HomeMy WebLinkAboutSite Certifications - 10/12/20161501 Academy Ct. Suite 203 | Fort Collins, CO 80524 | 970-530-4044 | www.unitedcivil.com
September 30, 2016
Mr. Wes Lamarque
Stormwater Department
City of Fort Collins Utilities
700 Wood Street
Fort Collins, CO 80521
RE: Site Drainage Certification – Part 3
The Square – Phase 1
Fort Collins, CO
United Civil Project #U13011
This is the final part of the Site Drainage Certification for the drainage facilities shown on the
Utility Plans for The Square originally prepared on 3/11/2014 and amended on 11/5/2014,
12/11/2014, and 1/22/2015. Part 1 of this site drainage certification was completed on October
1, 2014 and was completed in association with the Certificate of Occupancy (C.O.) for Sierra
Trading Post (included as Appendix 3). Part 2 of this site drainage certification was completed
on February 20, 2015 and was completed in association with the C.O. for Trader Joe’s (included
as Appendix 4).
The purpose of this final part of the Site Drainage Certification is to document the construction
of the water quality pond on the east side of the site. It was decided to delay the construction
of the pond until the construction around it was complete in order to keep construction
sediment out of the bioretention facility. The Square Shopping Center owner posted security in
the amount of $28,517.25 for the future construction of the pond with Part 1 of the Site
Drainage Certification. It is understood that this certification and the City’s acceptance of the
pond improvements will release those funds back to the owner.
As discussed above, this portion of the site drainage certification only applies to the water
quality pond on the east side of the site. The area of certification is highlighted on the original
drainage plan which is attached as Exhibit A. This water quality pond was modified as part of
the Phase 3 construction plans that were included with Minor Amendment #150084. These plan
sheets from the Phase 3 construction plans show the water quality pond that is included with
this Certification. The remainder of the Phase 3 plans and the Phase 2 plans (Minor Amendment
#150045) are not part of this Site Drainage Certification.
There are a few items to note about the construction of the water quality pond:
The invert of the 30” outlet pipe was 0.4’ lower than expected. Since the outlet box
was pre-cast, this lowered the overflow elevation at the top of the box by 0.4’.
Since this was the case, we lowered all of the layers in the bioretention pond 0.4’ to
maintain the effective volume in the pond.
Since the top of the bioretention material was 0.4’, the 4:1 side slopes extended
further into the pond. This reduced the volume slightly, but it was decided in
conjunction with City staff that this would be better than having steeper side slopes.
Wes Lamarque
10/12/2016
1501 Academy Ct. Suite 203 | FORT COLLINS, CO 80524 | 970-530-4044 | www.unitedcivil.com
The conditions at the bottom of the bioretention pond were pretty wet due to rain
and other water sources. This combined with the near vertical walls on the side of
the pond made it impossible to excavate the entire pond at once. The contractor
excavated sections of the pond and backfilled them with gravel to limit the amount
of the excavation that was open at one time.
The as-builts for the detention pond have been included in Appendix 1.
The as-built volume of the detention pond is 9,733 cf, compared to a required
volume of 9,726 cf.
The original drainage certification form that was used in Part 1 and Part 2 has been
updated to include the construction of the water quality pond. In addition, the
city’s new “During Construction Inspection Checklist” for Bioretention Cells has been
included. These are both included in Appendix 1.
United Civil Staff made 24 site visits between 5/26/16 and 9/23/16 to witness,
document, and assess the progress of construction of the water quality pond. Some
of the photographs have been included in Appendix 2.
If you have any questions, please contact me at 970-530-4044, or sam.eliason@unitedcivil.com.
Sincerely,
United Civil Design Group, LLC
Sam Eliason, P.E.
Enclosures:
Appendix 1
Drainage Certification Form (5 pages)
Bioretention Cells Checklist
Exhibit A: Drainage Plan with Site Drainage Certification Area shown
Exhibit B: As-Built Water Quality Pond Plan
Exhibit C: As-Built Water Quality Pond Section
Exhibit D: Approved Plans (Sheets C2.02, C5.00, C6.00, and C8.02)
Appendix 2 – Water Quality Pond Construction Photos
Appendix 3 – Site Drainage Certification – Part 1 – October 1, 2014
Appendix 4 – Site Drainage Certification – Part 2 – February 20, 2015
APPENDIX 1
•Drainage Certification Form
•Bioretention Cells Checklist
•Exhibit A – Drainage Plan with Site Drainage Certification
Areas shown
•Exhibit B – As-Built Water Quality Pond Plan
•Exhibit C – As-Built Water Quality Pond Section
•Exhibit D – Approved Plans (Sheets C2.02, C5.00, C6.00 and
C8.02)
DRAINAGE CERTIFICATION FORM
Please fill out all applicable items in this certification form for
single family, multi-family and commercial properties.
Write “OK” for items checked or actual number checked in field.
Use “N/A” for items that are not applicable to the property that is
being certified.
A. Drainage facilities certification
1. Pond Certification
-volume verification
a.topographic records and volume
b.cross-sections and spot elevations
-positive fall to pan
-side slopes
-invert elevation
-spillway elevation
-placement and size of riprap
--- grading
-orifice plate installation and size_
-compaction of berm
-structural integrity of pond
2. Swales
-location (are they within easement)
-dimensions and cross-section verification
-longitudinal slopes and side slopes
-spot elevations
-permanent erosion control measures (drop structures, riprap,
etc....)
-tie-in to pipes, pans, curbs, etc....
