HomeMy WebLinkAboutDrainage Reports - 02/04/1993I
l�
5-1h 5ub►M if-4a 1
Cory #( - vorvrlulA05 ('�
RevieweJ
Final Approved Report
"F�v.4L" Date7G3
DPAINAGE INVESTIGATION
FOR
A 11110POSE;D TACO BELL RESTAL'RAILU
FORT COLLLNS, CGLOFADO
Prepared for
150 East 29th Street
Suite 200
I o-vulaud, Colorado 8(;&38
J:;nu:uy i993
Project No. GI-M-010-99
PHERARED BY.
IR Engineering Associoies
150 East 291h Stre&, S404ie 225
Loveland, Colorado W536
7r4ephon:?: ,303i 663-2221
Civil and r v0.,Qnrnental EvQ:ole-eeing, Corsuifants
0
Engineering Associates
January 15, 1993
Project No. GRD-040-90
Mr. Al Hauser, Architect
ARCHITECTURE ONE
150 East 29th Street
Suite 200
' Loveland, Colorado 80538
Dear Mr. Hauser,
The enclosed report represents the results of the Final Drainage Investigation for the
proposed TACO BELL to be located on TACO BELL P.U.D., a replat of Lots 7 thru 10,
' Block 6 of the L. C. Moore's Second Addition to the City of Fort Collins, Larimer County,
Colorado:
This investigation was based upon the proposed site development plan and plat; proposed
site grading plan; 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 and incorporates the comments and concerns expressed through the review by
the City's staff.
Thank you for the opportunity to be of service to you. If you should have any questions,
please feel free to contact this office.
' Respectfully Submitted,
' Dennis R. Messner, P.E.
MESSNER Engineering Associates
' DRM/mkm
1
IEnclosures
I
1 Civil and Environmental Engineering Consultants
150 E. 29th Street, Suite 225 Loveland, Colorado 80538 Telephone: (303) 663-2221
I
TABLE OF CONTENTS
I
r
I
I
I
I
I
Letter of Transmittal
Table of Contents
Scope
Site Description
Existing Conditions
Proposed Development
Erosion Control Measures
Conclusions and Recommendations
Variance Request Letter
Vicinity Map
Offsite Contributing Area Exhibit
Existing Conditions Exhibit
Grading & Drainage Exhibit
Calculations
Drainage Summary
1
ii
ISCOPE
' The following report represents the results of a drainage investigation for a proposed
TACO BELL restaurant to be located on a parcel of land situated in the Southwest
' Quarter of Section 13, Township 7 North, Range 69 West of the 6th P.M., Larimer County,
Colorado. The site description is: Lots 7 thru 10, Block 6 of the L. C. Moore's Second
Addition to the City of Fort Collins. The investigation was performed for
ARCHITECTURE ONE. The purpose of this investigation is to determine the effects of
the proposed development on the area's 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.
ISITE DESCRIPTION
The site is rectangular and contains approximately 0.703 acres. The site's East-West
dimension is approximately 143 feet and its North -South dimension is approximately 213
feet. The site abuts the easterly right-of-way of College Avenue and the northerly
! right-of-way of Prospect Road. The site is located In the SPRING CREEK DRAINAGE
BASIN.
EXISTING CONDITIONS
The site presently consists of two separate uses. A brick structure is located on the
northern half of the site. This structure was originally constructed as a single-family
residence but has been used as an office building for the past several years. A TACO
BELL restaurant is located on the southerly half of the site at the Northeast corner of the
intersection of College Avenue and Prospect Road. The site slopes from North to South
toward Prospect Road at a rate of approximately 3%. The site does not receive run-off
from the properties to the North. The run-off generated on the adjacent property is
' directed westerly into the gutter of College Avenue or easterly into the alley. Run-off that
enters both the gutters in College Avenue and the alley flows southerly to Prospect Road.
A storm drain inlet is located at the easterly end of the curb radius on the northeast
corner of the intersection of College and Prospect. This inlet intercepts the flow from the
' North. Excess flow continues easterly along Prospect to Remington and then southerly
along Remington to Spring Creek.
IPROPOSED DEVELOPMENT
The proposed re -development of the site is to consist of remodelling and expanding the
existing residential/office structure located on the north side of the site. The renovated
structure is to be utilized as the "new" restaurant structure. The existing TACO BELL
' structure is to be demolished to to allow for parking, landscaping and driveways
associated with the "new" restaurant. The sequence of construction and demolition is
anticipated to be such that the existing restaurant will remain in operation while the
I1
Existing residential/office structure is being renovated. Other future improvement that
will ultimately effect the grading and drainage for the site is the proposed reconstruction
of Prospect Road. This construction is to provide channelizing and turning lanes to
1 improve traffic flow in the area. To perform these improvements the street is to be
widened. The curb and gutter is to be shifted to the North a distance of 15.5 feet along
Prospect Road to provide additional turning lanes. These street improvements will
require that the existing storm drainage inlet located at the northeast corner of the
intersection be reconstructed. The proposed grading and drainage plan for the site has
taken the anticipated future construction into account. The perimeter grades have been
established by continuing the crown slope grades of the existing roadway to the proposed
gutter locations.
The current City policies require that the difference between the historic rate of run-off
I and the developed rate of run-off be detained onsite. The release rate is to be no greater
than the 2 Year Storm historic rate. Due to existing physical constraints it is not
practical to adhere to the current criteria. These constraints are:
1. The City of Fort Collins desires to have the existing office/residential structure
renovated rather than allow the structure to be demolished. The requirement to
' provide handicapped access and the desire to have a "drive-thru" pick-up window fix
elevations based upon the existing structures main floor level.
