HomeMy WebLinkAboutDrainage MemorandumDrainage Memorandum
To: Chris Bendon
From: Jesse K. Swann, PE
Date: October 01, 2025
Re: Drainage Memo -Sweetwater Ranch Guest Cabin 4
Encl: Appendix
Sopris Engineering LLC (SE) has prepared this drainage memo in support of the Grading & Building permit application for a cabin
located in Garfield County. The proposed residence is situated on Tract G-8, which encompasses 165.2 acres within the SB35
Subdivision Exemption Plat. The SB35 Subdivision is a recently recorded subdivision consisting of several parcels, each exceeding
35 acres, all located within an active 2,659+1- acre working ranch under common ownership.
This memo includes a description of the existing site conditions, proposed improvements, and the general approach to stormwater
routing, considering the open expansiveness of the ranch and surrounding area.
Section A -Existing Site Overview:
The existing site is located approximately 1 mile west of Sweetwater Road. Access to this portion of the ranch is currently available
via a private gravel road that extends from Sweetwater Road through the ranch. The SB35 Subdivision is a working ranch that will
continue operations involving cattle raising and hay production. Improvements to the existing gravel access road, including an
extension to serve the proposed residence and other structures have been reviewed and approved by the U.S. Army Corps of
Engineers, Garfield County, and Eagle County. Additionally, design of the road has been coordinated and approved by the Gypsum
Fire District.
The surrounding topography consists of relatively hilly terrain, with slopes ranging from 10% to 20%, generally trending east to
northeast. Vegetation in the area includes pinyon pine, Gambel oak, and sagebrush, along with cultivated pastures featuring several '
lateral irrigation ditches used for flood irrigation.
Sweetwater Creek, located approximately 0.9 miles east of the proposed residence site (as the crow flies), is the ultimate receiving
waterbody. Although Sweetwater Creek is not included in FEMA Flood Insurance Rate Maps, floodplain studies conducted in
anticipation of future bridge crossings indicate that the 100-year floodway and floodplain remain confined near the ordinary high-
water mark, all of which are well below the proposed residential site. Surface runoff from the building site follows existing drainage
patterns, which are conveyed over and through irrigated pastures and areas of partially vegetated ground cover typical of high -
elevation, and environments. Figure 1 is provided to illustrate the proposed location of the residence and surrounding area.
Figure 1-Aerial Image of Site
502 Main Street, Suite A3, Carbondale, CO 81623 970-704-0311
pg. 1
Section B-Project Overview:
The proposed project involves the construction of a cabin, attached carport, gravel driveway, covered patio, utility improvements,
and landscaping enhancements. The landscaping will be designed to complement the surrounding vegetation and will be irrigated
using water supplied from Beaver Reservoir, located approximately 0.5 miles west of the site on the SB35 Subdivision property.
Grading activities will be carefully planned to minimize disturbance to existing topography and vegetation. Cut and fill operations
will be conducted in accordance with best management practices (BMPs) to ensure erosion control and sediment containment
during construction. Temporary sediment control measures, such as sediment control logs and silt fences, will be implemented
around the site to prevent sediment migration from the development area and to protect existing waterways and drainage courses.
Additionally, erosion and sediment control BMPs will be maintained throughout construction, with inspections conducted in
compliance with the State issued Storm Water Management Plan permit, regularly to ensure their effectiveness. Final grading will
be completed to promote positive drainage away from the residence, reducing the potential for ponding or surface runoff issues.
After construction is complete, disturbed areas will be stabilized through landscaping and revegetation to prevent erosion and
establish permanent ground cover.
Section C-Post Development Drainage Analysis:
To properly size the proposed storm water mitigation infrastructure for the project, the post development site was divided into
several drainage basins. The post development drainage basins are described in detail below. It should be noted that roof basins
were identified and evaluated, however they will not direct runoff towards the proposed stormwater mitigation infrastructure.
Design Point 1— This design point corresponds with the outfall of Swale 1, with a single basin being tributary to DP1.
Basin 1: A basin that is created from a natural ridge and the previously permitted Activity Barn Access Road, terrain is
relatively and with grades under 20%
Design Point 2 — This design point is located along the eastern side of the site at the outfall of Swale #2, with a single basin
being tributary to DP2:
Basin 2: A very small and basin that is tributary to Swale #2.
