HomeMy WebLinkAboutSite Certifications - 08/29/2018Mr. Wes Lamarque
City of Fort Collins Stormwater Utility
700 Wood St.
Fort Collins, CO
August 17, 2018
RE: Drainage Certification for West Plum Housing
Dear Mr. Lamarque,
This drainage certification letter is provided to verify as-constructed conditions for West Plum Housing.
Northern Engineering completed survey work August 9, 2018 to verify general compliance with the Final
Utility Plans for West Plum Housing, dated May 14, 2017 including revised drawings dated October 10,
2017 by Northern Engineering.
Included in this drainage certification submittal are the following:
Attachment 1 - City of Fort Collins Overall Site and Drainage Certification Form.
Attachment 2 - City of Fort Collins During Construction Inspection Checklist and photographs provided by
contractor.
Attachment 3 - As-constructed sand filter and detention vault calculations.
Attachment 4 - As-constructed record drawings for Grading and Storm Drain Plan and Profile Sheets.
Based on the calculations shown in Attachment 3, the as-built sand filter volumes are in Table 1. The as-
built sand filter will provide water quality and detention treatment within the site.
Table 1: Pond Record Volumes
Pond Design Water Vol. (ft3) As-built Water Vol. (ft3)
Detention Vault 3,067 5,149
We have concluded, based on the attached information and personal site inspection, that the drainage
features for the project site have been constructed in substantial compliance with the above referenced Final
Utility Plans, with the following exceptions:
• Item I.A: The sand filter and detention vault were constructed as part of the parking garage. The
dimensions and depths of the vault are per the approved design drawings.
• Item I.B: The sand filter and detention vault were constructed as part of the parking garage. The
dimensions and depths of the vault are per the approved design drawings.
Accepted 8/29/2018 WL
• Item I.B.1.c: The swale along Plum Street was constructed with a slope below 1.2% to 1.5%. The
approved design drawings called for a slope of 1.5%. We have re-analyzed the hydraulics of this
swale for the 100-year storm at a slope of 1.2%, and it will safely convey the storm event (see Figure
1). Based on this analysis, we feel this will convey the design storm hydraulic capacity.
• Item III.B.2: Northern Engineering did not observe construction. Northern Engineering was unable
to verify the encasements and clearances of the storm drain lines.
• Item III.B.3: Northern Engineering did not observe construction. Northern Engineering was unable
to verify the specific joint types and construction methods for the storm drain lines.
• Item IV.A.2: The curb and gutter along Plum Street, from the sidewalk chase to the west end of the
access drive into the parking garage, was constructed with a flowline slope 0.25%. However, the
spot elevation at the west end of the access drive is within the 0.2’ of the design elevation.
Furthermore, the immediate downstream slope was constructed at 1.4%. There will be some ponding
of nuisance flows in this area, but the gutter will safely convey the Minor and Major storm events
along Plum Street.
• Item IV.A.2: The box concrete channel, from the outlet of the detention vault pipe to the sidewalk
culvert, was constructed with 0.10’ sump in the middle of the flowline. However, all spot elevations
within the channel are within 0.2’ of the design elevations. There will be some ponding of nuisance
flows in this area, but the channel will safely convey the Minor and Major storm events through the
channel and towards Plum Street.
• Item XIII.A.3: Onsite landscaping activities are completed for this site.
Please feel free to contact me with any questions you may have.
Thank you,
NORTHERN ENGINEERING
Frederick S. Wegert, PE
Project Engineer
Figure 1: Swale Along Plum Street
Attachment 1
8/16 Page 1
OVERALL SITE and DRAINAGE CERTIFICATION
Commercial, Multi-Family and Subdivision Certification Form and Checklist
Project Name:
Date:
Building Permit Numbers:
(Commercial or multi-family)
Per the requirement in Fort Collins Stormwater Criteria Manual (FCSCM) Volume 1, Section 6.11, please fill in
all applicable items in this Certification Form for Commercial, Multi-Family and Overall Single Family sites.
NOTE: several items must be verified during construction. A copy of the approved grading plan must be
submitted with the as-built grading plan. (As-built elevations must be written in red next to the approved
elevations.)
•Use “Yes” for items completed as described.