2. The western side of the site is fixed due to existing curb, gutter and sidewalk along
South College Avenue. New access drives onto South College Avenue are to be
constructed. The new driveways are to meet the Colorado Division of Highways
' requirements concerning grading and drainage.
3. The eastern side of the site is fixed due to the existing alley grades, utility structure
locations and elevations and the adjacent residential structures.
4. The southern side of the site is to be lowered due to the anticipated widening of
Prospect Road. The access drive to Prospect is the controlling factor in determining
the "high water elevation" for detention onsite. To provide additional detention
storage volume there would need to be grades in the access drives more than 6%.
' The proposed increase in the overall amount of impervious surface is insignificant. The
total run-off that is to be generated on the site will be virtually the same as the present
I condition. A portion of the site, approximately 0.2 acres, is to be routed to and detained at
a new drainage inlet that is to be located in the parking lot adjacent to Prospect Road. The
entire site previously discharged undetained onto the adjacent streets. The proposed site
grading and drainage will reduce the rate of run-off that ultimately discharges from the
site and is therefore an improvement over the existing condition.
' EROSION CONTROL MEASURES
Erosion control considerations have been made based upon the short term, i. e., during
' construction activities and the long term, through the life of the facility. The long term
measures incorporated to eliminate erosion are the proposed methods and materials to
be used to provide a surface covering for the driveways, parking areas, walkways and the
' landscaped open areas. The structure and hard surfaced areas will provide a covering to
deter erosion. The landscaping to be established will be a combination of plantings and
ground covers to deter erosion.
' 2
' The short term erosion control method to be incorporated into the construction
requirements for the project is the placing of "Curb Inlet Filter Gravel' at the proposed
storm drain inlet to be constructed onsite. It is not considered as necessary to provide any
wind erosion measures due to the protected nature of the site. In fact, the project is
exempt from providing wind erosion measures since it is less than one acre in area. The
schedule for construction activities is anticipated to be: February 1 - April 30, remodel
and expand the existing structure; April 1 - April 30, perform access and site related
construction around remodelled structure; May 1 - May 7, demolition of existing Taco
Bell structure and existing drives and parking; May 1 - May 21, construct new parking
and drives, and install landscaping and signage. With this schedule the site will be
"open" and subject to water caused erosion for an extremely short period. This is due to
the desire to have the existing restaurant remain in operation while the other structure
is being renovated. The demolition of existing facilities and subsequent grading and
paving operations will be scheduled in a manner that will place the "new" restaurant in
operation as quickly as possible. Therefore, depending upon the sequence of construction
activities, the time elapsed between activities, and the weather conditions through the
construction period, it may be possible that no temporary measures will be required
1 (Please note that "Curb Inlet Filter Gravel' has been proposed for the inlet to be
constructed onsite adjacent to Prospect Road.)
CONCLUSIONS AND RECOMMENDATIONS
' 1. The proposed development will retain the existing drainage patterns.
' 2. The site is located in the SPRING CREEK DRAINAGE BASIN. The site is not
located within the floodway or flood plain.
3. All development is to be performed in accordance with City of Fort Collins
Standards and Specifications.
' 4. Onsite detention of stormwater is desired by the City of Fort Collins. The volume of
run-off estimated to be the difference between the existing and proposed conditions is
2,656 cu. ft. This is based upon the difference between the run-off from a 2 Year
' Storm with the site considered at the existing condition and the run-off from a 100
Year Storm with the site considered at the proposed conditions. It is not practical to
detain this entire volume on the site due to existing topographic conditions and
' physical grading constraints that are placed on the site. The grading and drainage
plan has been designed to assure that the proposed development will not adversely
impact the existing drainage system. The site grading design has been prepared to
reduce the area that drains directly into the street curb and gutter. This will reduce
' the run-off that flows to the East along the north side of Prospect Road. A detention
volume of approximately §,4_4 cu. ft. is to be provided onsite and the flow is to be
released at a rate of 0.7 c.f.s.
5. A variance to the City's onsite detention policies is requested in conjunction with this
report. (Refer to following letter.)
6. The City of Fort Collins Standards for temporary erosion control measures are to be
incorporated with the construction activities.
' 3
' Engineering Associates :2/4/Q3 Se4t--7-0
:7e /fie ice'-- January 15, 1993
Project No. GRD-040-90
1 Mr. Glen D. Schlueter •
Stormwater Utility
' City of Fort Collins
235 Mathews
P. O. Box 580 /
' Fort Collins, Colorado 80522 - 0580
' Re: Taco Bell Restaurant to be located at 1530 S. College Ave., Fort Collins, Colorado
' Dear Mr. Schlueter,
The subject project's estimated erosion control security amount has been determined to
' be the minimum amount required by the City of Fort Collins. Therefore, the owner will
need to include a $1,000.00 guarantee for erosion control with any other surety
requirements of the "Developer's Agreement."
' If you should have any questions or desire additional information, please feel free to
contact this office.
Respect ly Submitted, (/ C�/"'�
' Dennis R. Messner, P.E.
