HomeMy WebLinkAboutLAKEVIEW ON THE RISE, AFFORDABLE HOUSING - PDP - PDP170014 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTPreliminary Drainage and Erosion Control Report
for
Lakeview on the Rise
Fort Collins, Colorado
April 26, 2017
April 26, 2017
Mr. Wes Lamarque
City of Fort Collins
Water Utilities--Storm water
700 Wood Street
Fort Collins, Colorado 80521
RE: Preliminary Drainage and Erosion Control Report Lakeview on the Rise
Dear Wes:
We are pleased to submit to you, for your review and approval, this Preliminary Drainage and
Erosion Control Report for Lakeview on the Rise. All computations within this report have been
completed in compliance with the City of Fort Collins Storm Drainage Design Criteria.
We appreciate your time and consideration in reviewing this submittal. Please call if you have any
questions.
Respectfully,
Aspen Engineering
John Gooch, P.E.
Principal
TABLE OF CONTENTS
DESCRIPTION PAGE
I. GENERAL LOCATION AND DESCRIPTION 5
A. LOCATION 5
B. DESCRIPTION OF PROPERTY 5
II. DRAINAGE BASINS 6
A. MAJOR BASIN DESCRIPTION 6
B. EXISTING SUB-BASIN DESCRIPTION 6
C. PROPOSED SUB-BASIN DESCRIPTION 6
III. DRAINAGE DESIGN CRITERIA 7
A. REGULATIONS 7
B. DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS 8
C. HYDROLOGIC CRITERIA 8
D. HYDRAULIC CRITERIA 8
E. VARIANCES 8
IV. DRAINAGE FACILITY DESIGN 8
A. GENERAL CONCEPT 8
B. SPECIFIC DETAILS 9
C. DETENTION POND 15
D. STREET CAPACITIES 16
V. STORM WATER QUALITY 16
A. GENERAL CONCEPT & SPECIFIC DETAILS 16
VI. EROSION CONTROL 16
A. GENERAL CONCEPT 16
VII. CONCLUSIONS 17
A. COMPLIANCE WITH STANDARDS & STORMWATER 17
OPERATIONS/ MAINTENANCE PROCEDURE
B. DRAINAGE CONCEPT 18
C. STORM WATER QUALITY 18
D. EROSION CONTROL CONCEPT 18
E. EROSION CONTROL ESCROW ESTIMATE 18
REFERENCES 19
APPENDIX
PAGE
VICINITY MAP A
RATIONAL METHOD HYDROLOGY, POND SIZING & LID’s B
STORM SEWER PIPE SIZING C
INLET & CONCRETE SIDEWALK CULVERT SIZING D
SWALE SIZING E
EROSION CONTROL & RIPRAP SIZING F
PROPOSED AND EXISTING DRAINAGE BASIN EXHIBITS G
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PRELIMINARY DRAINAGE
AND EROSION CONTROL REPORT
FOR LAKEVIEW ON THE RISE
FORT COLLINS, COLORADO
I. GENERAL LOCATION AND DESCRIPTION
A. Location
The Lakeview on the Rise project is located east of and adjacent to South College
Avenue (U.S. Highway 287) and northeast of the intersection of Triangle Drive and
South College Avenue. The property is bounded to the west by South College
Avenue, to the north by an existing irrigation ditch, and to the south by Robert
Benson Reservoir, and to the east by Provincetown Filing Three subdivision.
The project site can also be described as situated in the northwest quarter of Section
13, Township 6 North, Range 69 West of the 6th P.M., City of Fort Collins, County of
Larimer, State of Colorado. The site (property boundary) comprises approximately
20.089 acres (see vicinity map in Appendix A).
B. Description of Property
The project site currently contains an existing 20.089-acre vacant field comprised of
primarily dirt with native weeds and grasses and portions of South College Avenue.
The site also contains one existing commercial building that is currently unoccupied
and will be removed prior to any proposed construction activities. Robert Benson
Reservoir and an associated wetland area bound the proposed site to the south.
The existing site has topography which generally slopes from the northwest to the
south-southeast at approximately 2.9%, with varying slopes from 2.0% to 5.0%.
The proposed development consists of 17 apartment buildings, a Clubhouse with
pool, and associated street, water, sanitary sewer, storm sewer, and private
infrastructure improvements, as well as intermittent green spaces and outdoor spaces.
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II. DRAINAGE BASINS
A. Major Basin Description
The Lakeview on the Rise project is located within the City of Fort Collins Fossil
Creek Reservoir Drainage Basin. The Fossil Creek Reservoir Drainage Basin
generally flows from the northwest to southeast and ultimately outlets into the Poudre
River.
B. Existing Sub-Basin Description
The existing site consists primarily of dirt with intermittent grasses and weeds. All
existing onsite drainage is conveyed from the northwest to the south-southeast
ultimately collecting in Robert Benson Reservoir, located along the south side of the
property. The existing subject site is contained within one existing sub-basin (EX1).
Existing basin EX1 contains approximately 21.54 acres and was modeled with the
basin having an existing ‘c’ value of 0.25. The calculated existing 2-year runoff from
basin EX1 is 6.12 cfs. Please refer to the rational calculations in Appendix B.
C. Proposed Sub-Basin Description
The proposed development consists of 17 apartment buildings, a Clubhouse with
pool, and associated street, water, sanitary sewer, storm sewer, and private
infrastructure improvements, as well as intermittent green spaces and outdoor spaces.
All flows generated from the proposed site will be conveyed to two forebay/Rain
Gardens, then to two proposed water quality and detention ponds, prior to being
released into Robert Benson Reservoir. It is important to note that a small portion of
the site (approximately 3.80 acres) along the western boundary consists of portions of
South College Avenue and undeveloped land that is conveyed directly into Robert
Benson Reservoir without detention or treatment, as historically occurs. All flows
released into Robert Benson Reservoir will ultimately be conveyed to Fossil Creek
Reservoir and into the Poudre River.
The proposed public roads will be paved with asphalt, while the private drives and
adjacent parking areas will be constructed of concrete or asphalt. Interior sidewalks
will be constructed of concrete to serve pedestrians and provide access throughout
the site. Runoff from the proposed site will be ultimately conveyed in two large spine
storm drainage piping systems that will flow south towards the two proposed
detention ponds.
Distribution boxes, with multiple 12” ADS pipes installed out of the sides of the
boxes, will be installed near the downstream ends of the two large spine storm
drainage systems. The 12” ADS pipes will convey runoff from the site to the two
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proposed forebay/Rain Garden basins. The forebays/Rain Gardens will have graded
cobble installed 24” deep with 8” perforated underdrain system piping installed at the
bottom of the cobble. One foot of freeboard depth will also be provided above the
graded cobble to meet the LID criteria of 1’ depth. Upon the forebays/ Rain Gardens
filling up with runoff from the site, runoff will be filtered through the graded cobble
and will discharge into the proposed water quality/detention ponds via the 8”
perforated pipes/underdrains. Per the Geotechnical report by Terracon, the site
contains highly expansive clay materials, and as required, all roof drainage from the
site and as much site area as possible, is required to be captured immediately by
piping systems and conveyed away from the buildings and road infrastructure.
Therefore, in meeting the requirements of the Geotechnical Report, the proposed
forebays/Rain Gardens will be provided to mitigate infiltration of runoff into the sub-
grade, as required, and to provide LID treatment for approximately 82 percent of the
total site which includes the offsite area.
Should the forebays/Rain Gardens fill up during major storm events, the
forebays/Rain Gardens will overtop south and to the proposed water quality/detention
ponds.
The proposed water quality and detention ponds will be graded with relatively flat
bottoms (0.5% to 2.0%) to allow for infiltration and pollutants to settle out of the
runoff, prior to flows exiting the ponds via the proposed outlet structures and into
Robert Benson Reservoir.
The proposed water quality/ detention ponds will discharge the combined 2-year
historic release rate (6.12 cfs) directly into Robert Benson Reservoir.
III. DRAINAGE BASIN CRITERIA
A. Regulations
The drainage design for the subject site is required to meet the current City of Fort
Collins Stormwater and Erosion Control Standards and requirements, as well as the
requirements of the Geotechnical Report by Terracon. Therefore, the drainage design
for the subject site has been designed in accordance with these standards and
provides for the site drainage being conveyed to downstream LID/Rain Gardens and
water quality/detention areas, as required and applicable. The proposed project will
be required to provide water quality and on-site detention, prior to the 2-year historic
release rate from the site being conveyed into Robert Benson Reservoir, as
historically occurs.
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B. Development Criteria Reference and Constraints
Drainage criteria and constraints required by the City of Fort Collins and Terracon
will be achieved and provided by the Lakeview on the Rise project. The capacity of
the system will be self contained and release to Robert Benson Reservoir at a rate not
to exceed the 2-year historic release rate of 6.12 cfs for the entire 21.54 acres, which
includes all attributing onsite and offsite basins, including the half-width of South
College Avenue along the proposed site.
C. Hydrologic Criteria
The Rational Method for determining surface runoff was used for the project site.
The 2-year and 100-year storm event intensities were used in calculating runoff
values. The City of Fort Collins intensity duration frequency curves were used to
obtain rainfall data for each storm specified.
Detention and water quality pond sizing was calculated using the latest City of Fort
Collins Criteria as well as Urban Drainage Flood Control District sizing methods.
Forebarys/Rain Gardens sizing was calculated using the Design Procedure Form for
Rain Garden Design spreadsheet developed by UDFCD.
D. Hydraulic Criteria
All hydraulic calculations within this report have been prepared in accordance with
the City of Fort Collins Drainage Criteria and are also included in the Appendices.
Final storm sewer pipe and inlet/curb cut sizing will be completed during final design
using UDSewer and UDInlet from UDFCD, as well as other orifice/inlet control
sizing spreadsheets. Final Swale sizing will also be completed during final design
using AutoCad Civil 3D Hydraulic Software, while final erosion control/riprap sizing
will be calculated using North American Green software.
E. Variances
No variances are being requested at this time.
IV. DRAINAGE FACILITY DESIGN
A. General Concept
Twenty-nine proposed onsite drainage basins and one offsite basin have been created
to analyze the drainage for the proposed development.
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Basins 1-15 drain ultimately to a proposed detention/water quality pond located in the
southwest corner of the site via overland flow, curb and gutter, and proposed storm
sewer systems. The 100-year peak flow to be detained in the detention pond located
in the southwest corner of the site will be approximately 39 cfs.
Basins 16-29 drain ultimately to a second proposed detention/water quality pond
located in the southeast corner of the site via overland flow, curb and gutter, and
proposed storm sewer systems. The 100-year peak flow to be detained in the
detention pond located in the southeast corner of the site will be approximately 35
cfs.
Basin OS1 is an offsite basin that consists of portions of South College Avenue that
will be conveyed directly to Robert Benson Reservoir undetained.
The total 100-year peak flow to be detained in the two proposed detention ponds
located onsite will be approximately 67 cfs.