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
_
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
-weir size (elevations, size, opening, etc.)
-available freeboard
-landscaping infringement on swales
3. Pipes
-size and type
-slopes (as-built and comparison to minimum 0.4% slope)
-pipe capacity calculations if slopes are significantly
altered
-invert elevations
-installation and backfill material
-cover
-encasement and clearance from other utility lines close by
-joints
4. Concrete Pan Channels
-size
-slope
-super elevation
-cross - section
-thickness
-elevations
5. Inlets
-size and type
-size of opening (or name of standard used)
-grate elevation
-invert elevation
-box size
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
Okay per Sailer Construction
Okay per Sailer
Okay per Sailer Construction
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
6. Cross pans
-size
-type
-grade
-elevation
-cross-sectional depth
-tie-in to curb and gutter
7. Culverts
-size
-type
-invert elevation
-headwalls
8. Underdrains
-size
-type
-cover
-backfill
-geotextiles
-cleanouts
9. Curb cuts
-size
-tie in to swale, pipe, etc...
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
B. Certification of Grade Elevations Adjacent to Drainage
Facilities:
-minimum opening elevations
-top of foundation elevations
-comparison to 100 year WSEL’s (Freeboard requirements and
floodplain issues)
C. Certification of Erosion Control Measures:
1. Permanent Measures:
-Permanent vegetation (6” bare spots and weeds under control)
-riprap
-riprap bedding
-drop sections
-sediment basins/water quality ponds
-netting mats/blankets
-mulching
2. Temporary Measures:
-mulching
-inlet filter installation
-check bale dams
-seeding and temporary vegetation
-silt fence
D. Site Cleanup After Construction
-construction clean up
-smoothing of ruts
-reseeding
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
E. Statement of Compliance
This certification is signed and stamped and by signing this
form the engineer(s) attests that they have inspected the site and
to the best of their knowledge the as-built conditions of the
drainage facilities are as described in the above form and in the
redlined plans enclosed.
Failure to properly disclose all known information could result
in the rejection of this certification and prevent the release of
any Stormwater Utility holds on Building Permits and/or Certificates
of Occupancy.
F. Signature and Stamp by a Colorado Registered Professional
Engineer.
Samuel M. Eliason
Colorado Licensed Professional Engineer
CO P.E. # 38212
12/15 Page 3
Bioretention Cells
Item/Activity Yes No N/A Documentation/Submittal Requirements
Excavation
Heavy equipment did not travel over bioretention cell during
excavation
Bottom of cell was “ripped” after excavation Photograph before/after “ripping”
Bottom of cell is flat and level Photograph
Excavated area is protected/surrounded by sediment/runoff
control BMPs during construction
Photograph
Inlet
Overflow inlet elevation is set above bioretention media per
plan (typically 12 inches)
Overflow inlet invert elevation is at least 3 inches below
containment wall/berm (to direct overflow into inlet)
Measure/record distance between inlet and top of
containment wall/berm
Upstream catchment drains to inlet
Forebay
Forebay is installed according to design specifications
Forebay has flat, concrete bottom
Outlet Structure/Overflow
Outlet structure/overflow elevation is confirmed Measure/record distance from overflow to top of media
filter
Impermeable Liner
Impermeable liner meets design specifications
Impermeable liner attached to concrete perimeter wall
Impermeable liner is not exposed
Underdrain System
Underdrain pipe is per design specifications
At least one cleanout is provided per underdrain lateral
Cleanout pipe is not perforated
Cleanout covers are installed and watertight
Underdrain is NOT wrapped in geotextile fabric
Underdrain orifice plate installed at outlet structure
Underdrain integrity tested after backfilling using TV and/or
water test
(Approximately 14.5")
(Approximately 8")
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
12/15 Page 4
Filter Media
Filter media composition is per design specifications
Filter media was “machine mixed” by supplier prior to delivery
Filter media installed flat and level
Other Structural Components
Containment wall/berm is continuous and level
Landscaping
Final landscaping does NOT include sod
Final landscaping (wood/rock mulch) is flat and level
Vegetation is planted according to landscape design
specifications
Verify that weed barrier is not installed
Temporary irrigation installed If N/A, then verify that permanent irrigation is installed to
establish/maintain vegetation
Close Out
Upstream catchment stabilized prior to diverting runoff into
bioretention cell
Signature:
Name:
Title:
Email:
Phone:
Company:
Address:
4
4
4
4
4
4
4
4
4
4
Samuel M.Eliason
Principal
sam.eliason@unitedcivil.com
970-530-4044
United Civil Design Group
1501 Academy Ct.Ste 203
Fort Collins,CO 80524
EXHIBIT A
PART 2
PART 1
PART 3
POROUS BIORETENTION
(SEE DETAILS)
PROPOSED OUTLET
STRUCTURE AT 11.90
FOREBAY
12" CONCRETE
STRIP W/ 4"
PEA GRAVEL
BOTTOM OF POND
(MIN ELEV = 10.64,
(MAX ELEV = 10.75)
LIMITS OF BIORETENTION
SECTION AT THE HDPE
MEMBRANE (2713 SF)
CLEANOUT (TYP.)
(1 OF 4)
6" PVC UNDERDRAIN PIPE
6" PVC UNDERDRAIN PIPE
AS PROPOSED CONTOUR
AS-BUILT CONTOUR
AS PROPOSED SPOT ELEVATION
AS-BUILT SPOT ELEVATION
AS-BUILT SLOPE
0 10'20'
SCALE: 1" = 10'
5'
LEGEND
NOTES
1.AS-BUILT SPOT ELEVATIONS AND CONTOURS PER SURVEY
PERFORMED BY PLS GROUP, INC. ON 9/26/2016.