•Use “N/A” for items that are not applicable to the site being certified.
•If any blanks are “No,” attach an explanation referencing the item number below.
Attach an explanation or description of the as-built condition for any items listed or for anything not listed but
shown on the approved construction plans.
Provide an as-built redline or Mylar drawing with the following:
I.Water Quality and Quantity Detention Basin Certification - FCSCM Vol.2, Ch.10
For multiple detention basins on a site, provide the following for each basin separately:
A. Volume: As-built topographic verification is attached at 1-foot (or less) contour intervals and
volume verification calculations for the water quality capture volume and the 100-year detention storage
volume.
1. Detention basin topography was prepared by a professional land surveyor registered in the state
of Colorado.
2.Both proposed and as-built contours are shown on the same plan sheet (dashed lines for
proposed and solid lines for as-built).
3.All critical spot elevations as shown on the approved construction plans have been verified and
the as-built elevations are shown on the plan sheet.
4.Stage-storage-discharge tables are provided on a separate document.
5.Verification that designed drain time is in compliance with Colorado Revised Statute § 37-92-
602(8) is attached and has been uploaded to the Statewide Compliance Portal
(tinyurl.com/COCompliancePortal) for approval. Uploaded documents must include:
a.The cover sheet from the approved drainage report
b.The stamped certification page from the approved drainage report
c.As-built topographic survey
d.Stamped certification page from the Overall Site & Drainage Certification
e.PDF output from the Stormwater Detention and Infiltration Design Data Speadsheet
West Plum Housing
August 17, 2018
B1700704
Yes
Yes
N/A
N/A
Yes
Yes
8/16 Page 2
B.Water Quality and Quantity Detention Basin Grading: Attached is as-built verification that there is
a minimum 2% positive fall into the concrete trickle pans or flow-line(s) from all areas in the bottom of
the detention pond. If there is a “soft pan” in the flow-line, all areas still must meet the minimum 2%
grade requirement.
1.Low Flow: Choose one of the following detention basin low flow options as applicable:
a. Turf swale for low flow path in detention basin.
There is a minimum 2% grade in the flow-line(s) of the detention basin. The flattest as-built grade
is .
b.Concrete pan for low flow in detention basin.
There is a concrete pan installed that meets the grades as shown on the approved construction
plans. (Show as-built spot elevations.)
c.Soft pan for low flow in detention basin.
•Verify and document the soft pan material gradation, trench width and depth - to be verified
during construction by engineer. Picture documentation is preferred or engineer’s statement of
visual inspection and compliance. (Choose one below.)
o There is a soft pan with an underdrain installed that meets the design on the approved
construction plans. (Show the underdrain grades, bedding material, geotextile, spot elevations,
bends, cleanouts, etc.)
o There is soft pan installed without an underdrain but there is a type A or B soil. The soil
type must be documented by supplying verification from a registered professional geotechnical
engineer.
NOTE: Spot elevations are to be within 0.2 ft. +/-.
2. Side Slopes: The as-built side slopes of the detention basin have been calculated and are shown.
Indicate the side slope with an arrow and a numerical value (e.g., 6.25:1). The maximum slope allowed
is 4:1. Small areas of 3:1 may be acceptable, but slopes steeper than 3:1 must be stabilized or re-
graded. Provide documentation if a variance was granted for steeper slopes during the design process.
3.Spillway Certification: The following items must be field verified:
a.The location of the spillway is indicated on the as-built plan.
b.The width of the spillway is indicated on the as-built plan.
c.The elevation(s) of the spillway is shown on the as-built plan.
d.A concrete ribbon defines the location and grade of the spillway.
e.There is downstream scour protection in the spillway as per the construction plans. Indicate
type: (riprap size “D50” gradation and bedding type, geotextile, buried
riprap with inches of bury, etc.).
f.There are no obstructions in the spillway, such as trees, bushes, sidewalks, landscape
features, rocks, etc.
