the responsibility of the
contractor and the owner until the project is complete. The Homeowners
Association will be responsible upon completion of the construction.
B. SPECIFIC DETAILS
1. Stormceptor ® manholes will be installed with the storm sewers that
outfall into the Pond 1. Stormceptors are located on the downstream side
of the last Type R inlet in the storm sewer profile. They are located in
close proximity to the inlet and the street so as to provided easier access
for maintenance crews.
Page 9
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
4. Storm sewer D located on Town Center Drive south of Buntwing Court
will consist of the following;
a. 1 - 15' Type R inlet in continuous grade condition on the west side of
Town Center Drive.
b. 30 " RCP pipe between inlets
c. 2 - 20' Type R inlets in continuous grade condition on the east and
west side of Town Center Drive.
d. 30 " RCP pipe between inlets.
e. 30 " HDPE pipe (ADS N-12 or approved equal) with FES.
f. Grassed swale
g. 30" RCP to pond
5. Storm sewer E, which was built with Filing 1, located on Town Center
Drive east of Golden Eagle Court consists of the following;
a. 2 - 10' Type R inlet in sump condition designed and constructed with
Filing 1
b. The overflow storm sewer from Pond 2 to Richards Lake designed and
constructed with Filing 1.
Table 1 Storm Sewer Sununary Table
Profile
Street
No. of
inlets
Type of
Pipe
On Grade
Sump
Q100
cfs
Qinlet
cfs
A
Pondview
1
ADS
Sump
5.29
5.36
B
Buntwing
1
ADS
Sump
6.22
5.36
C
Town Center
2
IRCP & ADS
On Grade
11.91
7.02
D
Town Center
3
1 RCP & ADS
On Grade
1 42.341
41.98
Page 8
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
V. Specific Details - Storm Sewer
1. Storm sewer A located at the low point on Pondview Court will consist of
the following;
a. 1 - 5' Type R inlet in sump condition
b. 1 — Stormceptor Manhole Model No. 1200
c. 18 " HDPE pipe (ADS N-12 or approved equal) with FES to pond.
d. 1 — storm sewer manhole
e. Overflow Swale
2. Storm sewer C located on Town Center Drive north of Buntwing Court
will consist of the following;
a. 1 - 20' Type R inlet in continuous grade condition on the west side of.:
Town Center Drive.
b. 18 " RCP pipe from inlet to inlet.
c. 1 - 20' Type R inlet in continuous grade condition on the east side of
Town Center Drive.
d. 1 — Stormceptor Manhole Model No. 2400
e. 18 " HDPE pipe (ADS N-12 or approved equal) with FES to the pond.
3. Storm sewer B located at the low point on Buntwing Court will consist of
the following;
a. 5' Type R inlet in sump condition
b. 1 — Stormceptor Manhole Model No. 1200
c. 18 " HDPE pipe (ADS N-12 or approved equal) with FES.
d. Overflow Swale
Page 7
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
D. HYDRAULIC CRITERIA
1. Storm sewer inlet design is based on the inlet curves provided in the City
of Fort Collins Drainage Criteria Manual. The entire storm sewer
infrastructure is designed using the 10-year storm. This exceeds the City
Requirement of the 2-year design storm.
2. Storm sewer design is based on Mannings Equation with Manning's
coefficients as suggested in the City of Fort Collins Drainage Criteria
Manual.
IV. DRAINAGE FACILITY DESIGN
A. GENERAL CONCEPT
1. The majority of the site (sub -basins 1-4) will be contributing stormwater
to the wetland / pond areas (Pond 2) via a combination of
a. overland flow
b. gutter flow
c. storm sewer flow
2. The grading of the site attempts to divert as much of the runoff into the
wetland areas as possible.
3. Sub -basins 5 & 7 will contribute stormwater directly to Richard Lake or
Douglas Road via the same methods of conveyance mentioned previously.
Sub -basin 8 contributes stormwater to pond 1.
4. Water quality is addressed in the design of the outfalls of the storm sewer
into Richards Lake. Refer to the Wetlands Mitigation Report prepared by
TR. Boss Associates. Water Quality details coincide with the
recommendations of the report.
5. Emergency overflow structures were designed and constructed with Filing
1 to pass any stormwater that exceeds the storage capacity of the wetland /
pond areas safely to Richards Lake.
6. Any swales that have slopes less than 1.0 percent will have 3' valley pans
installed at the flow line of the swale.
Page 6
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
III. DRAINAGE DESIGN CRITERIA
A. REGULATIONS
1. This final report and the Master Grading, Drainage and Erosion Control
Plans for Hearthfire P.U.D., Second Filing were prepared in accordance
with the requirements of the current City of Fort Collins Storm Drainage
Design Criteria and Erosion Control Criteria.
B. DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS
County Road 13 will be widened with this project and the proposed
grading along the west property line will have to match the proposed
design of the road.