2.AS-PROPOSED SPOT ELEVATIONS AND CONTOURS PER THE
SQUARE SHOPPING CENTER UTILITY PLANS FOR MINOR
AMENDMENT #150084 (PHASE 3) SHEET C5.0 AS PREPARED
BY UNITED CIVIL DESIGN GROUP ON 6/17/2016
THE SQUARE
9/30/2016
EXHIBIT B - AS-BUILT WATER QUALITY POND PLAN
EXISTING
GROUND
PROPOSED
GROUND
14.5"
PONDING
MINIMUM 30-MIL
HDPE IMPERVIOUS
MEMBRANE
MINIMUM 12" THICK
BIORETENTION SAND MEDIA
LAYER (SEE NOTES 1-2)
MINIMUM 6" THICK
PEA GRAVEL LAYER
CDOT AGGREGATE NO. 4
STORAGE/ FILTRATION LAYER
PIPE P2 & P3
4" PERFORATED
UNDERDRAIN
INV. 5004.10 (N&S-
MATCH EXISTING)
PIPE E1
EXISTING 30" RCP
STORM DRAIN
OUTLET STRUCTURE
(SEE DETAIL)
MINIMUM 30-MIL
HDPE IMPERVIOUS
MEMBRANE
UNDISTURBED
EARTH
UT
I
L
I
T
Y
E
A
S
E
M
E
N
T
PR
O
P
E
R
T
Y
L
I
N
E
INV. 5004.00
(EXISTING)
GRATE 5011.90
TO
P
O
F
B
E
R
M
5
0
1
2
.
7
5
PHASE 3 CURB
AND GUTTER
12" WIDE BY 4" DEEP
CONCRETE
4" PEA GRAVEL
FOREBAY TO
CAPTURE INITIAL
SEDIMENT
ELEV. 5003.80
ELEV. 5009.70
ELEV. 5009.20
ELEV. 5010.70
EXISTING MANHOLE
PIPE P4 & P5
6" PERFORATED
UNDERDRAIN
INV. OUT 5007.5 (N&S)
PIPE E3
EXISTING 8" PVC
INV. 5007.99
INV. 5004.42
(EXISTING)
PLUG EXISTING 30"
RCP (SEE NOTE 3)
PIPE P1
18" HDPE
INV. 5006.23
PIPE E2
18" HDPE
INV. 5005.75
12" CDOT NO. 4 AT
BASE OF INLET
DRILL 12 1" HOLES IN INLET.
(6 ON NORTH SIDE AND 6 ON
SOUTH SIDE. 3 AT 4" AND 3
AT 18" ABOVE BOTTOM)
EXISTING INLET
TO REMAIN
1
C8.02 NOT TO SCALE
NOTES:
1.REFER TO THE CITY OF FORT COLLINS BIORETENTION SAND MEDIA SPECIFICATION FOR MORE
INFORMATION ON THE SOIL MIX.
2.BIORETENTION SAND MEDIA SHALL BE PROVIDED BY HAGEMAN EARTH CYCLE OR APPROVED EQUAL.
3.PIPE TO BE PLUGGED WITH PRE-MANUFACTURED CAST-ALUMINUM EXPANSION PLUG OR METAL
PLATE ATTACHED TO THE OPENING. IN THIS PARTICULAR CASE, THE PLUG DOES NOT NEED TO BE
WATER TIGHT, BUT SHOULD BE SOIL TIGHT.
4.REFER TO SHEET C2.02 FOR A PLAN VIEW OF STORM INFRASTRUCTURE.
Water
Quality
Storage
(cf)
Detention
Storage
(cf)
Total
Volume
(cf)
Top
Elevation
Outfall
Elevation
Total
Provided 9,733 9,733 9,733 5011.90 5004.00
Total
Required 9,193 9,726 9,726
* POND VOLUME PROVIDED INCLUDES 1,312 CF OF SURFACE STORAGE AND
8,421 CF OF SUBSURFACE STORAGE.
**SUBSURFACE VOLUME BASED ON 2,625 SQUARE FEET OF BIORETENTION
AREA AND A 45% VOID RATIO.
THE SQUARE
9/30/2016
EXHIBIT C - AS-BUILT WATER QUALITY POND POND SECTION
APPENDIX 2
Water Quality Pond Construction Photos
1501 Academy Ct. Suite 203 | Fort Collins, CO 80524 | 970-530-4044 | www.unitedcivil.com
Water Quality Pond Construction Photos – 5/26/2016 to 9/23/2016
Picture 1: Excavation of Bioretention Pond with Erosion Control in place
Picture 2: More Excavation of Bioretention Pond
1501 Academy Ct. Suite 203 | FORT COLLINS, CO 80524 | 970-530-4044 | www.unitedcivil.com
Picture 3: CDOT #4 in place with first underdrain and cleanout
Picture 4: Second underdrain in place
1501 Academy Ct. Suite 203 | FORT COLLINS, CO 80524 | 970-530-4044 | www.unitedcivil.com
Picture 5: Placement of CDOT #4 and underdrain
Picture 6: Placement of CDOT #4 and underdrain cleanout
1501 Academy Ct. Suite 203 | FORT COLLINS, CO 80524 | 970-530-4044 | www.unitedcivil.com
Picture 7: Level CDOT #4 and addition of 6” of pea gravel
Picture 8: 6” of Pea Gravel over CDOT #4
1501 Academy Ct. Suite 203 | FORT COLLINS, CO 80524 | 970-530-4044 | www.unitedcivil.com
Picture 9: Level Pea Gravel
Picture 10: 12” of Bioretention material added
1501 Academy Ct. Suite 203 | FORT COLLINS, CO 80524 | 970-530-4044 | www.unitedcivil.com
Picture 11: 12” of bioretention throughout pond. Side slope added (too steep)
Picture 12: 12” of Bioretention material added throughout pond.