Yes
N/A
Yes
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
8/16 Page 3
4.Outlet Structure Certification
a.The orifice plate for the approved release rate is installed with the correct size and location of
the orifice.
b.The orifice plate for the water quality outlet is installed with the correct hole size, number of
rows and columns of holes.
c.The bottom hole on both the water quality and quantity outlets are at the bottom of the plate
so no water ponds in front of the plate.
d.The well screen is the correct material and is installed as shown on the construction plans.
e.100-year overflow grate elevation is . (Elev. A on detail D-46)
f.The top elevation of the water quality capture volume is . (Elev. B on detail
D-46)
g.Overflow grate is made of the correct material, has the correct bar spacing, is hinged at the
top and bolted at the bottom.
h.The bottom of the outlet box has no obstructions or misalignments that will cause it to retain
runoff water and is sloped at 2% towards outlet.
II.Channels/Swales - FCSCM Vol.1, Ch.7, Sect.3&4
A. Capacity: The as-built capacity of all the major channels and swales has been verified. They meet
or exceed capacity requirements shown in the approved drainage study for this project.
1.All swales are located within the drainage easements as shown on the construction plans.
2.Longitudinal slopes and side-slopes (cross-sections) have been verified. Design criteria requires
longitudinal slopes of 2% min. (on vegetated swales) and side-slopes no steeper than 4:1. If these
criteria are not met, the certification engineer will write a justification and propose mitigation for each
instance or have the issues corrected. If variances to these criteria have previously been approved and
are shown on the construction plans, no justification is needed.
3.As-built spot elevations on channels/swales are shown that correspond to spot elevations
shown on the approved construction plans.
4.All permanent erosion control measures are installed as shown on the approved construction
plans (e.g., drop structures, riprap, TRMs, etc.). (Include pictures and verification of the materials used
as part of this verification.)
5.All pans, curbs, storm pipes or other appurtenances appropriately tie into each other in the
system. (Pictures at tie-in points suggested.)
6.The minimum freeboard is provided for all channels and swales as shown on the approved
construction plans or as identified in the approved drainage study. (Show the freeboard provided on
the cross-sections as on the construction plan set or attached as separate documentation.)
7.The low flow portion of all channels or swales is clear of obstructions. (No landscaping, trees,
shrubs, sod, etc. infringe on the low flow portion of channels or swales.)
Yes
5036.07
5037.26
N/A
N/A
Yes
Yes
Yes
Yes
Yes
N/A
No
Yes
N/A
Yes
Yes
Yes
Yes
8/16 Page 4
III.Storm Pipes (aka storm drains) - FCSCM Vol.1, Ch.6, Sec. 4
A. Storm Drain Pipe Capacity: The as-built capacity of all pipes installed on this project has been
verified and meets or exceeds the capacity requirements shown in the approved drainage study for this
project.
1.All storm drain pipe sizes and materials have been verified and are in conformance with the
approved construction plans. (Indicate on the plan and profile sheets that they have been verified.)
Material and size substitutions must be approved prior to installation. If a pipe size or material was
changed during construction, the certification engineer must attach the approval documents or supply
them with this certification. Approval documents must include a calculation documenting the capacity
equivalency (equal or greater) of the substituted size.
2.The longitudinal slope of the pipe is as shown on the approved construction plans. The
acceptable minimum slope is 0.4%. All slopes flatter than the designed slope on the construction plans
must be justified with capacity calculations on an attached sheet.
3.The as-built invert elevations have been verified and are shown on the plan and profile sheets of
the approved construction plans.
B.Storm Drain Pipe Installation Requirements: All pipes are installed in accordance with the
approved construction plans.
1.The minimum cover requirements for all pipes have been met as shown on the approved
construction plans. These will be called out in critical locations.
2.All encasements and clearances as specified on the approved construction plans have been met.
3.Any specific joint types or construction methods specified on the approved construction plans
have been met. (List on a separate sheet and attach to this certification.)
IV.Concrete Pans - FCSCM Vol.1, Ch.7, Sec.4.1.3.4
A. Construction/Installation: All concrete pans have been constructed in accordance with the
approved construction plans.
1.The concrete pans are the correct size/width as shown on the approved construction plans.
2.The longitudinal slopes of the pans are as shown on the approved construction plans. The
certification engineer must justify or mitigate longitudinal slopes less than the minimum of 0.4% unless
a flatter slope was approved and is shown on the approved construction plans. Provide mitigation or
justification by separate document.