2. The existing wetland areas retain much of the stormwater that flows to
them. Emergency overflow structures were necessary to convey the
stormwater, which exceeds the capacity of the wetlands out of the wetland
areas safely to Richards Lake. These were designed and constructed with
Hearthfire P.U.D., First Filing.
3. The design intent is to divert as much of the runoff as possible to Ponds 1 a`
and 2 for the purpose of water quality.
C. HYDROLOGIC CRITERIA
I. Runoff calculations at various design points are based on the "Rational"
method. The 2, 10, and 100-year storms have been analyzed. All runoff
calculations have been performed using the current rainfall IDF curves
dated March 16, 1999.
2. No detention is proposed with this subdivision because the existing
wetland areas will act as temporary retention ponds.
Page 5
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
4. Pond 1 is crossed by the proposed access road (Hearthfire Way) to the
First Filing from Douglas Road which was designed with Hearthfire
P.U.D., First Filing.
5. Pond 2 is the wetland area that is within the limits of Hearthfire P.U.D.,
First Filing.
6. The stormwater that is intercepted by the wetlands either percolates into
the soil or evaporates. An exception to this occurs when storm events
exceed the storage capacity of the low areas. The stormwater eventually
overflows into Richards Lake when this occurs.
7. Richards Lake is the ultimate destination of all runoff from the site
including any water that exceeds the storage capacity of the wetland /
pond areas.
C. HISTORIC CONDITIONS
1. The overall site which includes filing 1 and 2 can be divided into 6 historic
sub -basins designated A-F. These basins are undeveloped with a few
active oil wells located on them as well as some wetland areas. We are
utilizing the "C" factor for sandy soils with an average slope because of
the wetlands present for most of the basin. We have assumed a "C" factor
of 0.45 for Sub -basin F that consists of large estate lots in Cherrywood
Acres. The table below summarizes the sub -basins for the entire
Hearthfire property, their total area and the immediate destination of the
flow from them.
Sub -basin
Area
Flow Destination
acres
A
50.53
Pond 1
B
57.59
Pond 2
C
40.50
Richards Lake
D
10.64
Richards Lake via Richards
Lake PUD
E
13.75
Serramonte Highlands
F
12.16
Douglas Road and east
2. The total area of the sub -basins is 185.17 acres. Sub -basins A-E contribute
stormwater to Richards Lake. There are also an additional 91.8 acres on
the north side of Douglas Road that contributes runoff to pond 1.
Page 4
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
B. DESCRIPTION OF THE PROPERTY
1. Hearthfire P.U.D., Second Filing is a proposed residential subdivision in
the City of Fort Collins, Colorado. The overall subdivision consists of
approximately 146 single-family homes. There are a total of 57 lots
proposed with this filing.
2. Hearthfire P.U.D., Second Filing has a platted area of approximately 39.31
acres.
3. The site is currently vacant and is covered with native vegetation.
4. There are some existing oil wells on the site.
H. DRAINAGE BASINS AND SUB -BASINS
A. MAJOR BASIN DESCRIPTION
1. The site is located in the Dry Creek Basin as delineated on the City of Fort
Collins Stormwater Basin Map."
2. This portion of the Dry Creek Basin is partially developed with large
single family lots and medium sized ranches.
B. SUB -BASIN DESCRIPTION
1. The site topography is best described as rolling. There are several ridges
on the site, which create several sub -basins. The site generally slopes
from the northeast to the southwest at an average rate of 0.04 ft/ft (4.0 %).
2. The basin is defined by Douglas Road to the north, County Road 13 to the
west and Richards Lake to the south. The eastern property line of the
entire site is the eastern boundary of the basin.
3. There are two (2) existing wetlands / ponding areas east of the site which
intercept much of the runoff from the site and retain it. Grading proposed
in these areas with Hearthfire P.U.D., First Filing created permanent water
features. They are designated Pond 1 and Pond 2 on the Hearthfire P.U.D.
Final Drainage and Erosion Control Plan.
Page 3
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
INTRODUCTION
This report presents the pertinent data, methods, assumptions, references and calculations
used in analyzing and preparing the final drainage and erosion control design for the
proposed Hearthfire P.U.D. Second Filing site. All assumptions and basin delineations
are essentially the same as those developed with Hearthfire P.U.D. First Filing.
I. GENERAL LOCATION AND DESCRIPTION
A. PROPERTY LOCATION
1. Hearthfire P.U.D., Second Filing is located in the West one-half (1/2) of
Section 30, Township 8 North, Range 68 West of the 6th P.M., Larimer
County, Colorado.
2. More specifically, it is located on the south side of Douglas Road (County
Road 54), approximately 1.5 miles east of the intersection of Douglas
Road and State Highway 1.