1501 Academy Ct. Suite 203 | FORT COLLINS, CO 80524 | 970-530-4044 | www.unitedcivil.com
Picture 13: Side slope flattened.
Picture 14: Final landscaping of pond
1501 Academy Ct. Suite 203 | FORT COLLINS, CO 80524 | 970-530-4044 | www.unitedcivil.com
Picture 15: Final landscaping of pond
Picture 16: Final landscaping of pond and outlet structure
1501 Academy Ct. Suite 203 | FORT COLLINS, CO 80524 | 970-530-4044 | www.unitedcivil.com
Picture 17: Final landscaping of pond
Picture 18: Final landscaping of pond
APPENDIX 3
Site Drainage Certification – Part 1
October 1, 2014
1501 Academy Ct. Suite 203 | Fort Collins, CO 80524 | 970-530-4044 | www.unitedcivil.com
October 1, 2014
Mr. Wes Lamarque
Stormwater Department
City of Fort Collins Utilities
700 Wood Street
Fort Collins, CO 80521
RE: Site Drainage Certification – Part 1
The Square
Fort Collins, CO
United Civil Project #U13011
On September 29th, United Civil Design Group, LLC personnel conducted a site visit at the The
Square redevelopment project, located in Fort Collins, CO. The purpose of the site visit was to
verify and document the drainage facilities shown on the Utility Plans for The Square prepared
by United Civil Design Group on 3/11/2014.
This site drainage certification only applies to the south half of the site that is usable to Sierra
Trading Post. The owner is only requesting a CO for Sierra Trading Post at this time. The
northern portion of the site, which includes the construction of Trader Joe’s, is still under
construction. The area of certification is highlighted on the original drainage plan which is
attached as Exhibit A.
In addition, the site drainage certification does not include the water quality pond on the east
side of the site. It was decided to delay construction on that pond until the end of construction
in order to keep construction sediment out of the bioretention facility. A cost estimate for the
construction of this facility is attached as Exhibit B. The owner will put up security for the future
construction of the pond.
There are a couple of minor items that the developer has been made aware of and will be fixing
this week. These items include:
• Construction of curb cut on the southeast corner of the southern parking lot.
• Final landscaping and site construction cleanup
There were a few drainage related items that changed during the construction that should be
noted.
• All of the existing parking lots were overlaid so most of the grades shown in the
parking lot were changed up to 2” to reflect the overlay. This did not affect the sites
ability to drain effectively.
• There were a number of roof drains that were added to tie into the existing storm
sewer on the south side of the building. The water from these roofs drained to the
existing storm system via overland flow previously so there was no change to the
existing drainage patterns on the site.
1501 Academy Ct. Suite 203 | FORT COLLINS, CO 80524 | 970-530-4044 | www.unitedcivil.com
Please note that United Civil personnel were not on site to witness the actual construction of
the infrastructure while it was being installed. However, the contractor has verified that
construction of the storm sewer and concrete pans throughout the site were in conformance to
the plans.
If you have any questions, please contact me at 970-530-4044, or sam.eliason@unitedcivil.com.
Sincerely,
United Civil Design Group, LLC
Sam Eliason, P.E.
Enclosures:
• Drainage Certification Form (5 pages)
• Exhibit A: Drainage Plan with Site Drainage Certification Area shown
• Exhibit B: Water Quality Pond Cost Estimate for Escrow
DRAINAGE CERTIFICATION FORM
Please fill out all applicable items in this certification form for
single family, multi-family and commercial properties.
Write “OK” for items checked or actual number checked in field.
Use “N/A” for items that are not applicable to the property that is
being certified.
A. Drainage facilities certification
1. Pond Certification
-volume verification
a.topographic records and volume
b.cross-sections and spot elevations
-positive fall to pan
-side slopes
-invert elevation
-spillway elevation
-placement and size of riprap
--- grading
-orifice plate installation and size_
-compaction of berm
-structural integrity of pond
2. Swales
-location (are they within easement)
-dimensions and cross-section verification
-longitudinal slopes and side slopes
-spot elevations
-permanent erosion control measures (drop structures, riprap,
etc....)
-tie-in to pipes, pans, curbs, etc....
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
_
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
The water quality pond has not been
completed with this initial phase of the
project. We are proposing to delay the
construction of this facility until after all the
construction is completed to make sure we
aren't introducing construction sediment to
the bioretention pond. The owner is going
to pay an escrow amount so the City can
be assured it will be constructed in the
future.
-weir size (elevations, size, opening, etc.)
