HomeMy WebLinkAboutSite Certifications - 06/01/1999FOUNDATION Consulting
ENGINEERING II Engineers, Inc.
1
June 1, 1999
Commission No.: 2667-03-01-02
Mr. Adam Springer \ 1
c/o Cottier Construction
350 Linden Street
Fort Collins, Colorado 80524
RE: Springer Plaza, Fort Collins, Colorado
Dear Mr. Springer:
We have visually observed the as -built grades at the above -referenced location. These observations
were initially performed on April 13, 1999. We have also compared actual elevations provided to
us by Intermill Land Surveying (Project #P-98-4192) with the proposed elevations shown on
Messner Engineering's grading plan (Job No. GRD-228-96). Additional post construction elevations
were surveyed by our office May 22"d, 1999 in order to generate cross sections of the detention
ponds which we could use to calculate their as -built volumes.
These additional elevations indicate that the west overflow point of detention pond "A" is actually
at an elevation of 34.89 in lieu of the 35.02 as shown on Messner Engineering's grading plan. Our
calculations indicate that detention pond "A" has an as -built volume of pr imately 3288 cubic
feet and detention pond "B" has an as -built volume of approximate)(eq
3040 ubic feet. Thus, the
estimated as -built total volume is approximately 6328 cubic feet. The 'red overall volume per
the grading plan is 8170 cubic feet.
We recommend the addition of two (2) four inch speed bumps to be located at the west and east
entrance/overflow points of detention pond "A". The net effect of the higher overflow point is an
increase in capacity of detention pond "A". We estimate the capacity of detention pond "A" with
the speed bumps to be approximately 5362 cubic feet. Thus, the total capacity of both ponds would
be approximately 8402 cubic feet which exceeds that which was required. It is our opinion that the
znu+umirte
as -built condition, 5�lti�cpeption of the above mentioned modification, is in conformance with
the approved$tdagl,1'otttave any questions, please feel free to call.
p tfully'd0� 6� oa
x .J•4 ^O� oµd
0
vv. -�Y/� • a ��`
FOUNDATI01�7%h,NG
JAC/jle
CONSULTING ENGINEERS, LTD.
5110 Granite Street, Suite D -Loveland, Colorado 80538 •(970) 663-0138 *Fax (970) 663-1660
500 Kimbark Street, Suite 101 -Longmont, Colorado 80501 •(303) 702-0661 *Fax (303) 774-8413
COMER CONSTRUCTION, INC.
P.O. BOX 1051
FORT COLLINS, COLORADO 80522
(970) 221-4621
-
FAX (970) 221.4656
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DATE JOB NO.
ATTENTION - -
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WE ARE SENDING YO Attache ❑ Under separate cover via the following items:
❑ Shop drawings ❑ Prints ❑ Plans ❑ Samples ❑ Specifications
❑ ❑ Change order
COPIES
DATE
NO.
- DESCRIPTION
(p - • 9c,
. 5
THESE ARE TRANSMITTED as checked below:
❑ For approval ❑ Approved as submitted
❑ For your use ❑ Approved as noted
�s requested ❑ Returned for corrections
❑ For review and comment ❑
19
REMARKS
w%c L Ga 1-i- jo
i
❑ Resubmit copies for approval
❑ Submit copies for distribution
❑ Return corrected prints
❑ PRINTS RETURNED AFTER LOAN TO US
/�;tcU
COPY TO
SIGNED:
If enclosures are not as noted, kindly notify us at once.
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FOUNDATION
ENGINEERING
April 14, 1999
Mr. Adam Springer
4500 Vista Drive
Fort Collins, Colorado 80526
Consulting
Engineers, Inc.
RE: Springer Plaza, Fort Collins, Colorado .
Dear Mr. Springer:
We have visually observed the as -built grades at the above -referenced location. These observations
were performed on April 13, 1999. We have also compared actual elevations provided to us by
Intermill Land Surveying (Project #P-98-4192) with the proposed elevations shown on Messner
Engineering's grading plan (Job No. GRD-228-96).
It is our opinion that the as -built conditions are in conformance with the approved grading plan. If
you have any questions, please feel free to call.
Res ��tf�u�ll/yam,
W��vv-s
James A. Cherry, P.E'
FOUNDATION ENG
JAC/jle
°
1 ° ��•�n
< rJ
0. 055
I! ati
ENGINEERS, LTD.
5110 Granite Street, Suite D -Loveland, Colorado 80538 •(970) 663-0138 -Fax (970) 663-1660
500 Kimbark Street, Suite 101 -Longmont, Colorado 80501 •(303) 702-0661 •Fax (303) 774-8413
DETENTION VOLUME PROVIDED
1 7/20/981 1
1
1 Instructions: Input contour elevation and the surface area that contour encompasses (A).
The spreadsheet calculates volume provided by: V=(1/3)d(A+B+SQRT(A*B))
POND #
�CONTOUR
SURFACE
SURFACE
DEPTH BETWEEN INCREMENTALI
CUMULATIVE
CUMULATIVE
�ELEVATIONJ
AREA (A)
AREA (B)
CONTOURS
VOLUME
VOLUME
VOLUME
(ft)
ft^2)
(ft^2)
(ft)
(ft^3)
(ft^3)
(acre-ft)
INVERT
32.50
0
0.00
33.00
1600
0.00
0.50
266.67
266.67
0.01
33.50
3368
1600.00
0.50
1214.90
1481.56
0.03
34.00
4592
3368.00
0.50
1982.11
3463.67
0.08
0
0.00
F 0.00
0.00
0.00
0.00
0
0.00
0.00
0.00
0.00
0.00
0
0.00
0.00
0.00
0.00
0.00
0
0.00
0.00
0.00
0.00
0.00
0
0.00
0.00
0.00
0.00
0.00
0- -'
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00 IVOLUME
PROVIDE[
3463.67 1
ft' 1
0.08 lac-ft
MAKEN 1r,
-p ot-,m . A
DETENTION VOLUME PROVIDED 1 7/20/981 1
1
Instructions: Input contour elevation and the surface area that contour encompasses (A).
The spreadsheet calculates volume provided by: V=(1/3)d(A+B+SQRT(A'B))
POND #
CONTOUR
SURFACE
SURFACE
DEPTH BETWEEN INCREMENTALICUMULATIVE,CUMULATIVE
ELEVATION
AREA(A)
AREA
CONTOURS
VOLUME
VOLUME
VOLUME
(ft)
(ft^2)
(ft^2)
(ft)
(ft^3)
(ft^3)
(acre-ft)
INVERT
33.50
0
0.00
34.00
980
0.00
0.50
163.33
163.33
0.00
34.50
4544
980.00
0.50
1272.37
1435.71
0.03
35.00
7452
4544.00
0.50
2969.18
4404.89
0.10
0
0.00
0.00
0.00
0.00
0.00
0
0.00
0.00
0.00
0.00
0.00
0
0.00
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0
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0
0.00 T
0.00
0.00
0.00
0.00.
1 0.00
1 0.00
0.00
0.00
0.00
0.00
IVOLUME PROVIDES
4404.89
W
0.10
ac-ft
COMER CONSTRUCTION, INC.