MESSNER Engineering Associates
DRM/mkm
CC: Mr. Al Hauser, Architecture One
1
Civil and Environmental Engineering Consultants
150 E. 29th Street, Suite 225 Loveland, Colorado 80538 Telephone: (303) 663-2221
Engineering Associates
November 27, 1991
Project No. GRD-040-90
Mr. Glen D. Schlueter
Stormwater Utility
City of Fort Collins
235 Mathews
P. O. Box 580
Fort Collins, Colorado 80522 - 0580
Re: Taco Bell Restaurant to be located at 1530 S. College Ave., Fort Collins, Colorado
Dear Mr. Schlueter,
This is to request a variance from the City of Fort Collins policies concerning storm
' water detention for the proposed TACO BELL to be located on Lots 7 thru 10, Block, 6 of
the L. C. Moore's Second Addition to the City of Fort Collins, Larimer County, Colorado.
' The specific request is that the City not require onsite detention of storm water for this
specific proposal. The following are reasons why it is felt that the use of onsite detention
for this particular site is impractical.
1. The City's desire to utilize the existing structure at this address fixes the elevations
that may be considered for finish grade around the structure. The requirements for
"handicapped access" fixes the elevation from the parking lot to the South. The
owner's desire to have a "drive-thru" sets the elevation to the North.
2. The western side of the site is fixed due to the existing curb, gutter and sidewalk
along South College Avenue. A new access to South College Avenue is to be
constructed. This new access will meet the requirements of the State Division of
Highways and will be graded to direct all run-off to remain onsite.
3. The eastern side of the site is fixed due to the existing alley and utility structures
within the alley.
4. The southern side of the site is anticipated to be lowered due to the proposed widening
of Prospect Road to allow for additional lanes for thru-movement, left -turn and
right -turn. The proposed access drive to Prospect Road does not allow for sufficient
grade change to grade the site in a manner that will retain run-off on the site.
5. The proposed changes in the overall amount of impervious surface are insignificant.
The total amount of run-off will be virtually the same as the present conditions.
6. The proposed site grading will route a portion of the run-off to an inlet located in the
parking lot onsite. This will reduce the overall flow that ultimately concentrates in
the gutter at Prospect Road and thereby be an improvement over the existing
condition.
Civil and Environmental Engineering Consultants
150 E. 29th Street, Suite 225 Loveland, Colorado 80538 Telephone: (303) 663-2221
' Page 2
Nov. 27, 1991
GRD-040-90
' We will sincerely appreciate your timely response to this request. If you should have any
questions or desire additional information, please feel free to contact this office.
Respectfully Submitted,
Dennis R. Messner, P.E.
MESSNER Engineering Associates
DRM/mkm
I
[_1
k
[1
I
I
I
j7
I
I
I
[1
I
I
I
I
I
EX�HI :ITS
I
I
I
I
I
I
I
I
I
I
I
I
I
I
LI
I
I
I
r
' :._ VICINITYMA
r ,�> ',�G✓r (ter ! f � /
s'.rl
�.
1 MGM,. Mtn
I
Or
i•f ti�7,� iw•..: i'A .: vEpp
s..
• f=' y
HXDI I-FGE—AVEME
0
IF SI? I
r-LOWUOE - ?> 1 �14
> LP
Im
u, SZ13 C,c = 0 010
FLOWLI
0 lSAO ZI ZO er
z
Ow CURB, 0 V*,LK
.��TTEK 4 SPE oil
I
r\T
U1.
0
In
0 'n
WW
Z:
(n
ul i Z (n
O jj : /g,7 o
0 M, -- ------
rr\
0-
f- -n
-4F
.000
040- 0
0
47.0
oc 'r
X ON V,
x
'011
po
0 5.0
w
SP M
0 -n LA to 4 20
)> m
CO)
0) 0
-n rn 70 too
r- -70 kN X D p fp <
x (:) . rn
INA 0 0 ('s m
X
b rn L
Ur 70
G, co)"d T- .0 A
-4 T rn A 6\
c
An 0 %
-4 T-
P 60.9T. rn
�O IIX
CAU) s.d
4z. ca
com 79 ...... p
7
98 0
—10
0 >
4 do, .,:!
VS)VI— / , ?1 0 >; : ... 9 0
m �rn c
m
m
0 4,)
D>
C5
ro :X) A-
> >0000
'Coll m
c
to
z
En O n w C- 0
CA C-5
Cb
-4 xo �
(inns
?
t5-v Gb rm
T-
70
ng
bo II 0
ca
ig
ve
0
0
>
Wo6p j HASOJF%( Fr_C
o
0SJO 04, = OOLO oL'O
cZo ALLEY' Old 311SAJO
C) v CLOOMV38V 1% -.z
DVLC"OmV3UV Nl�
S130.
I
1
F
1
I
i
1
11
11
1
1
1
I
i
1
i
CCAlCOVI&ITI ONO
i
' Client: ARCHITECTURE ONE Project No. GRD-040-90
By: DRM REVISED: Jan. 15, 1993
Calculations for Drainage Investigation for Lots 7 thru 10, Block 6 of R. C. Moore's 2nd
Addition located in the SWV4 of Section 13, Township 7 North, Range 69 West of the 6th
' P.M., City of Fort Collins, Larimer County, Colorado
Total Site Area = 0.703 ± acres of existing platted property
The proposed development of the site is to consist of demolition of the existing structures
on the site and the construction of a new TACO BELL restaurant. The site will be
required to dedicate property along College Ave. and Prospect Road due to proposed
street widening projects proposed to occur in the near future. The net area of the site
after right-of-way dedication is anticipated to be:
Net Site Area = 0.634 ± acres
1 EXISTING CONDITIONS - RUN-OFF COEFFICIENT
Rational "C" Factor = 0.20 for Lawns and Landscaped Areas
= 0.95 for Roofs, Decks, Patios, etc.