Section D-H drolo is Methods and Assumptions:
Post -development drainage areas were analyzed using the Rational Method (Equation 1) since the cumulative total of tributary
areas are less than 90 acres.
Equation 1: Q = C * I * A
Q = Runoff Flow Rate (cfs); C = Runoff Coefficient
I = Rainfall Intensity (in/hr); A= Area of Basin (acres)
The runoff coefficient (C) represents .the ratio of runoff volume to rainfall volume during a storm event. Its determination is influenced
by several factors, including soil type, the percentage of impervious area within the watershed, and the frequency of storm events.
Each drainage basin was analyzed to quantify its percentage of impervious area.
The effective impervious area for each basin was then used to derive a weighted runoff coefficient. A spreadsheet tool developed
by the Mile High Flood District (MHFD) of Denver, CO was used to calculate site -specific runoff coefficients. This tool allows for the
calculation of site -specific C values based on a Type C hydrologic soil classification and associated impervious areas.
The MHFD spreadsheet, which is included in Appendix, also computes the time of concentration (Tc), the time it takes for runoff to
travel from the furthest point upstream in a basin to the designated design point, accounting for both overland and channelized
flow. A minimum time of concentration of 5 minutes was adopted for the smaller developed basins. The Tc values were then used
to estimate the corresponding 100-year rainfall intensities based on NOAA rainfall data for the surrounding area.
502 Main Street, Suite A3, Carbondale, CO 81623 970-704-0311
pg. 2
Table 1, provided below, presents the areas, C values, Tc, intensities and resultant 100-year peak runoff rates for the post -
development drainage basins.
Table 1 - Post Development Peak 100-Year Runoff Rates
Table 1: Post Development Drainage Basin: Rational Method Summary
Drainage Basin ID
Area
(ac)
Percent
Impervious
Runoff
Coefficient, C
Selected
Tc (min)
I
Rainfall
Intensity (inlhr)
Peak Flow,
Q (cfs)
100-yr
I 100-yr
100-yr
POST DEVELOPMENT OFFSITE BASINS
BASIN 1
1.916
13.19%
1 0.54
1 15.5
1 4.16
4.30
BASIN 2
1 0.160
2.0°/a
0.49
10
5.18
0.40
ROOF BASINS
ROOF-1
0.02
100.0%
0.89
5
7.08
0.14
ROOF-2
0.03
100.0%
0.89
5
7.08
0.19
ROOF-3
0.03
100.0%
0,89
5
7.01
0.21
ROOF -FLAT
0.03
100.0%
0.89
5
7.08
0.17
Section E-Hydraulic Methods and Assumptions:
The 100-year post -development peak runoff rates summarized in Table 1 were used to size the proposed stormwater conveyance
system, which includes one culvert and two swales.
Culvert Sizing: Hydraflow Express Extension was used to size the single culvert located beneath the driveway. Hydraflow Express
employs an energy -based Standard Step methodology to estimate culvert flow capacities. For maintenance and efficiency
purposes, a minimum culvert diameter of 18 inches was adopted. The proposed culvert will be constructed from ADS N-12 smooth
interior pipe, utilizing a Manning's Roughness Coefficient of 0.013, which reflects the flow roughness characteristics of the pipe
material. A description of the proposed culvert is summarized below.
Culvert 1: Is an 18" ADS N-12 pipe located under the driveway at the eastern side of the cabin and is designed to convey water
from Swale 1 and Basin 1 under the driveway and direct flow to the north side of the cabin.
To accurately estimate culvert capacity, flow increments of 0.25 cubic feet per second (cfs) were evaluated iteratively until just prior
to overtopping. These flow estimates were cross-referenced with the total 100-year peak runoff rate tributary to the culvert. Table
2 summarizes the tributary peak runoff rates, the corresponding culvert capacities based on size, depth, material, and slope.
Supporting calculations are provided in the Appendix.
Table 2-Culvert Sizing Summary
CULVERT DESIGN SUMMARY
Culvert ID
Tributary Drainage
Q� (cfs)
Size (in)
Capacity
I
Basin ID
(ems)
CULVERT 1
BASIN 1 4.30
18 12.75
Swale Sizing: Swales are proposed within the development to convey surface runoff around the proposed development. Manning's
Equation (Equation 2) was used to estimate the dimensions of the proposed drainage swales, employing the 100-year peak runoff
rates associated with tributary basins in conjunction with the minimum and maximum proposed longitudinal slope for each swale.
