HomeMy WebLinkAboutTHE LANDING AT LEMAY MULTIFAMILY AND MIXED-USE - FDP230020 - SUBMITTAL DOCUMENTS - ROUND 1 - STORMWATER MANAGEMENT PLANSTORMWATER MANAGEMENT PLAN
THE LANDING AT LEMAY
FORT COLLINS, CO
September 26, 2023
AVANT CIVIL GROUP, LLC
FORT COLLINS, CO 80524
(970)286-7995
_____________________________________________________________________________________________________________________________
AVANT CIVIL GROUP, LLC SWMP: THE LANDING AT LEMAY
1337 RIVERSIDE AVE. #2, FORT COLLINS, CO 80524
September 26, 2023
City of Fort Collins
Stormwater Development Review
700 Wood Street
Fort Collins, CO 80521
RE: STORMWATER MANAGEMENT PLAN
THE LANDING AT LEMAY
To Whom It May Concern:
Avant Civil Group (Avant) is pleased to submit this Stormwater Management Plan for The Landing at
Lemay project. This report outlines Best Management Practices (BMPs) to be implemented with the
proposed construction to minimize potential pollutants in stormwater discharges.
We have prepared this report to accompany the Colorado Department of Public Health and Environment
General Permit for Stormwater Discharge Associated with Construction Activities (aka, Stormwater
Discharge Permit or SDP). The General Permit No. for this SDP is (to be filled-in by permittee), and the
Certification No. for this SDP is (to be filled-in by permittee). The Permit Certification is effective beginning
(to be filled-in by permittee), and initial certification expires (to be filled-in by permittee). A copy of the
issuance cover letter can be found in Appendix D of this document (to be filled-in by permittee).
Please note this Stormwater Management plan (including the Site Maps) is not a static document. It is a
dynamic device that should be kept current and logged as construction occurs. As such, this version was
prepared to facilitate initial plan approvals and permits but does not necessarily reflect the final version or
the transitions throughout the construction process. As the site develops and changes, the contractor is
expected and encouraged to change the content, so the SWMP works as effectively and efficiently as
possible. It shall be the responsibility of the SWMP Administrator and/or the permit holder (or applicant
thereof) to ensure the plan is properly maintained and followed.
If you should have any questions or comments as you review this report, please feel free to contact us at
your convenience.
Sincerely,
AVANT CIVIL GROUP, LLC
DANNY WEBER, PE
Principal
TABLE OF CONTENTS`
_____________________________________________________________________________________________________________________________
AVANT CIVIL GROUP, LLC SWMP: THE LANDING AT LEMAY
1337 RIVERSIDE AVE. #2, FORT COLLINS, CO 80524
1.0 CONTENTS
2.0 PROJECT DESCRIPTIONS AND NATURE OF CONSTRUCTION ......................................... 1
2.1 EXISTING SITE DESCRIPTION .................................................................................................................................. 1
2.2 NATURE OF CONSTRUCTION ACTIVITY ............................................................................................................. 1
2.3 SITE DISTURBANCE ..................................................................................................................................................... 2
2.4 EXISTING TOPOGRAPHIC AND SOIL DATA ...................................................................................................... 2
2.5 RECEIVING WATERS ................................................................................................................................................... 2
2.6 EXISTING SITE CONDITIONS AND VEGETATION ............................................................................................ 3
2.7 EXISTING GROUNDWATER ...................................................................................................................................... 3
2.8 EXISTING GROUND CONTAMINATION .............................................................................................................. 3
3.0 PROPOSED CONSTRUCTION ACTIVITIES ........................................................................... 3
3.1 SEQUENCE OF MAJOR ACTIVITIES ....................................................................................................................... 3
4.0 GENERAL REQUIREMENTS .................................................................................................. 4
4.1 OBJECTIVES .................................................................................................................................................................... 4
4.2 SMWP AVAILABILITY .................................................................................................................................................. 4
4.3 DEFINITIONS ................................................................................................................................................................. 4
4.4 ADDITIONAL PERMITTING ....................................................................................................................................... 4
5.0 ENVIRONMENTAL IMPACT ................................................................................................. 5
6.0 POTENTIAL POLLUTION SOURCES ..................................................................................... 5
6.1 DISTURBED AND STORED SOILS........................................................................................................................... 5
6.2 VEHICLE TRACKING OF SEDIMENT ...................................................................................................................... 6
6.3 MANAGEMENT OF CONTAMINATED SOILS .................................................................................................... 6
6.4 LOADING AND UNLOADING OPERATIONS ..................................................................................................... 6
6.5 OUTDOOR STORAGE OF CONSTRUCTION SITE MATERIALS, BUILDING MATERIALS,
CHEMICALS, ETC. ......................................................................................................................................................... 7
6.6 BULK STORAGE OF MATERIALS ............................................................................................................................. 7
6.7 VEHICLE AND EQUIPMENT MAINTENANCE AND FUELING ....................................................................... 7
6.8 SIGNIFICANT DUST OR PARTICULATE GENERATING PROCESSES .......................................................... 7
6.9 ROUTING MAINTENANCE ACTIVITIES INVOLVING FERTILIZER, PESTICIDES, DETERGENTS,
FUELS, SOLVENTS, OILS ............................................................................................................................................ 8
6.10 ON-SITE WASTE MANAGEMENT PRACTICES ................................................................................................... 8
6.11 CONCRETE TRUCK/EQUIPMENT WASHING ..................................................................................................... 9
6.12 DEDICATED ASPHALT AND CONCRETE BATCH PLANTS ............................................................................ 9
6.13 NON-INDUSTRIAL WASTE SOURCES SUCH AS WORKER TRASH AND PORTABLE TOILETS ........ 9
6.14 SAW CUTTING AND GRINDING ......................................................................................................................... 10
6.15 MATERIAL HANDLING AND SPILL PREVENTION ......................................................................................... 10
6.16 NON-STORMWATER DISCHARGES, INCLUDING CONSTRUCTION DEWATERING NOT
COVERED UNDER THE CONSTRUCTION DEWATERING DISCHARGES GENERAL PERMIT AND
WASH WATER THAT MAY CONTRIBUTE TO POLLUTANTS TO THE MS4 .......................................... 11
7.0 STORMWATER MANAGEMENT CONTROLS .................................................................... 11
7.1 SWMP ADMINISTRATOR ....................................................................................................................................... 11
7.2 OWNER INFORMATION ......................................................................................................................................... 12
7.3 BEST MANAGEMENT PRACTICES (BMPS) FOR STORMWATER POLLUTION PREVENTION ........ 12
TABLE OF CONTENTS`
_____________________________________________________________________________________________________________________________
AVANT CIVIL GROUP, LLC SWMP: THE LANDING AT LEMAY
1337 RIVERSIDE AVE. #2, FORT COLLINS, CO 80524
7.4 STRUCTURAL PRACTICES FOR EROSION AND SEDIMENT CONTROL ................................................ 12
7.5 NON-STRUCTURAL PRACTICES FOR EROSION AND SEDIMENT CONTROL .................................... 15
7.6 PHASED BMP INSTALLATION .............................................................................................................................. 17
7.7 BMP INSPECTION ..................................................................................................................................................... 18
7.8 BMP MAINTENANCE ............................................................................................................................................... 18
7.9 RECORD KEEPING ..................................................................................................................................................... 19
8.0 FINAL STABILIZATION AND LONG-TERM STORMWATER MANAGEMENT ................. 20
8.1 FINAL STABILIZATION ............................................................................................................................................ 20
8.2 LONG-TERM STORMWATER MANAGEMENT ............................................................................................... 21
9.0 ADDITIONAL SWMP AND BMP RESOURCES ................................................................... 22
10.0 REFERENCES ........................................................................................................................ 22
APPENDIX C – LANDSCAPE PLAN
APPENDIX D – COPIES OF PERMITS/APPLICATIONS
APPENDIX E – INSPECTION LOGS
APPENDIX F – CONTRACTOR INSERTS (AS NEEDED)
APPENDIX G – CONTRACTOR INSERTS (AS NEEDED)
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2.0 PROJECT DESCRIPTIONS AND NATURE OF CONSTRUCTION
2.1 EXISTING SITE DESCRIPTION
A tract of land located in the northwest quarter of Section 7, Township 7 North, Range 68 West of
the 6th P.M., City of Fort Collins, County of Larimer, State of Colorado . More specifically it is 28.187-
acres, roughly 19.3 of which is being developed, southeast of the Lemay Ave overpass of Vine Dr.
