HomeMy WebLinkAboutSOUTH SHIELDS VETERINARY CLINIC PUD - FINAL - 44-89B - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORT (2)FINAL DRAINAGE INVESTIGATION
FOR
APPLEWOOD ANIMAL HOSPITAL
FORT COLLINS, COLORADO
Prepared for
Dr. William Musslewhite
5001 South Shields Street
Fort Collins, Colorado 80526
March 20, 1990
Commission No. 1180-01-01-02
CONSULTING ENGINEERS
FOUNDATION ENGINEERING
320 N. Cleveland Avneue
Loveland, Colorado 80537
FOUNDATION I
ENGINEERING
Counsulting
Engineers
March 20, 1990
Commission No. 1180-01-01-02
Dr. William Musslewhite
5001 S. Shields Street
Fort Collins, Colorado 80526
Dear Dr. Musslewhite,
The enclosed report represents the results of the final drainage investigation
for the Applewood Animal Hospital, located in the Northeast Quarter of Section 3,
Township 6 North, Range 69 West of the 6th P.M., Larimer County, Colorado.
This investigation was based upon the proposed site development plan and plat;
proposed site development construction plans; on -site observations; and available
topographic information. The investigation was performed in accordance with the
criteria established in the City of Fort Collins -"Storm Drainage Design Criteria
and Construction Specification Standards" manual.
It is our opinion that the construction of the Applewood Animal Hospital is
feasible provided that the recommendations contained in the attached report and
the incorporated final design are performed in accordance with the final approved
plans for the project.
If you should have any_.questi
Respe u ly,
Kevin W. tterson,
FOUNDATION ENGINEERING
KWP/kmp
28$4i1
lease call.
320 North Cleveland Avenue 0 Loveland, Colorado 80537 • (303) 663-0138
i
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TABLE OF CONTENTS
Letter of Transmittal i
Table of Contents
Scope 1
Site Description 1
Existing Conditions 1
Proposed Development 2
Conclusions and Recommendations 2
EXHIBITS
Vicinity Map Exhibit A
Calculations Exhibit B
Drainage Plan/Site Plan Exhibit C
Preliminary Drainage Report Comments Exhibit D
ii
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E
S C 0 P E
The following report represents the results of a drainage investigation
for a proposed development to be known as the Laurie Subdivision, located
on a parcel of land situated in the Northeast Quarter of Section 3,
Township 6 North, Range 69 West of the 6th P.M., Larimer County,
Colorado. The investigation was performed for Dr. William Musslewhite.
The purpose of this investigation is to determine the effects of the
proposed development on the areas existing drainage conditions and to
determine the improvements, if any, and the appropriate sizing for
proposed improvements so that it may be incorporated with the
construction of the project. The conclusions and recommendations
presented in this report are based upon the proposed site development
plan and plat; proposed site development construction plans; on -site
observations; and the available topographic information. The analysis was
performed in accordance with the City of Fort Collins -"Storm Drainage
Design Criteria and Construction Standards" manual.
S I T E D E S C R I P T I O N
The site is generally rectangular in shape and contains approximately
eight acres, however, the sites East-West dimension is approximately
1,150 feet and its North -South dimension varies from approximately 390
feet at the westerly boundary to approximately 280 feet at the easterly
boundary. The site abuts the westerly right-of-way of South Shields
Street at a point approximately one-half mile south of Harmony Road. The
site is located on the Burns Tributary of the Fossil Creek Drainage
Basin. Only Lot 1 (Applewood Animal Hospital), is to be developed at this
time.
E X I S T I N G C O N D I T I O N S
The site is presently used as a large residential tract with the existing
structures located at the southeast corner of the site near South Shields
Street. The Pleasant Valley and Lake Canal passes through the adjacent
property to the north with a lateral of that ditch flowing through the
site. Near the center of the site is a ravine that has been created by
scouring action associated with an overflow discharge from the Canal as
it flows across the site toward the South. According to the irrigation
company's officials, the overflow to the ravine is designed to discharge
a maximum flow of 30 c.f.s. (cubic feet per second).
East of the lateral ditch passing through the site, the property slopes
gently to the East toward South Shields Street at a slope of
approximately 2%. The area below the ditch is irrigated and is used for
pasture except for the residence and out -buildings at the southeast
corner of the site.
1
The portion of the site that lies West of the ravine is not irrigated and
slopes rather steeply at approximately 15% toward the Burns Tributary of
Fossil Creek. The area is sparsely vegetated with ground cover consisting
mainly of native grasses and sage brush. The site abuts The Ridge
Subdivsion at the West and South.