= 0.95 for Asphalt and Concrete Streets, Drives, and Parking
= 0.50 for Gravel Streets, Drives, and Parking
' "C"avg (Existing) Lawns and Landscaped Areas = 3,728 sq.ft.±
Roofs, Decks, Patios, etc. = 7,649 sq.ft.±
Streets, Drives, and Parking = 12,196 sq.ft.±
Gravel Drives, and Parking = 7.050 sq.ft.±
Total Site = 30,623 sq.ft.± = 0.703 ± acres
"C" avg = ((3,728 x 0.20) + (7,649 x 0.95) + (12,196 x 0.95) + (7,050 x 0.50)) 30,623 = 0.755
"C" avg = 0. 755
PROPOSED DEVELOPMENT - RUN-OFF COEFFICIENT
"C"avg: Lawns and Landscaped Areas = 7,490 sq.ft.±
Roofs, Decks, Patios, etc. = 2,825 sq.ft.±
Streets, Drives, and Parking = 20,308 sq.ft.±
Total Site = 30,623 sq.ft.±
"C" avg = ((7,490 x 0.20) + (2,825 x 0.95) + (20,308 x 0.95)) 30,623 = 0.767
"C"avg = 0.767
TIME -OF -CONCENTRATION
Time of Concentration (Roof to Ground) = 5 minutes
Time of Concentration (Ground to Street): Tc(min.) = 1.8 [ 1.1- (Cf x C) ] �L(ft.) - 34S(%)
Time of Concentration (Street Flow): T(min.) = L(ft.) - [Vel. (ft./sec.) x 60 min./sec.]
Totaal = Txoof + Tc + Ts
IPage 1 of 8
1 Client: ARCHITECTURE ONE Project No. GRD-040-90
By: DRM REVISED: Jan. 15, 1993
' EXISTING CONDITIONS TIME -OF -CONCENTRATION
' Tc = 1.8 [ 1.1 - (0.755 x 1.0) ] 480 + 342.9 = 3.75 min.(Overland Offsite to North)
Ts = 350 = [ 2.5 x 60 ] = 2.33 min.(Street Offsite to North)
' Ts = [230 -t- (3.5 x 60) + 150 � (2.5 x 60)] = 2.10 min.(Street Adjacent to Site)
' TTota] = Ts +Tc + TT Therefore, T = 2.33 + 2.1 + 5.00 + 3.75 = 13.28 min.
USE 10 minutes as Time of Concentration for Point of Concentration located at the
' Southeast Corner of the Site
12 @ 10 min. = 2.50 inJhr. Iioo Q 10 min. = 7.25 in./hr.
RUN-OFF
Run-off, Q = C x I x A x Cf
Cf at 2 year Storm = 1.0 Cf at 100 Year Storm = 1.25
1 RUN-OFF FROM SITE AT EXISTING CONDITIONS:
Q2 = 0.755 x 2.50 x 0.703 x 1.00 = 1.33 c.fs.
Qioo = 0.755 x 7.25 x 0.703 x 1.25 = 4.81 c.fs.
RUN-OFF FROM SITE AT PROPOSED CONDITIONS
Q2 = 0.767 x 2.50 x 0.703 x 1.00 = 1.35 c.fs.
Qioo = 0.767 x 7.25 x 0.703 x 1.25 = 4.89 c.fs.
I
The estimated detention storage volume based upon the current
City criteria is indicated on the following page. (Page 3 of 8)
Page 2 of 8
'
"RATIONAL
DETENTION VOLUME DETERMINATION
FOR METHOD"
'
Q100
Volume
Q Released
Volume
Volume
Time
Proposed
® Q100
Q Q2
Released
Difference
(min.)
(c.f.s.)
(cu.ft.)
(c.f.s.)
(cu.ft.)
(cu.ft.)
10
4.89
2932
1.33
798
2134
15
4.04
3640
1.33
1197
2443
2D
3.50
4206
1.33
1596
2610
25
3.10
4651
1.33
1995
2656 Max. Vol.
30
2.80
5035
1.33
2394
2641
'
40
50
2.36
2.02
5662
6066
1.33
1.33
3192
3990
2470
2076
60
1.75
6309
1.33
4788
1521
At Q2 Existing, Q = CIACf = 0.755
x 2.50 x 0.703
x 1.0 = 1.33
At Q100 Proposed, Q = CIACf = 0.767 x I x 0.703 x 1.25
CACf = 0.767 x 0.703 x 1.25 = 0.67
i
Therefore, the Detention Volume desired is 2,656 cu. ft. based upon a release
rate of 1.33 c.f.s. This would conform with the City's criteria for storm water
detention which is based upon detaining the difference between the run-off
generated by a 2 Year Storm event (with present site conditions considered)
and the run-off generated by the 100 Year Storm event (with the proposed site
conditions considered.)
NOTE that it is not possible to detain the desired volume of run-off on the site
due to existing topographic conditions and grading parameters.
LJ
ARCHITECTURE ONE
TACO BELL
Proj. No. GRD-040-90
' Page 3 of 8 (Rev. 12-14-92) DRM
i
I
I
I
I
I
I
I
I
I
cV
N
t-
O
'"'i
GV
v
O
N
i--i
C
M
m
M
m
tO
CV
tO
Ci
LOO
CV
CV
xO
CV
u
C
U
o ,�
�
,o
,o
0
0
0
0
0
d
� v
E-F
c4..