P.O. BOX 1051
FORT COLLINS, COLORADO 80522
(970) 221-4621
FAX (970) 221-4656
J_� TO _ _-��_ �_ _--C� _CJl _. .... ............................................_
� �()p r,J LA,T elr'
WE ARE SENDING YOU XAttached ❑ Under separate cover via _
❑ Shop drawings ❑ PrintsPlans
❑ Copy of letter ❑ Change order ❑
dG�4f�G3 OCR 4 ° I�I�G��44LQ�
DATE JOB NO.
-a 6 - /er �a2
ATTEII//ff�-�`��IINAO,
RE: CC J
�-
Qr�a Ce(Itca
the following items:
❑ Samples ❑ Specifications
COPIES
DATE
NO.
DESCRIPTION
qp
(del " nk CPIC4 rD/l P err �ZjU Q r�KS��%
IX
�ynte ��a�1.5 uirJ�ii ��eUQti 075 ��dw��.L►t.{P/'vNrv�r/
(j-e1-eC./C4A,
THESE ARE TRANSMITTED as checked below:
For approval ❑ Approved as submitted ❑ Resubmit copies for approval
❑ For your use ❑ Approved as noted ❑ Submit copies for distribution
❑ As requested ❑ Returned for corrections ❑ Return corrected prints
❑ For review and comment ❑
❑ FOR BIDS DUE 19 ❑ PRINTS RETURNED AFTER LOAN TO US
- REMARKS
COPY TO SIGNED:
_ If enclosures are not as noted, kindly notify us at once.
FOUNDATION
ENGINEERING
April 14, 1999
Mr. Adam Springer
4500 Vista Drive
Fort Collins, Colorado 80526
Consulting
Engineers, Inc.
RE: Springer Plaza, Fort Collins, Colorado
Dear Mr. Springer:
We have visually observed the as -built grades at the above -referenced location. These observations
were performed on April 13, 1999. We have also compared actual elevations provided to us by
Intermill Land Surveying (Project #P-98-4192) with the proposed elevations shown on Messner
Engineering's grading plan (Job No. GRD-228-96).
It is our opinion that the as-built.conditions are in conformance with the approved grading plan. If
you have any questions, please feel -free to call.l
Respe tfully,
James A. Cherry, P
FOUNDATION ET
JAC/j le
ENGINEERS, LTD.
5110 Granite Street, Suite D -Loveland, Colorado 80538 •(970) 663-0138 -Fax (970) 663-1660
500 Kimbark Street, Suite 101 -Longmont, Colorado 80501 •(303) 702-0661 *Fax (303) 774-8413
JUST THE FAX
COMER CONSTRUCTION, INC.
350 Linden Street
P.O. Box 1051
Ft. Collins, CO 80522
Phone Number 970-221-4621
fax Number 970-221-4656
SEND TO;
Compan Name S/`��
From:
Date: .
Q urgent Reply requested Please Comment Please Review For your Information
Total pages, including cover sheet. �.
COMMENTS:
DRAINAGE INVESTIGATION
MAKEN II
Lot 3 of the Gateway at Harmony Road P.U.D.
3rd Filing
CITY OF FORT COLLINS, LARIMER COUNTY, COLORADO
Prepared for
Springer Investment Group
4500 Vista Drive
Fort Collins, Colorado 80526
September 1998
Project No. GRD - 286 - 98
M 015M E Emheertxa Inc.
150 E. 29th Street, #238 Loveland, Colorado 80538 Tt-lephone: (970) 663 - 2221
September 11, 1998
Project No. GRD - 286 - 98
Mr. Basil Y. Hamdan
Stormwater Utility
235 Mathews
R O. Box 580
Fort Collins, Colorado 80522-0580
Dear Mr. Hamdan,
L,
The enclosed report represents the results of the drainage investigation for the
proposed "Maken II" to be located on Lot 3 of "The Gateway At Harmony Road P.U.D.
Third Filing" in the City of Fort Collins, Larimer County, Colorado.
This investigation was based upon the proposed site development plan; 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.
If you should have any questions, please feel free to contact this office.
Submitted,
igineering, Inc.
Dennis R. Messner, President
DRM/mkm
Enclosures
cc: Springer Investment Group
Civil and Environmental Engineering Consultants
150 E. 29th Street, Suite 238 Loveland, Colorado 80538 Telephone: (970) 663-2221
Letter of Transmittal
Table of Contents
Scope
Site Description
"Historic" Conditions
Proposed Development
Erosion Control Measures
Conclusions and Recommendations
References
Drainage Summary
Erosion Control Cost Estimate letter
i
ii
1
1
1
2
2
3
4
EXHIBITS
Vicinity Map
"Historic" Conditions Exhibit
Proposed Conditions Exhibit
Calculations
ii
The following report represents the results of a drainage investigation for a proposed
commercial development to be located in the Southeast Quarter of Section 35, Township
7 North, flange 69 West of the 6th P.M.in the City of Fort Collins, Larimer County,
Colorado. The investigation was performed for the project developer, Maken
Partnership. 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 the 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; proposed building 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.
N
The site is considered to be somewhat rectangular and contains approximately 0.853
acres. The site's East-West dimension is approximately 262 feet, its North -South
dimension at the West boundary is approximately 160 feet and its North -South
dimension at the East boundary is approximately 115 feet. The site abuts the westerly
right -of- way of College Avenue. The site is located in the McCLELLANDS/MAIL
CREEK DRAINAGE BASIN.
The site is vacant and is surrounded by streets or existing development. The ground
surface has been roughly graded and is bare of vegetation. The site slopes are
considered to be moderate and range from 1 % to 3 %. The "historic" direction that the
site slopes is from North. to South toward Mail Creek. The major portion of the site
slopes from Northwest to Southeast and drains toward College Avenue. The run-off
generated in the area to the West of College Avenue is directed into a 42 inch diameter
storm drain that is situated along the westerly side of College Avenue. The storm drain
discharges into Mail Creek.
The area to the South of the site is a McDonald's restaurant. The site improvements for
the restaurant have been designed to direct the surface run-off to a detention pond
located at the East side of the site. No run-off from the South contributes to the drainage
on site. The area to the West is an internal access drive and parking lot. The site
improvements for the parking lot have been designed to direct the surface run-off to a
detention pond located at the North side of the site. A small amount of run-off from the
West contributes to the drainage on site. The area to the North is a Jiffy Lube and car
wash. The site improvements for the Jiffy Lube and car wash have been designed to
direct the surface run-off to detention ponds located at the East side of the site. A small
amount of run-off from the North contributes to the drainage on site. The area to the
East is College. Avenue. The street improvements for College Avenue are much lower
than the site and therefore does not contribute to the drainage on site.
1
PROPOSED DEVELOPMENT
The proposed development is to consist of an 11,685 square foot commercial structure to
be located in the northwest corner of the site. The proposed access drives and parking
are to be situated along the West, South and East sides of the structure.
As previously stated the run-off from the site flows onto College Avenue. There are no
other drainage facilities available to accept run-off from the site.