Detention Pond 100 (west) and Detention Pond 200 (east) provide approximately
3.12 acre-feet and 1.77 acre-feet of storage, respectively, which provide for the
combination of detention and water quality, while having an allowed 2-year release
rate of 6.12 cfs. The release rate for Pond 100 and Pond 200 will be 1.0 cfs and 5.12
cfs respectively. It's important to note that Pond 100 and Pond 200 have been sized
to detain up to the 100-year event, while receiving the 100-year developed flow (66.9
cfs) from 21.54 acres, with the calculated overall 'c' value for the site being 0.72,
versus the overall combined existing 'c' value of 0.25.
Please refer to the rational calculations in Appendix B and the Proposed and Existing
Drainage Basin Exhibits in Appendix G for additional information. The inlets and
storm sewer system will be sized with final design.
B. Specific Details
Drainage to Detention Pond 100:
The runoff from the following basins 1-15 will be collected in a proposed storm
sewer system which will be ultimately be conveyed to a Detention Pond 100 located
at the southwest corner of the site.
Basin 1
Runoff in Basin 1 will be conveyed via overland flow and curb and gutter to a
5’ Type R inlet. The 5’ Type R inlet discharges into a proposed storm sewer
system at design point 1.
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Basin 2
Runoff in Basin 2 will be conveyed via roof drains, overland flow, and a
grass lined swale to the proposed storm sewer system at design point 2.
Basin 3
Runoff in Basin 3 will be conveyed via overland flow, a grass lined swale and
curb and gutter to a 5’ Type R inlet. Flows from the grass lined swale will
pass through a curb cut and join runoff collected from the proposed roadway
as it passes to the 5’ Type R inlet via curb and gutter. The 5’ Type R inlet
discharges into a proposed storm sewer system at design point 3.
Basin 4
Runoff in Basin 4 will be conveyed via overland flow and curb and gutter.
Runoff from the north side of Lorien Lane and the west half of Debra Drive
flows to a 5’ Type R, on grade inlet. The 5’ Type R inlet discharges into a
proposed storm sewer system at design point 4.
Basin 5
Runoff in Basin 5 will be conveyed via roof drains, overland flow and curb
and gutter. Runoff in the east half of Debra Drive flows to a 5’ Type R inlet,
on grade inlet. The 5’ Type R inlet discharges into a proposed storm sewer
system at design point 5.
Basin 6
Runoff in Basin 6 will be conveyed via roof drains, overland flow, and a
grass lined swale to the proposed storm sewer system at design point 6.
Basin 7
Runoff in Basin 7 will be conveyed via roof drains, overland flow and curb
and gutter to a 5’ Type R inlet. The 5’ Type R inlets discharges into a
proposed storm sewer system at design point 7.
Basin 8
Runoff in Basin 8 will be conveyed via roof drains, overland flow, and a
grass lined swale to a 2’ diameter Nyloplast area inlet. The 2’ diameter
Nyloplast area inlet discharges into a proposed storm sewer system at design
point 8.
Basin 9
Runoff in Basin 9 will be conveyed via roof drains, overland flow, a grass
lined swale, and curb and gutter to two, 5’ Type R inlets. The 5’ Type R
inlets discharge into a proposed storm sewer system at design point 9.
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Basin 10
Runoff in Basin 10 will be conveyed via roof drains, overland flow and curb
and gutter to a 5’ Type R inlet. The 5’ Type R inlet discharges into a
proposed storm sewer system at design point 10.
Basin 11
Runoff in Basin 11 will be conveyed via overland flow and curb and gutter to
a 5’ Type R inlet. The 5’ Type R inlet discharges into a proposed storm
sewer system at design point 11.
Basin 12
Runoff in Basin 12 will be conveyed via roof drains, overland flow and curb
and gutter to a 5’ Type R inlet. The 5’ Type R inlet discharges into a
proposed storm sewer system at design point 12.
Basin 13
Runoff in Basin 13 will be conveyed via overland flow, a grass lined swale
and curb and gutter to a 5’ Type R inlet. Flow from the grass lined swale will
pass through a curb cut and join runoff collected from the south half of the
proposed Debra Drive roadway. Flow is intercepted by a proposed 5’ Type R
on grade inlet at design point 13. The 5’ Type R inlet discharges into a
proposed storm sewer system at design point 13. Carry over runoff will flow
to design point 28.
Basin 14
Runoff in Basin 14 will be conveyed via overland flow and a grass lined
swale to the proposed detention pond located in the southwest portion of the
site at design point 14.
Basin 15
Runoff in Basin 15 will be conveyed via overland flow to the proposed
Detention Pond 100 located in the southwest portion. The basin includes the
proposed Detention Pond 100, located in the southwest portion of the site.
Runoff is released at a controlled rate via a water quality control structure at
design point 15.
Drainage to Detention Pond 200:
The runoff from the following basins 16-29 will be collected in a proposed storm
sewer system which will be ultimately be conveyed to Detention Pond 200 located at
the southeast corner of the site.
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Basin 16
Runoff in Basin 16 will be conveyed via roof drains, overland flow and curb
and gutter to a 5’ Type R inlet. The 5’ Type R inlet discharges into a
proposed storm sewer system at design point 16.
Basin 17
Runoff in Basin 17 will be conveyed via roof drains, overland flow, and a
grass lined swale to a 2’ diameter Nyloplast area inlet. The 2’ diameter
Nyloplast area inlet discharges into a proposed storm sewer system at design
point 17.
Basin 18
Runoff in Basin 18 will be conveyed via roof drains, overland flow, and curb
and gutter to a 5’ Type R inlet. The 5’ Type R inlet discharges into a
proposed storm sewer system at design point 18.
Basin 19
Runoff in Basin 19 will be conveyed via overland flow, a grass lined swale,
and curb and gutter to a 2’ diameter Nyloplast area inlet. Flows from the curb
and gutter will pass through a curb cut and join runoff collected from the
grass lined swale as it passes to the 2’ diameter Nyloplast area inlet. The 2’
diameter Nyloplast area inlet discharges into a proposed storm sewer system
at design point 19.
Basin 20
Runoff in Basin 20 will be conveyed via roof drains, overland flow, a grass
lined swale to a 2’ diameter Nyloplast area inlet. The 2’ diameter Nyloplast
area inlet discharges into a proposed storm sewer system at design point 20.
Basin 21
Runoff in Basin 21 will be conveyed via roof drains, overland flow and curb
and gutter to a 5’ Type R inlet. The 5’ Type R inlet discharges into a
proposed storm sewer system at design point 21.
Basin 22
Runoff in Basin 22 will be conveyed via overland flow and curb and gutter to
a 5’ Type R inlet. The 5’ Type R inlet discharges into a proposed storm
sewer system at design point 22.
Basin 23
Runoff in Basin 23 will be conveyed via roof drains, overland flow, a grass
lined swale and curb and gutter to a 4’ x 4’, CDOT Type C inlet. Flows from
the curb and gutter will pass through a curb cut and join runoff collected from
the grass lined swale as it passes to the 4’ x 4’, CDOT Type C inlet. The 4’ x
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4’, Type C inlet discharges into a proposed storm sewer system at design
point 23.
Basin 24
Runoff in Basin 24 will be conveyed via roof drains, overland flow, a grass
lined swale to a 2’ diameter Nyloplast area inlet. The 2’ diameter Nyloplast
area inlet discharges into a proposed storm sewer system at design point 24.
Basin 25
Runoff in Basin 25 will be conveyed via roof drains, overland flow, a grass
lined swale to a 2’ diameter Nyloplast area inlet. The 2’ diameter Nyloplast
area inlet discharges into a proposed storm sewer system at design point 25.
Basin 26
Runoff in Basin 26 will be conveyed via roof drains, overland flow, a grass
lined swale to a 2’ diameter Nyloplast area inlet. The 2’ diameter Nyloplast
area inlet discharges into a proposed storm sewer system at design point 26.
Basin 27
Runoff in Basin 27 will be conveyed via overland flow to curb and gutter.
Flow in the north and east half of the proposed roadway will drain to a 10’
Type R sump inlet. The 10’ Type R inlet discharges into a proposed storm
sewer system at design point 27.
Basin 28
Runoff in Basin 28 from the south half of the roadway, will be conveyed via
overland flow and curb and gutter to a 10’ Type R sump inlet on Stoney
Brook Road. The 10’ Type R inlet discharges into a proposed storm sewer
system at design point 28.
Basin 29
Runoff in Basin 29 will be conveyed via overland flow. The basin includes
the proposed Detention Pond 200, located in the southeast portion of the site.
Runoff is released at a controlled rate via a water quality control structure at
design point 29.
Offsite Drainage
The runoff from the following basin drains offsite.
Basin OS1
Runoff in Basin OS1 will be conveyed via overland flow and curb and gutter
to Robert Benson Reservoir south of the site. The flows in Basin OS1
represent a portion of South College Avenue and undeveloped land in the
southwest corner of the site. Runoff in College Avenue will be intercepted by
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a 5’ Type R inlet and 10’ Type R inlet in the east flowline. Flow is piped to
existing swales and discharges to Benson Reservoir. Runoff in OS1 will be
released undetained.
Overflow Conditions
Basins 1-5: Should the inlets at the low points in these basins become obstructed
and fail to collect the required drainage, the runoff will pass to Debra Drive and
ultimately be conveyed to the detention pond located in the southwest corner of the
site.
Basins 6-12: Should the inlets at the low points in these basins become obstructed
and fail to collect the required drainage, the runoff will pass through the proposed
parking areas to Debra Drive and ultimately be conveyed to Detention Pond 100
located in the southwest corner of the site.
Basin 13: Should the on-grade inlet at design point 13 in this basin become
obstructed and fail to collect the required drainage, the runoff will pass to the low
point in Stoney Brook Drive and ultimately be conveyed to Detention Pond 200
located in the southeast corner of the site.
Basin 14-15: Should the on-grade inlet at design point 13 in this basin become
obstructed and fail to collect the required drainage, the runoff will pass to the low
point in Stoney Brook Drive and ultimately be conveyed to Detention Pond 200
located in the southeast corner of the site.
Basins 16-22: Should the inlets at the low points in these basins become obstructed
and fail to collect the required drainage, the runoff will pass through the private drive
into Stoney Brook Road and ultimately be conveyed to Detention Pond 200 located
in the southeast corner of the site.
Basin 23: Should the CDOT Type C inlet at the low point in this basin become
obstructed and fail to collect the required drainage, the runoff will pass into Stoney
Brook Road and ultimately be conveyed to Detention Pond 200 located in the
southeast corner of the site.
Basins 24-26: Should the inlets at the low points in these basins become obstructed
and fail to collect the required drainage, the runoff will pass to the low point in
Stoney Brook Drive and ultimately be conveyed to Detention Pond 200 located in the
southeast corner of the site.