-available freeboard
-landscaping infringement on swales
3. Pipes
-size and type
-slopes (as-built and comparison to minimum 0.4% slope)
-pipe capacity calculations if slopes are significantly
altered
-invert elevations
-installation and backfill material
-cover
-encasement and clearance from other utility lines close by
-joints
4. Concrete Pan Channels
-size
-slope
-super elevation
-cross - section
-thickness
-elevations
5. Inlets
-size and type
-size of opening (or name of standard used)
-grate elevation
-invert elevation
-box size
Okay per Sailer Construction
Okay per Sailer
Okay per Sailer Construction
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
6. Cross pans
-size
-type
-grade
-elevation
-cross-sectional depth
-tie-in to curb and gutter
7. Culverts
-size
-type
-invert elevation
-headwalls
8. Underdrains
-size
-type
-cover
-backfill
-geotextiles
-cleanouts
9. Curb cuts
-size
-tie in to swale, pipe, etc...
The contractor was made aware of one missing curb cut on the southeast corner of the south
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
parking lot. They will be adding it this week.
B. Certification of Grade Elevations Adjacent to Drainage
Facilities:
-minimum opening elevations
-top of foundation elevations
-comparison to 100 year WSEL’s (Freeboard requirements and
floodplain issues)
C. Certification of Erosion Control Measures:
1. Permanent Measures:
-Permanent vegetation (6” bare spots and weeds under control)
-riprap
-riprap bedding
-drop sections
-sediment basins/water quality ponds
-netting mats/blankets
-mulching
2. Temporary Measures:
-mulching
-inlet filter installation
-check bale dams
-seeding and temporary vegetation
-silt fence
D. Site Cleanup After Construction
-construction clean up
-smoothing of ruts
-reseeding
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
Construction is still continuing on the
northwest and north side site and some work
was continuing on the building on the
Sierra Trading Post building on the south
side. There is still some cleanup that
will need to be done before opening. The
contractor is aware of it and will finish
as soon as construction is complete.
E. Statement of Compliance
This certification is signed and stamped and by signing this
form the engineer(s) attests that they have inspected the site and
to the best of their knowledge the as-built conditions of the
drainage facilities are as described in the above form and in the
redlined plans enclosed.
Failure to properly disclose all known information could result
in the rejection of this certification and prevent the release of
any Stormwater Utility holds on Building Permits and/or Certificates
of Occupancy.
F. Signature and Stamp by a Colorado Registered Professional
Engineer.
Samuel M. Eliason
Colorado Licensed Professional Engineer
CO P.E. # 38212
EX
H
I
B
I
T
A AR
E
A
OF
SI
T
E
DR
A
I
N
A
G
E
CE
R
T
I
F
I
C
A
T
I
O
N
Project Number:U13011 Location:Fort Collins, CO
Date:September 30, 2014
EROSION CONTROL MEASURE Units
Estimated
Quantity
Unit
Price
Total
Price
LF 100 $2.50 $610.00
Remove 3" Asphalt SY 244 $5.00 $705.00
Remove Curb & Gutter LF 141 $4.00 $600.00
CY 150 $10.00 $1,500.00
CY 78 $44.00 $3,432.00
CY 6 $40.00 $240.00
CY 13 $46.50 $604.50
LF 106 $20.00 $2,120.00
EA 1 $6,000.00 $6,000.00
Nyoplast Drain Inlet EA 1 $1,500.00 $1,500.00
6" PVC Underdrain Pipe LF 90 $10.00 $900.00
4" PVC Underdrain Pipe LF 100 $8.00 $800.00
TOTAL = $19,011.50
TOTAL = $28,517.25
REQUIRED AMOUNT OF SECURITY =$28,517.25
The Square - Phase 1
Water Quality Pond Cost Estimate
Bioretention Sand Media
AMOUNT OF SECURITY = 1.5 x $19,011.50
Excavation
Sawcut Asphalt
CDOT Aggregate #4
Concrete Pan
Concrete Outlet Structure
Pea Gravel
=
C:\United Civil\Dropbox\Projects\U13011-Square\Docs\Estimates\U13011_Detention Pond-Escrow-Estimate.xls
EXHIBIT B
APPENDIX 4
Site Drainage Certification – Part 2
February 20, 2015
1501 Academy Ct. Suite 203 |Fort Collins, CO 80524 |970-530-4044 |www.unitedcivil.com
February 20, 2015
Mr. Wes Lamarque
Stormwater Department
City of Fort Collins Utilities
700 Wood Street
Fort Collins, CO 80521
RE: Site Drainage Certification – Part 2
The Square
Fort Collins, CO
United Civil Project #U13011
On February 12th and 20th, 2015, United Civil Design Group, LLC personnel conducted a site visit
at The Square redevelopment project, located in Fort Collins, CO. The purpose of the site visit
was to verify and document the drainage facilities shown on the Utility Plans for The Square
originally prepared on 3/11/2014 and amended on 11/5/2014, 12/11/2014, and 1/22/2015.
This site drainage certification only applies to the north half of the site that is usable to Trader
Joe’s. The south half of the site for Sierra Trading Post was previously certified on October 1,
2015. The area of certification is highlighted on the original drainage plan which is attached as
Exhibit A.
In addition, the site drainage certification does not include the water quality pond on the east
side of the site. It was decided to delay construction on that pond until the end of construction
in order to keep construction sediment out of the bioretention facility. The owner already put
up security for the future construction of the pond when the Site Drainage Certification was
prepared for Sierra Trading Post.
There were a few drainage related items that changed during the construction that should be
noted.
•All of the existing parking lots were overlaid so most of the grades shown in the
parking lot were changed up to 2” to reflect the overlay. This did not affect the sites
ability to drain effectively.
•There were a couple of canopy roof drains and a small drainage inlet that were
added on the west side of Trader Joe’s. These storm flows will tie into the existing
storm sewer on the west side of the building as shown on the revised Sheet C2.02.