3. The site is bounded on the west by County Road 13, on the north by
Douglas Road and Cherrywood Acres, on the east by Hearthfire P.U.D.,
First Filing and on the south by Richards Lake.
4. Richards Lake is located immediately south of Hearthfire P.U.D., Second
Filing. Storm runoff from the site has historically entered Richards Lake
and will continue to do so with the development of Hearthfire P.U.D.,
Second Filing.
5. Richard Lake is owned and operated by The Water Supply and Storage
Company.
6. The Water Supply and Storage Company has indicated that they will
accept undetained flows from Hearthfire P.U.D., Second Filing in a
manner similar to historic acceptance.
7. A statement has been provided with the Hearthfire P.U.D, Second Filing
Utility Plans and Final Plat indicating the reservoir company's acceptance
of undetained flows to Richards Lake.
8. The Water Supply and Storage Company has provided a letter indicating
their intent to accept undetained flows to Richards Lake. A signed copy of
this letter is attached to this report and is located in Appendix IV.
Page 2
Final Drainage and Erosion Control Report
Hearthfire P.U.D., Second Filing
TABLE OF CONTENTS
INTRODUCTION.................................................................................................................................. 3
I. GENERAL LOCATION AND DESCRIPTION:........................................................................... 3
A.
PROPERTY LOCATION.................................................................................................................... 3
B.
DESCRIPTION OF THE PROPERTY..................................................................................................... 4
H.
DRAINAGE BASINS AND SUB-BASINS..................................................................................... 4
A.
MAJOR BASIN DESCRIPTION........................................................................................................... 4
B.
SUB -BASIN DESCRIPTION............................................................................................................... 4
C.
HISTORIC CONDITIONS................................................................................................................... 5
M.
DRAINAGE DESIGN CRITERIA............................................................................................. 6
A.
REGULATIONS...............................................................................................................................
6
B.
DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS...............................................................
6
C.
HYDROLOGIC CRITERIA.................................................................................................................
6
D.
HYDRAULIC CRITERIA...................................................................................................................
7
IV. DRAINAGE FACILITY DESIGN............................................................................................. 7 .,,.
A. GENERAL CONCEPT.......................................................................................................................7
B. SPECIFICDETAILS-SWALES......................................................................................................... 10
VI. WATER QUALITY.................................................................................................................. 10
A. GENERAL CONCEPT..................................................................................................................... 10
B. SPECIFICDETAILS........................................................................................................................ 10
VII. EROSION CONTROL:
11
A.
GENERAL CONCEPT.....................................................................................................................
i I
B.
SPECIFIC DETAILS........................................................................................................................
I I
VIII.
VARIANCE FROM CITY STANDARDS.............................................................................
12
A.
VARIANCE FROM CITY OF FORT COLLINS REQUIREMENTS.............................................................
12
IX.
CONCLUSIONS.......................................................................................................................12
A.
COMPLIANCE WITH STANDARDS..................................................................................................
12
B.
DRAINAGE CONCEPT....................................................................................................................
12
X. REFERENCES
APPENDIX I — Drainage Calculations
APPENDIX II — Erosion Control Calculations
APPENDIX III — Charts and Figures
APPENDIX IV - Water Supply and Storage Letter
APPENDIX V - Stuffer Envelope
........ 12
May 25, 1999
Project No: 1552-02-97
Basil Harridan
City of Ft. Collins Storm Water Utility
P.O. Box 580
Ft. Collins, Colorado 80524
Re: Hearthfire P.U.D., Second Filing; Ft. Collins, Colorado
Dear Basil,
Enclosed please find the Final Drainage and Erosion Report and Plans for Hearthfire
P.U.D., Second Filing. The hydrology data and the hydraulic analysis presented in this
report complies with the requirements of the City of Fort Collins Storm Drainage Criteria
Manual; dated March, 1984, revised May, 1997 and the Erosion Control Reference
Manual.
We understand that the City has revised rainfall IDF curves. All runoff calculations have
been performed using the current rainfall IDF curves dated March 16, 1999
If you have any questions or comments, please call me at 226-5334.
Sincerely,
yk`
Mark Oberschmidt
Shear Engineering Corporation
MEO / meo
cc: Hearthfire, Inc.
Reviewed by
Brian W. Shear, P.E.
Shear Engineering Corporation
4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282.031 1
FINAL DRAINAGE AND EROSION CONTROL
REPORT
For
HEARTHFIRE P.U.D., SECOND FILING
Ft. Collins, Colorado
Prepared for:
Hearthfire, Inc.
C/o Gilligan Homes
11941 West 48th Avenue
Wheat Ridge, Colorado 80033
Prepared By:
SHEAR ENGINEERING CORPORATION PRINT DATE
Project No: 1552-02-97
Date: May, 1999 MAY 2 51999,
SHEAR ENP,INEERlNG CDRP
4836 S: College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-0311