2.2 NATURE OF CONSTRUCTION ACTIVITY
The project includes construction of a portion of a 2-lane arterial road that will run along the
eastern property line. There are two access points into the development, one being north bound
off existing Duff Drive, and the second being east bound at the constructed intersection of Link
Lane and Cordova Road. The development will include 9 large multifamily buildings and 8 Carraige
Houses, along with a maintenance shed, a private fitness facility, and a clubhouse.
Figure 1 – Vicinity Map
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2.3 SITE DISTURBANCE
The site disturbance will occur across roughly 28.2 acres. It is recommended that existing site
condition photos be taken prior to the demolition.
CALCULATIONS CHART
TOTAL DISTURBED PROJECT AREA 28.2 ACRES
TOTAL "ONSITE" AREA OF DISTURBANCE 19.6 ACRES
TOTAL "OFFSITE" AREA OF DISTURBANCE .13 ACRES
TOTAL STORAGE/STAGING AREA 0 ACRES
TOTAL HAUL ROADS AREA N/A
CONSTRUCTION VEHICLE TRAFFIC AREA N/A
EST. PERCENT OF PROJECT AREA EXPOSED 69.5%
EST. PERCENT VEGETATIVE COVER ~2.5% DENSITY
EXISTING SOIL TYPE D
CLAY
LOAM
APPROX. GROUNDWATER DEPTH 6-9 FEET
NUMBER OF PHASES W/ PROJECT N/A
TOTAL VOLUME OF IMPORTED (+) / EXPORTED (-) MATERIALS 70,000 CUB. YD.
TOTAL AREA OF STOCKPILING OF FILL OR BORROW AREAS OFF SITE 0 SQ. FEET
STEEPEST SLOPE 4:1 H:V
DISTANCE FROM A RIPARIAN AREA OR SENSITIVE AREA N/A FEET
2.4 EXISTING TOPOGRAPHIC AND SOIL DATA
In order to complete the associated construction plans, a topographical survey of the site was
completed. This survey consisted of field measurements made by Kumar and Associates in July of
2022.
A NRCS Custom Soil Resource Report of the property indicates that the soil on site is composed of
83.7% Caruso clay loam, and 52.4% Nunn clay loam. Caruso clay loam is considered somewhat
poorly drained and is in hydrologic Soil Group D. Nunn Clay loam is considered well drained and is
hydrologic Soil Group C.
NRCS indicates a wind erodibility rating of 6 (of a scale of 1 to 8, 1 is most susceptible to erosion).
As such this site does not have a high potential for wind erosion. NRCS ind icates an erosion factor,
K, of 0.24 – 0.32 (range of 0.02-0.69, 0.69 being more susceptible to sheet and rill erosion). As
such, this site has a moderate susceptibility to sheet and rill erosion.
The topography generally slopes from the west to the east. The site slopes with a mild to moderate
grade (i.e., 0.5 - 1±%) through the interior to a low point located at the northeast of the site.
2.5 RECEIVING WATERS
The property historically drains via overland flow from west to east until it is intercepted by an
abandoned irrigation ditch running along the western third of the site. The ditch flows south, but is
eroded and creates overland flow towards the southeast corner. The remaining uncaptured flow
Table 1 – Construction Activities
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moves west to east until flowing off site or is intercepted by existing drainage in the surrounding
properties. Flows from these properties eventually discharge into the Cache La Poudre River. These
drainage ways will continue to be used as the major receiving waters upon completion of The
Landing at Lemay.
2.6 EXISTING SITE CONDITIONS AND VEGETATION
The existing site consists of existing farm fields and existing drainage channels including an
abandoned irrigation ditch.
There is not a significant amount of grade change on the site.
The existing site vegetation consists of native grasses and invasive weeds. Majority of the site is
exposed farm soil. The existing site does not contain any area of impervious surface. It is highly
recommended that pre-construction photos be taken to clearly document vegetative conditions
prior any disturbance activities.
2.7 EXISTING GROUNDWATER
Groundwater depth was measured onsite in July of 2022 by Kumar & Associates, Inc. with 27
borings and the digging of 6 exploratory test pits at various locations spread throughout the
property (see attached Geotechnical Report). At the time of the last measurement (July, 2022),
groundwater ranged from 7’ to 7.5’ below existing elevations.
2.8 EXISTING GROUND CONTAMINATION
No existing groundwater contamination has been identified at this time.