Roughness coefficients were determined based on the intended treatment for each swale. Swale dimensions were inputted into
Hydraflow software accounting for maximum and minimum longitudinal slopes. A brief description of the proposed swales is
provided below:
502. Main Street, Suite A3, Carbondale,. CO 81623 970-704-0311
pg. 3
Equation 2: _ 1.49 (a 3 A * S2
q — n \PW
Q = Channel Capacity (cfs)
n = manning's runoff coefficient (native: n = 0.027)
A = Area of flow (sf)
Pw = Wetted perimeter of channel (ft)
S = Channel longitudinal slope (ft/ft)
Swale 1: Located along the southwest side of the cabin, this swale was designed to intercept and convey both historic and
post development flows generated from Basin 1 and directs runoff towards Culvert 1.
Swale 2: Located along the southeast side of the cabin, this swale was designed to intercept and convey both
historic and post development flows generated from Basin 2 and directs runoff around the east side of the
proposed cabin.
A summary of the resultant swale analysis as performed with Hydraflow is provided in Table 3.
Table 3-Swale Sizing Summary
SWALE DESIGN SUMMARY
SWALE ID
CONTRIBUTING
BASINS
SLOPE
(%)
Q100
(CFS)
n
VELOCITY
(ft/sec)
FLOW DEPTH
(ft)
MIN. DEPTH
PROVIDED (ft)
FULL FLOW
CAPACITY (CFS)
SWALE #1 BASIN 1
S.8%
4.30
0.030
4.74
0.55
1.0
21.8
SWALE #2 BASIN 2
2.00%
0.40
0.030
1.70
0.28
1.0
12.8
Section F-Erosion Control:
Erosion control measures are essential to mitigate drainage issues and prevent soil erosion during construction activities. While
the responsibility for implementing these measures lies with the Contractor under the State -issued Stormwater Management Plan,
the following erosion control practices are minimum recommendations to help reduce sediment transport and soil degradation.
• Pre -Construction Measures: Before any clearing, grubbing, lot grading, or construction work begins, the contractor
shall establish temporary sediment control logs and/or embedded silt fencing around the anticipated limits of
disturbance.
• Culvert Protection: Hay bales and sediment control logs should be placed at the inlets and outlets of all culverts to
prevent sediment from contaminating the culverts prior to the establishment of vegetation.
• Topsoil Management: Topsoil designated for removal and reuse shall be stockpiled with sediment control logs or silt
fencing around their perimeters. If stockpiles are to remain for more than 15 days, temporary seed should be applied
to prevent erosion and weed growth.
• Ditch Control: Install sediment control logs within the flowline of ditches at appropriate intervals to reduce flow
velocities and capture sediment.
• Site Inspections: The site must be inspected and recorded in accordance with the State issued SWMP. Silt deposits
behind silt fencing and sediment control logs should be regularly cleared to ensure the effectiveness of the erosion
control system. These inspections and maintenance activities must be documented in a logbook readily available for
inspection.
502 Main Street, Suite A3, Carbondale, CO 81623 970-704-0311
pg. 4
Vegetation Establishment: Seed and mulch shall be applied over disturbed cut and fill slopes, with watering as
necessary, to establish permanent vegetative ground cover.
Slope Stabilization: Erosion control blankets and/or hydromulching shall be applied to all cut and fill slopes that exceed
a 3:1 slope ratio.
Vehicle Tracking Control: Vehicle tracking control devises shall be installed at the entrance to Sweetwater Road to
prevent tracking onto the public roadways.
Temporary erosion control measures installed during construction should remain in place and be maintained until new vegetation
is established at a 70% growth level. Once soil stabilization is satisfactory, temporary erosion control structures may be removed.
Given the dynamic nature of construction sites, the final location and selection of BMPs shall be at the contractor's discretion. All
necessary permits must be acquired prior to the commencement of construction, and the criteria outlined in these permits must be
adhered to until the associated permits are closed.