U
x
U
N
m
CV
cq
v
N
v
CD
o
.�
m
x
o
o
c
o
c
o
c
)w
U
x
c
cq
ccq Ni
m LO
IV
o
x
x
o
o
c
o
c
0
W U
O
8
O
O
O
$
w
w=
a) U
O
CD
O
CD
O
CD
N
M
cc
N
Lo
OO
O-
U "
o
0
0
0
0
0
a) )„
cD
cM
CD
m
m
d'
L
N
O
C 00"
c
c
a (D
A
a�
y
U1
U]
(1am')
C �
G O
O ii
N
y
y
O W
(D
N
o
O
a�
1
0�
M
O
m
d0',
l—
9
N
_
VD
N
m
co
c6
O
m
►-i
N
N
CV
CV
N
CV
N
N
N
N
N
N
N
N
ti
Q
O �
U
o
in
,o
0
0
0
0
0
�
d
E-4
w
'U
x
U
co
w
W
N
iO
LO
m
!O
O
w
U
x
U
to v
N
N
O
(D
k
o
0
0
0
c
o
U
LL
in N
CC9
cq
NN
N
w
a)
CD
CD
CD
W
CD
N
to
m
U "
0
0
O U)
M
V;
)O
O
0
C
O
O
O
0
A
a�
Cq a~i
ai d
.4
0
�U]
C1)
o
U O
O y
U a)
U >>
U
e"i
aoi
c yz
oZ�UjdO
a�
6h a
w
r
.3(9)
+ y
o
1
tea".�aco
ono
°
cn
0�
F
I
I
I
11
I
O N 4
LN
N
t-
�
c�
�
m
•
--�
O
--�
"�
O
O
O
r4
M
m
O
O
O
O
10
O
=
v
m
m
CV
CV
CV
CV
CV
Ci
U
O �
U '
o,C,n
(D
F
w
U
x
U
c-
c1
N
d
m
co
N
ti
O
cy
O
'r
0)m
C-
k
O
O
O
O
O
O
O
O
w
U
x
�mmmti`vc
c
x
w�0
0
0
0
0
0
0
w
U
m
m
N
N
00
O-
U -
O
O
C
O
C
G
C
N
d O
F. F.
co
m
co
N
M
�
� C
Pa
U
cv
m
Idq
O
a �=
as
at
A
d
o
oo
oU
o �iU
a;U
>U
>+4U
CO
rn
W Cj
Z
w4JFq
z
ca
N 4
M
O
�
m
la
m
m
N
-
v
m
CV
m
CO
4
CV
O
c-�
o--�
N
CV
N
N
N
N
cV
cV
lz
t�
tz
U
O r.
U
O
in
0
0
0
00
0
0
F
w
U
x
U
O
d
00
cV
O
O
N
00
CV
CV
N
m
m
O
O
k
O
O
O
O
C
O
C
O
w
U
x
U
,-:r
N
N
v
N
M
1-4
x
o
0
o
c
o
0
0
rX4
cl
cl
,�
cl
cl
a, -
w
O
0
n
N
N
d (�
O-
co
cO
o
c0
C
G
C
000
O
U -
O
0
C
N
O FU„
.ti
co
l—
m
to
m
m
v
m
CV
m
m
N
C
O
C
O
O
O
O
Cq
m
vm
cn
v
at
A
►
d
:t�
o
o
C
O OD
o
o
o
.� .�
y W
G U
W
o
U 4)U
�U
y'gU�
QD��
oWC/)
os
O
O N
N
$®O
N
a
aS
a�.a
a)
►
a)
r
cOw
-y�
CA
�o
0
3(g)0
0 o�
0
w
w
0
a
Client: ARCHITECTURE ONE Project No. GRD-040-90
By: DRM REVISED: Jan. 15, 1993
' Based upon the previous calculations, the flow in the gutter on the North side of Prospect
Road at the southeast corner of the site is estimated to be:
iQioo Existing = 8.22 c.f.s. Qioo Proposed = 7.20 c.f.s.
1 THEREFORE, THE RUNOFF FLOWING IN THE GUTTER TO THE EAST OF THE
SITE WILL BE NO GREATER THAN THAT AT PRESENT.
SIZE INLET IN PARKING LOT
From Fig. 5-2 with 6" deep opening and 6" depth of flow in gutter
Q/ft. = 1.1± cfs/ft.
with 4' long opening Q = 1.1 x 4 = 4.4 cfs
Reduction Factor for sump condition = 80%
Q allowable = 0.80 x 4.4 = 3.5 cfs >> 0.43 & 1.56
Therefore, 4 ft inlet is OK
SIZE PIPE
Q = 1.486/n A R*2/3 S*1/2
Consider 15" dia. Pipe Q 1.0 %
Q = 1.486/0.013 x 1.23 x 0.46 x 0.1= 6.47 cfs>>0.43 & 1.56
Therefore, l5' dia. is OK
DETERMINE DETENTION VOLUME
' High water Elevation = 89.40
Therefore, area detaining water is the parking bay at the southerly side of the site plus a
small area in the landscaping to the South of the parking bay.
Vol. =M18x0.5/2)+(18x0.9/2)]=2x81)+U4x0.4/2)+0]=2x81]=542.7cu. ft.
DETERMINE DISCHARGE RATE
I Based upon the available detention volume the discharge rate is determined to be
Q dis. = 0.69 c.fs. (See the following page for calculation.)
Page 6 of 8
T4,60
oms
�tTaN r,o a
Vdt,um�
p$Q ✓h i) I•� IOP Ot- CUrIo 6 alO C-14.0
i .