•There were a few canopy roof drains and two small drainage inlets that were added
on the north side of Trader Joe’s. These storm flows will tie into the proposed
storm sewer on the north side of the building as shown on the revised Sheet C2.02.
This system will temporarily end with a sump drain and pump that will discharge to
the adjacent parking lot on the north side of the building. In the next 6 months, the
storm sewer will be extended to the bioretention facility on the east side of the
building.
1501 Academy Ct. Suite 203 |FORT COLLINS, CO 80524 |970-530-4044 |www.unitedcivil.com
Please note that United Civil personnel were not on site to witness the actual construction of
the infrastructure while it was being installed. However, the contractor has verified that
construction of the storm sewer and concrete pans throughout the site were in conformance to
the plans.
If you have any questions, please contact me at 970-530-4044, or sam.eliason@unitedcivil.com.
Sincerely,
United Civil Design Group, LLC
Sam Eliason, P.E.
Enclosures:
•Drainage Certification Form (5 pages)
•Exhibit A: Drainage Plan with Site Drainage Certification Area shown
•Exhibit B: Sheet C2.02 – Storm Drainage Revisions
DRAINAGE CERTIFICATION FORM
Please fill out all applicable items in this certification form for
single family, multi-family and commercial properties.
Write “OK” for items checked or actual number checked in field.
Use “N/A” for items that are not applicable to the property that is
being certified.
A. Drainage facilities certification
1. Pond Certification
-volume verification
a.topographic records and volume
b.cross-sections and spot elevations
-positive fall to pan
-side slopes
-invert elevation
-spillway elevation
-placement and size of riprap
--- grading
-orifice plate installation and size_
-compaction of berm
-structural integrity of pond
2. Swales
-location (are they within easement)
-dimensions and cross-section verification
-longitudinal slopes and side slopes
-spot elevations
-permanent erosion control measures (drop structures, riprap,
etc....)
-tie-in to pipes, pans, curbs, etc....
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
_
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
The water quality pond has not been
completed with this initial phase of the
project. We are proposing to delay the
construction of this facility until after all the
construction is completed to make sure we
aren't introducing construction sediment to
the bioretention pond. The owner is going
to pay an escrow amount so the City can
be assured it will be constructed in the
future.
-weir size (elevations, size, opening, etc.)
-available freeboard
-landscaping infringement on swales
3. Pipes
-size and type
-slopes (as-built and comparison to minimum 0.4% slope)
-pipe capacity calculations if slopes are significantly
altered
-invert elevations
-installation and backfill material
-cover
-encasement and clearance from other utility lines close by
-joints
4. Concrete Pan Channels
-size
-slope
-super elevation
-cross - section
-thickness
-elevations
5. Inlets
-size and type
-size of opening (or name of standard used)
-grate elevation
-invert elevation
-box size
Okay per Sailer Construction
Okay per Sailer
Okay per Sailer Construction
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
6. Cross pans
-size
-type
-grade
-elevation
-cross-sectional depth
-tie-in to curb and gutter
7. Culverts
-size
-type
-invert elevation
-headwalls
8. Underdrains
-size
-type
-cover
-backfill
-geotextiles
-cleanouts
9. Curb cuts
-size
-tie in to swale, pipe, etc...
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
B. Certification of Grade Elevations Adjacent to Drainage
Facilities:
-minimum opening elevations
-top of foundation elevations
-comparison to 100 year WSEL’s (Freeboard requirements and
floodplain issues)
C. Certification of Erosion Control Measures:
1. Permanent Measures:
-Permanent vegetation (6” bare spots and weeds under control)
-riprap
-riprap bedding
-drop sections
-sediment basins/water quality ponds
-netting mats/blankets
-mulching
2. Temporary Measures:
-mulching
-inlet filter installation
-check bale dams
-seeding and temporary vegetation
-silt fence
D. Site Cleanup After Construction
-construction clean up
-smoothing of ruts
-reseeding
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
___OK ___N/A
E. Statement of Compliance
This certification is signed and stamped and by signing this
form the engineer(s) attests that they have inspected the site and
to the best of their knowledge the as-built conditions of the
drainage facilities are as described in the above form and in the
redlined plans enclosed.
Failure to properly disclose all known information could result
in the rejection of this certification and prevent the release of
any Stormwater Utility holds on Building Permits and/or Certificates
of Occupancy.
F. Signature and Stamp by a Colorado Registered Professional
Engineer.
Samuel M. Eliason
Colorado Licensed Professional Engineer
CO P.E. # 38212
EX
H
I
B
I
T
A
AR
E
A
OF
SI
T
E
DR
A
I
N
A
G
E
CE
R
T
I
F
I
C
A
T
I
O
N
PROPOSED SAWCUT
PROPOSED CURB AND GUTTER
PROPOSED CONCRETE PAN
PROPOSED STORM PIPE
PROPOSED SWALE
PROPOSED NYLOPLAST INLET
PROPOSED DROP INLET
PROPOSED POROUS LANDSCAPE
DETENTION POND
PROPOSED ITEMS
6" F 6" F 6" F 6" F
6"
F
18+50
11
+
0
0
12
+
0
0
13
+
0
0
14+0015+0016+0017+00
18+00
8 X 24 TEE 1
STA 14+38.33
N: 1440155.55
E: 3119047.02
75.48 LF 24" HDPE @ 0.80%
8 X 24 TEE 2
STA 15+13.81
N: 1440155.44
E: 3118971.54
17.44 LF 18" HDPE @ 0.80%
11.25 BEND 1
STA 15+31.25
N: 1440155.41
E: 3118954.10
28.63 LF 18" HDPE @ 0.80%
22.25 BEND 2
STA 15+59.87
N: 1440160.97
E: 3118926.02
23.50 LF 18" HDPE
@ 0.80%
11.25 BEND 3
STA 15+83.37
N: 1440156.34
E: 3118902.98
10.00 LF
18" HDPE
@ 0.80%
INLET 1-2
STA 15+93.37
N: 1440156.32
E: 3118892.98
90.59 LF 18" HDPE @ 0.80%
REDUCER
STA 16+83.96
N: 1440156.19
E: 3118802.39
8 x8 TEE 4
STA 17+62.46
N: 1440156.07
E: 3118723.89
INLET 1-3
STA 18+10.21
N: 1440159.32
E: 3118676.79
8.68 LF 8" HDPE @ 0.80%39.07 LF
8" HDPE
@ 0.80%
SE
E
S
H
E
E
T
C
2
.