The current City policies require that the difference between the historic rate of run-off
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. The drainage plan and report for The Gateway at
Harmony Road P.U.D. has established the detention requirement for the site at the
difference between the allowed run-off rate, 0.5 c.f.s./acre; and the 100 Year storm
event. The proposed detention facilities will outfall to the 42 inch storm drain located
along College Avenue. The on -site detention is to be provided at two separate areas
within the parking lots on the site.
The City's policies normally require that the adjacent street flows be incorporated with
the onsite detention requirements. This policy applies most efficiently when the street
construction and onsite detention are performed concurrently. In this instance, it is
not physically feasible to combine the two flows since the flow generated on the streets
can not be intercepted and directed into an on -site detention facility and then routed
back into the curb and gutter. The area within the westerly half of the College Avenue
right-of-way has been considered as tributary to. the detention facilities for sizing
purposes.
The existing detention facilities located to the West and North of the site outfall through
a storm drain pipe that is located on the proposed Maken II -P.U.D. site. The existing
pipe is situated under a portion of the proposed structure. Therefore the storm drain
pipe will need to be relocated in order to avoid conflict with the structure.
The established physical features surrounding the site greatly limit the ability to make
vertical elevation changes that would allow for a single detention basin.to be provided.
This also poses the problem that in order to maximize the detention volume to be placed
on the site, the depth of detained run-off exceeds the desired depth of one foot.
Therefore, a variance to the City's standards is requested.
EROSION CONTROL MEASURES
Erosion control considerations are based upon the short term activities that occur
during construction and the long term measures that are to be placed for the life of the
facility. The long term measures are the proposed methods and materials to be used to
provide surface treatments for the driveways, parking areas, walkways and the
landscape materials and plantings in the open areas that will provide a combination of
ground covers to deter erosion.
P6
The anticipated construction schedule should have the site grading completed, within
one (1) week after' commencing construction. The schedule for construction activities is
anticipated to be: Week 1, install erosion control and perform site grading; Weeks 2 & 3,
construct drainage related facilitiesand install additional erosion control measures;
Weeks 3 & 4, install building foundation and water and sewer service lines; Weeks 5
through 18, construct structure; Weeks 9 & 10, construct curb, gutter and sidewalks;
Week 10, place pavement; and Weeks 17 & 18, install landscaping.
The recommended short term erosion control methods to be incorporated with the
construction activities consist of the following: prior to commencing construction a
"Silt Fence" is to be placed along the eastern boundary of the site in order to control and
contain mud and debris onsite; upon completion of grading operations and at the time
that the drainage inlets are installed a "Straw Bale Filter" is to be placed at each inlet;
and tracked mud to be cleaned up as required.
Wind erosion measures are to consist of water application and roughening of exposed
surfaces.,
CONCLUSIONS AND RECOMMENDATIONS
1. The proposed development will retain the "historic" drainage patterns.
2. The site is located in the McCLELLANDS/MAIL CREEK DRAINAGE BASIN.
The site is not located within a defined floodway or flood plain.
3. All development is to be performed in accordance with City of Fort Collins
criteria. A variance to the City's policies is requested from detention of
adjacent street flows due to physical impracticality.
4. Onsite detention of storm water is required by the City of Fort Collins. The
volume of run-off to be detained is estimated to be 8,160 cu. ft. The detention
volume has been determined based upon the calculated volume of run-off
generated by a 100 Year Storm. The site and the adjacent drive at the West side of
the site have been considered as the tributary area to determine the volume of the
detention basins. The calculated volume generated from the tributary area is to
be released at a controlled rate determined by the sum of the Master Plan rate of
run-off, 0.5 c.f.s./acre from the site plus the rate of run-off for the drive to the
West of the site. The calculated release rate is 0.53 c1s.
5. A variance is requested from the City's standard regarding the depth of detained
storm water within a parking lot. In order to provide the maximum on -site
detention facilities will require ponding to a maximum depth of one and one half
(1- 1/2) foot.
A variance is requested to allow for the discharge of storm water from College
Avenue and the adjacent right-of-way without detention. This area indicated as
Area'C' is below the site and can not drain onto the site.
3
6. The City of Fort Collins Standards for temporary erosion control measures
are to be incorporated with the construction activities. Specifically, the
following are to be incorporated in the site construction activities:
a. A "Silt Fence" is to' be placed along the easterly border of the site:
b. "Straw Bale Filters" are to be placed at each inlet.
C. Water application is to be made to prevent dust during the site
development phase of the project.
d. Roughening of the exposed earth surfaces shall take place during the
site development phase of the project.
1. City of Fort Collins, STORM DRAINAGE DESIGN CRITERIA AND
CONSTRUCTION STANDARDS, May 1984 with subsequent revisions and
additions.
2. Final Drainage Report for The Gateway at Harmony Road P.U.D., prepared by
Stewart and Associates, Inc., Fort Collins, Colorado, May 1, 1989.
3. Drainage and Erosion Control Report for The Gateway at Harmony Road P.U.D.
Third Filing, prepared by WESTEC, Fort Collins, Colorado, July 19, 1995.
4. Drainage and Erosion Control Report for Taco Cabana P.U.D. Third Filing,
prepared by WESTEC, Fort Collins, Colorado, July 19, 1995.
4
STORM WATER DETENTION SUMMARY
SITE DRAINS TO "McCLELLANDS / MAIL CREEK" DRAINAGE BASIN
GROSS SITE AREA (includes 1/2 of College Ave.) = 44,809 Sq. Ft. = 1.03 Ac. t
NET SITE AREA = 37,134 Sq.Ft: = 0.85 Ac. f
HISTORIC "C" = 0.20
DEVELOPED "C" = 0.85
HISTORIC "Q2" = 0.54 c.f.s.
MASTER PLAN RATE OF RELEASE = 0.50 c.f.s. / acre
PEAK DISCHARGE FROM DETENTION, Q = 0.53 c.f.s.
BASIN "A" - CRITERIA BASED DETENTION VOLUME = 4,944 Cu.Ft. t
BASIN "B" - CRITERIA BASED DETENTION VOLUME = 3,216 Cu.Ft. ±
BASIN `A" -PLAN DETENTION VOLUME = 4,840 Cu.Ft.
BASIN "B" - PLAN DETENTION VOLUME = 3,256 Cu.Ft.
BASIN "A" - MAXIMUM DEPTH OF DETAINED WATER = 1.5 Ft. 0 High Water
Elevation 5034.00
BASIN "B" - MAXIMUM DEPTH OF DETAINED WATER = 1.5 Ft. ® High Water
Elevation 5034.00
September 11, 1998
Project No. GRD - 286 - 98
Mr. Basil Hamdan
Stormwater Utility
City of Fort Collins
235 Mathews
R O. Box 580
Fort Collins, Colorado
80522 - 0580
Re: Maken II - P.U.D., Fort Collins, Colorado
Dear Mr. Hamdan,
The estimated cost for erosion control devices for the subject site has been estimated to
be:
1. - Silt Fence
2. Straw Bale Filter
19011 @ $2.5b/ft. =
2 Each ® $75.00/Ea.
Total
Cost ® 150% = 1.5 x $625.00
$475.00
$937.50
The cost to re -seed the 37,157 square foot site at $0.0298/sq.ft. = $1,107.28
150% of the re -seeding cost = 1.5 x $1,107.28 = $1,660.92
Therefore, the subject project's estimated erosion control security amountis
determined to be $1,660.92. This amount is to be included as surety for the erosion
control guarantee along with any other surety requirements that may be a part of the
City's "Developer's Agreement" requirements.