The site receives run-off from the properties to the North and West. For
the purposes of this investigation, the area above the Pleasant Valley
and Lake Canal was not considered to effect the conditions onsite since
the ditch flow is controlled to the extent that there is an existing
overflow structure that directs excess flow to the ravine through the
site, as previously stated. The area to the North consits of
approximately 10.5 acres which drains easterly to South Shields Street
and then southerly along the west side of South Shields Street through
the site. An area of,approximately 2.5 acres drains into the smaller side
ravine that enters the site at mid -point of the northern boundary.
Approximately 4.5 acres drains directly into the major ravine before it
enters the site near the northwest corner.
P R O P O S E D D E V E L O P M E N T
The proposed construction is to consist of a vetinary clinic with
associated parking that is to be located on Lot 1, situate in the
northeast corner of the site adjacent to South Shields Street. A new cul
de sac street is to be constructed to serve the new clinic and the
existing residence. The cul de sac is to be extended to a circular turn-
around west of the existing and proposed construction in order to provide
access to the area to the West. At this time, development to the West is
not planned, however, future development is assumed to be single family
residential.
C O N C L U S I O N S A N D R E C O M M E N D A T I O N S
1. The proposed development will retain the existing drainage patterns
with only a culvert to be provided under Laurie Drive.
2. As South Shields will be reworked and widened to full width in the
near future, and the shallow nature of the borrow ditch in which the 24"
RCP is to be placed, we recommend instead the use of a 15 RCP. At the
time South Shields is widened, the RCP will be abandoned. Provide for
overflow of Laurie Drive due to 100 year flood.
3. The site is located in the fossil Creek Drainage Basin. The site is
not located within the floodway or flood plain.
4. All development is to be performed in accordance with City of Fort
Collins Standards and Specifications.
5. Onsite detention of stormwater is not recommended due to the sites
proximity to the existing "Major" drainage course.
2
0
6. Additional runoff from the Applewood Animal Hospital clinic travels to
the West drainage ditch, then flows south to Fossil Creek. It is our
opinion that the small amount of additional runoff from the site will not
require enlargement of downstream facilities.
N
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•
Dr. Mussleshite-Laurie Subdivision
By: DRM
Commission No. 1180-01-01-01
Date: March 20, 1990
Calculations for Drainage Investigation for Laurie Subdivision located in
the NE 1/4 of Section 3, Township 6 North, Range 69 West of the 6th P.M.,
City of Fort Collins, Larimer County, Colorado.
Total Site Area = 8 acres +/-
EXISTING CONDITIONS
Rational "C" Factor = 0.20 for Offsite Irrigated Areas
" = 0.25 for Offsite Steeper Non -irrigated Areas
= 0.25 for Onsite Irrigated Areas
= 0.30 for Onsite Steeper Non -irrigated Areas
PROPOSED DEVELOPMENT FOR LOT 1
Rational "C" Factor = 0.225 for Lawns and Landscaped Areas
" " to
= 0.95 for Roofs, Decks, Patios, etc.
ft to It = 0.95 for Streets, Drives, and Parking
Lawns and Landscaped Areas = 29,413 sq. ft.
Roofs, Decks, Patios, etc. = 4,400 sq. ft.
Streets, Drives, and Parkin; = 13,800 sq. ft.
Area of Site Consideration = 325' x 146.5' = 47,613 sq. ft.
"Q" avg = (29,413 x 0.225) + (4,400 x 0.95) + (13,8000 x 0.95)/ 47,613
"Q" avg= 0.50
Refer to following calculations for runoff'quantity determination
CULVERT SIZING
1. New culvert to be installed at cul de sac street from Shields Street.
The culvert is considered to be at "Inlet Control". Based upon the runoff
calculations the design flows at this point are: Q2=6 cfs; and Q100=20
cfs; therefore -
Using the Design Nomograph for Circular Pipe at Inlet Control:
@ HW/D = 1.0 and Q = 6 cfs an 18" dia. pipe will be sufficient
@ HW/D = 1.5 and Q = 20 cfs a 24" dia. pipe will be sufficient
USE a 15" dia. pipe due to site constraints
EROSION CONTROL
The primary area of concern is the newly graded area adjacent to Laurie
Drive at the inlet and outlet of the 15" culvert. We recommend these
areas be seeded with pasture grasses. This may require some type of "drop
structures" along its course and inlet and outlet protection at the
proposed culvert under the cul de sac street. Additional protection at
the inlet and outlet ends of the culvert at Shields Street should also be
L4
provided.
The City's Standard Erosion treatments for wind and storm -runoff should
also be incorporated during the course of construction.