0
1
MA
T
C
H
L
I
N
E
63.20 LF 24" HDPE @ 0.80%
EXISTING ROOF DRAIN
(SEE NOTE 6-7)
EXISTING ROOF DRAIN
(SEE NOTE 6-7)
EXISTING WALLS AND
LANDSCAPING TO BE
REMOVED
CURB INLET
N:1440163.99
E:3118719.19
FL 5020.53
INV. OUT 5017.19
%(1'
STA 18+01.53
N: 1440156.01
E: 3118684.82
11.3 LF 8" HDPE @ 2.00%
78.50 LF 8" HDPE
@ 0.80%
3" ROOF DRAIN
FROM CANOPY
3" ROOF DRAIN
FROM CANOPY
189.22 LF 8" PVC @ 1.0%
3" ROOF DRAIN
FROM CANOPY
TIE 8" STORM DRAIN INTO
EXISTING MANHOLE
,19,1
8" INLINE DRAIN WITH
;*5$7(#
INV = 5019.0
4" DRAINS
4" UNDERDRAIN
BEHIND WALL
4" INLINE DRAIN W/
DOMED GRATE
4" INLINE DRAIN W/
DOMED GRATE
4" UNDERDRAIN
BEHIND WALL
4" STORM DRAINS
PROPERTY CORNER
N:1440276.89
E:3119169.42
PROPERTY CORNER
N:1440276.29
E:3118949.74
PROPERTY CORNER
N:1440209.08
E:3118592.94
TEMPORARY SUMP DRAIN
WITH PUMP TO DISCHARGE
TO THE ADJACENT PARKING LOT
5005
5010
5015
5020
5025
5030
5005
5010
5015
5020
5025
5030
14+0014+5015+0015+5016+0016+5017+0017+5018+0018+50
8
X
2
4
T
E
E
1
ST
A
:
1
4
+
3
8
.
3
3
IN
V
.
=
5
0
1
4
.
1
6
8
X
2
4
T
E
E
2
ST
A
:
1
5
+
1
3
.
8
1
IN
V
.
=
5
0
1
4
.
7
6
11
.
2
5
B
E
N
D
1
ST
A
:
1
5
+
3
1
.
2
5
IN
V
.
=
5
0
1
4
.
9
0
22
.
2
5
B
E
N
D
2
ST
A
:
1
5
+
5
9
.
8
7
IN
V
.
=
5
0
1
5
.
1
3
11
.
2
5
B
E
N
D
3
ST
A
:
1
5
+
8
3
.
3
7
IN
V
.
=
5
0
1
5
.
3
2
IN
L
E
T
1
-
2
ST
A
:
1
5
+
9
3
.
3
7
5,
0
IN
V
.
I
N
=
5
0
1
5
.
6
1
'
(
W
)
IN
V
.
O
U
T
=
5
0
1
5
.
4
0
'
(
E
)
RE
D
U
C
E
R
ST
A
:
1
6
+
8
3
.
9
6
IN
V
.
=
5
0
1
6
.
3
4
8
x
8
T
E
E
4
ST
A
:
1
7
+
6
2
.
4
6
IN
V
.
=
5
0
1
6
.
9
7
IN
L
E
T
1
-
3
ST
A
:
1
8
+
1
0
.
2
1
5,
0
IN
V
.
O
U
T
=
5
0
1
7
.
3
5
(
E
)
63.20 LF
24" HDPE
@ 0.80%
75.48 LF 24" HDPE @
0
.
8
0
%
17.44 LF
18" HDPE
@ 0.80%
28.63 LF
18" HDPE
@ 0.80%
23.50 LF
18" HDPE
@ 0.80%
10.00 LF 18" HDPE @ 0.80%
90.59 LF 18" HDPE @
0
.
8
0
%
39.07 LF 8" HDPE @ 0.80%
PROPOSED GRADE
EXISTING GROUND
8.68 LF 8" HDPE @ 0.80%
100-YEAR HGL
ST
A
:
1
6
+
9
8
.
3
8
IN
V
.
=
5
0
1
4
.
8
2
TO
B
E
L
O
W
E
R
E
D
U
N
D
E
R
S
T
O
R
M
6"
F
I
R
E
S
E
R
V
I
C
E
18" MIN.
78.50 LF 8" HDPE @ 0
.