Opp (3E,QM �� t
Qloov-C Tole..
I
S�cT•oR1 !vast
_ Too a sq,4A
rem
-12
'}-
1�-
[1
1
1
1
1
1
1
I
1
1
1
1
DETERMINE RELEASE RATE FROM PARKING LOT DETENTION
Q100
Volume
Q Released
Volume
Volume
Time
Proposed
@ Q100
® Q2
Released
Difference
(min.)
(c.f.s.)
(cu.ft.)
(c.f.s.)
(cu.ft.)
(cu.ft.)
10
1.56
938
0.69
414
524
15
1.29
1165
0.69
621
0-Max
20
1.12
1346
0.69
828
518
25
0.99
1488
0.69
1035
453
30
0.90
1611
0.69
1242
369
40
0.76
1812
0.69
1656
156
50
0.65
1941
0.69
2070
-129
60
0.56
2019
0.69
2484
-465
C C- T A
At Q100 (Proposed), Q = CIACf = 0.767 x I x 0.225 x 1.25
CACf = 0.767 x 0.225 x 1.25 = 0.22
Per the Grading and Drainage Design the Maximum Detention Volume
available is 543 ± cu. ft.
Vol.
The release rate, "Q Released @ Q2," has been determined by performing the
above calculations through several iterations in order to obtain the maximum
available detention volume.
The allowable release rate, Q =
Page 7 of 8
0.69 c.fs.
ARCHITECTURE ONE
TACO BELL - P.U.D.
Proj. No. GRD-040-90
(Rev.12-14-92 DRM)
Client: ARCHITECTURE ONE Project No. GRD-040-90
By: DRM REVISED: Jan. 15, 1993
DETERMINE ORIFICE SIZE
Orifice Equation, Q = CA42gh
A=Q=C42gh
Q = 0.69 c.f.s. (from Page 6) C = 0.65
h = 89.40 - 86.62 = 2.78
A = 0.69 + [0.65 x 4( 2 x 32.2 x 2.78)] = 0.079 sq. ft.
A=w*2 w=4A
w = 40.079 = 0.281 ft. = 3.37 inches /
Therefore, Use 3-3/8" z 3-3/9' as Maximum Orifice Opening
Page 8 of 8
.i
' CONSTRUCTION SEQUENCE
PROJECT:. TACO BELL - P.U.D. STANDARD FORM C
Revised
' SEQUENCE. FOR 19 93 ONLY COMPLETED BY: Dennis R. Messner DATE: Dec. 15, 1992
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
MONTH ---------
OVERLOT GRADING
WIND EROSION CONTROL
Soil Roughing
Perimeter Barrier
Additional Barriers
Vegetative Methods
' Soil Sealant
Other
I
1
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'
S
1993
Jani•FebL Mar. Aprl. MayJ Junel Julyl Aug.J Sept. Oct. Nol. Dei
•
.....__•.......................0---------------------
XXXX
NO Wind Erosion Control Measures are required
due to the size of the lot.
od Installation xx xx
Nettings/Mats/Blankets
Other
' STRUCTURES: INSTALLED BY
NOTE that the majority of the construction time period
will envolve the remodelling of the existing structure
....--- .............. ....... ..... ............. .------------ •--
without disturbing the remainder of the site and existin
restaurant.
MAINTAINED BY
VEGETATION/MULCHING CONTRACTOR
' DATE SUBMITTED APPROVED BY CITY OF FORT COLLINS ON
IHDI/SF-C:1989
I
II
RAINFALL PERFORMANCE STANDARD EVALUATION
PROJECT: TfjG(, ���� STANDARD � FORM A
A*V.
COMPLETED BY: /NE sma a Fyo p, tito". � jyJ. DATE: /2-16.9Z
DEVELOPED
ERODIBILITY
Asb
Lsb
Ssb
Lb
Sb
PS
SUBBA$IN
ZONE
(ac)
(ft)
($)
(feet)
M
M
2
MAder e
6,Z3
.64
e,4
a 3 3
2
317 %
—
s 6
---�
g2,
l 9
D#.7a
MARCH 1991 8-14 DESIGN CRITERIA
o� I
I
I
I
.I
I
I
I
I
i
[l
I
I
I
I
I
I
I
I
EFFECTIVENESS CALCULATIONS
PROJECT: TTANDAR'% FORM B �9co lE�� � � . c�.
COMPLETED BY: Mc�t!Uy��P �E-vgd DATE: lZ /5-?
Erosion Control C-Factor P-Factor
Method Value. Value Comment
?>Are Soy ,
W e+ F; 1 }eP , O D
Sirue.+U-g,.
MAJOR
PS
SUB
AREA
BASIN
($)
BASIN
(Ac)
CALCULATIONS
SttfAeAwC.-- 01624c-
LaW� Dto ac. 134+e So11 2nc.
O1tC®.A4��'(A.OIIIt+.AZ�+(O.AI?� '
I,O A a 6A : pe 1 VIL
= o' I5
Y.
100
# Z
otn
r'. Ewa vas 0•02 AG �•�SLT�' } �:2I at.
(jirw�G1 F�1�lY
1
w = Cto.at no,OZ.) } L1,4 X �,21� 6,23
= 0.91
w+/d'P' = I,o x 1.0 A a4$ = o,�o
EFt = �, — C6180 K 01-11�1 v- IOD = 27,2. 'a
�t3.
0133
Ia,►ew.� = o . o u�. 'S4v%.< U A- o, oSac.
BA-C. So:1 o► 1°I ac.