Section G-Conclusions:
The drainage analysis indicates that the proposed improvements will not adversely impact the subject property or surrounding
areas. Offsite and onsite runoff will be appropriately managed via the proposed drainage system which has been sized to safely
convey the 100-year storm event associated with the proposed development. Lastly, erosion control BMPs will be enforced prior
throughout construction in compliance with State issued SWMP permit.
For further questions or additional information, please feel free to contact me.
Prepared by: Jesse K. Swann, PE
❑�p,� 0. 11 �k
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42787
A� 10-01 2025
S�QNAL
Encl:
Exhibit A: Post Development Drainage Basin Delineation Map
NOAA Rainfall Depth Chart
Hydraflow Culvert Hydraulic Calcs
Hydraflow Swale Capacity Calcs
Mile High Flood District Spreadsheet
502 Main Street, Suite A3, Carbondale, CO 81623 970-704-0311
pg. 5
100-YEAR PEAK RUNOFF RATES
y^
HYDROLOO IC FEATURE SUMMARY TABLE
rin'a'w tiw Fx
Precipitation Frequency Data Server
https:Hhdse.nws.noaa.gov/pfds/pfds_printpage.html?lat=39.7551 &Ion=...
NOAA Atlas 14, Volume 8, Version 2
Location name: Gypsum, Colorado, USA*
Latitude: 39.7551°, Longitude:-107.1036'
Elevation: 6997 ft40
-
source: ESRI Maps
source: USGS
POINT PRECIPITATION FREQUENCY ESTIMATES
Sanja Perica, Deborah Martin, Sandra Pavlovic, Ishani Roy, Michael St, Laurent, Carl Trypaluk, Dale
Unruh, Michael Yekta, Geoffery Bonnin
NOAA, National Weather Service, Silver Spring, Maryland
PF tabular I PF_grap- ical I Maas_&_ e i l
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches/hour)1
Average
recurrence interval (years)
potation
25 50
100 200 500 1000
1
2
�5 � 10
5-min
1.62
{1.30 2.05)
2.10
.68.2T88
2.96
2�38 .79y
3.77
(2,99 a•8�
4.97
(3.84-6.82)
5.99
�q_48 8.33��
7.08
5.09_10
8.27
(5.66-1i.3)
9.96
58.53-16.3)
11.3
{?.18-17.6)
10-min
Q.954 9.51
1.2451 9fi
1( 73-2.77]
(2Y19," 53
�2.81-4 99)
(3- 8.6.1D +
3. 3 744 ,
{4. ".99}
(4,78301.2
5.5-312.9]
15-min
0 661 22
s1. 0 9559
1.417�Z6}
(7: 8-2.88)
28-4.06]J
�2. 6 as96j�
3. 3 6?O5
3.37--7231
7�0.5]
0.800
30-min
mA880772j
0.8( 9B•1.43y�
(1,1140.791...1
t1.37-242)
{1.5&2.88
t( T33.4a}
1.8[ 8_4•�
(2.b9�89}
(2.25.5.53)
60-min
0.384
0.809-0.488
0.486
{0.39D-0.818)[(0.523-0.63By,
0. 555
0.797
D.6331.D2)
0.9 66
0.759-1.34
1.15
0.855-158.
1.31
(0.935-1,85)
1.47
..[1.00-2.18
1.69
1.10-2.57)
1.86
(1.18-2,68
1,
37
2-hr
0.198 0 2�I
(0.2312-06
{p.302-0.473y�
�,358 0 569
{0.42 -0727]
{0.4fi9 0 B46)
(0.50 -0 982].
{4.5378313}
0.5831 33
[D.fi1966
1
3-hr
0.178
_
- --_._....
398r0 897
0.145.0.223
a.1072-0.285
D 20i5-0.334
D 251-D 384
0.291-0 497
0.322 0 574]
{0.346-❑ fi64
{0.367-0.783
{0A22-0.998
1
0. 13
6-hr
(0.094-0442
0.106-0.161)I
(0.108-0 i9$
(0.145-012
165-0278]
T. 82-0.318)
(0.I -0 366)'
(D-2-0,420)
(0.2N-OA !
(0237-0.548)-
0.081j
0.098
0.113
I
0151
1
0187
0.212
02310.071
(0.067-0.100]
8#
.0134.