3.0 PROPOSED CONSTRUCTION ACTIVITIES
3.1 SEQUENCE OF MAJOR ACTIVITIES
To complete the project, many basic categories of construction activity will take place. The first
part will be the removal of the existing concrete and asphalt pavement within the construction
limits of the existing road. Once the existing pavements marked for demo have been removed the
topsoil and native grasses that are currently on-site will be removed. Following topsoil stripping,
rough grading of the proposed roadways and detention/irrigation ponds along with drainage
swales will commence. Next, utility installation including sanitary sewer, water main and storm
sewer. Vertical construction of the bridge will commence after the rough grading and any
stabilization efforts at the of onsite detention ponds has been completed and inspected. New
curb/gutter, paving, and sidewalks are expected to begin after the storm sewer is in place. The
final stages of site construction will be fine grading of the areas mentioned above, and the
installation of landscaping/seeding throughout the project. The aforementioned sequencing is an
initial best guess and is subject to change at the Contractor’s discretion.
This project is proposed to be built in one pha se.
Earthwork import to the site is expected to be significant. The site is expected to import fill dirt of
similar geotechnical qualities.
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4.0 GENERAL REQUIREMENTS
4.1 OBJECTIVES
The objective of a Stormwater Management Plan (SWMP) is to identify all potential sources of
pollution likely to occur as a result of construction activity associated with the site construction and
to describe the practices that will be used to reduce the pollutants in stormwater discharges from
the site. The SWMP must be completed and implemented at the time the project breaks ground
and revised as necessary as construction proceeds to accurately reflect the conditions and
practices at the site.
This report summarizes the Stormwater Management Plan for the construction activity that will
occur with The Landing At Lemay in Fort Collins, CO. This plan has been prepared according to
regulations of the Colorado Department of Public Health and Environment (CDPHE), Water Quality
Control Division. This report has been provided to meet the requirements of the City of Fort
Collins Municipal Code §26-498 on water quality control.
4.2 SMWP AVAILABILITY
This report is intended to remain on the construction site to allow for maintenance and inspection
updates and for review during inspection.
4.3 DEFINITIONS
BMP – Best Management Practice encompassing a wide range of erosion and sediment control
practices, both structural and non-structural in nature, intended to reduce or eliminate any
possible water quality impacts from stormwater leaving a construction site.
Erosion Control BMPs – Practices that PREVENT the erosion of soil, such as minimizing the amount
of disturbed area through phasing, temporary stabilization, and preserving existing vegetation.
Sediment Control BMPs – Practices to REMOVE sediment from run-off, such as sediment basins,
silt fence, or inlet protection.
Non-structural BMPs – The implementation of methods, practices, and procedures to minimize
water quality impacts, such as the preservation of natural vegetation, preventive m aintenance, and
spill response procedures.
Structural BMPs – Physical devices that prevent or minimize water quality impacts, such as
sediment basins, inlet protection, or silt fence.
4.4 ADDITIONAL PERMITTING
As mentioned above, this Stormwater Management Pl an is associated with the Colorado
Department of Public Health and Environment Stormwater Permit that is issued by the Water
Quality Control Division of the CDPHE. Additional Environmental permitting not described in this
report may be required as a part of this project. An example is the Construction Dewatering
Permit for groundwater. Another example is the Air Pollution Emission Notice (APEN). The CDPHE
website contains links to both of these permits, as well as many other potential permits. The
Contractor is responsible for ensuring the proper permits are acquired.
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5.0 ENVIRONMENTAL IMPACT
There are no known environmental impacts to endangered species or other environmentally
sensitive features that have been identified in this project area.
Stormwater outfalls are unlikely to impact wetlands.
6.0 POTENTIAL POLLUTION SOURCES
As is typical with most construction sites, there are several potential pollution sources that could
affect water quality. It is not possible for this report to identify all materials used or stored on the
construction site. It is the sole responsibility of the contractor to identify and properly handle all
materials that are potential pollution sources. Likely pollution sources are marked “YES,” unlikely
pollution sources are marked “NO.” Detailed descriptions of each source are also provided for
additional reference. Please note that not all items with a detailed description are present in the
project, and there could be additional pollution sources that are not listed that must be addressed
by the Contractor.
• YES - Disturbed and stored soils
• YES - Vehicle tracking of soils and sediment
• NO - Management of contaminated soils
• YES - Loading and unloading operations
• YES - Outdoor storage of construction site materials, building materials, fertilizers, chemicals,
etc.
• NO - Bulk Storage of Materials
• YES - Vehicle and equipment maintenance and fueling
• YES - Significant dust or particulate generating processes
• YES - Routine maintenance activities involving fertilizers, pesticides, detergents, fuels,
solvents, oils, etc.
• YES - On-site waste management practices (waste piles, dumpsters, etc.)
• YES - Concrete truck/equipment washing
• NO - Dedicated asphalt and concrete batch plants
• YES - Non-industrial waste sources, such as worker trash and portable toilets
• YES - Saw Cutting and Grinding
• NO - Material Handling and Spill Prevention
• NO - Non-Stormwater Discharges including construction dewatering not covered under the
Construction Dewatering Discharges general permit and wash water that may contribute to
pollutants to the MS4
6.1 DISTURBED AND STORED SOILS
Approximately 19.6 acre of the site will be disturbed with the Construction Activities. Once soils
have been disturbed they do not retain the same compaction as in their native state, therefore
surface runoff can cause more soil erosion than was historically observed. In the event that these
erosion control practices do not keep sediment on site a structural barrier (silt fence) will be used
and is called out for on the perimeter. If soil manages to migrate from the disturbed areas onto the
hard surfaces it will be swept or scraped (street sweeping) to prevent the migration of sediment. In
case that sediment is washed away too quickly the curb inlets will need protection (rock sock style
inlet protection).
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Soil stockpiles are expected on this site. Stockpiles in the same respect do not retain the same
compaction and are more susceptible to soil erosion. Stockpiles on this site shall be placed in or
near the center of the site and away from any drainage swales to not require perimeter run off
controls (Materials/Site Management Control). The stock pile will be kept loose, not compacted,
and watered as needed to prevent dust issues (site watering). The stockpile will be monitored for
signs of erosion displacement and sediment accumulation and if conditions warrant it, the
stockpile will be structurally covered or if it is going to sit a long while will be reseeded (temporary
seeding).
6.2 VEHICLE TRACKING OF SEDIMENT
Vehicle tracking of sediment may occur throughout the construction process and along all areas
where the pavement meets the disturbed dirt. This occurs most often after any melt off or rain
conditions when mud collects on vehicles tires and is tracked out onto the road consequently
leaving site. This increases the possibility of sediment discharging to the storm system. To prevent
tracking, access to the site will be limited to construction entrances (vehicle tracking pads to be
installed) on the southwest side of the site and northeast side of the site. Vehicle access will be
limited on muddy days (site management control), in this case parking will be kept to the stabilized
staging area. The tracking pad will be monitored visually every day and if track-out becomes a
significant problem a larger or more robust tracking pad may be installed. Otherwise, all track-out
that reaches the street will be scraped and swept (street sweeping). Secondary controls at the
closest affected inlets will have protection (inlet protection) to capture sediment not swept up in a
timely manner.