If you should have any questions or desire additional information, please feel free to
contact this office.
y Submitted,
Engineering. Inc.
Dennis R. Messner, President
cc: Springer Investment Group
Civil and Environmental Engineering Consultants
150 E. 29th Street,.Suite 238 Loveland, Colorado 80538 Telephone: (970) 663-2221
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MAKEN II P. U. D.
Property Description: Lot 3 of The Gateway At Harmony Road
P. U. D. Third Filing, Fort Collins, Colorado
-I
7C$YAvVL
DRAINAGE INVESTIGATION CALCULATIONS
Client:
SPRINGER INVESTMENT GROUP
Project No:
GRD-286-98
Project
MAKEN lI P.U.D.
Date:
5/19/98
Location:
Lot 3 Gateway P Harmony Road P.U.D., Fort Collins, CO
By:
D.R.M.
This investigation is being performed to determine the requited detention volume, discharge rates,
and structure sizing for the subject project site.
The site is located in the "McClellands / Mail Creek" Drainage Basin.
RATIONAL METHOD Runoff Coefficients, "C" RATIONAL METHOD
City of Fort Collins S.D.D.C.&C.S. (fable 3-3) Frequency Adjustment Factors
Land Use Description
"C'
Building/Roofs
0.95
Drives and Walks
0.95
Gravel Surfaced
0.50
Undeveloped Areas
0.20
Grassed Landscaped Areas
0,15
EXISTING CONDITIONS:
Storm Return
Period ears
Freq. Factor
"Cf
2
1.00
5
1.00
10
1 1.00
lOD
1.25
Offsite & On -site Area Draining to S. College Avenue Offsite Basin 91 + Onsite
Basins "A", "B", "C" & "D"
Building/Roof
Drives and Walks
Gravel Surfaced Landscape
Undeveloped Open Areas
Area=
0
Sq.Ft.
Area=
7,040
Sq.Ft.
Aim =
0
Sq.Ft.
Area=
35,374
Sq.Ft.
IandscapedAmas Area= 1,070 Sq.Ft.
TOTAL SITE AREA Area = 43,484 Sq.Ft. = 1.00 Acres
Avg. C = [(0.95 x 0)+(0.95 x 7,040)+(0.50 x 0)+(0.20 x 35,374)+(0.15 x 1,070)] + 43,484
Avg. "C" = 0.32
Time of Concentration Overland: Tom 1.87(1.1 - CCf ) 4D + SN/3
Distance, D = 160 Ft.
Elev. Diff. = 5037. 5033 = 4 Ft.
Slope, S = Elev. diff. / Dist. = 4 /.160 = 0.025 Ft. / Ft.
Page 1 of 9
DRAINAGE INVESTIGATION CALCULATIONS
Client:
SPRINGER INVESTMENT GROUP
Project No:
GRD-286-98
Project:
MAKEN 11 P.U.D.
Date:
5119M
Location:
Lot 3 Gateway Harmony Road P.U.D., Fort Collins. CO_
By:
D.R.M.
EXISTING CONDITIONS: Offsite & On -site Area Draining to S. College Avenue -
Offsite Basin #1 + Onsite Basins "A", "B", "C" & "D" (continued)
To = 1.87(1.1 - CCf ) JD + SAl/3 - 1.87 (1.1 - (0.32 x 1.00)) 4160 / 2.SA1/3 = 13.60 Min.
Time of Concentration Channeliaed:
Distance, D ® 150 Ft.
Elev. Diff. = 5033 - 5031.5 = 1.5 Ft.
Slope, S = Elev. diff. / Dist. = 1.5 / 150 = 0.01 Ft. / Ft.
From Figure 3 - 2. Velocity across "Nearly Bare Ground" @ 1.0 % = 1 Ft. / Sec.
Time Channeli2ed, Tch = Dist. / ( Vel. x 60) = 150 / ( 1 x-60) = 2.5 Min.
Time of Concentration, Tc = To + Tch = 13.6 + 2.5 = 16.1 Min.
USE tc = 15 Minutes
Rainfall Intensities, @ Tc = 15 minute
I 2 = 2.10 in. / hr. I 100 = 6.00 in. / hr.
Q=CiACf Q 2 = 0.32 x 2.10 x 1.00x 1.00= 0.67 c,f.s.
Q.100 = 0.32 x 6.00 x 1.00 x 1.25 = 2.40 c.f.s.
PROPOSED CONDITIONS:
The rate of release from detention has been established by the original "Gateway at Harmony Road P.U.D."
Therefore, no calculations have been made to determine the run-off volumes based upon the calculations for the
existing conditions.
The original "Gateway at Harmony Road P. U. D." report has determined the detention
release rate to be 0.5 c.f.s. / acre. (Refer to the FINAL DRAINAGE REPORT, THE GATEWAY
AT HARMONY ROAD P.U.D., May 1, 1989, prepared by Stewart & Associates, Inc.)
Area Draining to Detention in South Parking ' Lot Offsite Basin #1 + Onsite Basin 'A'
Budding/Roof Area 5,720 Sq.Ft,
Drives and Walks
Gravel Surfaced Landscape
Undeveloped Open Areas
Landscaped Auras
TOTAL AREA
Area=-
'20,423
Sq.Ft.
Area
0
Sq.Ft.
Arm =
0
Sq.Ft.
Arm =
1,459
Sq.Ft.
Area=
27,602
Sq.Ft.
= 0.63 Acres
Page 2 of 9
0
DRAINAGE INVESTIGATION CALCULATIONS
Client:
SPRINGER INVESTMENT GROUP
Project No:
GRD-286-98
Project:
MAKEN II P.U.D.
Date:
5/19198
Location:
Lot 3, Gateway R Harmony Road P.U:D., Fort Collins, CO
By:
D.R.M_
PROPOSED CONDITIONS: Area Draining to Detention in South Parking Lot -
ORsite Basin #1 + Onsite Basin 'A' (continued)
Avg, C = [(0.95 x 5,720)+(0.95 x 20,423)+(0.50 x 0)+(0.20 x 0)+(0.15 x 1,459)j + 27.602
Avg, "C = 0.91
DETENTION VOLUME CALCULATION FOR PROPOSED SITE CONDITIONS
QRelease = 0.5 c.Wacre per original Gateway at Harmony Road P.U.D.
. QRelease = 0.5 c.f.s./acre x 0.63 ac. = 0.32 c_f.s.
CCf = 0.91 x 1.25 = 1.11 > 1.00 Therefore, USE CCf = 1.00
At Q100 Proposed = CIACf = 1.00 x I x 0.63 = 0.63 x I (in./hr.)
Time
min.
Rainfall Int., I
in./hr.
Q100 Prop.
c.f.s.l
Vol. @ Q100
cuff[.
Q Rel. @ 2 Yr.
c.f.s.)
Vol. Rel.
(cu.ft.)