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Basins 27-28: Should the inlets at the low points in these basins located at the low
point in Stoney Brook Drive become obstructed and fail to collect the required
drainage, the runoff will pass to Detention Pond 200 located in the southeast corner
of the site.
C. Detention Pond
Detention Pond 100 has been sized to provide water quality and detention for 8.57
acres of the total 21.54 acres of on-site and off-site areas. Detention Pond 100 will
provide 3.12 acre-feet of available volume at an elevation of 5016.00, (0.173 ac-ft for
water quality at an elevation of approximately 5012.40; 1.66 ac-ft of detention and
water quality at an elevation of approximately 5014.95).
Detention Pond 200 has been sized to provide water quality and detention for the
9.18 acres of the total 21.54 acres of on-site and off-site areas. Detention Pond 200
will provide 1.77 acre-feet of available volume (0.19 ac-ft for water quality within at
an elevation of approximately 5006.00; 1.77 ac-ft of detention at an elevation of
approximately 5008.47).
The proposed detention ponds will allow for detention up to the 100-year storm event
for the development. The lowest outlet elevation of the Detention Pond 100 (invert
at the front of the outlet structure) is approximately 5010.00. The calculated 100-
year water surface elevation of Detention Pond 100 is approximately 5014.95 with a
release rate of 1.0 cfs.
The lowest outlet elevation of the Detention Pond 200 (invert at the front of the outlet
structure) is approximately 5003.00. The calculated 100-year water surface elevation
of Detention Pond 200 is approximately 5008.47 .
The proposed water quality/detention pond outlet structures will be 18” RCP pipes
with orifice control plates at the entrance of the pipes. Orifice sizing will be provided
at final design, thus discharging the allowable 2-year historic release rate of 6.12 cfs
combined into Robert Benson Reservoir.
An Emergency Spillway will also be sized at final design and will be constructed
along the south edges of Pond 100 and Pond 200. The proposed spillways on Pond
100 and Pond 200 will have overflow elevations of 5016.00 and 5009.00,
respectively, with widths sized at final design. Should Pond 100 and Pond 200
overtop, runoff will be released south into Robert Benson Reservoir. Please refer to
the Utility Plans for specific grading and overflow weir details.
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D. Street Capacities
Street capacity calculations for public roads have been analyzed and calculated, with
the results provided in Appendix D.
V. STORM WATER QUALITY
A. General Concept & Specific Details
The water quality of stormwater runoff must be addressed on all final design utility
plans. Therefore, Best Management Practices (BMP's) for the treatment of
stormwater runoff for the subject site will include grass/ sod-lined swales, riprap pads
at culvert discharge points, permanent erosion control fabric at curb cuts and swale
entrances into the ponds, grass scrubbing across the bottom of the detention ponds
during first flush conditions, and proposed Rain Garden consisting of water quality
catch basins located at the entrances to the detention ponds which will be
incorporated into the detention pond design. These proposed water quality features
will provide a mechanism for pollutants to settle out of the stormwater runoff before
flows are directed into the detention ponds and ultimately to Robert Benson
Reservoir.
The proposed water quality/ detention facilities have adequate capacity and will
provide all of the required water quality and detention up to the 100-year event for
the developed condition of the subject site (21.54 acres), prior to releasing flows to
Robert Benson Reservoir.
VI. EROSION CONTROL
A. General Concept
Silt fence will be installed along the north, west, south, east and west property
boundaries of the site to prevent sediment from leaving the site. In addition, silt
fence is proposed around the perimeter of each block of buildings surrounded by curb
and gutter to prevent sediment from entering proposed drive aisles and streets. A
vehicle tracking pad will be placed at the site access point at US 287 and Lorien
Lane. The exact location shall be provided during final design.
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Straw Wattles and gravel inlet filters will be placed at proposed inlet locations to
mitigate the build-up of sediment in the proposed inlet and manhole structures.
Straw wattle check dams will also be installed at 300' intervals in the proposed
swales throughout the site, as may be applicable.
Erosion Control Calculations and the Erosion Control Escrow Amount will be
provided during final design. Please refer to Appendix G for the Erosion Control
Plan and Erosion Control Notes and Detail Sheets.
VII. CONCLUSIONS
A. Compliance with Standards & Stormwater Operations/Maintenance Procedure
All computations within this report have been completed in compliance with the City
of Fort Collins Storm Drainage Design Criteria.
The City of Fort Collins Storm water Utility will not maintain the on-site storm
drainage facilities within the subject site. The owners of the subject site will
maintain their on-site storm drainage facilities on a regular basis. The following shall
be implemented for the private stormwater improvements’ operations/ maintenance
procedures for the project on an annual or bi-annual basis:
1) Storm Sewer Inlets, pipes and flared-end-sections, curb cuts and concrete
sidewalk culverts/chases, structures, manholes, and the LID water quality
catch basins shall be cleaned through the removal of debris and sediment
from the associated items to allow for adequate drainage through the site to
the proposed detention facilities.
2) Pond sedimentation/ silting shall be removed to allow for adequate drainage
along the bottom of the ponds and to prevent ponding and silting in of the
pond bottoms. Grass scrubbing along the bottom of the ponds may be
required to remove sediment and promote grass growth.
3) Re-vegetation through the use of Natural Seeding/ Sod shall be provided for
disturbed areas and other permanent erosion controls shall be provided for
areas where erosion has taken place and requires remediation back to the
proposed condition shown in the plans.
The Stormwater Operating/ Maintenance Procedures listed above are guidelines to
the minimum procedures that shall be implemented for the site, with these and
additional measures being utilized on an as-needed basis.
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B. Drainage Concept
The proposed drainage concepts presented in this study and shown on the utility
plans adequately provide for the transmission of developed on-site runoff to the
proposed detention ponds (Pond 100 and Pond 200), located southwest and southeast
corners of the subject site. The proposed storm sewer system will provide for the
100-year developed flows to reach the proposed water quality and detention ponds,
prior to flows being released downstream in accordance with the 2-year historic
release rate of 6.12 cfs.
If groundwater is encountered at the time of construction, a Colorado Department of
Health Construction Dewatering Permit will be required.
C. Storm Water Quality
The preliminary design has addressed the water quality aspect of stormwater runoff.
The proposed grass-lined detention ponds and Rain Gardens will provide an
opportunity for stormwater pollutants to filter out of the stormwater runoff before
flows are directed downstream to Robert Benson Reservoir.
Furthermore, the proposed grass-sod-lined swales, riprap pads at culvert outlets,
permanent erosion control fabric and other erosion control devises that may be
utilized for side-slopes and embankments, grass scrubbing across the bottom of the
detention ponds during first flush conditions, and the water quality basins
incorporated into the detention pond designs will provide additional mechanisms for
pollutants to settle out of the stormwater runoff before flows are directed south and
ultimately to Robert Benson Reservoir.
D. Erosion Control Concept
Proposed erosion control concepts will adequately provide for the control of wind
and rainfall erosion from the proposed development. Through the construction of the
proposed erosion control concepts, the City of Fort Collins standards will be
maintained. The proposed erosion control concepts presented in the preliminary
report and shown on the erosion control plan are in compliance with the City of Fort
Collins Erosion Control Criteria.
E. Erosion Control Escrow Estimate
The Erosion Control Escrow Estimate for the subject property will be provided at
final design.
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REFERENCES
1. Storm Drainage Design Criteria and Construction Standards by the City of Fort Collins,
Colorado, May 1984, Revised January 1997, & Associated UDFCD Updates and New City
of Fort Collins Stormwater Criteria manual, adopted January, 2012.
2. Erosion Control Reference Manual for Construction Sites by the City of Fort Collins,
Colorado, January 1991, Revised January 1997, & Associated UDFCD Updates and New
City of Fort Collins Stormwater Criteria manual, adopted January, 2012.
3. Urban Storm Drainage Criteria Manual Volume 1; Urban Drainage and Flood Control
District, Denver, Colorado, June 2001.
4. Urban Storm Drainage Criteria Manual Volume 2; Urban Drainage and Flood Control
District, Denver, Colorado, June 2001.
5. Urban Storm Drainage Criteria Manual Volume 3, Best Management Practices; Urban
Drainage and Flood Control District, Denver, Colorado, August 2011.
17
APPENDIX
18
APPENDIX A
19
VICINITY MAP
VICINITY MAP
VICINITY MAP
20
APPENDIX B
21
RATIONAL METHOD
HYDROLOGY
TIME OF CONCENTRATION
2 year design storm
Lakeview on the Rise
801-002
t c = t i + t L
C f = 1.00
SUB-BASIN DATA INITIAL/OVERLAND TIME TRAVEL TIME FINAL REMARKS
BASIN AREA C LENGTH SLOPE ti LENGTH CHANNEL SLOPE VELOCITY tL tc
NO. (ac) (ft) (%) (min) (ft) TYPE(a) (%) (ft/s) (min) (min)
1 2 3 4 5 6 7 8 10 12 13
1 0.39 0.86 156 3.7 3.6 135 PA 2.8 3.23 0.7 5.0 Drains to West Detention Pond
2 0.46 0.72 20 20.0 1.2 316 GW 5.0 3.44 1.5 5.0 Drains to West Detention Pond
3 0.24 0.73 26 16.0 1.4 275 PA 3.7 3.73 1.2 5.0 Drains to West Detention Pond
4 0.95 0.56 328 2.6 13.3 290 PA 2.4 2.99 1.6 14.9 Drains to West Detention Pond
5 0.47 0.74 38 3.8 2.6 292 PA 2.4 2.99 1.6 5.0 Drains to West Detention Pond
6 0.27 0.66 14 14.5 1.3 178 GW 2.2 2.28 1.3 5.0 Drains to West Detention Pond
7 0.40 0.83 122 4.3 3.4 49 PA 3.5 3.62 0.2 5.0 Drains to West Detention Pond
8 0.26 0.80 5 5.0 0.7 135 GW 2.0 2.18 1.0 5.0 Drains to West Detention Pond
9 0.62 0.83 236 2.8 5.5 65 PA 3.0 3.35 0.3 5.8 Drains to West Detention Pond
10 0.51 0.82 130 2.2 4.5 12 PA 2.0 2.72 0.1 5.0 Drains to West Detention Pond
11 0.19 0.72 139 2.5 6.2 22 PA 1.3 2.18 0.2 6.4 Drains to West Detention Pond
12 0.22 0.83 86 2.5 3.4 16 PA 1.3 2.18 0.1 5.0 Drains to West Detention Pond
t
CC D
i S
f
187 11
0 333
. ( . )
.