Additional measures can be taken to minimize and control sediment discharges from the site due
to vehicle tracking. These measures can include fencing around the site to control access points.
The use of gravel parking areas and wash racks can also be implemented to ensure minimal vehicle
tracking from the site.
6.3 MANAGEMENT OF CONTAMINATED SOILS
All data about the site shows that there is no known contamination on the site. If encountered, the
contractor will have the material stored in a covered area (materials management control) as to not
mix with the stormwater until the material can be identified and proper classification and disposal
methods can be determined in accordance with the various waste laws and with good construction
safety and practices.
6.4 LOADING AND UNLOADING OPERATIONS
There is not anticipated to be a significant amount of export leaving the site.
During this project there will be a diverse amount of loading and unloading. The foundation
workers will have to deliver forms to the site and deliver premixed concrete. Landscapers will have
to pile the materials on site to complete the landscape work. Though the loading and loading
vehicles will be contributing to the track out of materials, depending on the material being
delivered to the site they may have a significant spill potential. Where the trailers must access the
site an attempt will be made to keep the vehicle on the VTC or other stabilized storage areas.
When loading and unloading is occurring, depending on the materials, there may be an increased
problem of containers being dropped, punctured, or broken. These off-loading activities will be
located away from storm drains and will have nearby spill kits accessible. Spills on site will be
addressed using spill prevention and response procedures.
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6.5 OUTDOOR STORAGE OF CONSTRUCTION SITE MATERIALS, BUILDING MATERIALS,
CHEMICALS, ETC.
It is anticipated that inert material like wood, tiles, and stone will be stored on site and outside in
the elements. It is also anticipated that materials that do not weather well (cement, mortar, etc.)
will also be located outside. Chemicals are not anticipated to be left outside. As the inert materials
have a lower potential to leave the site they will be monitored during inspection to make sure they
are not being impacted by the exposure to the elements (site management control). The materials
that will need added attention are the cements and mortars as they quickly mix with water and
cause pollution issues. These materials when not stored inside will be placed on pallets to get
above potential surface runoff and covered with tarps or plastic to prevent mixing with stormwater
(materials management control). Very small quantities of chemical are needed to contaminate
stormwater so the fertilizers, paints, form oils, petroleum products, and other typical chemicals, will
be stored in the construction connex box, trailers, vehicles, or the like out of contact with
precipitation (materials management control). If not stored in a location as described, secondary
containment will be required. The contractor shall clearly designate site areas for staging and
storage of building materials.
6.6 BULK STORAGE OF MATERIALS
This site is not expected to store bulk liquid chemicals of more than 55 gallon drums. If this site
does have the need to store liquid chemicals the following procedure should be followed.
These materials should be stored in an area that if a rupture would occur, it would be contained.
The area will need to be located away from the drainage areas and area inlets (site management /
materials management). The containers will be stored in secondary containment area with a fence
so that if a spill were to happen, it would pool in the bottom of the area and be contained.
6.7 VEHICLE AND EQUIPMENT MAINTENANCE AND FUELING
Based on the size of the site and the duration of activities vehicle fueling and vehicle maintenance
is highly likely. As fueling and equipment maintenance usually result in small spills of petroleum
products it is important to monitor these activities carefully. (site management control) Some
grading companies will employee a fuel truck to fill the heavy equipment on site or require the
maintenance of a broken machine. In those cases where the vehicle is not able to be maintained
off site, these activities will be done in the least detrimental way possible. The maintenance and
fueling will be located as far from stormwater features as possible and at least 50 feet from a
stormwater feature (site management/materials management). The fueling activity will have spill
materials nearby and a bucket or other container and shovel located nearby to hang a hose after
filling to catch drips, and to scoop up any dirt that inadvertently mixed with the soil (materials
management). That container will have a lid and be disposed of when the activity is completed.
The maintenance work will be done on a tarp or other material to prevent the residual oils and
greases from mixing with the dirt (materials management). A clearly designated on-site fueling
and maintenance area is suggested
6.8 SIGNIFICANT DUST OR PARTICULATE GENERATING PROCESSES
This project will result in earth moving activities, street sweeping, and track-out and carry out, bulk
materials transport, and saw cutting. As these activities will result in offsite transport of
atmospheric pollution reasonable precautions shall be taken. The project will follow all required
“BMPs” articulated in the Fugitive Dust Manual and a least one additional BMP included during
each of the identified activities in accordance with City Ordinance No. 044 2016. Also a copy of the
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Dust Control Manual will be kept in the trailer during construction for reference. Such activities will
include but not limited to watering the site, covering trucks, slower site speeds and vehicle tracking
mentioned above.
6.9 ROUTING MAINTENANCE ACTIVITIES INVOLVING FERTILIZER, PESTICIDES,
DETERGENTS, FUELS, SOLVENTS, OILS
Fertilizers and Pesticides will be used during the later phases of the project when trying to
establish a healthy vegetation. These chemicals are highly water soluble and are easily and
unnoticeably carried in the stormwater. Proper application rates and recommended timing of
application will be strictly followed and not on days, or the next day, where the weather is calling
for precipitation (materials management control). As most of these types of chemicals will be
brought on by the landscaper they will be required to keep these products in their vehicles until
time of application and not be allowed to leave these materials on the site (site management
control). If these materials are stored on site they shall be kept inside or outside covered and
above the ground to prevent the materials from mixing with water and runoff (materials
management control). Detergents, paints, acids, cement, grout, and solvents will be prevalent in
the interior work of the building (materials management). These materials also are typically easily
mixed with water yet are typically noticeable by discolored, cloudy, or sudsy water. As such, the
contractor will always keep an eye out for these types of differences in water around the site (site
management control). However these materials are to be handled, operated, and cleaned up all
within the inside of the structure, where external use is concerned these materials will be stored in
the construction connex box, trailers, vehicles, or the like out of contact with precipitation
(materials management). If not stored in a location as described secondary containment will be
required (materials management). Fuels and oils might be associated with the smaller equipment
used on site, chainsaws, pumps, generators, etc. As petroleum products are easily suspended in
water and are spread across the top of the water surface. These products when located in water
have rainbow sheen on them. They are also monitored during construction (site management
controls). These products will be stored in the construction connex box, trailers, vehicles, or similar
structure that will minimize contact with precipitation (materials maintenance controls). If not
stored in a location as described secondary containment will be required (materials maintenance).
Any untreated runoff from these activities can be detrimental to wildlife if not cleaned up.