'U +�` _ ��O+o1xo,Q1)1- C,ol x 0,05)+L•oIx c
4'fid'P+ ' D.��>L I,d ac►�a xl,o = OI$
i.Atm)
IMARCH 19$1
8.15
DESIGN CRITERIA
I o� 2
1
1
1
1
EFFECTIVENESS CALCULATIONS
PROJECT:
TAG o TANDARD4ORM B
COMPLETED BY: _ /ljFS.xNEr2 �'ylm� A3SVG. K DATE: /2�-/T�-�IZ�
Erosion Control C-Factor P-Factor
Method Value Value Comment
MAJOR
PS
SUB
AREA
BASIN
(t)
BASIN
(AC)
CALCULATIONS
CO"4')
4.3
To*M
6 /7
5-
��a, i`f >< $g,0) +-00,23 x
070
/✓ale ,�hti� ,�ti�.s Qp�4 �,�t
be o/4en 41,4,0�oxoromf�f, 3 u,gekr
ANtI 7��1,e. � D�hl� .TOtm.t U
re�14es�e�'
' MARCH 1991
8-15' DESIGN CRITERIA
z4z
[]
DRAINAGE SUMMARY
for
Proposed TACO BELL Restaurant to be located on Lots 7 thru 10, Block 6,
R. C. MOORE'S SECOND ADDITION to the City of Fort Collins, Colorado
Existing Conditions:
Total Area = 0.703 ± acres Onsite +
Rational "C" factor = 0.755 (Onsite)
Onsite Run-off: Q 2 = 1.33 c.f.s.
Offsite Flows: Q 2 = 2.87 c.fs.
Total Run-off: Q 2 = 4.20 c.f.s.
Developed Conditions:
1.69 ± acres Offsite = 2.39 ± acres
Qioo = 4.81 c.fs.
Qioo = 10.39 c.f.s.
Qioo = 15.20 c.f.s.
Total Area = 0.634 ± acres Onsite + 1.76 ± acres Offsite = 2.39 ± acres
Rational "C" factor = 0.850 (Onsite)
' Onsite Run-off: Q 2 = 1.35 c.fs. Qioo = 4.89 c.fs.
Offsite Flows: Q 2 = 2.87 c.fs. Qioo = 10.39 c.f.s.
' Total Run-off. Q 2 = 4.22 c.f s. Qioo = 15.28 c.f.s.
' NOTE: There is no appreciable difference between the run-off from the
"Existing" and the "Proposed" conditions.
Detention Summary:
' On site detention facilities are proposed to the physical extent possible.
' Site run-off is to be discharged into the existing Storm Sewer located in
Prospect Road adjacent to the site's Southerly boundary.
' Drainage Basin Statistics:
Gross Platted Area: 0.703 ± Acres
Gross Area Rational "C" Factor: 0.767
Net Platted Area: 0.634± Acre
Net Area Rational "C" Factor: 0.850
Onsite Detention: Desired Vol. = 2,656 cu. ft. Plan Vol. = 543 cu. ft.
(856.5 c.f./ac.)
Peak Discharge from Detention = 0.69 ± c.f.s.
Basin: SPRING CREEK
PLAN \VIE,W VERTICAL CURB, GUTTER AND SIDEWALK
r-wro.w
SECTION A -A
NEW DRIVEWAY APPROACH DETAIL
(S. COLLEGE AVE.)
Q°'""'kl ff��N1nuL1 BtrA
wn5ux OW
nANwtw
pwfw WIwMVM.r
A.ur
Wm4r.
r. •vNrs6,e uM
SSrKKI A A
Notmi
aP•, A
so
No A. Is No2. v1tI n�STOP,r I no
lrn, nVo ., or eae.
Ploee Curlplinlet III lrer Grovel of let the OR FOR been cam their and IN germane
is at quargrado. Remove In weer to place pov n9 ON replace after par n9 -e
ponnsel d11M Filter is to nmeln In piece until SC%of the site landscopin9
Is M PI
it OOMMON,
m:•a�
Ross
RAN.51W
:.�: ...,•Veer
No 4M .:.FORK "'
'IT"1 oeu± 00 r•
I
T� T Ytt" AA PLAO
m� Sal
I'I rON. OL, ..A.
�IIWFId
1
ma
i®II
j, PERSPECTIVE VIEW
SI `Nft-
r-70
,5,:
- ,SECTION A A
let fr Meet ts'.
NEW DRIVEWAY APPROACH DETAILS
VERTICAL CWN AND OLIVER
(PROSPECT ROAD)
y
-v win W
1�24
,y....
F
T-Jm
I40r�
Lei
aNr
Nb
CURB AND GUTTER DETAILS
CLEAN a 9900144
r
•Pill Immeen.
TOM O"LlInk
•. 'IT"..rw,. ,
14
SECTION A -A
9EODINO REOYIREMENTS
OFFOME AREA Y+O.alm.
eR+LELLa
M /
YYR�
IeRMt Met OxRa-
an , raarwv.T m.E
role FeLtnrALL
Ij\ W"M
I Lecva6ra
txeARaae earl
IrTmnur
ZW
I
X r `
OFFIITE AREA 'Y' IDOTye
OE' OIDJ a
E.Qts
I fLHTi1MlIW
T I'pwrr nTFCNJ _
W T I
OcclPOIN
LF� e Y u
in
W ALL
he
ItDaNTSu
YM
u 6AR e
s ¢w w
y rr.P,L®®_-, I u'vAm®i r]°XO'mr_6uaYa n
] O A xSwEmCNTN
INTO I M '"""_ei
bA Y
tlM'E a e'b 1115
YYe
^mow m .
amxL
4 Art
ro s Iwo ergo Low"
EYyK MrryID I Mw OE:O.O eta
Opy A4a
G.Y w OFFT LIA% R^.0]l06
•. I Y!]aCY aBER aMVY ` I ONp.40aSX
♦ao. me
ron6 O -- pTnIRC
'Y 1
a E 9 wm ore, ]ly Ygr
II�n1AIX PY�11V1
W.