8
0
%
TEMPORARY SUMP DRAIN WITH
PUMP TO DISCHARGE STORMWATER
FLOWS TO THE ADJACENT PARKING LOT
PR
E
P
A
R
E
D
F
O
R
:
DA
T
E
S
U
B
M
I
T
T
E
D
:
Th
e
e
n
g
i
n
e
e
r
p
r
e
p
a
r
i
n
g
t
h
e
s
e
p
l
a
n
s
w
i
l
l
n
o
t
b
e
r
e
s
p
o
n
s
i
b
l
e
f
o
r
,
o
r
li
a
b
l
e
f
o
r
,
u
n
a
u
t
h
o
r
i
z
e
d
c
h
a
n
g
e
s
t
o
o
r
u
s
e
s
o
f
t
h
e
s
e
p
l
a
n
s
.
A
l
l
ch
a
n
g
e
s
t
o
t
h
e
p
l
a
n
s
m
u
s
t
b
e
i
n
w
r
i
t
i
n
g
a
n
d
m
u
s
t
b
e
a
p
p
r
o
v
e
d
b
y
th
e
p
r
e
p
a
r
e
r
o
f
t
h
e
s
e
p
l
a
n
s
.
CAUTION
SQ
U
A
R
E
S
H
O
P
P
I
N
G
C
E
N
T
E
R
L
L
C
3/
1
1
/
2
0
1
4
TH
E
S
Q
U
A
R
E
15
U13011
Civil Engineering & Consulting
1501 Academy Court, Suite 203
Fort Collins, CO 80524
(970) 530-4044
www.unitedcivil.com
LA
P
T
O
P
-
0
4
NO
N
E
C:
\
U
N
I
T
E
D
C
I
V
I
L
\
D
R
O
P
B
O
X
\
P
R
O
J
E
C
T
S
\
U
1
3
0
1
1
-
S
Q
U
A
R
E
\
C
A
D
D
\
C
P
C2
.
0
1
_
S
T
O
R
M
P
&
P
.
D
W
G
1/
2
2
/
2
0
1
5
4:
5
0
:
5
3
P
M
SM
E
ST
O
R
M
S
E
W
E
R
P
L
A
N
&
P
R
O
F
I
L
E
ST
A
1
4
+
0
0
-
S
T
A
1
8
+
5
0
C2.02
3'
30'
LEGEND
0 30'60'
SCALE: 1" = 30'
15'
CHECKED BY:
CHECKED BY:
CHECKED BY:
CHECKED BY:
CHECKED BY:
APPROVED:
NOTES
5B
1
SM
E
1/
2
2
/
2
0
1
5
ST
O
R
M
D
R
A
I
N
F
O
R
R
O
O
F
D
R
A
I
N
S
A
D
D
E
D
1.EXISTING UNDERGROUND AND OVERHEAD PUBLIC AND PRIVATE
UTILITIES AS SHOWN ARE INDICATED ACCORDING TO THE BEST
INFORMATION AVAILABLE TO THE ENGINEER.
2.ALL STORM SEWER CONSTRUCTION SHALL BE PER CITY OF FORT
COLLINS STANDARD CONSTRUCTION SPECIFICATIONS, LATEST EDITION.
3.ALL PIPE LENGTHS ARE FROM CENTER TO CENTER OF ADJACENT
STRUCTURES UNLESS OTHERWISE NOTED.
4.STORM SEWER MAINS AND ROOF LEADERS SHOWN ON THESE
DRAWINGS AS HIGH DENSITY POLYETHYLENE (HDPE) SHALL BE
WATERTIGHT ADS-N12 OR APPROVED EQUAL.
5.MAINTAIN 10' HORIZONTAL AND 18" VERTICAL MINIMUM SEPARATION
BETWEEN ALL SANITARY SEWER & WATER MAINS & SERVICES.
6.ROOF DRAINS TO BE CONNECTED DIRECTLY TO PROPOSED HDPE STORM
SEWER SHALL BE CONNECTED USING MANUFACTURED TEES.
7.CONTRACTOR SHALL FIELD VERIFY LOCATION OF EXISTING ROOF
DRAINS AS SHOWN PRIOR TO CONSTRUCTION.
8.ALL SITE STORM SEWER AS SHOWN ON THESE DRAWINGS IS PRIVATE.
INLET SCHEDULE
INLET ID TYPE
1-3 8" INLINE DRAIN WITH 12"X12" GRATE
(OR APPROVED EQUAL)
1-2 24" NYLOPLAST DRAIN BASIN
(OR APPROVED EQUAL)
CURB INLET 2'x3' CONCRETE CURB INLET
(OR APPROVED EQUAL)
PRELIMIARY STORM SEWER DESIGN
NOT FOR CONSTRUCTION
NOTE:
THE STORM SEWER SHOWN FROM STATION 10+00 TO STATION 16+83.96 IS A
PRELIMINARY DESIGN ONLY AND NOT FOR CONSTRUCTION. THE FINAL
DESIGN AND LAYOUT OF THIS STORM SEWER WILL BE DETAILED WITH A
FUTURE PHASE OF CONSTRUCTION AND IS NOT TO BE CONSTRUCTED WITH
THIS PHASE. NO MAJOR BUILDING ROOF DRAINS WILL BE CONNECTED TO
THIS STORM SYSTEM UNTIL THE NEXT PHASE. STORMWATER FLOWS THAT
ACCUMULATE IN THE PIPE WILL BE PUMPED OUT OF A SUMP AT INLET 1-2 TO
THE ADJACENT DRIVE LANE TO THE NORTH. THIS TEMPORARY DRAINAGE
SITUATION WILL BE IN PLACE NO LONGER THAN AUGUST 1, 2015.