3.The cross-section of the pan is as shown on the construction plans. (Specifically, the pan cross-
section is “V” shaped and meets the side slope shown on the detail.)
4.The concrete pans are a minimum of 6 inches thick without reinforcement and a minimum of 4
inches thick with a minimum of 6X6-W14xW14 reinforcement per detail D20B and D20C. (Provide
documentation of the reinforcement used if different than shown on the details or on the approved
construction plans.)
5.The spot elevations shown on the concrete pan(s) have been verified and are shown on the as-
built drawings.
Yes
Yes
Yes
Yes
Yes
Yes
No
No
Yes
Yes
No
Yes
Yes
Yes
8/16 Page 5
V. Storm Drain Inlets - FCSCM Vol.1, Ch.6, Sec. 3
A. Construction/Installation: All storm drain inlets have been constructed in accordance with the
approved construction plans.
1.The size and type of inlets are consistent with the inlets shown on the approved construction
plan. Indicate by writing “Verified” on each inlet on the plan sheet or list on a separate document the
inlet number(s), type and size (length). If the inlet installed is other than the one on the approved
construction plan detail sheet, provide the name and source of the detail with justification for equal or
better capacity.
2.The size of the inlet opening is consistent with the approved detail. (Check height and width.)
3.The elevation of the grate (if applicable) is at the elevation shown on the street profile or as
indicated by a spot elevation on the construction plans.
4.The as-built invert elevations of all pipes entering and leaving the inlet are shown on the plan
and profile sheets within construction tolerance of 0.2 feet. If substantially different, provide
justification and capacity calculations to show the capacity is not affected or propose mitigation.
5.The as-built size of the inlet box is as shown on the construction plans or an explanation or
justification is attached.
6.All Type C, R, 13 and 16 inlet covers are stenciled or stamped with the following (or an
equivalent) designation: NO DUMPING – DRAINS TO POUDRE RIVER.
VI.Culverts - FCSCM Vol.2, Ch.9
A. Construction/Installation: All culverts have been constructed and/or installed in accordance with
the approved construction plans.
1.All culvert sizes have been verified as indicated on the as-built construction plans as correct.
2.The culvert material type for all culverts installed is as on the approved construction plans and is
indicated on the as-built plans.
3.The as-built invert “in and out” elevations have been verified and are indicated on the as-built
construction plans.
4.The culvert headwalls or wing walls have been installed as shown on the approved construction
plans. Headwalls or wing walls may be needed in the as-built conditions onsite if the slopes adjacent to
the culvert are greater than 4:1. Please note areas needing stabilization in the certification narrative.
An alternative to consider is a turf reinforcement mat (TRM).
VII.Sub-Drains
A. Construction/Installation: All sub-drains shown on the construction plans have been installed in
accordance with those plans. Sub-drains installed with the sanitary sewer are to be verified on the
sanitary sewer plan and profile sheets of the construction plans. (NOTE: Indicate any sub-drains installed
after the plans were approved on the as-built plans.)
1.The size of the sub-drains are as approved on the construction plans and are indicated on the as-
built plans.
2.The type of sub-drain, in particular the perforated and non-perforated sections of the drain, are
as indicated on the approved construction plans.
Yes
Yes
Yes
Yes
Yes
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
8/16 Page 6
3.The cover requirements per the construction plans are provided.
4.The cleanouts have been installed at the locations shown on the construction plans and are
accessible for cleaning. (Cleanouts can be buried a maximum of 6 inches deep with their locations
marked.)
5.The backfill materials for sub-drains are as shown on the approved construction plans. (This
includes the type, depth and width.)
6.The geo-textile liner completely wraps the sub-drain and the permeable backfill material unless
shown otherwise on the approved construction plans. (Sub-drain pipe wrapped in a sock filter material
is accepted only if approved prior to installation.)
VIII.Curb Cuts
A. Construction: All curb cut openings are constructed in accordance with the approved construction
plans.
1.The size (width) of the curb cut opening is as shown on the approved construction plans.
2.The curb cut openings tie into a downstream swale, pipe, or other appurtenances with a smooth
transition and there no obstructions such as riprap or sod impeding the flow downstream of the curb
cut.