•
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V�ICI�N�IT�Y ..... AP
EXHIIII "A"
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110
57
VICINITY MAP
EXHIBIT "A"
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�EXHiI�_:'IT "B"
FOUNDATION ENGINEERING
Calculated By:
DRM
STORM DRAINAGE INVESTIGATION
# 1180-01-01-02
Client : Dr. Musslewhite
Date : Dec. 29, 1989
RATIONAL METHOD PROCEDURE
Project: LAURIE SUBDIVISION
Checked By:
KWP
Design Storm: 2 YEAR Existing Conditions
Location
Point
Area
Runoff Coeff. Freq. Factor AxCxCf Flow Time
Flow Time
Rain Intens.
Runoff Comments
Description
Designation (acres)
C.
'Cf"
Tchan(min.)Tc
(min.)
"I"(in./hr.)"O"(c.f.s.)
Offsite Area 'A"
Pt. A
10.5
0.2
1
2.10
15
2.1
4.41
Onsite Area 1
Pt. A+1
2
0.25
1
0.50
20
1.85
0.93
Pt. A+1
12.5
0.2
1
2.50
20
1.85
4.63 Flow at west side of Shields flowing to south
Offsite Area "B'
Pt. B
2.5
0.25
1
0.63
10
2.5
1.56
Onsite Area 3
Pt. 8+3
1
0.3
1
0.30
10
2.5
0.75
Pt. B+3
3.5
0.26
1
0.91
10
2.5
2.28 Flow at "minor" ravine at north central area
Offsite Area "C'
Pt. C
4.5
0.25
1
1.13
10
2.5
2.81
Onsite Area 4
Pt. C+4
1
0.3
1
0.30
10
2.5
0.75
Pt. C+4
5.5
0.26
1
1.43
10
2.5
3.58 Flow from north and west- add 30 c.f.s. irrig
33.60 Total with irrigation flow
Onsite Area 6
Pt. 6
1
0.3
1
0.30
10
2.5
0.75
Total at Ravine
Pt. B+C+6
10
0.26
1
2.60
15
2.1
5.46 Flow exiting site - add 30 c.f.s. irrig.
35.50 Total with irrigation flow
Onsite Area 2
Pt. 2
1
0.3
1
0.30
10
2.5
0.75 Flow to south offsite overland
Onsite Area 5
Pt. 5
1
0.3
1
0.30
10
2.5
0.75 Flow to south offsite to 'major' ravine
Calculated By :
DRM
STORM DRAINAGE INVESTIGATION
# 1180-01-01-02
Client : Dr. Musslewhite
Date : Dec. 29, 1989
RATIONAL
METHOD PROCEDURE
Project: LAURIE SUBDIVISION
Checked By:
KWP
Design Storm:100 YEAR - Existing Conditions
Location
Point
Area
Runoff Coeff. Freq. Factor AxCxCf Flow Time
Flow Time
Rain Intens.
Runoff Comments
Description
Designation
(acres)
C.
"Cf'
Tchan(min.)
Tc (min.)
"I'(in./hr.)"O"(c.f.s.)
Offsite Area "A'
Pt. A
10.5
0.2
1.25
2.63
15
6
15.75
Onsite Area 1
Pt. A+1
2
0.25
1.25
0.63
20
5.15
3.22
Pt. A+1
12.5
0.2
1.25
3.13
20
5.15
16.09 Flow at west side of Shields flowing to south
Offsite Area "B"
Pt. B
2.5
0.25
1.25
0.78
10
7
5.47
Onsite Area 3
Pt. 13+3
1
0.3
1.25
0.38
10
7
2.63
Pt. B+3
3.5
0.26
1.25
1.14
10
7
7.96 Flow at 'minor" ravine at north central area
Offsite Area "C'
Pt. C
4.5
0.25
1.25
1.41
10
7
9.84
Onsite Area 4
Pt. C+4
1
0.3
1.25
0.38
10
7
2.63
Pt. C+4
5.5
0.26
1.25
1.79
10
7
12.51 Flow from north and west- add 30 c.f.s. irrig
42.50 Total with Irrigation flow
Onsite Area 6
Pt. 6
1
0.3
1.25
0.38
10
7
2.63
Total at Ravine
Pt. B+C+6
10
0.26
1.25
3.25
15
6
19.50 Flow exiting site - add 30 c.f.s. irrig.
49.50 Total with irrigation flow
Onsite Area 2
Pt. 2
1
0.3
1.25
0.38
10
7
2.63 Flow to south offsite overland
Onsite Area 5
Pt. 5
1
0.3
1.25
0.38
10
7
2.63 Flow to south offsite to "major" ravine
•
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Page 1
FOUNDATION ENGINEERING
Calculated By:
DRM
STORM DRAINAGE INVESTIGATION
# 1180-01-01-02
Client : Dr. Musslewhite
Date : Dec. 29, 1989
RATIONAL METHOD PROCEDURE
Project: SHIELDS STREET PROPERTY
Checked By:
KWP
Design Storm: 2 YEAR Developed Conditions
Location
Point
Area
Runoff Coeff. Freq. Factor AxCxCf Flow Time
Flow Time
Rain Intens.