.
4
.15
0.10-6
32-0.262
.0.143-0.308)05.2-0.3
42)�12-hr
24-hrJ
0.04 -0061)
i
t0.fl51-D075j
.w
D05-0067-008
4
10.037--0053) ,
l(0.074-094)
9 1
S
0148
!�
98-R.216 1
0.050
0.057
r 0. 664
1 0.071
0.081
0.089
0.027
0.030
0. 337 11
0.042
(0 022-0.032}t
'!]} 025-0.037)
(0_fl31-0.0d4)
D.035-0.051),
�O- 40-0.064�
(0.045-0074)
(0-048-0.085)
l'0.051-0.096)
0.056-0.115)
(0.060-0.129
_2-day
0.020
023F
0.028
0.032
0.038
0.043
0.048
0.053
0.061
0.066
3-day
0.017-0.024
{R.R19 R.027)
[0.023 0.033)�
{D.D27-0.038],
{0.031-0.048J,
(0.034 R.055j+
[0-036-0. LMI
[0.038.0.D73},
D.D42 0.085j.
[0.[i45 O.D95
4-day
l
l
0019
0J
0023 I02026
0.031
5-Q_
0.07)
0.035
0.039
9
0.043
1-0058t
0.049
(0.034D
036.0A70.0148
.
.019-0027
D390016
[D.D27mo.044
.00.053
0
0
7-day
-0 015){
001-0018)
1..p
iB10.8-0.0
.28[:19.0032)
(0.020.0.!P
0,022-0D43)j
(0.023
-0.047}(0.00-0
.012
026
10-day
{0:048-0.011]
o.ODB 0 812
'00�0-0 014
{0.0110-0 01S),
D.01 -0 019j
0.D14.0.022
0.015 0025y
;0.D15 0028
0.017-0032)
[00017-0036
1
20-day
(D.005 0 DD7
[0,006 08
3A07 0O9)16
8 D
03
{0.009 0014
0.01D A 076
0.010-0 01B
0.01i-0 020
O.ffi10 0 022
30-day (0 004-D 6Dsj (4.00 IF 00,90�65 � '0006--0 008) (0.00fi 0 008 , 0.00 -0 010 [0.007D-0 011 0008-0 113)I { 008-0 014 0.005{] 01S 0{ 009-n Q18j1
45-day (600(0,004.0005) (0. 0 -0 006) 0.0�65 ff.0317} {0 008 0 008) {00D8 O U09) iff.008 0010] (0.006-0 011) 0.00 70 013)� 007-0 014]-
0 003 0.004 0.005 0.005 0.006 0.006 0.007 0.007 0.008 0.009
60-day
6.0D3 O.i]Q4) [O.DD3 D.dDS]I {0.004-0.005 O.DD4 0.00fi} {0.005 O.DUT) {0005.0:Df18) (0A05 D.009] {0_006-0.01� 4D�OD6 D.011 {0:006 0.012]
1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS).
(Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates
i(for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds
care not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values.
IPlease refer to NOAA Atlas 14 document for more information.
Back to Toa
PF graphical
10/17/2024, 10:15 AM
Culvert Report
Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.
Tuesday, Sep 23 2025
CULVERT 1
Invert Elev Dn (ft)
= 7762.56
Calculations
Pipe Length (ft)
= 55.00
Qmin (cfs)
= 12.00
Slope (%)
= 2.51
Qmax (cfs)
= 13.00
Invert Elev Up (ft)
= 7763.94
Tailwater Elev (ft)
= (dc+D)/2
Rise (in)
= 18.0
Shape
= Circular
Highlighted
Span (in)
= 18.0
Qtotal (cfs)
= 12.75
No. Barrels
= 1
Qpipe (cfs)
= 12.75
n-Value
= 0.013
Qovertop (cfs)
= 0.00
Culvert Type
= Circular Concrete
Veloc Dn (ft/s)
= 7.36
Culvert Entrance
= Square edge w/headwall (C)
Veloc Up (ft/s)
= 7.65
Coeff. K,M,c,Y,k
= 0.0098, 2, 0.0398, 0.67, 0.5
HGL Dn (ft)
= 7763.98
HGL Up (ft)
= 7765.28
Embankment
Hw Elev (ft)
= 7767.00
Top Elevation (ft)
= 7767.07
Hw/D (ft)
= 2.04
Top Width (ft)
= 20.00
Flow Regime
= Inlet Control
Crest Width (ft)
= 20.00
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Channel Report
Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.