IX.Sidewalk Culverts & Chases
A. Construction/Installation: All sidewalk culverts have been installed at the locations shown on the
approved construction plans.
1.The size (width and length) of the culverts are as shown on the approved construction plans.
2.The cover plate is a minimum 5/8-inch galvanized plate bolted to a galvanized angle iron per the
detail shown on the approved construction plans or per the City’s detail.
3.The sidewalk culvert invert “in and out” elevations have been verified and are indicated on the
as-built plans.
4.The sidewalk culvert opening is as shown on the approved construction plans or per the City’s
detail.
5.There is a smooth transition both on the inlet and outlet ends of the sidewalk culvert with no
obstructions such as riprap or sod impeding the flow into or out of the sidewalk culvert.
X. Site Grading
A. Construction: All common open spaces have been graded in accordance with the approved
construction plans.
1.The grading on all common open spaces bordering private lots has been verified as correct and
the as-built rear lot corner elevations have been shown on the as-built plans.
N/A
N/A
N/A
N/A
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
8/16 Page 7
2.The as-built contours for “overlot grading” are shown on the as-built construction plans for all
common open spaces, tracts, outlots, etc. If not in compliance, please attach a narrative describing the
situation for noncompliance and when it may be corrected. An escrow for overlot grading may be
required. (NOTE: Residential Lot Grading Certification is a separate process from this Overall Site
Certification. It is understood that residential lots will be brought to final grade once the foundation is
backfilled so they may be lower than the plan shows at this Overall Site Certification stage.)
3.All turf reinforcement mats (TRMs) have been installed as shown on the approved construction
plans and the slopes are stabilized.
XI.Riprap - FCSCM Vol.1, Ch.7, Sec.4.4.4.3
A. Construction: All riprap has been installed in the locations and sizes indicated on the approved
construction plans.
XII.Permanent Erosion Control Fabric - FCSCM Vol.1, Ch.7
A. Construction: All fabric has been installed in the locations and sizes indicated on the approved
construction plans.
1.All fabric was installed per the details on the approved construction plans.
XIII.Post-Construction Site Cleanup - FCSCM Vol.3, Ch.7
A. Construction: All construction debris and obstructions of any kind have been removed from
drainage paths.
1.All construction debris has been removed except in staging area(s).
2.All ruts have been smoothed out in all construction areas.
3.All areas needing reseeding have been identified and future stabilization goals have been
coordinated with the Erosion Control Inspector and in accordance with FCSCM Vol.2 Chapter 12. Note
the area needing stabilization in the narrative.
XIV.Certification of Other Permanent BMPs - FCSCM Vol.2, Ch.8, Sec.2 & FCSCM Vol.2, Ch.12
A.The construction of channel drop structures is in accordance with the approved plan both in
location, horizontal dimensions and cross-section.
XV.Certification of LID and Water Quality Facilities - FCSCM Vol.3, Ch.4
A.Attached are the During Construction Inspection Checklist for Low Impact Development (LID) and
other items to be verified during construction, along with pictures and other required documentation.
N/A
Yes
Yes
N/A
N/A
N/A
N/A
Yes
Yes
Yes
N/A
8/16 Page 8
XVI. Certification and Erosion Control Measures
A. All temporary erosion control measures shall be removed upon stabilization. If at the time of preparing
this certification there are any erosion control measures still remaining on the site, please note them in
the narrative and verify that they need to remain at this time. If in doubt as to the need for any control
measure, please consult with the Erosion Control Inspector at 970-221-6700.
XVII.Statement of Compliance
A. This certification is signed and stamped. By signing this form, the engineer(s) attests that he/she has
visited and observed the site, and to the best of his/her knowledge, the as-built conditions of the drainage
facilities are as described in the above form and in the enclosed as-built plans.
B.Failure to properly disclose all known information could result in the rejection of this certification and
prevent the release of any and all Stormwater Utility permit holds on Building Permits and/or Certificates
of Occupancy within this development.