Vol. Diff,
(cu.R
10
7.15
4.50
2 700
0.32
192
2,508
15
6.00
3.78
3 402
0.32
288
3,114
20
5.15
3.24
3 888
0.32
384
3 504
25
4.55
2.87
4,305
. 0.32
480
3,825
30
4.10
2.58
4,644
0.32
576
4,068
40
3.45
2.17
5,208
0.32
768
4,440
50
2.95
1.86
5.580
0.32
960
4,620
60
2.65
1.67
6 012 ZILZZ-0.32
1 152
4 860
70
2.35•
1.48
6 216
0.32
1 344
4.872
80
2.15
1.35
6480
0.32
1536
4 944
90
1.95
1.23
6 642
0.32
1,728
1 4,914
100
1.75
1.10 1
6,600 1
0.32
1,920
4.680
110
1.60
1.01 1
6,666 1
0.32
2 112
4,554
120
1.45
0.91 1
6,552 1
0.32
2,304
4.248
Therefore, a minimum of 4,944 cu, ft. of Detention Storage Volume is desired for Basin 'A'.
9
Page 3 of 9
DRAINAGE INVESTIGATION CALCULATIONS
Client:
SPRINGER INVESTMENT GROUP
Project No:
GRD-286.98
Project:
MAKEN H P.U.D.
Date:
5/19/98
Location:
Lot 3 Gateway @ Harmony Road P.U.D.. Fort Collins. CO
By:
D.R.M.
PROPOSED CONDITIONS: Area Draining to Detention in South Parking Lot -
Offs1te Basin #1 + Onsite Basin 'A' (continued)
A• 1,1 T_
✓l�l y,"..0 ,�
Elevation
lam/
Area
(Sq. Ft
Avg, Area
(Sq. Ft.
Elev, Diff.
t.
Volume
Cu. Ft.
E Volume
Ci. Ft.)
Outlet
503350
12
281
0.25
70
70
5033.75
550
1.263
0.25
316
386
5034.00
1975
2,575
0.25
644
1030
5034,25
3175
3,798
0.25
947
1977
5034.50
4,400
5.100
1 0.25
1,275
1 3,252
5034.75
5,800
6,550
0.25
I637.5
4,890
5035
7,300
4,890 - 4,944, Therefore Volume @ Elev. 5034.00 OK
Area Draining to Detention in East Parking Lot Offsite Basin #2 + Onsite Basin 'B' +
Onsite Basin 'C' (College Ave.) + Onsite Basin 'D'
Building/Roof
Drives and Walla
Gravel Surfaced Landscape
Undeveloped Open Arms
Landscaped Arts
Area=
5.909
Sq.Ft.
Area=
13,315
Sq.Ft.
Area=
0
Sq.Ft.
Area =
0
Sq.Ft.
Area =
4,157
Sq.Ft.
(includes 1/2 of College Ave.)
(includes 1/2 of College Ave.)
TOTAL SITE AREA Area 23,381 Sq.Ft. = 0,54 Acres
Avg. C = ((0.95 x 5,909)+(0.95 x 13,315)+(0.50 x 0)+(0.20 x 0)+(0.15 x 4,157)) + 23,381
Avg. "C" = 0.81
DETENTION VOLUME CALCULATION FOR PROPOSED SITE CONDITIONS
QRelease = 0.5 c.fsiacre x 0.54 ac. = 0.27 c.f.s.
CCf = 0.81 x 1.25 = 1.18 > 1.00 Therefore, USE CCf = 1.00
At Q100 Proposed = CIACf = 1.00 x I x 0.3 = 0.54 x I (in../hr.)
Page 4 of 9
DRAINAGE INVESTIGATION CALCULATIONS
Client: SPRINGER INVESTMENT GROUP Project No: GRD-286-98
Project: MAKEN II P.U.D. Date: 5/19198
Location: ' Lot 3 Gateway @ Harmony Road P.U.D., Fort Collins, CO By: D.R.M.
PROPOSED CONDITIONS: Area Draining to Detention in East Parking Lot -
OfYsite Basin #2 + Onsite Basin 'B' + Onsite Basin 'C' + Onsite Basin 'D' (continued)
DETENTION VOLUME:
Time
min.
Rainfall Int., I
(in./hr.
QI00 Prop.
c.f s.
Vol. @ Q100
cu.ft.
Q Rel. @ 2 Yr.
c,f.s,)
Vol. Rel.
(cu.ft.)
Vol.*Diff.
(cu.ft
10
7.15
3.86
2 316
0.27
162
2,154
15
6.00
3.24
2 916
0.27
243
2 673
20
5.15
2.78
3,336
0.27
324
3,012
25
4.55
2.46
3 690
0.27
405
3,285
30
4,10
2.21
3,978
0.27
496
3,492
40
3.45
1.86
4 464
0.27
648
3,916
50
2.95
1.59
4 770
0.27
810
3 960
60
2.65
1.43
5148
0.27
972
4176
70
2.35
1.27
5.334
0.27
1,134
4,200
80
2.15
1.16
5.568
0.27
1,296
4,272
90
1 1.95
1.05
5,670
0.27
1 458
4.212
100
1 1.75
0.95
5 700
1 0.27
1 1,620
4 080
110
1.60
0.86
5 67b
0,27
1,782
3,894
120
1 1.45
0.78
5,616
1 0.27
1 1,944
3 672
Therefore, a minimum of 4,272 cu. ft. of Detention Storage Volume is desired for Basin'B' with College
Avenue considered as contributing.
Consider Detention Volume required without College Avenue contributing:
Building/Roof Arm = 5,909 Sq.Ft.
Drives and walks Area = 8,962 Sq.Ft. (w/o College Ave.)
Gravel Surfaced Landscape Area= 0 Sq.Ft.
Undeveloped Open Arras Area = 0 Sq.Ft.
Landscaped Areas Area = 2.814 Sq.Ft. (w/o College Ave.)
TOTAL SITE AREA Area = 17.685 Sq.Ft. = 0.41 Acres
Avg. C = [(0.95 x 5,909)+(0.95 x 8,962)+(0.50 x 0)+(0.20 x 0)+(0.15 x 2,814)) + 17,685
Avg. "C" = 0.82
DETENTION VOLUME CALCULATION FOR PROPOSED SITE CONDITIONS
QRelease = 0.5 c.f.s./acre x 0.41 ac. = 0.21 c.f.s.
CCf = 0.82 x 1.25 = 1.03 > 1.00 Therefore, USE CCf = 1.00
At Q100 Proposed = CIACf = 1.00 x I x 0.3 = - 0,41 x I (in./hr.)
Page 5 of 9
DRAINAGE INVESTIGATION CALCULATIONS
Client:
SPRINGER INVESTMENT GROUP
Project No:
. GRD-286-98
Project:
MAKEN II P.U_D.
Date:
5/19l98
Location:
Lot 3 Gateway @ Harmony Road P.U.D.. Fort Collins, CO
By:
D.R.M.
PROPOSED . CONDITIONS: Area Draining to Detention in East Parking Lot
Offsite Basin #2 + Onsite Basin 'B' + Onsite Basin 'C' + Onsite Basin 'D' (continued)
DETENTION VOLUME: Consider Detention Volume required without College Avenue contributing:
Time
min.