13 0.49 0.66 11 12.3 1.2 461 PA 2.1 2.79 2.8 5.0 Drains to West Detention Pond
14 0.46 0.26 14 2.4 4.4 582 GW 3.6 2.92 3.3 7.7 Drains to West Detention Pond
15 2.65 0.25 186 3.6 14.1 138 GW 1.0 1.54 1.5 15.6 Drains to West Detention Pond
16 1.03 0.77 245 2.5 7.2 120 PA 1.0 1.91 1.0 8.3 Drains to East Detention Pond
17 0.27 0.75 14.5 5.4 1.4 186 GW 2.0 2.18 1.4 5.0 Drains to East Detention Pond
18 0.46 0.85 112 3.0 3.5 65 PA 2.0 2.72 0.4 5.0 Drains to East Detention Pond
19 0.22 0.48 15 12.8 1.9 134 GW 3.3 2.80 0.8 5.0 Drains to East Detention Pond
20 0.64 0.74 15 12.8 1.1 268 GW 2.0 2.18 2.1 5.0 Drains to East Detention Pond
21 0.65 0.83 193 1.8 5.8 140 PA 2.0 2.72 0.9 6.6 Drains to East Detention Pond
22 0.30 0.83 150 3.0 4.3 86 PA 2.6 3.11 0.5 5.0 Drains to East Detention Pond
23 1.58 0.44 178 2.0 13.1 811 GW 2.0 2.18 6.2 19.4 Drains to East Detention Pond
24 0.18 0.65 28 13.7 1.9 67 GW 2.0 2.18 0.5 5.0 Drains to East Detention Pond
25 0.82 0.57 29 5.5 3.0 209 GW 1.5 1.89 1.8 5.0 Drains to East Detention Pond
26 0.24 0.41 29 5.0 4.1 268 GW 2.0 2.18 2.1 6.1 Drains to East Detention Pond
27 0.63 0.78 103 3.2 4.1 147 PA 1.8 2.58 1.0 5.0 Drains to East Detention Pond
28 0.34 0.77 32 3.0 2.4 272 PA 1.8 2.58 1.8 5.0 Drains to East Detention Pond
29 1.82 0.28 160 12.0 8.4 223 GW 1.4 1.82 2.0 10.5 Drains to East Detention Pond
OS1 3.80 0.63 25 2.0 3.5 1545 PA 0.9 1.81 14.3 17.8 OFFSITE BASIN
Note:
a) Codes the channel type for velocity calculations.
PA = Paved, PL = Pasture & Lawns, GW = Grassed Waterway
ASPEN ENGINEERING
8:59 AM
4/19/2017
TIME OF CONCENTRATION
100 year design storm
Lakeview on the Rise
801-002
t c = t i + t L
C f = 1.25
SUB-BASIN DATA INITIAL/OVERLAND TIME TRAVEL TIME FINAL REMARKS
BASIN AREA C LENGTH SLOPE ti LENGTH CHANNEL SLOPE VELOCITY tL tc
NO. (ac) (ft) (%) (min) (ft) TYPE(a) (%) (ft/s) (min) (min)
1 2 3 4 5 6 7 8 10 12 13
1 0.39 0.86 156 3.70 1.5 135 PA 2.80 3.23 0.7 5.0
2 0.46 0.72 20 20.00 0.6 316 GW 5.00 3.44 1.5 5.0
3 0.24 0.73 26 16.00 0.7 275 PA 3.70 3.73 1.2 5.0
4 0.95 0.56 328 2.60 9.9 290 PA 2.40 2.99 1.6 11.5
5 0.47 0.74 38 3.80 1.3 292 PA 2.40 2.99 1.6 5.0
6 0.27 0.66 14 14.50 0.8 178 GW 2.20 2.28 1.3 5.0
7 0.40 0.83 122 4.30 1.3 49 PA 3.50 3.62 0.2 5.0
8 0.26 0.80 5 5.00 0.3 135 GW 2.00 2.18 1.0 5.0
9 0.62 0.83 236 2.80 2.0 65 PA 3.00 3.35 0.3 5.0
10 0.51 0.82 130 2.20 1.6 12 PA 2.00 2.72 0.1 5.0
11 0.19 0.72 139 2.50 3.3 22 PA 1.30 2.18 0.2 5.0
12 0.22 0.83 86 2.50 1.3 16 PA 1.30 2.18 0.1 5.0
t
CC D
i S
f
187 11
0 333
. ( . )
.
12 0.22 0.83 86 2.50 1.3 16 PA 1.30 2.18 0.1 5.0
13 0.49 0.66 11 12.30 0.7 461 PA 2.10 2.79 2.8 5.0
14 0.46 0.26 14 2.40 4.1 582 GW 3.60 2.92 3.3 7.4
15 2.65 0.25 186 3.60 13.1 138 GW 1.00 1.54 1.5 14.6
16 1.03 0.77 245 2.50 3.1 120 PA 1.00 1.91 1.0 5.0
17 0.27 0.75 14.5 5.40 0.6 186 GW 2.00 2.18 1.4 5.0
18 0.46 0.85 112 3.00 1.4 65 PA 2.00 2.72 0.4 5.0
19 0.22 0.48 15 12.80 1.5 134 GW 3.30 2.80 0.8 5.0
20 0.64 0.74 15 12.80 0.5 268 GW 2.00 2.18 2.1 5.0
21 0.65 0.83 193 1.80 2.1 140 PA 2.00 2.72 0.9 5.0
22 0.30 0.83 150 3.00 1.6 86 PA 2.60 3.11 0.5 5.0
23 1.58 0.44 178 2.00 11.0 811 GW 2.00 2.18 6.2 17.2
24 0.18 0.65 28 13.70 1.2 67 GW 2.00 2.18 0.5 5.0
25 0.82 0.57 29 5.50 2.2 209 GW 1.50 1.89 1.8 5.0
26 0.24 0.41 29 5.00 3.5 268 GW 2.00 2.18 2.1 5.5
27 0.63 0.78 103 3.20 1.6 147 PA 1.80 2.58 1.0 5.0
28 0.34 0.77 32 3.00 1.0 272 PA 1.80 2.58 1.8 5.0
29 1.82 0.28 160 12.00 7.7 223 GW 1.40 1.82 2.0 9.8
OS1 3.80 0.63 25 2.00 2.3 1545 PA 0.90 1.81 14.3 16.6
Note:
a) Codes the channel type for velocity calculations.
PA = Paved, PL = Pasture & Lawns, GW = Grassed Waterway
ASPEN ENGINEERING
8:59 AM
4/19/2017
Basin Roof Area (sqft) Asphalt Area (sqft) Concrete Area (sqft) Gravel Area (sqft) Lawn Area (sqft) Total Area Total Area Composite
No. "C=0.90" "C=0.95" "C=0.90" "C=0.41" "C=0.25" (sqft) (acre) "C"
1 1,044 10,355 3,687 0 1,739 16,825 0.39 0.86
2 13,786 0 532 0 5,543 19,861 0.46 0.72
3 0 4,567 2,770 0 3,114 10,451 0.24 0.73
4 0 11,807 6,154 3,019 20,280 41,260 0.95 0.56
5 6,588 5,180 3,258 0 5,292 20,318 0.47 0.74
6 6,272 0 988 0 4,348 11,608 0.27 0.66
7 6,272 7,234 1,554 0 2,461 17,521 0.40 0.83
8 9,392 0 0 0 1,780 11,172 0.26 0.80
9 1,558 17,217 4,178 0 4,250 27,203 0.62 0.83
10 12,466 5,310 1,485 0 3,009 22,270 0.51 0.82
11 0 3,530 2,156 0 2,614 8,300 0.19 0.72
12 4,218 2,884 1,096 0 1,216 9,414 0.22 0.83
13 1,044 7,268 4,606 0 8,443 21,361 0.49 0.66
14 0 0 165 0 19,785 19,950 0.46 0.26
15 0 0 433 0 115,171 115,604 2.65 0.25
16 6,346 20,573 6,929 0 10,852 44,700 1.03 0.77
17 8,766 0 447 0 2,700 11,913 0.27 0.75
Developed Weighted Runoff Coefficients
Lakeview on the Rise
801-002
17 8,766 0 447 0 2,700 11,913 0.27 0.75
18 8,766 6,952 2,142 0 2,132 19,992 0.46 0.85
19 1,044 150 2,226 0 6,142 9,562 0.22 0.48
20 20,052 0 1,216 0 6,673 27,941 0.64 0.74
21 5,790 13,735 4,492 0 4,092 28,109 0.65 0.83
22 0 8,924 2,044 0 2,076 13,044 0.30 0.83
23 9,809 5,632 2,331 6,386 44,771 68,929 1.58 0.44
24 4,594 0 144 0 2,946 7,684 0.18 0.65
25 10,028 0 7,789 0 17,938 35,755 0.82 0.57
26 0 0 2,465 0 7,832 10,297 0.24 0.41
27 0 14,495 6,978 0 6,077 27,550 0.63 0.78
28 0 8,453 2,744 0 3,603 14,800 0.34 0.77
29 0 0 4,038 0 75,398 79,436 1.82 0.28
OS1 0 73,990 16,700 0 74,768 165,458 3.80 0.63
Total SITE 137,835 228,256 95,747 9,405 467,045 938,288 21.54 0.58
Total Acreage 3.16 5.24 2.20 0.22 10.72 21.54
aspen engineering
9:02 AM
4/19/2017
Impervious Ratio
Basin Roof Area (sqft) Asphalt Area (sqft) Concrete Area (sqft) Gravel Area (sqft) Lawn Area (sqft) Total Area Imperviousness
No. (sqft) Ratio
1 1,044 10,355 3,687 0 1,739 16,825 90%
2 13,786 0 532 0 5,543 19,861 67%
3 0 4,567 2,770 0 3,114 10,451 72%
4 0 11,807 6,154 3,019 20,280 41,260 49%
5 6,588 5,180 3,258 0 5,292 20,318 72%
6 6,272 0 988 0 4,348 11,608 59%
7 6,272 7,234 1,554 0 2,461 17,521 83%
8 9,392 0 0 0 1,780 11,172 76%
9 1,558 17,217 4,178 0 4,250 27,203 85%
10 12,466 5,310 1,485 0 3,009 22,270 82%
11 0 3,530 2,156 0 2,614 8,300 70%
12 4,218 2,884 1,096 0 1,216 9,414 83%
13 1,044 7,268 4,606 0 8,443 21,361 62%
14 0 0 165 0 19,785 19,950 6%