XVIII.Signature and Stamp by a Colorado-Registered Professional Engineer
Engineer’s contact information:
Name:
Email:
Phone:
Company:
Address:
PE Stamp
Frederick S. Wegert
fred@northernengineering.com
(970) 568-5408
Northern Engineering
301 N. Howes Street, Suite 100
Fort Collins, Colorado 80521
8/17/18
Attachment 2
Attachment 3
Project:
Date:
Outlet Elevation:5036.09 3,067 ft3
Grate Elevation:5037.26 1,480 ft3
Crest of Pond Elev.:5040.01 5038.4
Maximum
Elevation
Minimum
Elevation cu. ft.acre ft cu. ft.acre ft
5036.1 N/A 0.0 0 0.0 0.00 0.0 0.00
5036.2 5036.1 1,339.2 0.1 87.0 0.00 87.0 0.00
5036.5 5036.2 1,339.2 0.3 375.0 0.01 462.0 0.01
5037.0 5036.5 1,339.2 0.5 669.6 0.02 1,131.6 0.03
5037.5 5037.0 1,339.2 0.5 669.6 0.02 1,801.2 0.04
5038.0 5037.5 1,339.2 0.5 669.6 0.02 2,470.8 0.06
5038.5 5038.0 1,339.2 0.5 669.6 0.02 3,140.4 0.07
5039.0 5038.5 1,339.2 0.5 669.6 0.02 3,810.0 0.09
5039.5 5039.0 1,339.2 0.5 669.6 0.02 4,479.6 0.10
5040.0 5039.5 1,339.2 0.5 669.6 0.02 5,149.2 0.12
Volume at Grate:
Project Number:
Project Location:
Calculations By:
Pond No.:
Detention Pond Stage Storage Curve
Contour Contour
Surface Area
(ft2)
Depth
Incremental Volume Cummalitive Volume
Pond Stage Storage Curve
1252-001
Fort Collins, Colorado
F. Wegert
Vault
Elev at Design Volume:
West Plum Housing
8/17/2018
Pond Outlet and Volume Data
Design Volume:
8/17/2018 9:19 AM D:\Projects\1252-001\Drainage\Detention\
1252-001_AB_Stage-Storage.xlsx\Pond
Attachment 4
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N: 127045.08
E: 188588.17
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N: 127156.75
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111.86 LF 8" PVC @ 0.50%
9.70 LF 8" PVC @ 2.00%
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E:188606.38 N:126964.67
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EXISTING
GROUND
PROPOSED
GROUND
PRIVATE STORM DRAIN
CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU
DIG, GRADE, OR EXCAVATE FOR THE MARKING OF
UNDERGROUND MEMBER UTILITIES.
CALL UTILITY NOTIFICATION CENTER OF
COLORADO
Know what'sbelow.
before you dig.Call
R
C301
PL
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4.14.17
EXISTING RIGHT OF WAY
EXISTING WATER MAIN
LEGEND:
NOTES:
1.THE SIZE, TYPE AND LOCATION OF ALL KNOWN UNDERGROUND UTILITIES ARE APPROXIMATE WHEN
SHOWN ON THESE DRAWINGS. IT SHALL BE THE RESPONSIBILITY OF THE CONTRACTOR TO VERIFY THE
EXISTENCE OF ALL UNDERGROUND UTILITIES IN THE AREA OF THE WORK. BEFORE COMMENCING NEW
CONSTRUCTION, THE CONTRACTOR SHALL BE RESPONSIBLE FOR LOCATING ALL UNDERGROUND
UTILITIES AND SHALL BE RESPONSIBLE FOR ALL UNKNOWN UNDERGROUND UTILITIES.
2.ALL WATER FITTINGS AND VALVES ARE ONLY GRAPHICALLY REPRESENTED AND ARE NOT TO SCALE.
3.UTILITY SERVICES ARE SHOWN IN A SCHEMATIC FASHION ONLY. EXACT LOCATIONS SHALL BE PER THE
REQUIREMENTS OF THE RESPECTIVE UTILITY PROVIDERS, AND ARE SUBJECT TO CHANGE IN THE
FIELD.
4.MAINTAIN 10' HORIZONTAL AND 18" VERTICAL MINIMUM SEPARATION BETWEEN ALL STORM DRAINS,
SANITARY SEWER MAINS, WATER MAINS AND SERVICES.