SWALE #1
Triangular
Side Slopes (z:1)
= 3.00, 3.00
Total Depth (ft)
= 1.00
Invert Elev (ft)
= 1.00
Slope (%)
= 5.82
N-Value
= 0.030
Calculations
Compute by:
Known Q
Known Q (cfs)
= 4.30
Elev (ft)
3.00
2.50
2.00
1.50
1.00
0.50
0
Section
1 2 3 4
Reach (ft)
Highlighted
Depth (ft)
Q (cfs)
Area (sqft)
Velocity (fVs)
Wetted Perim (ft)
Crit Depth, Yc (ft)
Top Width (ft)
EGL (ft)
5 6
7
Tuesday, Sep 23 2025
= 0.55
= 4.300
= 0.91
= 4.74
= 3.48
= 0.67
= 3.30
= 0.90
Depth (ft)
2.00
1.50
1.00
0.50
M W
-0.50
8
Channel Report
Hydraflow Express Extension for Autodesk® Civil 3D@ by Autodesk, Inc.
SWALE #2
Triangular
Side Slopes (z:1)
= 3.00, 3.00
Total Depth (ft)
= 1.00
Invert Elev (ft)
= 1.00
Slope (%)
= 2.00
N-Value
= 0.030
Calculations
Compute by:
Known Q
Known Q (cfs)
= 0.40
Elev (ft)
3.00
2.50
2.00
1.50
1.00
0.50
0
Section
1 2 3 4
Reach (ft)
Highlighted
Depth (ft)
Q (cfs)
Area (sqft)
Velocity (ft/s)
Wetted Perim (ft)
Crit Depth, Yc (ft)
Top Width (ft)
EGL (ft)
5 6
7
Tuesday, Sep 23 2025
= 0.28
= 0.400
= 0.24
= 1.70
= 1.77
= 0.26
= 1.68
= 0.32
Depth (ft)
2.00
1.50
1.00
0.50
MM
-0.50
8
Calculation of Peak Runoff using Rational Method
Company. SoprkE [ minlmum-5 b
Oate:%0=25 GW ua[a su.l-cs7J(LI qc^mp^cea q-t=l,IFti H] — (°`a"� i5ele¢ed t]c=max(tminlmum ,min(Compuled Lc ,Regional Lc))
pra]eet:swesrwnrRRuael+ 73!(5.1^oa37 gc]_minlmam=lo(nen-arba")
Location: OARFIELOCA. Gabr trsel..y(snR-454t U BReglonaI tB c-(26-171)+ I.J/(60(141+9) Q(c(s)=clA
Ryn" CovtficiW,
C
Overland (Inhlal) Flow Time
Channellzed (Travel) Flow Time
Time of Concentration
NRCS
percent
OVeaaO
"'S
Elevallo
O/S Elevalion
Ovedantl
Oveaantl
Channellzed
UIS Elevation
D/S Elevation
Channellzed
NRCS
Channellzed
Channellzed
Computed
Reglonal
Selected
Subcatchmenl Name
Hydrologic
Imp—Tousness
Soil Group
25-yr
100-yr
d Flow
^
(R)
Flow Slope
Flow Time
Flow Length
(R)
(R)
1 Slope
Conveyance
Flow Velocity
FIoW TIme
1,(m1n)
4(min)
1,(m1n)
Length
e
(it)
(Optional)
$ (NR)
ti (min)
I, If)
(Optional)
(Op0onap
Sr (NR)
Factor K
V� (flf—)
t. (min)
(R)
BASIN 1
C
13 7
.0--�
0
141
7It44
7026
0.125
f fi7
7B2
7826
7764
0 079
7.0
1 97
6 fit
1549
2805
1 S
BASIN
C
zoo
033
Sz3
63
7774
7765
0127
0
110
T766W
776200
004
7.0
133
137
2670
aft. —
ROOF I
C
1000
0�
06�
5a0
ROOF2
C
1000
0
Ono
-
SW
ROOF3
C
1000
086
0F7
.500
I