15 0 0 433 0 115,171 115,604 5%
16 6,346 20,573 6,929 0 10,852 44,700 76%
17 8,766 0 447 0 2,700 11,913 71%
18 8,766 6,952 2,142 0 2,132 19,992 85%
19 1,044 150 2,226 0 6,142 9,562 38%
20 20,052 0 1,216 0 6,673 27,941 70%
21 5,790 13,735 4,492 0 4,092 28,109 84%
22 0 8,924 2,044 0 2,076 13,044 85%
23 9,809 5,632 2,331 6,386 44,771 68,929 31%
24 4,594 0 144 0 2,946 7,684 58%
25 10,028 0 7,789 0 17,938 35,755 50%
26 0 0 2,465 0 7,832 10,297 28%
27 0 14,495 6,978 0 6,077 27,550 79%
28 0 8,453 2,744 0 3,603 14,800 77%
29 0 0 4,038 0 75,398 79,436 10%
OS1 0 73,990 16,700 0 74,768 165,458 57%
Total SITE 137,835 228,256 95,747 9,405 467,045 938,288 51%
Total Acreage 3.16 5.24 2.20 0.22 10.72 21.54 51%
aspen engineering
9:02 AM
4/19/2017
Business:
Commercial areas
Neighborhood areas
Residential:
Single-family
Multiunit (detached)
Multiunit (attached)
Half-acre lot or larger
Apartments
Industrial:
Light areas
Heavy areas
Parks, cemeteries:
Playgrounds:
Schools:
Railroad yard areas:
Undeveloped areas:
Historical Flow Analysis
Greenbelts, agricultural
Off-site flow analysis
(when land use not defined)
Streets:
Paved
Gravel (packed)
Driveways and sidewalks:
Roofs:
Lawns, sandy soil
Lawns, clayey soil
*Refer to Figures RO-3 through RO-5 in Runoff Chapter
Land Use or Surface Characteristics Percent Imper-viousness
95
85
*
60
75
*
80
80
90
5
10
50
15
2
45
0
0
100
40
90
90
aspen engineering
9:46 PM
2/13/2017
Rational Method
2 Year Design Storm
Lakeview on the Rise
801-002
Design Point Basins tc
Length Type Slope Velocity Travel
Pipe
Travel tc'
C Intensity Area
Direct
Runoff
Other
Runoff
Total
Runoff
Location (min) (ft) (a) (%) (ft/s) (min) (min) (min) (in/hr) (ac) (cfs) (cfs) (cfs)
1 1 5.0 -- -- -- -- 0.0 0.0 5.0 0.86 2.85 0.39 0.95 0.00 0.95
2 2 5.0 -- -- -- -- 0.0 0.0 5.0 0.72 2.85 0.46 0.93 0.00 0.93
3 3 5.0 -- -- -- -- 0.0 0.0 5.0 0.73 2.85 0.24 0.50 0.00 0.50
4 4 14.9 -- -- -- -- 0.0 0.0 14.9 0.56 1.87 0.95 0.99 0.00 0.99
5 5 5.0 -- -- -- -- 0.0 0.0 5.0 0.74 2.85 0.47 0.99 0.00 0.99
6 6 5.0 -- -- -- -- 0.0 0.0 5.0 0.66 2.85 0.27 0.50 0.00 0.50
7 7 5.0 -- -- -- -- 0.0 0.0 5.0 0.83 2.85 0.40 0.95 0.00 0.95
8 8 5.0 -- -- -- -- 0.0 0.0 5.0 0.80 2.85 0.26 0.58 0.00 0.58
9 9 5.8 -- -- -- -- 0.0 0.0 5.8 0.83 2.71 0.62 1.41 0.00 1.41
10 10 5.0 -- -- -- -- 0.0 0.0 5.0 0.82 2.85 0.51 1.20 0.00 1.20
11 11 6.4 -- -- -- -- 0.0 0.0 6.4 0.72 2.63 0.19 0.36 0.00 0.36
12 12 5.0 -- -- -- -- 0.0 0.0 5.0 0.83 2.85 0.22 0.51 0.00 0.51
13 13 5.0 -- -- -- -- 0.0 0.0 5.0 0.66 2.85 0.49 0.92 0.00 0.92
14 14 7.7 -- -- -- -- 0.0 0.0 7.7 0.26 2.45 0.46 0.29 0.00 0.29
15 15 15.6 -- -- -- -- 0.0 0.0 15.6 0.25 1.83 2.65 1.23 0.00 1.23
16 16 8.3 -- -- -- -- 0.0 0.0 8.3 0.77 2.39 1.03 1.87 0.00 1.87
Routing Flow Time (tL Runoff
)
17 17 5.0 -- -- -- -- 0.0 0.0 5.0 0.75 2.85 0.27 0.59 0.00 0.59
18 18 5.0 -- -- -- -- 0.0 0.0 5.0 0.85 2.85 0.46 1.11 0.00 1.11
19 19 5.0 -- -- -- -- 0.0 0.0 5.0 0.48 2.85 0.22 0.30 0.00 0.30
20 20 5.0 -- -- -- -- 0.0 0.0 5.0 0.74 2.85 0.64 1.36 0.00 1.36
21 21 6.6 -- -- -- -- 0.0 0.0 6.6 0.83 2.59 0.65 1.39 0.00 1.39
22 22 5.0 -- -- -- -- 0.0 0.0 5.0 0.83 2.85 0.30 0.71 0.00 0.71
23 23 19.4 -- -- -- -- 0.0 0.0 19.4 0.44 1.64 1.58 1.13 0.00 1.13
24 24 5.0 -- -- -- -- 0.0 0.0 5.0 0.65 2.85 0.18 0.33 0.00 0.33
25 25 5.0 -- -- -- -- 0.0 0.0 5.0 0.57 2.85 0.82 1.34 0.00 1.34
26 26 6.1 -- -- -- -- 0.0 0.0 6.1 0.41 2.67 0.24 0.26 0.00 0.26
27 27 5.0 -- -- -- -- 0.0 0.0 5.0 0.78 2.84 0.63 1.41 0.00 1.41
28 28 5.0 -- -- -- -- 0.0 0.0 5.0 0.77 2.85 0.34 0.75 0.00 0.75
29 29 10.5 -- -- -- -- 0.0 0.0 10.5 0.28 2.17 1.82 1.12 0.00 1.12
OS1 OS1 17.8 -- -- -- -- 0.0 0.0 17.8 0.63 1.72 3.80 4.10 0.00 4.10
Routing
1 1 5.0 -- 0.0 5.0 0.86 2.85 0.39 0.95 0.00 0.95
2 1,2 5.0 132.0 PA 0.4 1.2 1.8 6.8 0.79 2.56 0.84 1.70 0.00 1.70
3 1,2,3 6.8 58.0 PA 0.4 1.2 0.8 7.7 0.77 2.46 1.08 2.06 0.00 2.06
MH 1-5 7.7 113.0 PA 0.4 1.2 1.6 9.2 0.69 2.28 2.50 3.91 0.00 3.91
MH 1-5 9.2 271.0 PA 0.4 1.2 3.8 13.0 0.69 1.98 2.50 3.39 0.00 3.39
6 6 5.0 -- 0.0 5.0 0.66 2.85 0.27 0.50 0.00 0.50
7 6,7 5.0 44.0 PA 0.4 1.2 0.6 5.6 0.76 2.75 0.67 1.40 0.00 1.40
8 6-8 5.6 0.0 PA 0.4 1.2 0.0 5.6 0.77 2.75 0.93 1.96 0.00 1.96
9 6-9 5.6 150.0 PA 0.4 1.2 2.1 7.7 0.79 2.45 1.55 3.02 0.00 3.02
11 6-11 7.7 61.0 PA 0.4 1.2 0.9 8.6 0.79 2.35 2.25 4.21 0.00 4.21
12 6-12 8.6 60.0 PA 0.4 1.2 0.8 9.4 0.80 2.27 2.47 4.46 0.00 4.46
Design Point Basins tc
Length Type Slope Velocity Travel
Pipe
Travel tc'
C Intensity Area
Direct
Runoff
Other
Runoff
Total
Runoff
Location (min) (ft) (a) (%) (ft/s) (min) (min) (min) (in/hr) (ac) (cfs) (cfs) (cfs)
Routing Flow Time (tL Runoff
)
14 14 7.7 -- 0.0 7.7 0.26 2.45 0.46 0.29 0.00 0.29
15 1-15 15.1 -- 0.0 15.1 0.56 1.87 8.57 8.94 0.00 8.94
16 16 8.3 -- 0.0 8.3 0.77 2.39 1.03 1.87 0.00 1.87
17 16,17 8.3 177.0 PA 0.4 1.2 2.5 10.7 0.76 2.15 1.30 2.13 0.00 2.13
MH 16,17 10.7 31.0 PA 0.4 1.2 0.4 11.2 0.76 2.11 1.30 2.09 0.00 2.09
18 18 5.0 -- 0.0 5.0 0.85 2.85 0.46 1.11 0.00 1.11
19 18,19 5.0 29.0 PA 0.4 1.2 0.4 5.4 0.73 2.78 0.68 1.38 0.00 1.38
20 18-20 5.4 44.0 PA 0.4 1.2 0.6 6.0 0.74 2.68 1.32 2.61 0.00 2.61
21 18-21 6.0 86.0 PA 0.4 1.2 1.2 7.2 0.77 2.51 1.97 3.79 0.00 3.79
MH 18-21 7.2 18.0 PA 0.4 1.2 0.3 7.5 0.77 2.48 1.97 3.74 0.00 3.74
22 22 5.0 -- 0.0 5.0 0.83 2.85 0.30 0.71 0.00 0.71
22 16-22 11.2 173.0 PA 0.4 1.2 2.4 13.6 0.77 1.95 3.56 5.35 0.00 5.35
MH 16-22 13.6 62.0 PA 0.4 1.2 0.9 14.5 0.77 1.90 3.56 5.22 0.00 5.22
23 23 19.4 -- 0.0 19.4 0.44 1.64 1.58 1.13 0.00 1.13
MH 23 19.4 201.0 PA 0.4 1.2 2.8 22.2 0.44 1.52 1.58 1.05 0.00 1.05
MH 16-23 22.2 146.0 PA 0.4 1.2 2.0 24.2 0.67 1.45 5.15 5.00 0.00 5.00
24 24 5.0 0.0 5.0 0.65 2.85 0.18 0.33 0.00 0.33
26 24-26 5.0 139.0 PA 0.4 1.2 1.9 6.9 0.55 2.55 1.23 1.74 0.00 1.74
27 24-27 6.9 16.0 PA 0.4 1.2 0.2 7.2 0.63 2.52 1.87 2.97 0.00 2.97
MH 16-27 24.2 -- 0.0 24.2 0.66 1.45 7.01 6.71 0.00 6.71
28 16-28 24.2 5.0 PA 0.4 1.2 0.1 24.3 0.66 1.45 7.35 7.08 0.00 7.08
29 16-29 24.3 33.0 PA 0.4 1.2 0.5 24.7 0.59 1.44 9.18 7.76 0.00 7.76
ALL 1-29 24.7 24.7 0.57 1.44 17.74 14.65 0.00 14.65
OFFSITE
Note:
a) Codes the channel type for velocity calculations.