Rainfall Inc., I
in./hr.
Q100 Prop.
c.f.s.
Vol. @ QlW
(cu.ft.)
Q Rel. @ 2 Yr.
(c.f.s.)
Vol. Rel.
(tuft
Vol. Diff.
cu.ft.
10
7.15
2.93
1758
0.21
126
1,632
15
6.00
2.46
2,214
0.21
189
2025
20
5.15
2.11
2 532
0.21
252
2,280
25
4.55
1.87
2,805
0.21
315
2,490
30
4.10
1.68
3,024 1
0:21
378
2,646
40
3.45
1.41
3 384
0.21
504
2,880
50
2.95
1.21
3 630
0.21
630
3,000
60
2.65
1.09
3 924
0.21
756
3 168
70
2.35
0.96
4 032
0.21
882
3 150
80
2,15
0.88
4224
0.21
1,008
3,216
90
1 1.95
1 0.80
4.320
0.21
1,134
1 3 186
100
1.75
1 0.72
4 320
0.21
1,260
3 060
110
1.60
1 0.66
4,356
1 0.21
1,386
2 970
120
1.45
1 0.59
4,248
1 0.21
1.512
1 2,736
Therefore, a minimum of 3,216 cu. ft. of Detention Storage Volume is desired for Basin 'B' without College
Avenue considered as contributing.
Since it is not physically feasible to route the run-off from College Avenue onto the site' and the additional
volume would place an undue liability due to the depth required to generate the desired volume, a waiver to the
requirement of detaining the adjacent street is to be made. Note that the street flows art directed to existing inlets
that discharge to the existing 42" storm drain at the eastern side of the site. Therefore, the storm drain will retain
the existing flows.
31256 > 3,216 Therefore, Volume at Elev. 5034.00 OK
Page 6 of 9
DRAINAGE INVESTIGATION CALCULATIONS
Client:
SPRINGER INVESTMENT GROUP
Project No:
GRD-286.98
Project:
MAKEN II P.U.D.
Date:
5/19/98
Location:
Lot 3 Gateway 0 Harmony Road P.U.D.. Fort Collins, CO
By:
D.R.M.
PROPOSED CONDITIONS:
Determine Orifice Opening Area for Basin 'A':
Orifice Equation: Q - CA J2gh
h - 5034.00 - 5031.50 =
2.50
ft.
Q Release =
.0.32 c.f.s. C =
0.65
A = Q / (C42gh) = 0.32 / (0.65 4(2 x 32.2 x 2.50)] =
0.04
sq.ft_
With Round Opening A = rrr" 2
Radius, R = JA/a = J 0.041n =
0.11
ft.
Radius, R = ft. x 12 in./ft. =
1.32
in.
With Square Opening A = w^2
Width of Opening, W = JA = 40,04 =
0.20
ft.
Width of Opening, W = ft. x 12 in./ft. =
2.40
in.
Use 2-318" dia. Round Opening or 2-318" Square Orifice opening for outlet control device.
Determine Orifice Opening Area for Basin 'B':
Orifice Equation: Q = CA 42gh h = 5034.00 - 5031.50 = 2.50 ft.
Q Release = 0.21 c.f.s.
C = 0.65
A = Q / (CJ2gh) = 0.211 (0.65 J(2 x 32.2. x 2.50)] = 0.03 sq.ft.
With Round Opening A = nr^2 Radius, R = JA/n = J 0.03/7r = 0.10 ft.
Radius, R = ft. x 12 in./ft. = 1.20 in.
With Square Opening A = WA Width of Opening, W = JA = 40.03 = 0.17 ft.
Width of Opening, W = ft, x 12 in./ft. = 2.04 in.
Use 2.112" dia. Round Opening or 2" Square Opening for outlet control device.
Page 7 of 9
DRAINAGE INVESTIGATION CALCULATIONS
Client:
SPRINGER INVESTMENT GROUP
Project No:
GRD-286-98
Project:
MAKEN II P.U.D.
Date:
5/19198
Location:
Lot 3 Gateway (a Harmony Road P.U.D.. Fort Collins, CO
By:
D.R.M.
PROPOSED CONDITIONS:
CHECK FLOWS -FOR PROPOSED CONDITIONS:
Consider Offsite and Onsite areas concentrating at Basin 'A'
Offslte Area #1
Building/Roof
Drives and Walks
Gravel Surfaced Landscape
Undeveloped Open Areas
Landscaped Areas .
Area=
0
Sq.Ft.
Area=
6,370
Sq.Ft.
Arm =
0
Sq.Ft,
Arm =
0
Sq.Ft.
Area=
1.390
Sq.Ft.
TOTAL SITE AREA Area 7,760 Sq.Ft. _ ! 0 18 Acres
Avg. C = [(0.95 x 0)+(0.95 x 6.370)+(0.50 x 0)+(0.20 x 0)+(0.15 x 1,390)) + 7,760
Avg. "C.' _ 0.81
Time of Concentration Overland: To = 1.87(1.1 - CCf) dD + SAlr3
Distance, D = 60 Ft.
Elev. Diff. = 5038.5 - 5036.5 = 2 Ft.
Slope, S = Elev. diff. / Dist. = 4 / 60 = 3.33 %
To = 1.87(1.1 - CCf ) 4D + SAJ/3 = 1.87.(1.1 - (0.81 x 1.00)) d60 / 3.33A1/3 = 2.30 Min.
Time of Concentration Channelized:
Distance, D = 115 Ft.
Elev. Diff. = 5036.5 - 5035.5 = 1 Ft.
Slope, S = Elev, diff. / Dist = 1.0 / 115 = 0.87 %
From Figure 3 - 2. Velocity across "Shallow Gutter Flow" @ 0.9 % = 1.9 Ft. / Sec.
Time Channelized, Tch = Dist. / (Vel. x 60) = 115 / ( 1.9 x 60) = 1.01 Min.
Page 8 of 9
DRAINAGE INVESTIGATION CALCULATIONS
Client SPRINGER INVESTMENT GROUP Project No: GRD-286698
Project MAKEN II P.U.D. Date: 5/19/98
Location: Lot 3 Gateway Harmony Road P.U.D., Fort Collins, CO By: D.R.M.
PROPOSED CONDITIONS: Consider Offsite and Onsite areas concentrating at Basin 'A' - Offsite Area 'A'
(continued)
Time of Concentration across paved parkingiot. _
Distance, D = 135 Ft.
Elev. Diff. = 5034.5 - 5033.0 = 1.5 Ft.
Slope, S - Elev. diff. / Dist. = 1.5 / 135 = 1.11
From Figure 3 - 2. Velocity across "Paved Area Flow" @ 1.1 % = 2.1 Ft. / Sec.
Time Channelized, Tp = Dist / ( Vel. x 60) = 135 / ( 2.1 z 60) = 1.07 Min..
Time of Concentration, Tc = To + Tch + Tp = 2.30 + 1,01 + 1.07 = 4.38 Min:
USE tc = 5 Minutes
Rainfall Intensities, @ Tc - 5 minute
I 2 = 3.25 in. / hr..
I 100 s
9.00
in. / hr.