6.10 ON-SITE WASTE MANAGEMENT PRACTICES
All large and heavy weighted waste piles (concrete chunks, excavated pipes, etc.) will be kept in a
neatly grouped pile until the material is to be disposed of properly. These piles will only be stored
the shortest duration possible and will be kept 50 feet from any drainage course or inlet
(Administrative Control). All dry wastes will be maintained through dumpsters and monthly hauler
removal (hauler will be notified if dumpster becomes full and hauled off as needed). Where
available by the hauling company the dumpster will be covered. If not practical or available by the
haul company, an increased removal schedule will be followed an d the “Max fill line” on the
dumpster will be strictly followed. Corners of the dumpsters will be monitored for “Dumpster Juice”
leaking into the soil in dry conditions and rain/melt off conditions looking for it mixing with the
runoff. Dumpsters, like the waste piles, will be located at least 50 feet from any drainage course or
inlet. Workers will be sent around at the end of the day to collect trash to prevent trash being left
out overnight. No construction debris (including broken concrete) will be buried on site.
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6.11 CONCRETE TRUCK/EQUIPMENT WASHING
Concrete will be a portion of this project. It is anticipated that it will be used with the joints around
the manholes, pour in place inlets, curb and gutter installation, sidewalks and bridge construction.
Pre mixed concrete trucks will be used in this process and will be delivered to the site and when
pouring the bridge components. Washing of the concrete equipment will be required to maintain
the concrete equipment. This concrete wash water has a high alkaline content which is hazardous
material to terrestrial and aquatic wildlife. A section of dirt near the entrance will be excavated and
compacted around the sides formed to retain the concrete wash water on site (as an acceptable
practice by the State) so long as the wash water is kept in the washout (concrete washout). There
will be a rock pad for the truck to park on while washing as to prevent tracking from this washout
(VTC). The placement of this washout will be located at least 50 feet from any drainage c ourse or
inlet. Later in the project after the parking lots curb and gutter has been poured the use of a
mobile washout facility will be used on site in a similar location and after the ground has been
leveled (concrete washout – mobile). The contractor (including all masonry and concrete
tradesmen) shall clean out equipment within the washout area so that the runoff is not allowed to
leave the washout. The only exception would be for them to wash in the next day’s pour location.
All concrete workers will be made aware of the where they are to wash (site management controls
& education). If there is a significant amount of spillage when the transfer from concrete truck to
pump truck occurs, a tarp or other ground cloth should be used to collect spillage. (ground cover
control).
6.12 DEDICATED ASPHALT AND CONCRETE BATCH PLANTS
There will be no dedicated asphalt or concrete batch plants erected onsite for this project.
Premixed concrete and paving materials will be delivered to the site and placed.
In the event that a plant is needed, the Contractor should be aware that additional permitting will
be required. In particular, an Air Pollutant Emission Notice (APEN) will need to be obtained from
the CDPHE.
6.13 NON-INDUSTRIAL WASTE SOURCES SUCH AS WORKER TRASH AND PORTABLE
TOILETS
Since facilities are not located nearby for workers to use, trash and sanitary facilities will be
required on the site.
Worker trash will be comingled with the industrial trash and will follow the same controls with the
caveat that a trashcan will be located near the entrance of the site as the contractor will need to
dump their trash from lunch, etc. and this will be emptied weekly or more frequently, if needed.
Designate trash and bulk waste collection areas on-site. Dumpsters should be located near site
entrances to minimize traffic on disturbed soils, and they should be placed on a level soil surface.
When possible, materials should be recycled. Hazardous material waste should be segregated
from other solid waste.
If tipped over and when being cleaned, portable toilet facilities become a potential discharge if not
cleaned up. If human waste is spilled, it will need to be treated as a biological hazard of untreated
sewage and will need to be cleaned up in accordance with Larimer County Health Department
Guidance. The toilets will be staked in a way to prevent tipping on a dirt surface and located at
least 50 feet from a drainage course or inlet. If the site cannot accommodate a portable toilet on
dirt, a containment pan or other secondary containment will be provided. They will also be
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anchored prevent from tipping. All materials shall be properly disposed of in accordance with the
law.
6.14 SAW CUTTING AND GRINDING
The trench work and street connections will require cutting into the City street. This project will
need the use of hardened saws. These saws generate a significant amount of dust. Watering the
cutting surface to prevent airborne particulates (BMP in the City’s Fugitive Dust Manual) is
required. The cutting slurry has a high content of fine particulates (Silica Dust, Metals, etc.) that is
not allowed to discharge as runoff from the site. To prevent slurry from discharging offsite,
contractors will use the minimum amount of water needed to prevent dust and blades from
overheating (site management control). Cutting slurry will be collected via vacuum or allowed to
dry out and be scraped and swept up after the cutting has finished (saw cutting).
The following protocol is recommended to prevent dust and slurry from asphalt and concrete saw
cutting activities from migrating into the existing storm drain system.
• Slurry and cuttings shall be vacuumed during cutting and surfacing operations
• Slurry and cuttings shall not remain on permanent concrete or asphalt pavement overnight
• Slurry and cuttings shall not drain to any natural or constructed drainage conveyance
• Collected slurry and cuttings shall be disposed of in a manner that does not violate
groundwater or surface water standards
6.15 MATERIAL HANDLING AND SPILL PREVENTION
Potential pollution sources, as discussed in earlier sections, are to be identified by the contractor.
Spill prevention procedures are to be determined and put in place before construction by the
contractor. A spill and flooding response procedure must also be determined and put in place
before construction by the contractor. Additionally, steps should be taken to reduce the potential
for leaks and spills to come in contact with stormwater run-off, such as storing and handling toxic
materials in covered areas or storing chemicals within berms or other secondary containment
devices.
A notification procedure must be put in place by the contractor, by which workers would first
notify the site construction superintendent, who would then notify the SWMP Administrator.
Depending on the severity of the spill, the site construction superintendent and SWMP
Administrator would possibly notify the Colorado Department of Public Health and Environment -
Water Quality Control Division, downstream water users, or other appropriate agencies. The
release of any chemical, oil, petroleum product, sewage, etc., which enter waters of the State
of Colorado (which include surface water, groundwater, and dry gullies or storm sewers
leading to surface water) must be reported immediately to the Division’s emergency spill
reporting line at (877) 518-5608. All spills requiring cleanup, even if the spill is minor and does
not need to be reported to the State, should still be reported to the City of Fort Collins Utilities
office at 970-221-6700.