5.REFER TO THE PLAT FOR LOT AREAS, TRACT SIZES, EASEMENTS, LOT DIMENSIONS, UTILITY
EASEMENTS, OTHER EASEMENTS, AND OTHER SURVEY INFORMATION.
6.LIMITS OF STREET CUT ARE APPROXIMATE. FINAL LIMITS ARE TO BE DETERMINED IN THE FIELD BY THE
CITY ENGINEERING INSPECTOR. ALL REPAIRS TO BE IN ACCORDANCE WITH CITY STREET REPAIR
STANDARDS.
11.PIPE LENGTHS ARE CALCULATED FROM THE CENTER OF MANHOLES AND INLET BOX STRUCTURES.
SPECIFIED LENGTH OF PIPE INCLUDES THE LAYING LENGTH OF FLARED END SECTIONS.
12.ALL RCP SHALL BE CLASS III OR GREATER. PIPE MATERIAL, BEDDING, AND INSTALLATION WITHIN
PUBLIC RIGHTS-OF-WAY SHALL BE GOVERNED BY THE CITY OF FORT COLLINS. ALTERNATES (SUCH AS
ADS N-12 OR HP SANITITE) OUTSIDE OF THE R.O.W. SHALL BE APPROVED IN ADVANCE BY THE
ENGINEER. ALL JOINTS SHALL BE 'WATERTIGHT' USING APPROPRIATE GASKETS OR JOINT WRAPS (PER
ASTM C443/C877 FOR RCP AND PER ASTM F477 / D3212 FOR PLASTIC PIPE). STORM DRAINS SHOWN ON
THIS DRAWING AS POLYVINYL CHLORIDE (PVC) SHALL BE SDR-35 OR APPROVED EQUAL.
13.CONTRACTOR SHALL BE RESPONSIBLE FOR ANY NECESSARY FIELD LOCATES AND POTHOLING OF
SUBSURFACE UTILITIES. ENGINEER AND CITY SHALL BE NOTIFIED OF ANY POTENTIAL CONFLICTS.
W
G
T
E
EXISTING STORM SEWER
PROPOSED ELECTRIC
EXISTING TELEPHONE
EXISTING GAS
SPROPOSED SEWER SERVICE
FPROPOSED FIRE SERVICE
EXISTING SANITARY SEWER SS
PROPOSED FIRE DEPT. CONN.
PROPOSED CURB & GUTTER
PROPOSED CURB STOP & METER PIT
FDC
PROPOSED FIRE HYDRANT
EXISTING FIRE HYDRANT
PROPERTY BOUNDARY
EASEMENT LINE
FOEXISTING FIBER OPTICS
PROPOSED STORM SEWER
PROPOSED WATER MAIN
PROPOSED SANITARY SEWER
W
PROFILE SCALE:
DETENTION OUTFALL
NORTH
( IN FEET )
1 inch = ft.
Feet02020
20
40 60
RECORD DRAWING
C602
ST
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4.14.17
300 STORMWATER BEDDING 301 CURB, GUTTER AND SIDEWALK 302 METAL SIDEWALK CULVERT FOR VERT. CURB & GUTTER
AND DETACHED SIDEWALK-OUTFALL TO CURB
307
SECTION B-B
DETAIL 1
SECTION A-A
PLAN
SECTION C-C
CC
BB
A
A
CONCRETE SIDEWALK w/ PAN
CC
A
A
SECTION C-C
SECTION A-A
WELL SCREEN
PLAN
GENERAL NOTES
SECTION B-B
B
B
A A
ABBREVIATIONS
LEGEND
303 ORIFICE PLATE
ORIFICE OPENING
(6.25" Ø)
PLATE CENTERED
OVER PIPE OPENING
IN WALL
12" Ø HOLES FOR
3 8" Ø EXPANSION BOLTS
EMBEDDING 2" INTO
CONCRETE WALL @
6" O.C. MIN.
5 16" THICK
GALVANIZED
STEEL PLATE D
D+4"
D+4"
ORIFICE INVERT SHALL MATCH
PIPE INVERT
308 OUTLET STRUCTURE CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU
DIG, GRADE, OR EXCAVATE FOR THE MARKING OF
UNDERGROUND MEMBER UTILITIES.