Q=CiACf
Q2=0.81.x3.25x0.18x1.00=
0.47
c.f.s.
Q 100 = 1.00 x 9.00 z 0.18 =
1.621
c.f.s.
Flow to be carried in gutter or valley pan
n =
0.016
Q = 1A86 ARA213 SA1/2 + n
Slope, S =
0.012
@ 2" depth in valley - pan
Area, A = _
1.53
sq. ft.
Wp =
12.33
ft,
R = A/Wp =
0.12
ft.
Q =
3,79
c.f.s.
3,79 >> 1.62 Therefore, OK
Total Flow exiting Site from piped system:
.
Q out of Basin 'A' + Qout Basin 'B' = 0.32 + 0.21 =
0.53
c.f.s.
Q from upstream detention =
0.65
c.f.s.
Check for Q = 0.32 + 0.65 = 0.97 c.f.s.
@ 12" dia. w/ S = 0.6% Q =
2.76
c.f.s.
Check for Q = 0,32 + 0.21 + 0.65 = 1.18 c.f.s.: @ 15" dia. w/ S = 2.8% Q = 10.81 c.f.s.
Page 9 of 9
A
RAINFALL PERFORMANCE STANDARD EVALUATION
PROJECT: STANDARD FORM A
MAKEN II P.U.D.
COMPLETED BY: '-Messner Enor. Assoc. D.R.M. DATE: 11_ 96
DEVELOPED
ERODIBILITY
Asb
Lsb
Ssb
Sb
PS
SUBBAgIN
ZONE
(ac)
(ft)
M
(feet)
(t)
M
Entire
Moderate
0.853
235
1.3%
77.7
Site
MAACH 1991 8.14 DESIGN CRITERIA
EFFECTIVENESS CALCULATIONS
TANDARD FORM B
PROJECT: MAKEN II P.U.D.'
DATE: 11-22-96
COMPLETED BY: MPcsner Enjr Assoc D R M
Erosion Control C-Factor P-Factor
Method Value Value Content
Bare Soil 1.00 1.00
Road/Walk 0.01 1.00
Silt Barrier 1.00 0.50
Sediment Trap 1.00 0.50
Gravel Filter 1.00 0.80
MAJOR
PS
SUB
AREA
BASIN
M
BASIN
(AC)
CALCULATIONS
ntire
77.7
0.853
O.B53
Bare Soil = 0.40 ac.
Road/Walk = 0.453 ac.
wtd. C = (1.0 x 0.40) + (0.01 x 0.453)/
0.653
=0.47
wtd. P = 0.5 x 0.5 x 0.5
= 0.13
Eff. = (1 - Pc' x 'P')) x.100
_ (1 - (0.47 x 0.13)) x 100
= 93.9
93.9V)77:7 Therefore, OK
MARCH 1991 8.15 oesIGH CRITERIA
CONSTRUCTION SEQUENCE
PROJECT: MAKFN TT n rt r STANDARD FORM C
SnQUEaCa FOR 19 97 ONLY COMPLETED BY: Messner Enar'._ D.R.M.DATE: 11_2 —96
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
RAINFALL EROSION CONTROL
STRUCTURAL:
Sediment Trap/Basin
Inlet Filters
Straw Barriers
Silt Fence Barriers
Sand Bags
Bare Sail Preparation
Contour Furrows
Terracing
Asphalt/Concrete Paving
Other
VEGETATIVE:
Permanent Seed Planting
Mulching/Sealant
Temporary Seed Planting
Sod Installation
Nettings/Mats/Blankets
Other
----------------------------
1997
Jan-1 Feb! Markpr I May! Junl JullAug ISep IOct INov IDec
1.
i
I
I
----------------••-------•--------------------•-------------�
STRUCTURES: INSTALLED BY MAINTAINED BY
VEGETATION/MULCHING CONTRACTOR
DATE SUBMITTED APPROVED BY CITY OF FORT COLLINS ON
HDI/SF-C:1989 .
Ii:Zd�'1[s7:IKsL`YL'Za]MZP111Ya
The City of Fort Collins StarmFater Wlily session
control inspector must be mUOed
at least 24 hours prior to any construction an this site.
NI r qu'red perimeter Gill fencing shall be install year to any land disturbing
octiviy (slockpilmg. stripping• grading. etc,), At other required control measures
sholl be insisted at Pe appropriate time In the mmWclion sequence tie indicated
in the approved project schedule. construction plans. and erosion control report.
Pre -disturbance vegetation shall be Protected and retained whemer Qaibe. Removal
or disturbance f existing vegetation shall be limited to the or required for
immediatecroslructi n Perform and for the shortest practical pence of time
Design
Pent
Basin Mao
Designation (=vas)
ROUond 'C'
Or
(C-W
aim
(cf.a.)
06L Veluma
(cn K)
0 ReNaae
WAL)
D.P. 01
Offend /1 0.18
0.81
0.39
1.29
N/A
N/A
D.P. /2
ORsiG /2 0.04
0.15
0.m -
D.OS
N/A
N/A
[D.P 13
OnsiG 'A' 0,48
0.95
1.09
ZL g
4,944
0.32
OP. /4
OnMts B. 0.30
0.94
071
2.15
3.2te
0.21
O.P. /5
OnaRe 'C' 0.18
U.e1
O.E
129
N/A
N/A
D.P. /8
OnsiG U. OLIO
0.5
0.13
0.45
N/A
MIA
DP
All soils gNpoxg sonny lava To kept
i odMry (shipping. o. grading.utilityripity In or di cing
along lind rising. etc.? Shsil be xReg in a . or oche condition 5y ering or trot is s.
along Iona aonGms crew mulch, project H abler por wa shall
ll rem control a j
d m n site °I w mall it ea
installed. no eo a aroes ameiae project street y vy mesa expo
wed
perm aieGrGp on ofor more than thirty land can before rise Time temporary
unless
a permanent voed control (e.g. sees UtilM, landscaping• etc) ts Installed, unless I
otherwise approved by the Slormwoter Utility. '
The property shall be watered and maintained at oil time • during construction `
activities zaas to prevent wind -caused erosion. At land disturbing octiviies 4
enter be Immedialery discontinued when fugitive duet impacts adjacent properties, m
determined by the City of Fart Collin Engineering Department.
All temporary (structural) erosion control measures shall be inspected and repaired
or reconstructed as necessary after each runoff event to assure continued
performance of their function. AI relainem sediments. pordicularly these on paved
modway surfaces, shall W removed and dip of In a Prowler and location so
as not to cause their asterisk into any dnmageway. �e
No soil stockpile shall exceed ten (10) feel In height. AI sail stockpiles shall few
protected from sediment transport by surface roughening watering,, and perimeter I _
silt fencing. My mil stockpwe remaining alter 30 do" sMll be seeded and mulched.