It will be the responsibility of the Contractor to designate a fueling area and take the necessary
precautions to ensure that no stormwater pollution occurs in the event that a fueling area is
needed. Fueling areas shall be located a minimum 100 feet from all drainage courses. A 12 -inch
high compacted earthen ridge capable of retaining potential spills shall enclose fueling areas.
Other secondary containment devices can be used instead of the earthen ridge. The area shall be
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covered with a non-porous lining to prevent soil contamination. Printed instructions for cleanup
procedures shall be posted in the fueling area and appropriate fuel absorbents shall be available
along with containers for used absorbents within the fueling area.
6.16 NON-STORMWATER DISCHARGES, INCLUDING CONSTRUCTION DEWATERING NOT
COVERED UNDER THE CONSTRUCTION DEWATERING DISCHARGES GENERAL
PERMIT AND WASH WATER THAT MAY CONTRIBUTE TO POLLUTANTS TO THE MS4
The Stormwater Construction Permit only covers discharges composed entirely of stormwater. The
discharge of pumped stormwater, ONLY, from excavations, ponds, depressions, etc. to surface
waters, or to a municipal storm sewer system is allowed by the Stormwater Construction Permit, as
long as the dewatering activity and associated BMPs are identified in the Stormwater Management
Plan (SWMP) and are implemented in accordance with the SWMP.
Aside from the exceptions noted above, non-stormwater discharges must be addressed in a
separate permit issued for that discharge. If groundwater is encountered, and dewatering is
required, a Construction Dewatering Permit must be acquired from the Colorado Department of
Public Health and Environment.
Based upon a subsurface exploration report done in 2022 by Kumar & Associates, Inc., ground
water levels indicate that it may be present during construction of sanitary sewer at 6-9’ deep. If
encountered, dewatering activities may be required. Groundwater has in most excavations mixed
with the dirt and as they are pumped, they will add an increased velocity coming out of the out
flow end contributing to erosion and speeding the transport of the suspended sediment particles.
Also, construction dewatering activities must be identified in the Erosion Control Report if they are
to be infiltrated on site. If the material is anticipated to be pumped to a stormwater conveyance
the proper Construction Dewatering Permit must be pulled from the State of Colorado. If pumping
activities are to occur on the site, the use of rock packs on the intake end of the pump will be used
and a silt bag will be used on the outflow end of the pump to reduce the silt and sediment from
leaving the activity (dewatering Control Measure). If this will be under a Dewatering Permit water
samples will be collected in accordance with that permit.
7.0 STORMWATER MANAGEMENT CONTROLS
7.1 SWMP ADMINISTRATOR
A SWMP Administrator must be designated in conjunction with the Stormwater Permit. This person
shall be responsible for developing, implementing, maintaining, and revising the SWMP. The
SWMP Administrator will also be the contact for all SWMP-related issues and will be the person
responsible for the accuracy, completeness, and implementation of the SWMP. The Administrator
should be a person with the authority to adequately manage and direct day-to-day stormwater
quality management activities at the site.
The SWMP Administrator for this site is:
Name: (to be filled in by permittee)
Company: (to be filled in by permittee)
Phone: (to be filled in by permittee)
E-mail: (to be filled in by permittee)
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7.2 OWNER INFORMATION
Name:
Company:
Phone:
E-mail:
7.3 BEST MANAGEMENT PRACTICES (BMPS) FOR STORMWATER POLLUTION
PREVENTION
Beginning from mobilization, and throughout the entire construction of the project, erosion
control devices shall be installed to ensure minimal pollutant migration. These erosion control
devices may be installed in phases, or not at all, depending on actual conditions encountered at
the site. It is the responsibility of the Contractor to make the determination as to what practices
should be employed and when. In the event that a review agency deems BMPs to be insufficient, it
shall be the responsibility of the contractor to implement modifications as directed.
Best Management Practices (BMPs) are loosely defined as a method, activity, maintenance
procedure, or other management practice for reducing the amount of pollution entering a water
body. The term originated from rules and regulations in Section 208 of the Clean Water Act.
Details for Structural and Non-Structural BMPs have been included in Appendix B. These details
should be used for additional information on installation and maintenance of BMPs specified in
this report. It is also intended to serve as a resource for additional BMPs that may be appropriate
for the site that have not specifically been mentioned in the report.
7.4 STRUCTURAL PRACTICES FOR EROSION AND SEDIMENT CONTROL
Structural BMPs are physical devices that are implemented to prevent erosion from happening or
to limit erosion once it occurs. These devices can be temporary or permanent, and installation of
individual components will vary depending on the stage of construction.
A table depicting construction sequence and BMP application/removal has been placed on the
“Dynamic Site Plan” to help document the implementation of these BMPs. Refer to the
Stormwater Management Plan Static Site Plan in the Appendix for the assumed location of all
BMPs. Construction Details for Temporary BMPs are located in the Appendix for reference.
Again, the final determination for which BMP’s will be installed, where they will be located, and
when they will be installed shall be made by the Contractor, along with all documentation
throughout the construction process.
Silt Fencing (Phase I)
Silt fencing shall be provided to prevent migration of sediment off-site or into adjacent properties.
All silt fencing shall be installed prior to any land disturbing activity (demolition, stockpiling,
stripping, grading, etc.). Silt fencing is to be installed prior to site excavation or earthwork
activities.
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Inspections of the silt fence should identify tears or holes in the material and should check for
slumping fence or undercut areas that allow flows to bypass the fencing. Damaged sections of the
silt fence should be removed to maintain BMP effectiveness, typically before it reaches a depth of 6
inches.
It is suggested that silt fencing be located along the North and East bounds of the disturbed areas
of the site, with an exception for the existing road (Link Lane) intersection at the northeast corner
of the disturbed areas. Refer to the Erosion Control Plan (Sheet C 300 through C 304) for additional
clarification.
Sediment Control Log – aka “Straw Wattles” (Phase I)
A Sediment Control Log is a linear roll made of natural materials, such as straw, coconut fiber, or
other fibrous material trenched into the ground and held with a wooden stake. Sediment Control
Logs can be used in many instances. Examples include perimeter control for stockpiles, as part of
inlet protection designs, as check dams in small drainage ways, on disturbed slopes to shorten flow
lengths, or in lieu of silt fencing (where appropriate).
Sediment Control Logs should be inspected for excess sediment accumulation. Sediment should
be removed prior to reaching half the height of the log.
At a minimum, Sediment Control Logs should be used around soil stockpiles (including landscape
material) and at all stormwater discharge locations other than inlets. All proposed landscape
swales, including ones discharging into detention ponds shall have a straw wattle installed
perpendicular to flow every 4” of elevation difference. Refer to the Erosion Control Plan (Sheet C
300 through C 304) for additional clarification.