PA = Paved, PL = Pasture & Lawns, GW = Grassed Waterway
ASPEN ENGINEERING
9:09 AM
4/19/2017
Rational Method
100 Year Design Storm
Lakeview on the Rise
801-002
Design Point Basins tc
Length Type Slope Velocity Travel
Pipe
Travel tc'
C C*Cf
Intensity Area
Direct
Runoff
Other
Runoff
Total
Runoff
Location (min) (ft) (a) (%) (ft/s) (min) (min) (min) (in/hr) (ac) (cfs) (cfs) (cfs)
1 1 5.0 -- -- -- -- 0.0 0.0 5.0 0.86 1.00 9.95 0.39 3.84 0.00 3.84
2 2 5.0 -- -- -- -- 0.0 0.0 5.0 0.72 0.90 9.95 0.46 4.08 0.00 4.08
3 3 5.0 -- -- -- -- 0.0 0.0 5.0 0.73 0.91 9.95 0.24 2.17 0.00 2.17
4 4 11.5 -- -- -- -- 0.0 0.0 11.5 0.56 0.70 7.28 0.95 4.82 0.00 4.82
5 5 5.0 -- -- -- -- 0.0 0.0 5.0 0.74 0.93 9.95 0.47 4.31 0.00 4.31
6 6 5.0 -- -- -- -- 0.0 0.0 5.0 0.66 0.82 9.95 0.27 2.18 0.00 2.18
7 7 5.0 -- -- -- -- 0.0 0.0 5.0 0.83 1.00 9.95 0.40 4.00 0.00 4.00
8 8 5.0 -- -- -- -- 0.0 0.0 5.0 0.80 1.00 9.95 0.26 2.54 0.00 2.54
9 9 5.0 -- -- -- -- 0.0 0.0 5.0 0.83 1.00 9.95 0.62 6.21 0.00 6.21
10 10 5.0 -- -- -- -- 0.0 0.0 5.0 0.82 1.00 9.95 0.51 5.09 0.00 5.09
11 11 5.0 -- -- -- -- 0.0 0.0 5.0 0.72 0.90 9.95 0.19 1.70 0.00 1.70
12 12 5.0 -- -- -- -- 0.0 0.0 5.0 0.83 1.00 9.95 0.22 2.15 0.00 2.15
13 13 5.0 -- -- -- -- 0.0 0.0 5.0 0.66 0.83 9.95 0.49 4.03 0.00 4.03
14 14 7.4 -- -- -- -- 0.0 0.0 7.4 0.26 0.32 8.70 0.46 1.27 0.00 1.27
15 15 14.6 -- -- -- -- 0.0 0.0 14.6 0.25 0.32 6.60 2.65 5.53 0.00 5.53
16 16 5.0 -- -- -- -- 0.0 0.0 5.0 0.77 0.96 9.95 1.03 9.77 0.00 9.77
17 17 5.0 -- -- -- -- 0.0 0.0 5.0 0.75 0.94 9.95 0.27 2.56 0.00 2.56
18 18 5.0 -- -- -- -- 0.0 0.0 5.0 0.85 1.00 9.95 0.46 4.57 0.00 4.57
19 19 5.0 -- -- -- -- 0.0 0.0 5.0 0.48 0.60 9.95 0.22 1.32 0.00 1.32
20 20 5.0 -- -- -- -- 0.0 0.0 5.0 0.74 0.93 9.95 0.64 5.94 0.00 5.94
21 21 5.0 -- -- -- -- 0.0 0.0 5.0 0.83 1.00 9.95 0.65 6.42 0.00 6.42
22 22 5.0 -- -- -- -- 0.0 0.0 5.0 0.83 1.00 9.95 0.30 2.98 0.00 2.98
Routing Flow Time (tL
) Runoff
23 23 17.2 -- -- -- -- 0.0 0.0 17.2 0.44 0.55 6.08 1.58 5.25 0.00 5.25
24 24 5.0 -- -- -- -- 0.0 0.0 5.0 0.65 0.81 9.95 0.18 1.43 0.00 1.43
25 25 5.0 -- -- -- -- 0.0 0.0 5.0 0.57 0.72 9.95 0.82 5.86 0.00 5.86
26 26 5.5 -- -- -- -- 0.0 0.0 5.5 0.41 0.51 9.63 0.24 1.15 0.00 1.15
27 27 5.0 -- -- -- -- 0.0 0.0 5.0 0.78 0.98 9.95 0.63 6.16 0.00 6.16
28 28 5.0 -- -- -- -- 0.0 0.0 5.0 0.77 0.96 9.95 0.34 3.26 0.00 3.26
29 29 9.8 -- -- -- -- 0.0 0.0 9.8 0.28 0.35 7.80 1.82 5.03 0.00 5.03
OS1 OS1 16.6 -- -- -- -- 0.0 0.0 16.6 0.63 0.79 6.20 3.80 18.49 0.00 18.49
Routing
1 1 5.0 -- 0.0 5.0 0.86 1.00 9.95 0.39 3.84 0.00 3.84
2 1,2 5.0 132.0 PA 0.4 1.2 1.8 6.8 0.79 0.98 8.96 0.84 7.40 0.00 7.40
3 1,2,3 6.8 58.0 PA 0.4 1.2 0.8 7.7 0.77 0.97 8.59 1.08 8.98 0.00 8.98
MH 1-5 7.7 113.0 PA 0.4 1.2 1.6 9.2 0.69 0.86 7.97 2.50 17.07 0.00 17.07
MH 1-5 9.2 271.0 PA 0.4 1.2 3.8 13.0 0.69 0.86 6.92 2.50 14.81 0.00 14.81
6 6 5.0 -- 0.0 5.0 0.66 0.82 9.95 0.27 2.18 0.00 2.18
7 6,7 5.0 44.0 PA 0.4 1.2 0.6 5.6 0.76 0.95 9.59 0.67 6.10 0.00 6.10
8 6-8 5.6 0.0 PA 0.4 1.2 0.0 5.6 0.77 0.96 9.59 0.93 8.55 0.00 8.55
9 6-9 5.6 150.0 PA 0.4 1.2 2.1 7.7 0.79 0.99 8.57 1.55 13.18 0.00 13.18
11 6-11 7.7 61.0 PA 0.4 1.2 0.9 8.6 0.79 0.99 8.22 2.25 18.39 0.00 18.39
Design Point Basins tc
Length Type Slope Velocity Travel
Pipe
Travel tc'
C C*Cf
Intensity Area
Direct
Runoff
Other
Runoff
Total
Runoff
Location (min) (ft) (a) (%) (ft/s) (min) (min) (min) (in/hr) (ac) (cfs) (cfs) (cfs)
Routing Flow Time (tL
) Runoff
22 22 5.0 -- 0.0 5.0 0.83 1.00 9.95 0.30 2.98 0.00 2.98
22 16-22 7.9 173.0 PA 0.4 1.2 2.4 10.3 0.77 0.96 7.62 3.56 26.17 0.00 26.17
MH 16-22 10.3 62.0 PA 0.4 1.2 0.9 11.2 0.77 0.96 7.37 3.56 25.31 0.00 25.31
23 23 17.2 -- 0.0 17.2 0.44 0.55 6.08 1.58 5.25 0.00 5.25
MH 23 17.2 201.0 PA 0.4 1.2 2.8 20.0 0.44 0.55 5.60 1.58 4.83 0.00 4.83
MH 16-23 20.0 146.0 PA 0.4 1.2 2.0 22.0 0.67 0.84 5.32 5.15 22.86 0.00 22.86
24 24 5.0 0.0 5.0 0.65 0.81 9.95 0.18 1.43 0.00 1.43
26 24-26 5.0 139.0 PA 0.4 1.2 1.9 6.9 0.55 0.69 8.91 1.23 7.60 0.00 7.60
27 24-27 6.9 16.0 PA 0.4 1.2 0.2 7.2 0.63 0.79 8.81 1.87 12.96 0.00 12.96
MH 16-27 22.0 -- 0.0 22.0 0.66 0.82 5.32 7.01 30.69 0.00 30.69
28 16-28 22.0 5.0 PA 0.4 1.2 0.1 22.1 0.66 0.83 5.31 7.35 32.37 0.00 32.37
29 16-29 22.1 33.0 PA 0.4 1.2 0.5 22.6 0.59 0.73 5.25 9.18 35.41 0.00 35.41
ALL 1-29 22.6 22.6 0.57 0.72 5.25 17.74 66.87 0.00 66.87
Note:
a) Codes the channel type for velocity calculations.
PA = Paved, PL = Pasture & Lawns, GW = Grassed Waterway
ASPEN ENGINEERING
9:08 AM
4/19/2017
25
POND SIZING
31
LID Summary
Lakeview on the Rise, Fort Collins, Colorado 801-002
New Area (Entire Site) 772,830 sf
Site Imperivious Area 371,148
Reqd. Min. Impervious Area to be Treated (75% of Total ImperviousArea) 278,361 sf
Area Treated by LID Treatment Method #1 (RAIN GARDEN) (Basin 1-15) 171,054 sf
Area Treated by LID Treatment Method #1 (RAIN GARDEN) (Basin 16-29) 200,094 sf
Total Impervious Area Treated 371,148 sf
Percent LID Treatment Provided for Impervious Site Area 100%
LID TABLE
Sheet 1 of 2
Designer:
Company:
Date:
Project:
Location:
1. Basin Storage Volume
A) Effective Imperviousness of Tributary Area, Ia Ia = 47.0 %
(100% if all paved and roofed areas upstream of rain garden)
B) Tributary Area's Imperviousness Ratio (i = Ia/100) i = 0.470
C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.16 watershed inches
(WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i)
D) Contributing Watershed Area (including rain garden area) Area = 373,118 sq ft
E) Water Quality Capture Volume (WQCV) Design Volume VWQCV = 4,930 cu ft
Vol = (WQCV / 12) * Area
F) For Watersheds Outside of the Denver Region, Depth of d6 = 0.00 in
Average Runoff Producing Storm
G) For Watersheds Outside of the Denver Region, VWQCV OTHER = 0.0 cu ft
Water Quality Capture Volume (WQCV) Design Volume
H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER = cu ft
(Only if a different WQCV Design Volume is desired)
2. Basin Geometry
A) WQCV Depth (12-inch maximum) DWQCV = 12 in
B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical) Z = 4.00 ft / ft
(Use "0" if rain garden has vertical walls)
C) Mimimum Flat Surface Area AMin = 3287 sq ft
D) Actual Flat Surface Area AActual = 3466 sq ft
E) Area at Design Depth (Top Surface Area) ATop = 7488 sq ft
F) Rain Garden Total Volume VT= 5,477 cu ft
(VT= ((ATop + AActual) / 2) * Depth)
3. Growing Media
(SEE LANDSCAPE PLANS AND CIVIL PLANS)
4. Underdrain System
A) Are underdrains provided?
B) Underdrain system orifice diameter for 12 hour drain time
i) Distance From Lowest Elevation of the Storage y = ft
Volume to the Center of the Orifice
ii) Volume to Drain in 12 Hours Vol12 = N/A cu ft
iii) Orifice Diameter, 3/8" Minimum DO = N/A in
Design Procedure Form: Rain Garden (RG)
AGW
ASPEN ENGINEERING
April 24, 2017
Lakeview on the Rise Pond 100
FORT COLLINS, CO
Choose One
Choose One
18" Rain Garden Growing Media
Other (Explain):
YES
NO
RainGardenSizing-LVOR-SW-Pond100, RG 4/24/2017, 7:38 PM
Sheet 2 of 2
Designer:
Company:
Date:
Project:
Location:
5. Impermeable Geomembrane Liner and Geotextile Separator Fabric
A) Is an impermeable liner provided due to proximity
of structures or groundwater contamination?