City Ordinance prohibits the backing, dropping, or depositing of voile or ne a any 184 Veil ry Pon
-
other motanol onto City streets by or from any vehicle. ANYmodyertanty deposited p SEE DETAIL
material shall be cleaned immeairitely by the collimator. AT LEFT
I I OFFSITE
'I BASIN /i I
Existing 8' PVC
e =r uarr Storm Drain-I(� I POINT #1
DESIGN
:feting Manhole
a. OR; 0+00 LSto and Verticdl
r4' VALLEY PAN m 5we 503 1 C & Gutter
v.8eN 5032.93t
v.8R E = 5032.93t /
Typically
Indicates
Existing 6'
Vertical
Curb
@ Cutter
FILTER FABRIC
"OD POST
_
l--
-
exxmlEo TRENCH
}
:IIV
FILTER FABRIC
ATTACH SECURELY
w000 POST TO vast
1. =Buren
ENO
nL1ERFF /�RU'OF ED fl1CNilL
PER 1
p.zs A'.R6 aLn W
iri* o
RUNG" / RUNOr
ratio.
2 MPEEm rep fEHR.M
rial FYEM. M✓T'f SERYpr
10 'A➢wOXWRIFIY
elal ME xYI ONE HOME Of PC
MIN. .
rNKsE Nw afar axlFD. AEYhID
TRENCH
mum 9WL K aFiO511ro He AN
AREA
M A 4anlwr EllIN
SCLROX VICW
ammEP�inlE
SILT FENCE DETAIL
WT
TO SCALE
.!7 Hook eRRrz
A
IIIIIIIII
smur ova SEdaa
win [ incase Res eDOLEA
A
mid
mum
rw�
ZA¢x
THE Mae.
.SSEArN
2 INSHLOCT. Real AND wA.•6 THE
%
�.
FILTERS AnneEAGI STORY EARY
Ra.lo.E xvMETn FrmX DHE xur a
THE ETFN CETH HASam ruID.
�.
SWICIE SIWO ix pa091ro
rsW1^v1FAa
e• MN
0 Ad Affix; TO A SELMn1r
AN
16TAMa
°X PUTS
OR
rtrnox A -A
SR FIR
3 S
ivnmm�o M OFr � ROME10nm
AREA INLET FILTER STRAW
BALES
NOT 70STILE
C�
STORM WATER DETENTION SUMMARY
SIDE DRAINS TO 'MCCLELLANOS / MAIL CREEK' OEUNAGE BASIN
GRUBS STE AREA (included 1/2 of Collage Ave.) -46.401 Sq.It. - 1.07 Ac.2
NET SITE AREA - 37.157 Sq.FL - 0.853 M.3
HISTORIC •C• - 020
DEVELOPED OC' - O.B5
HISTORIC •02' - 0.54 CJ.s.
CmTERm EASED MENTION VOLUME - BLISS Cu.Pt-*
PUN DETENION VOLUME - 8.170 Cu.FL
MAXIMUM DEPTH CIF MANED WATER - t.50It. MAXIMUM
PENS DISCIWRCE FROM MENTION, 0-YIISTORIC' 02 + OOFTSTE
=•1.72 c.fS 3
5Es> dots\ aRE=
Existing Landscape Tim(xn
to 12e Removed to Construct
sidewalk along Rgar of Building
� I
Existing
6.1 6.2 /- - Jiffy Lucre IIIII111
/ Building J
DESIGN 1MI
6. POINT /2 J.
5. \ OFFSITE
BASIN }'2
Proposed 'Silt Fen
5.7 / /roposed�Bur sing
F.F./ 5036.25
7
Proposed Landscaping Wall
Top of Wall = 35.25
-1F All FLOW L1,115 sxouA
All FLOW wf uuL6>s
ReiWie LreIUTm.
Ewe 50 6. Ouvr W.
Be PVC Storm . . /- lv
1+41.0
Top ¢ro-
SInv.B-
MJn/S= 502M Place Orifice Plate
In Inlet SEE DETAII
MCDONALDS BASIN aG'
H.W.
SEEM
15, 1
X011lEap-J�E-1}ht
eraara
srar[ m mnE[r
SIT
11
xk 2y LLL
-
ar
[ttlox txRu MRorx mrnox rxRu tExttx
GRATED INLET TYPE 13
Storm
•u�l•T
EXISTING CURB a GUDERHI
SECTION C-C
SECTION D-D
1N sin 6aLrs 0 esa
TO IOU
o
2, 1
n 3ft M OR 2V sea
data l2-2Y[ALL MIVSO
naaNe
wrz LY
2:r
VON N• Y• n
s leioa
ORIFICE PLATE DETAIL
u
■
^ U. x..m r nuaAD raw c
SOMEc[ FOR sine ONLY ewnnm EY: urines r.rw r w2 9-1_98
M RflE RED, ins MODI .. n O AN pemeRs Rmin s�wnmD
site
vs'ru.R'uTFe.�
Not Applicable
s:'Pstrike
Site is Less than 1 Acre
Other Retwe ronam-O
mNrru
ORkrm
1WOMEN
SM. Evvi p.
Fit F.
Has
w2°.W
ov,..aw
TZi"
Vcs..rn n,M
nnmmn
T,,Nwwr ai
pi waaakift
Heelln9•/Nam/RMxbA
aMxnea Rem ain w uRmANm w
w¢1ARIMA^MINd CWRMIR
wrt Sa9rnnD A^Rp.ID A vn v Mr lave w _
it �I Propose Londscoping Wall l
Top of all 34.25 V 1 aywe
o Proposed\lnlet A2 U
Sta. 2+ 45
Top Grate �5032.50 m
Inv.12'W= 5927.50
i Inv.15'S= 5026.373 (Match Exist.)
Place Orifice Plate Horizontally w
S N in Inlet SEE DETAIL AT RIGHT
3 , 5 xa� N
0.18 ac.
C' .3 1.2
Existing Manr1hole 0
Sto. 3+38.74 Q-I'
n ty Rim No 5031.30 UI
Inv.15eNW=5024.96 LL
Inv.42' N=5016.1t
Inv.42e 5=5016.1t 10 aD E_..i W C
_ z a lzi
O 20 60
/ Contour 2 Interval = 0.5' Zp
V) wild
R NOTE: I. top Of Curb is 0.5' Above Flow line Unless Otherwise W EllL
Noted. 1y,y Z B
2. See Soils Report Ira Pavement Thickness. H a C
k
1 ]. See MCM1itaduml Site Plan for Builmng Dimensions. rs�
I W
W
Out
- 50t3- Typically Indicates Exi ling a4
Ground Surtaca Contop U
Typically Indicates Pro osed City of Fori Collins, Colorado g a
IDlah Surface Contou UTILITY PLAN APPROVAL ZI o:
o Q.
\.ftvvv Drainage Basin Limit entifier APPROVEDyE Oir�m a QI 9 DATE: JULY 31,199E
T I'Colly Indicates Ex' ing CHECKED BY: }zs•gp. SCALE: 65 NDrED
99.11 PPavement Surface El ation N°1O' a ^O�erURT�
K DMWN: M.S.R.
or Flow Line of Gutt CHECKED BY: ,46
'7-1/L-CHKD. 0 R M t y
Typically Indicates Pr osed
Pavement Surtaca El alion CHECKED BY: Project No.
+ or Flow Line of Cult ` R" °f"^ GRD-228-96
CHECKED BY: SHEEP
Tycat
Dcally e
9 Indicates Or a CC
�� Floirection CHECKED BY: 3 of 6