Vehicle Tracking Control Pads (Phase I)
Vehicle tracking control pads shall be provided to minimize tracking of mud and sediment onto
paved surfaces and neighboring roadways. All vehicle tracking control pads shall be installed prior
to any land disturbing activity (demolition – as necessary, stockpiling, stripping, grading, etc.).
Location of vehicle tracking control pads will be located at any and all existing and future vehicl e
accesses being used during any of the construction phases. These locations will primarily be
dictated by gates or openings in the temporary construction fencing that is expected to be
installed. Vehicle tracking control pads are to be installed prior to demolition (as appropriate), site
excavation or earthwork activities.
Vehicle tracking pads should be inspected for degradation and aggregate material should be
replaced as needed. If the area becomes clogged with water, excess sediment should be removed.
Aggregate material should remain rough, and at no point should aggregate be allowed to
compact in a manner that causes the tracking pad to stop working as intended.
Suggested location for vehicle tracking pad is at the proposed access on the south of the site off
Duff Drive. Refer to the Erosion Control Plan (Sheet C 300 through C 304) for additional
clarification.
Inlet Protection (Phase I & II)
Inlet protection shall be provided for existing inlets to prevent sediment transport from adjacent
earthwork disturbance. Installation of these filters shall occur before adjacent earth disturbing
activities (Phase I implementation). Wattle type filters are to be implemented for new and existing
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inlets where asphalt does not exist. For these inlets, if pavement is constructed adjacent to the
structure or if the area adjacent to the inlet is changed such that the wattle type filter is no longer
effective, it shall be the responsibility of the Contractor to ensure that an appropriate method is
used instead. For example, the wattle filter could be reused, or a gravel-block inlet filter may be
installed. It will be left to the discretion of the Contractor as to whether replacement of any inlet
filter is necessary.
Inlet protection should be inspected regularly for tears that can result in sediment entering an
inlet. Inlet protection should also be inspected for sediment accumulation upstream of the inlet,
and sediment should be removed when the less than half of the capacity is available, or per
manufacturer specifications.
All proposed curb inlets along proposed roadways and upstream flared end sections shall have
inlet protection. Refer to the Erosion Control Plan (Sheet C 300 through C 304) for additional
clarification.
Turf Reinforcement Mat (Phase II)
Turf Reinforcement Mats are utilized at the end of storm drain flared end sections to prevent
scouring and erosion of the soils at the edges of the pipe. Turf Mats will be installed after seeding
of the surrounding areas to allow for grass to take root and ensure easy anchoring of the mats.
Turf Reinforcement Mats should be inspected regularly and replaced if becoming too worn down
to calm flows through the drainage. Turf Reinforcement Mats shall be sized according to the
specifications of the manufacturer as listed in the table on sheet C 304 of the Erosion Control Plan.
Refer to the Erosion Control Plan (Sheet C 300 through C 304) for details regarding specific
placement and specifications for Turf Reinforcement Mats.
Erosion Control Blankets (Phase II)
A temporary degradable rolled erosion control product composed of natural flexible fibers shall be
used on all seeded slopes 4:1 and greater (excluding mulched shrub bed areas). Erosion control
blankets should be utilized to provide erosion control and to facilitate vegetation establishment.
During installation, it is important to ensure that no gaps or voids exist under the material and that
all corners of the material are secured using stakes and trenching. Stakes should be made of
materials that are biodegradable. Continuous contact between the product and the soil is
necessary to avoid failure.
Erosion Control Blankets should be inspected regularly for signs of erosion, including beneath the
mat. If voids are apparent, they should be filled with suitable soil. Inspections should also identify
loose or damaged stakes, as well as loose portions of the blanket. If deficiencies are found, they
should be repaired or replaced.
Concrete Washout Area (Phase II)
A concrete washout should be provided on the site. The washout can be lined or unlined
excavated pits in the ground, commercially manufactured prefabricated containers, or
aboveground holding areas. The concrete washout must be located a minimum of 400 feet from
any natural drainage way or body of water, and at least 1000 feet from any wells or drinking water
sources. Washout areas should not be located in an area where shallow groundwater may be
present. Contractor shall clearly show the desired location and access to the Concrete Washout
Area on the Stormwater Management Plan - Dynamic Site Plan. Contractor shall place a Vehicle
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Tracking Pad if the selected location for the Concrete Washout Area is detached from pavement.
Clear signage identifying the concrete washout should also be provided.
The Concrete Washout Area should be inspected regularly. Particular attention should be paid to
signage to ensure that the area is clearly marked. Confirmation that the washout is being used
should also be noted to ensure that other undesignated areas of the site are not being used
incorrectly as a concrete washout.
It is suggested the Contractor build a concrete wash out pit for this project. It is recommended that
the concrete wash out pit be placed north to the vehicle tracking pad at the southwestern most
entrance to the site. This location is to ensure minimum distance from wash out to exiting the site
while maintaining a minimum of 400’ from any inlets to existing storm drains or constructed
connections to the existing storm drains. The location shown in the Erosion Control Plan (Sheet C
302) is only a suggestion and can be relocated at the discretion of the Contractor.
Permanent/Established Vegetation (Phase IV)
Permanent or established vegetation and landscaping is considered a permanent form of sediment
and erosion control for common open spaces, steep slopes and areas not exposed to prolonged
scour velocities, or acute incipient motion bed shear stresses that will create soil erosion, rill
formation and subsequent sediment transport. Areas where the previous conditions apply will
contain sufficient permanent BMPs, such as riprap or cobble mulch. Permanent vegetation shall
conform to the approved Landscape Plan prepared by Ripley Design Inc. Permanent/Established
vegetation and hardscape defines Phase IV of development.
7.5 NON-STRUCTURAL PRACTICES FOR EROSION AND SEDIMENT CONTROL
Non-Structural BMPs are practices or activities that are implemented to prevent erosion from
happening or to limit erosion once it occurs. These BMPs can be a practice resulting in physical
change to the site, such as mulching or slope stabilization. They can also result in behavioral
changes on the site, such as changes to construction phasing to minimize exposure to weather
elements, or increased employee awareness gained through training.
Protection of Existing Vegetation (Phases I-IV)
Protection of existing vegetation on a construction site can be accomplished through installation
of a construction fence around the area requiring protection. In cases where up -gradient areas are
disturbed, it may also be necessary to install perimeter controls to minimize sediment loading to
sensitive areas such as wetlands.
Trees that are to remain after construction is complete must be protected. Most tree roots grow
within the top 12”-18” of soil, and soil compaction is a significant threat to tree health. As such,
particular care should be taken to avoid activities within the drip-line of the tree. Direct equipment
damage should also be prevented. The most effective way to ensure the health of trees is to
establish a protection zone at the drip-line of the tree to prevent unintended activity in the area
directly surrounding the tree.