Runoff Comments
Description
Designation (acres)
C.
V.
Tchan(min.)Tc
(min.)
"I"(In./hr.)"Q"(c.f.s.)
Offsite Area 'A"
Pt. A
10.5
0.2
1
2.10
15
2.1
4.41
Onsite Area 1
Pt. A+1
2
0.5
1
1.00
20
1.85
1.85
Pt. A+1
12.5
0.25
1
3.13
20
1.85
5.78 Flow at west side of Shields flowing to south
0=6 cfs for Culvert sizing
Offsite Area "B"
Pt. B
2.5
0.25
1
0.63
10
2.5
1.56
Onsite Area 3
Pt. 13+3
1
0.3
1
0.30
10
2.5
0.75
Pt. B+3
3.5
0.26
1
0.91
1 0
2.5
2.28 Flow at "minor" ravine at north central area
Offsite Area "C"
Pt. C
4.5
0.25
1
1.13
10
2.5
2.81
Onsite Area 4
Pt. C+4
1
0.3
1
0.30
10
2.5
0.75
Pt. C+4
5.5
0.26
1
1.43
10
2.5
3.58 Flow from north and west- add 30 c.f.s. Irrig
33.60 Total with irrigation flow
Onsite Area 6
Pt. 6
1
0.3
1
0.30
10
2.5
0.75
Total at Ravine
Pt. B+C+6
10
0.26
1
2.60
15
2.1
5.46 Flow exiting site - add 30 c.f.s. Irrig.
35.50 Total with Irrigation flow
Onsite Area 2
Pt. 2
1
0.3
1
0.30
10
2.5
0.75 Flow to south offsite overland
Onsite Area 5
Pt. 5
1
0.3
1
0.30
10
2.5
0.75 Flow to south offsite to "major" ravine
Calculated By:
DRM
STORM DRAINAGE INVESTIGATION
# 1180-01-01-02
Client : Dr. Musslewhite
Date : Dec. 29, 1989
RATIONAL METHOD PROCEDURE
Project: SHIELDS STREET PROPERTY
Checked By:
KWP
Design Storm: 100 YR.-Developed Conditions
Location
Point
Area
Runoff Coeff. Freq. Factor AxCxCf Flow Time
Flow Time
Rain Intens.
Runoff _ Comments
Description
Designation
(acres)
C.
"Cf.
Tchan(min.)
Tc (min.)
"I"(in./hr.)'Q'(c.f.s.)
Offsite Area "A"
Pt. A
10.5
0.2
1.25
2.63
15
6
15.75
Onsite Area 1
Pt. A+1
2
0.5
1.25
1.25
20
5.15
6.44
Pt. A+1
12.5
0.25
1.25
3.91
20
5.15
20.12 Flow at west side of Shields flowing to south
Q=20 cfs for Culvert sizing
Offsite Area "B"
Pt. B
2.5
0.25
1.25
0.78
10
7
5.47
Onsite Area 3
Pt. B+3
1
0.3
1.25
0.38
10
7
2.63
Pt. B+3
3.5
0.26
1.25
1.14
10
7
7.96 Flow at "minor" ravine at north central area
Offsite Area "C"
Pt. C
4.5
0.25
1.25
1.41
10
7
9.84
Onsite Area 4
Pt. C+4
1
0.3
1.25
0.38
10
7
2.63
Pt. C+4
5.5
0.26
1.25
1.79
10
7
12.51 Flow from north and west- add 30 c.f.s. irrig
42.50 Total with irrigation flow
Onsite Area 6
Pt. 6
1
0.3
1.25
0.38
10
7
2.63
Total at Ravine
Pt. B+C+6
10
0.26
1.25
3.25
15
6
19.50 Flow exiting site - add 30 c.f.s. irrig.
49.50 Total with irrigation flow
Onsite Area 2
Pt. 2
1
0.3
1.25
0.38
10
7
2.63 Flow to south offsite overland
Onsite Area 5
Pt. 5
1
0.3
1.25
0.38
10
7
2.63 Flow to south offsite to "major" ravine
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Page 2
DRAINAGE PLAN
EXMM.? M = IT ONI