: H Oman Yi9R �
ryy.EM1E}Ya,(fy.3 I mMR
IAR'E0A0.0,12
M Ot :]ea A
L e OEaY.DetBex
tDa]P...
a. aROADver _ LTL-- —-------�--- ate
TM1 aM1aEeE' b ntlX planIndicateslX0 "Than Of the 01U to b0 udfor
ITVPC
t SADfor Wale C "ti ~ When Water Elevationa 99 d01 - —s
Rt'IEaN II let desUro in I
._-
C�RADINCz DRAINAGE PLAN NORTH
BCALEr O•
LEGEND ""b' gwtRprrc
a Em rt MN
18"ST _ Existing Storm Drain Pipe (size indicalsd) e� m _ to al w I" nb in
mRrll.l,
y w city
93
Proposed Finish Surface Contour Lins
met
e W63'
Proposed Spot Elevation at Finish Sun ace
- .
Los"
Oil
tb3
Existing Spot Elevation at Surface
"Nwhirr Ever
ryxyMrt
,rn
ow
83,47 FL
Existing Spot Elevation at Flowline of Gutter
MVML tARbg
switches,
123 SO
Existing Spot Elevation at Back of Wall
Hi itt imP'Mr
It
WIN "Thint
mitt FOKO stores
91.63 TIN
Existing Spot Elevation at Top of Wall _
sex se ir,N.n,w
123.1/
Existing Spot Elevation at Top of Curb`
1.33 T1
Existing Spot Elevation at Tap of Pavei@ent
It MM
Proposed Curb and Gutter (Sid. Inilavl Gutter)
ftyk'ii
lyg reetil
Sw
ML TIN'
1aRRRfpaPRRlip
Proposed Curb and Gutter (Outflow GNrtev)
1
r H FPoEESO
m9TPRPoT� EXIST F PoLE
TO as RKMAFO
--an
IW OINILR91
PROSPECT ROAD 1acti 2")
ro a�°ipL rl ambLTXb gvfaT-aTUaC'N dl KcrxM MOIVve
"f ORK CHOP" DETAIL
f^--- le- _A,, q^ \— OUFpEPIIATE
IST_1S dustdust89t a.1W die. STORM DRAIN SM DNII IEelown)
DRW � S I.W% L kJ
p1IFA11 � \ U
z
Z_
SECTION Ctil PROPOSED STORM DRAIN
- 11 (Net loScale) V
rgml RT Obeid "fe'Dl0"I Pq.
wMI pYb 0{OR Yver IV DM NIOC
e I UJ
UJ
b WENT Z
nth NIMIW P)FWI.i PAWFAE
We N eM P1W 1(SPrxt GP/CWENRP{I �ty W
tire
p^s 6NNMUV1C 9 5 _ Y RxcrAaa"L feuEm`eP-'NsOPg Y.o T
9�1 DPPxencylQWW
J
O
LATE DETAIL PAVEMENT DETAIL _U
Nil ,o-song Olt lo-9vala
'EN RAL NOTES: _ -
Q
I, rerb the appravM P.U.D.3ile Rm brparMry bt ayout dmensbns: 0
2 rid SM1Nl E old Cwtom UPllty Plan has pawmenl preacen9 ratpiremma (See TVJ'ICAL p.
T ENCH'Di two
... a.. ToAxIsfing yRXXwyWp ement swaort baled In C011o Avenue QhWI mite Ilaunted lA'oM
e sodatetl with campag the gustN cap This or mnslruNo9 IN IMgiosed Diversion,Appll hm
r re nr ro, TVw w +r J(11 OB parbrm6d W IMul distulbhy; the asking mmmig pa inkni 66aloo.
It
Conimoor shallN reg ae
Irw cancel wol,an the wu se olwaslwwnn. am
neosL�s la v't liremiam co�wi win not
paid lot separately. Costs ere b be vwrpoated in the as latO work,
em aee.co.en
�+
r.
"ROWID as
X"ROWID gotPI"B"
1-01
Point Concentration Surface Run-AH
^NWs: aNLMn eu.Tabn
OATS
OATS
of of
T euxaalwa,nNm
V. No
• N•'
TY um ARmw.M Cut a rm muna
D-Tb
— — — — —Limit of Drainage Basin
_
_ a rMctm
CRITERIA BASED DETENTION UOUJAAE.
PLAN DETENTION VCWME-AEA Co. R'
DETENTION H.W.L, , -SWAG
SURFACE AREA % H.W.L - 1,192 M. R
PEAK DISCHAROFA 0 . B69tnIA.
' Noe INI a Vadmll b Ure Criteria has Nm
wM this Plan alRr W
UTILITY PLAN Aa,Pr�PPR'�O�V�A�L I q
n. w:. �, ' V V !-If I bri, If
I rt
04< s +IW ligtl.i
Ice;:-:1Br udaly _._.. 99Law
He::F ev
i e�inaa wr+enlpn nw„ � a
NI 6xEn BY. _cl
eve
CHECKED B/