6. Inlet / Outlet Control
A) Inlet Control
7. Vegetation
8. Irrigation
A) Will the rain garden be irrigated?
Notes:
Design Procedure Form: Rain Garden (RG)
AGW
ASPEN ENGINEERING
April 24, 2017
Lakeview on the Rise Pond 100
FORT COLLINS, CO
Choose One
Choose One
Choose One
Sheet Flow- No Energy Dissipation Required
Concentrated Flow- Energy Dissipation Provided
Plantings
Seed (Plan for frequent weed control)
Sand Grown or Other High Infiltration Sod
Choose One
YES
NO
YES
NO
RainGardenSizing-LVOR-SW-Pond100, RG 4/24/2017, 7:38 PM
Sheet 1 of 2
Designer:
Company:
Date:
Project:
Location:
1. Basin Storage Volume
A) Effective Imperviousness of Tributary Area, Ia Ia = 51.0 %
(100% if all paved and roofed areas upstream of rain garden)
B) Tributary Area's Imperviousness Ratio (i = Ia/100) i = 0.510
C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.17 watershed inches
(WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i)
D) Contributing Watershed Area (including rain garden area) Area = 399,712 sq ft
E) Water Quality Capture Volume (WQCV) Design Volume VWQCV = 5,569 cu ft
Vol = (WQCV / 12) * Area
F) For Watersheds Outside of the Denver Region, Depth of d6 = 0.00 in
Average Runoff Producing Storm
G) For Watersheds Outside of the Denver Region, VWQCV OTHER = 0.0 cu ft
Water Quality Capture Volume (WQCV) Design Volume
H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER = cu ft
(Only if a different WQCV Design Volume is desired)
2. Basin Geometry
A) WQCV Depth (12-inch maximum) DWQCV = 12 in
B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical) Z = 4.00 ft / ft
(Use "0" if rain garden has vertical walls)
C) Mimimum Flat Surface Area AMin = 3713 sq ft
D) Actual Flat Surface Area AActual = 4600 sq ft
E) Area at Design Depth (Top Surface Area) ATop = 8390 sq ft
F) Rain Garden Total Volume VT= 6,495 cu ft
(VT= ((ATop + AActual) / 2) * Depth)
3. Growing Media
(SEE LANDSCAPE PLANS AND CIVIL PLANS)
4. Underdrain System
A) Are underdrains provided?
B) Underdrain system orifice diameter for 12 hour drain time
i) Distance From Lowest Elevation of the Storage y = ft
Volume to the Center of the Orifice
ii) Volume to Drain in 12 Hours Vol12 = N/A cu ft
iii) Orifice Diameter, 3/8" Minimum DO = N/A in
Design Procedure Form: Rain Garden (RG)
AGW
ASPEN ENGINEERING
April 24, 2017
Lakeview on the Rise Pond 200
FORT COLLINS, CO
Choose One
Choose One
18" Rain Garden Growing Media
Other (Explain):
YES
NO
RainGardenSizing-LVOR-SE-Pond200, RG 4/24/2017, 7:47 PM
Sheet 2 of 2
Designer:
Company:
Date:
Project:
Location:
5. Impermeable Geomembrane Liner and Geotextile Separator Fabric
A) Is an impermeable liner provided due to proximity
of structures or groundwater contamination?
6. Inlet / Outlet Control
A) Inlet Control
7. Vegetation
8. Irrigation
A) Will the rain garden be irrigated?
Notes:
Design Procedure Form: Rain Garden (RG)
AGW
ASPEN ENGINEERING
April 24, 2017
Lakeview on the Rise Pond 200
FORT COLLINS, CO
Choose One
Choose One
Choose One
Sheet Flow- No Energy Dissipation Required
Concentrated Flow- Energy Dissipation Provided
Plantings
Seed (Plan for frequent weed control)
Sand Grown or Other High Infiltration Sod
Choose One
YES
NO
YES
NO
RainGardenSizing-LVOR-SE-Pond200, RG 4/24/2017, 7:47 PM
22
APPENDIX C
23
STORM SEWER PIPE SIZING
(TO BE PROVIDED AT FINAL DESIGN)
Project Description
Friction Method Manning Formula
Solve For Full Flow Capacity
Input Data
Roughness Coefficient 0.013
Channel Slope 0.00400 ft/ft
Normal Depth 1.00 ft
Diameter 1.00 ft
Discharge 2.25 ft³/s
Results
Discharge 2.25 ft³/s
Normal Depth 1.00 ft
Flow Area 0.79 ft²
Wetted Perimeter 3.14 ft
Hydraulic Radius 0.25 ft
Top Width 0.00 ft
Critical Depth 0.64 ft
Percent Full 100.0 %
Critical Slope 0.00724 ft/ft
Velocity 2.87 ft/s
Velocity Head 0.13 ft
Specific Energy 1.13 ft
Froude Number 0.00
Maximum Discharge 2.42 ft³/s
Discharge Full 2.25 ft³/s
Slope Full 0.00400 ft/ft
Flow Type SubCritical
GVF Input Data
Downstream Depth 0.00 ft
Length 0.00 ft
Number Of Steps 0
GVF Output Data
Upstream Depth 0.00 ft
Profile Description
Profile Headloss 0.00 ft
Average End Depth Over Rise 0.00 %
12-in Pipe
2/13/2017 9:53:32 PM
Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 1 of 2
GVF Output Data
Normal Depth Over Rise 100.00 %
Downstream Velocity Infinity ft/s
Upstream Velocity Infinity ft/s
Normal Depth 1.00 ft
Critical Depth 0.64 ft
Channel Slope 0.00400 ft/ft
Critical Slope 0.00724 ft/ft
12-in Pipe
2/13/2017 9:53:32 PM
Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 2 of 2
Project Description
Friction Method Manning Formula
Solve For Full Flow Capacity
Input Data
Roughness Coefficient 0.013
Channel Slope 0.00400 ft/ft
Normal Depth 1.50 ft
Diameter 1.50 ft
Discharge 6.64 ft³/s
Results
Discharge 6.64 ft³/s
Normal Depth 1.50 ft
Flow Area 1.77 ft²
Wetted Perimeter 4.71 ft
Hydraulic Radius 0.38 ft
Top Width 0.00 ft
Critical Depth 1.00 ft
Percent Full 100.0 %
Critical Slope 0.00656 ft/ft
Velocity 3.76 ft/s
Velocity Head 0.22 ft
Specific Energy 1.72 ft
Froude Number 0.00
Maximum Discharge 7.15 ft³/s
Discharge Full 6.64 ft³/s
Slope Full 0.00400 ft/ft
Flow Type SubCritical
GVF Input Data
Downstream Depth 0.00 ft
Length 0.00 ft
Number Of Steps 0
GVF Output Data
Upstream Depth 0.00 ft
Profile Description
Profile Headloss 0.00 ft
Average End Depth Over Rise 0.00 %
18-in Pipe
2/13/2017 9:53:56 PM
Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 1 of 2
GVF Output Data
Normal Depth Over Rise 100.00 %
Downstream Velocity Infinity ft/s
Upstream Velocity Infinity ft/s
Normal Depth 1.50 ft
Critical Depth 1.00 ft
Channel Slope 0.00400 ft/ft
Critical Slope 0.00656 ft/ft
18-in Pipe
2/13/2017 9:53:56 PM
Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 2 of 2
Project Description
Friction Method Manning Formula
Solve For Full Flow Capacity
Input Data
Roughness Coefficient 0.013
Channel Slope 0.00400 ft/ft
Normal Depth 2.00 ft
Diameter 2.00 ft
Discharge 14.31 ft³/s
Results
Discharge 14.31 ft³/s
Normal Depth 2.00 ft
Flow Area 3.14 ft²
Wetted Perimeter 6.28 ft
Hydraulic Radius 0.50 ft
Top Width 0.00 ft
Critical Depth 1.36 ft
Percent Full 100.0 %
Critical Slope 0.00613 ft/ft
Velocity 4.55 ft/s
Velocity Head 0.32 ft
Specific Energy 2.32 ft
Froude Number 0.00
Maximum Discharge 15.39 ft³/s
Discharge Full 14.31 ft³/s
Slope Full 0.00400 ft/ft
Flow Type SubCritical
GVF Input Data
Downstream Depth 0.00 ft
Length 0.00 ft
Number Of Steps 0
GVF Output Data
Upstream Depth 0.00 ft
Profile Description
Profile Headloss 0.00 ft
Average End Depth Over Rise 0.00 %
24-in Pipe
2/13/2017 9:54:18 PM
Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 1 of 2
GVF Output Data
Normal Depth Over Rise 100.00 %
Downstream Velocity Infinity ft/s
Upstream Velocity Infinity ft/s
Normal Depth 2.00 ft
Critical Depth 1.36 ft
Channel Slope 0.00400 ft/ft
Critical Slope 0.00613 ft/ft
24-in Pipe
2/13/2017 9:54:18 PM
Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 2 of 2
Project Description
Friction Method Manning Formula
Solve For Full Flow Capacity
Input Data
Roughness Coefficient 0.013
Channel Slope 0.00400 ft/ft
Normal Depth 2.50 ft
Diameter 2.50 ft
Discharge 25.94 ft³/s
Results
Discharge 25.94 ft³/s
Normal Depth 2.50 ft
Flow Area 4.91 ft²
Wetted Perimeter 7.85 ft
Hydraulic Radius 0.63 ft
Top Width 0.00 ft
Critical Depth 1.74 ft
Percent Full 100.0 %
Critical Slope 0.00583 ft/ft
Velocity 5.28 ft/s
Velocity Head 0.43 ft
Specific Energy 2.93 ft
Froude Number 0.00
Maximum Discharge 27.90 ft³/s
Discharge Full 25.94 ft³/s
Slope Full 0.00400 ft/ft
Flow Type SubCritical
GVF Input Data
Downstream Depth 0.00 ft
Length 0.00 ft
Number Of Steps 0
GVF Output Data
Upstream Depth 0.00 ft
Profile Description
Profile Headloss 0.00 ft
Average End Depth Over Rise 0.00 %
30-in Pipe
2/13/2017 9:54:34 PM
Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 1 of 2
GVF Output Data
Normal Depth Over Rise 100.00 %
Downstream Velocity Infinity ft/s
Upstream Velocity Infinity ft/s
Normal Depth 2.50 ft
Critical Depth 1.74 ft
Channel Slope 0.00400 ft/ft
Critical Slope 0.00583 ft/ft
30-in Pipe
2/13/2017 9:54:34 PM
Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 2 of 2
Project Description
Friction Method Manning Formula
Solve For Full Flow Capacity
Input Data
Roughness Coefficient 0.013
Channel Slope 0.00400 ft/ft
Normal Depth 3.00 ft
Diameter 3.00 ft
Discharge 42.18 ft³/s
Results
Discharge 42.18 ft³/s
Normal Depth 3.00 ft
Flow Area 7.07 ft²
Wetted Perimeter 9.42 ft
Hydraulic Radius 0.75 ft
Top Width 0.00 ft
Critical Depth 2.12 ft
Percent Full 100.0 %
Critical Slope 0.00560 ft/ft
Velocity 5.97 ft/s
Velocity Head 0.55 ft
Specific Energy 3.55 ft
Froude Number 0.00
Maximum Discharge 45.37 ft³/s
Discharge Full 42.18 ft³/s
Slope Full 0.00400 ft/ft
Flow Type SubCritical
GVF Input Data
Downstream Depth 0.00 ft
Length 0.00 ft
Number Of Steps 0
GVF Output Data
Upstream Depth 0.00 ft
Profile Description
Profile Headloss 0.00 ft
Average End Depth Over Rise 0.00 %
36-in Pipe
2/13/2017 9:54:51 PM
Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 1 of 2
GVF Output Data
Normal Depth Over Rise 100.00 %
Downstream Velocity Infinity ft/s
Upstream Velocity Infinity ft/s
Normal Depth 3.00 ft
Critical Depth 2.12 ft
Channel Slope 0.00400 ft/ft
Critical Slope 0.00560 ft/ft
36-in Pipe
2/13/2017 9:54:51 PM
Bentley Systems, Inc. Haestad Methods Solution Bentley Center FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 2 of 2
24
APPENDIX D
25
*INLET, *CONCRETE SIDEWALK
CULVERT SIZING, PUBLIC
STREET CAPACITIES
(*TO BE PROVIDED AT FINAL DESIGN)
Major Storm
Design contraints:
Local: The depth of water over the crown shall not exceed 6 inches.