CALL UTILITY NOTIFICATION CENTER OF
COLORADO
Know what'sbelow.
before you dig.Call
R
305 CONCRETE HEADWALL & CHASE
4'1'
1"
2.00%8.33%
6"
5036.13
5037.13
5038.13
N/A
4'
4'
12"
WAL
K
LAN
D
S
C
A
P
E
D
A
R
E
A
LAN
D
S
C
A
P
E
D
A
R
E
A
0.5
(
M
I
N
.
)
%
7'
8" PVC PIPE
(SEE PLANS)
6" T
Y
P
.
30" VERTICAL
CURB & GUTTER
2'
8"
±15"9.5
'
2' CHASE
(DETAIL D-10B)
0.5
(
M
I
N
.
)
%
LAN
D
S
C
A
P
E
D
A
R
E
A
LAN
D
S
C
A
P
E
D
A
R
E
A
12"
N/A
N/A
N/A
PAVING SECTIONS
(PRIVATE AREAS OUTSIDE ROW)306
SCREEN SLOT TABLE
A B C D E F
PIPE SIZE ROWS OF
SLOTS
SLOT
LENGTH
MAXIMUM
SLOT WIDTH
APPROX.
SLOT/ROW
PER FOOT
APPROX.
SLOT
SPACING
OPEN AREA
PER FOOT
6"3 (MIN.) - 6 (MAX.)1.38"-2.35"0.032"14 1/2"-3/4"1.98-3.15 SQ. IN.
PRIVATE UNDERDRAIN CLEANOUT
4" MIN
EXTEND MIN. 6" INTO SUBGRADE
6"
VARIES
(REFER TO
STORM DRAIN
PLAN)
INTEGRATED DUCTILE IRON
FRAME & SOLID GRATE TO MATCH
BASIN O.D.
NOTES:
1 - GRATES/SOLID COVERS SHALL BE DUCTILE IRON PER ASTM A536 GRADE
70-50-05
2 - FRAMES SHALL BE DUCTILE IRON PER ASTM A536 GRADE 70-50-05
3 - DRAIN BASIN TO BE CUSTOM MANUFACTURED ACCORDING TO PLAN DETAILS
SEE DRAWING NO. 7001-110-065
4 - PERFORATIONS SHOULD NOT BE ON OR WITHIN 1" OF ADAPTERS.
5 - HOLES SHOULD BE STAGGERED EVERY OTHER ROW, AS SHOWN.
6 - MIN. 90° SEPARATION BETWEEN HOLES (MAX. 4 HOLES PER ROW)
2" MIN
Ø .375" MAX
SIDE VIEW
HOLE SIZE & LOCATION NTS
ENLARGED TO SHOW DETAIL
6"THE BACKFILL MATERIAL SHALL BE CRUSHED STONE OR OTHER
GRANULAR MATERIAL MEETING THE REQUIREMENTS OF CLASS II
MATERIAL AS DEFINED IN ASTM D2321. BEDDING & BACKFILL FOR
SURFACE DRAINAGE INLETS SHALL BE PLACED & COMPACTED
UNIFORMLY IN ACCORDANCE WITH ASTM D2321.
TRAFFIC LOADS: CONCRETE SLAB DIMENSIONS ARE FOR GUIDELINE
PURPOSES ONLY. ACTUAL CONCRETE SLAB MUST BE DESIGNED
TAKING INTO CONSIDERATION LOCAL SOIL CONDITIONS, TRAFFIC
LOADING, & OTHER APPLICABLE DESIGN FACTORS.
TOP 10" TO BE SOLID, WITHOUT PERFORATIONS
10" SOLID
TOP
NO PERFORATIONS
WITHIN 1" OF ADAPTORS
OPEN BOTTOM
(NO BOTTOM CAP)
309
8" MIN. THICKNESS GUIDELINE
12" MIN WIDTH GUIDELINE
304
DIMENSIONS FOR SLOTTED
HDPE PIPE
5036.225036.28
5036.24
5036.31
5036.40
5036.44
1.0' DIA. HOLE WITH
FL AT 5037.61
49
.
6
'
8" CONCRETE
WALLS (TYP.)
POND
OUTLET
STRUCTURE