Arterial and Major Arterial: Depth of water not to exceed 6 inches above the crown or 18 inches above gutter flowline.
* Road width equals the width of pavement covered by water for one side of the road out from the edge of gutter pan.
Vertical Curb & Gutter
Design Point 3 4 5 13 27 28
Input
*Width of road section from edge of gutter pan (ft.): 16.00 16.00 16.00 16.00 16.00 16.00
Road elevation at end of road width (ft.): 0.41 0.41 0.41 0.41 0.41 0.41
Flood water elevation (ft.): 0.91 0.91 0.91 0.91 0.91 0.91
Gutter slope (ft/ft): 0.038 0.023 0.023 0.021 0.028 0.028
Cross slope of road (ft/ft): 0.02 0.02 0.02 0.02 0.02 0.02
Cross slope of sidewalk (ft/ft): 0.02 0.02 0.02 0.02 0.02 0.02
Sidewalk width (ft.): 4.50 4.50 4.50 4.50 4.50 4.50
Detachment width (ft.): 5.50 5.50 5.50 5.50 5.50 5.50
Cross slope of detachment (ft/ft): 0.02 0.02 0.02 0.02 0.02 0.02
Street Capacity
Computes flow capacities for a given section of Road
Lakeview on the Rise
801-002
Cross slope of detachment (ft/ft): 0.02 0.02 0.02 0.02 0.02 0.02
Cross slope behind back of walk (ft/ft): 0.02 0.02 0.02 0.02 0.02 0.02
Output
Check flood depth over gutter flowline (< 1.5 ft.) OK OK OK OK OK OK
Theoretical Capacity (cfs): 121.17 93.86 93.86 90.93 103.45 103.45
Theoretical Velocity (ft/s): 5.93 4.60 4.60 4.45 5.07 5.07
Reduction Factor: 0.62 0.78 0.78 0.79 0.74 0.74
Allowable Capacity (cfs): 75.71 73.36 73.36 72.09 76.20 76.20
Q100 2.17 4.82 4.31 4.03 6.16 3.26
Driveover Curb & Gutter
Design Point 3 4 5 13 27 28
Input
*Width of road section from edge of gutter pan (ft.): 16.00 16.00 16.00 16.00 16.00 16.00
Road elevation at end of road width (ft.): 2.00 2.00 2.00 2.00 2.00 2.00
Flood water elevation (ft.): 2.50 2.50 2.50 2.50 2.50 2.50
Gutter slope (ft/ft): 0.038 0.023 0.023 0.021 0.028 0.028
Cross slope of road (ft/ft): 0.02 0.02 0.02 0.02 0.02 0.02
Cross slope behind back of walk (decimal): 0.02 0.02 0.02 0.02 0.02 0.02
Output
Theoretical Capacity (cfs): 124.22 96.22 96.22 93.22 106.05 106.05
Theoretical Velocity (ft/s): 6.59 5.11 5.11 4.95 5.63 5.63
Reduction Factor: 0.62 0.78 0.78 0.79 0.74 0.74
Allowable Capacity (cfs): 77.61 75.20 75.20 73.90 78.12 78.12
Q100 2.17 4.82 4.31 4.03 6.16 3.26
ASPEN ENGINEERING
3:57 PM
4/5/2017
Minor Storm
Design constraints:
Local: No curb-topping. Flow may spread to crown of street.
Collector: No curb-topping. Flow spread must leave at least one lane width free of water.
Major Arteial: No curb-topping. Flow must leave at least 1/2 of roadway width free of water in each direction.
Vertical Curb & Gutter
Design Point 3 4 5 13 27 28
Input
Flood water elevation (ft.): 0.50 0.50 0.50 0.50 0.50 0.50
Gutter flowline elevation (ft.): 0.00 0.00 0.00 0.00 0.00 0.00
Cross slope of road (ft/ft): 0.02 0.02 0.02 0.02 0.02 0.02
Gutter slope (ft/ft): 0.038 0.023 0.023 0.021 0.028 0.028
Street Capacity
Computes flow capacities for a given section of Road
Lakeview on the Rise
801-002
Gutter slope (ft/ft): 0.038 0.023 0.023 0.021 0.028 0.028
Output
Lateral spread of water from edge of gutter pan: 16.50 16.50 16.50 16.50 16.50 16.50
Theoretical Capacity (cfs): 26.38 20.43 20.43 19.79 22.52 22.52
Theoretical Velocity (ft/s): 7.42 5.75 5.75 5.57 6.34 6.34
Reduction Factor: 0.62 0.78 0.78 0.79 0.74 0.74
Allowable Capacity (cfs): 16.48 15.97 15.97 15.69 16.59 16.59
Q2 0.50 0.99 0.99 0.92 1.41 0.75
Driveover Curb & Gutter
Design Point 3 4 5 13 27 28
Input
Flood water elevation (ft.): 0.39 0.39 0.39 0.39 0.39 0.39
Gutter flowline elevation (ft.): 0.00 0.00 0.00 0.00 0.00 0.00
Cross slope of road (ft/ft): 0.02 0.02 0.02 0.02 0.02 0.02
Gutter slope (ft/ft): 0.038 0.023 0.023 0.021 0.028 0.028
Output
Lateral spread of water from edge of gutter pan: 13.80 13.80 13.80 13.80 13.80 13.80
Theoretical Capacity (cfs): 16.56 12.83 12.83 12.43 14.14 14.14
Theoretical Velocity (ft/s): 6.44 4.99 4.99 4.83 5.50 5.50
Reduction Factor: 0.62 0.78 0.78 0.79 0.74 0.74
Allowable Capacity (cfs): 10.35 10.03 10.03 9.85 10.42 10.42
Q2 0.50 0.99 0.99 0.92 1.41 0.75
ASPEN ENGINEERING
3:56 PM
4/5/2017
26
APPENDIX E
27
SWALE SIZING
(TO BE PROVIDED AT FINAL DESIGN)
28
APPENDIX F
29
EROSION CONTROL & RIPRAP
SIZING & EROSION CONTROL
ESCROW ESTIMATE
(TO BE PROVIDED AT FINAL DESIGN)
30
APPENDIX G
31
PROPOSED & EXISTING DRAINAGE
BASIN EXHIBITS, EROSION
CONTROL PLAN, & EROSION
CONTROL NOTES AND DETAILS
SHEET
12 6-12 8.6 60.0 PA 0.4 1.2 0.8 9.4 0.80 1.00 7.92 2.47 19.48 0.00 19.48
MH 6-12 9.4 67.0 PA 0.4 1.2 0.9 10.3 0.80 1.00 7.61 2.47 18.74 0.00 18.74
13 1-13 5.0 -- 0.0 5.0 0.66 0.83 9.95 0.49 4.03 0.00 4.03
MH 1-13 13.0 89.0 PA 0.4 1.2 1.2 14.3 0.73 0.92 6.66 5.45 33.33 0.00 33.33
FES 1-13 14.3 57.0 PA 0.4 1.2 0.8 15.1 0.73 0.92 6.51 5.45 32.56 0.00 32.56
14 14 7.4 -- 0.0 7.4 0.26 0.32 8.70 0.46 1.27 0.00 1.27
15 1-15 15.1 -- 0.0 15.1 0.56 0.70 6.51 8.57 38.96 0.00 38.96
16 16 5.0 -- 0.0 5.0 0.77 0.96 9.95 1.03 9.77 0.00 9.77
17 16,17 5.0 177.0 PA 0.4 1.2 2.5 7.5 0.76 0.95 8.67 1.30 10.74 0.00 10.74
MH 16,17 7.5 31.0 PA 0.4 1.2 0.4 7.9 0.76 0.95 8.48 1.30 10.51 0.00 10.51
18 18 5.0 -- 0.0 5.0 0.85 1.00 9.95 0.46 4.57 0.00 4.57
19 18,19 5.0 29.0 PA 0.4 1.2 0.4 5.4 0.73 0.91 9.71 0.68 6.01 0.00 6.01
20 18-20 5.4 44.0 PA 0.4 1.2 0.6 6.0 0.74 0.92 9.37 1.32 11.40 0.00 11.40
21 18-21 6.0 86.0 PA 0.4 1.2 1.2 7.2 0.77 0.96 8.78 1.97 16.56 0.00 16.56
MH 18-21 7.2 18.0 PA 0.4 1.2 0.3 7.5 0.77 0.96 8.67 1.97 16.35 0.00 16.35
ASPEN ENGINEERING
9:08 AM
4/19/2017
MH 6-12 9.4 67.0 PA 0.4 1.2 0.9 10.3 0.80 2.18 2.47 4.29 0.00 4.29
13 1-13 5.0 -- 0.0 5.0 0.66 2.85 0.49 0.92 0.00 0.92
MH 1-13 13.0 89.0 PA 0.4 1.2 1.2 14.3 0.73 1.91 5.45 7.65 0.00 7.65
FES 1-13 14.3 57.0 PA 0.4 1.2 0.8 15.1 0.73 1.87 5.45 7.47 0.00 7.47
ASPEN ENGINEERING
9:09 AM
4/19/2017