Fencing should be inspected and repaired when needed. If damage occurs to a tree, an arborist
should be consulted on how to care for the tree. If a tree is damage beyond repair, the City
Forester should be consulted on remediation measures.
At a minimum, protection to all trees identified for retention on the plans by Ripley Design Inc.
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Stockpile Management (Phases I-III)
Stockpile management should be utilized to minimize erosion and sediment transport from soil
stockpiles. In general, soil stockpiles should be located a minimum of 100 feet from any drainage
way and 50 feet from any storm sewer inlets. Where practical, choose a stockpile location that will
remain undisturbed for the longest period of time as the phases of construction progress.
Sediment control BMPs should be placed around the perimeter of the stockpile, and a designated
access point on the upstream side of the stockpile should be identified. BMPs such as surface
roughening, temporary seeding, mulching, erosion control blankets, or soil binders should be used
to stabilize the stockpile surface.
As a part of stockpile management, regular inspections of the perimeter controls should be
completed. If BMPs have been utilized to stabilize the surface of the stockpile, they should be
inspected and repaired as needed.
While soil stockpiles are not expected with this project, it is possible that foundation excavation or
the delivery landscaping material may generate temporary stockpiles. The location of any such
stockpiles shall be the responsibility of the SWMP Administrator.
Mulching (Phase I-III)
Mulching helps reduce erosion by protecting bare soil from rainfall impact, increasing infiltration,
and reducing runoff. Although often applied in conjunction with temporary or permanent seeding,
it can also be used for temporary stabilization of areas that cannot be reseeded due to seasonal
constraints. The most common type of mulch used is hay or grass that is crimped into the soil to
keep it secure. However, crimping may not be practical on slopes steeper than three to one
(3H:1V).
The Contractor shall mulch all planted areas within twenty-four (24) hours after planting. Only
weed-free and seed-free straw mulch may be used. Straw mulch should be applied at two (2) tons
per acre, and shall be adequately secured by crimping, tackifier, netting or blankets. Hydraulic
mulching may also be used on steep slopes or where access is limited. In the case that hydraulic
mulching is utilized, the Contractor shall use wood cellulose fibers mixed with water at two
thousands to two thousand five hundred (2,000-2,500) pounds per acre and organic tackifier at
one hundred to four hundred (100-400) pounds per acre.
The Contractor is responsible in applying wood chip mulch to all planted trees and shrubs as
shown on the Landscape Plan prepared by Ripley Design Inc.
Wind Erosion/Dust Control (Phase I-IV)
Wind Erosion and Dust Control BMP’s help to keep soil particles from entering the air as a result of
land disturbing construction activities. Attached at the end of the Appendix B is the Fort Collins
Dust Prevention and Control Manual. The purpose of this manual is to establish minimum
requirements consistent with nationally recognize BMP’s for controlling fu gitive dust emissions and
to describe applicable best management practices to prevent, minimize, and mitigate off -property
transport or off-vehicle transport of fugitive dust emissions pursuant to Chapter 12, Article X of the
Fort Collins City Code (§12-150 et. seq) for specific dust generating activities and sources. Examples
include use of a water truck or irrigation/sprinkler system to wet the top layer of disturbed soil,
seeding and mulching, soil binders, or wind fences.
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Please refer to the last three pages of Appendix B for the Dust Control Plan. A Dust Control Plan is
required for all development projects or construction sites with greater than five (5) acres in size.
Street Sweeping (Phases I -IV)
Street sweeping should be used to remove sediment that has been tracked onto adjacent
roadways. Roadways should be inspected at least once a day, and sediment should be removed as
needed. A check of the area inlet protection should be completed after sweeping to ensure
nothing was displaced during sweeping operations. Street sweeping can reduce the sediment
washed into the existing storm drain system. Street sweeping may be necessary on the existing
hardscape areas which receive runoff from the disturbed areas.
Good Housekeeping Practices (All phases)
Good housekeeping practices that will prevent pollution associated with solid, liquid, and
hazardous construction-related materials and wastes should be implemented throughout the
project. Examples of good housekeeping include providing an appropriate location f or waste
management containers, establishing proper building material staging areas, designating paint
and concrete washout areas, establishing proper equipment/vehicle fueling and maintenance
practices. Development of a spill prevention and response plan is another example of Good
Housekeeping practices that should be used on the project. The following items are detailed
examples of some of the good housekeeping practices that should be utilized throughout the
project. It should be noted that a complete list of practices and detailed discussion regarding
good housekeeping has been included within the Potential Pollution Sources section of this report.
Street Sweeping and Vacuuming – Street sweeping and vacuuming should be used to remove
sediment that has been tracked onto adjacent roadways. Roadways should be inspected at least
once a day, and sediment should be removed as needed. A check of inlet protection should be
completed after sweeping to ensure nothing was displaced during sweeping operations.
Waste Management – Designate trash and bulk waste collection areas on-site. When possible,
materials should be recycled. Hazardous material waste should be segregated from other solid
waste. Waste collection areas should be located away from streets, gu tters, watercourses, and
storm drains. Dumpsters should be located near site entrances to minimize traffic on disturbed
soils, and they should be placed on a level soil surface.
Establish Proper Building Material Handling and Staging areas – Clearly designate site areas for
staging and storage of building materials. Provide appropriate BMPs to ensure that spills or leaks
are contained.
Establish Proper Equipment/Vehicle Fueling and Maintenance Practices – If needed, create a clearly
designated on-site fueling and maintenance area that is clean and dry. Provide appropriate BMPs
to ensure that spills or leaks are contained.
7.6 PHASED BMP INSTALLATION
It is important to recognize the four (4) major Development Phases as defined by the State of
Colorado’s Stormwater Discharge Permit (SDP). These four development phases (referred to as
Sequencing by the City of Fort Collins) have been distinguished to aid in the appropriate timing of
installation/ implementation of BMPs at different stages of the construction process. These phases
are described as follows:
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Phase I – Demolition Stage; BMPs for initial installation of perimeter controls
Phase II – Infrastructure Stage; BMPs for utility, paving, and curb installation
Phase III – Vertical Construction Stage; BMPs for individual building construction.
Phase IV – Permanent BMPs and final site stabilization.
The following is a rough estimate of the anticipated construction sequence for site improvements.
The schedule outlined below is subject to change as the project progresses and as determined by
the General Contractor.
Table 2 – Preliminary Permit and Construction Schedule
Included in the back map pockets are two Site Plans: a “Static” Site Plan and a “Dynamic” Site Plan.
The “Static” plan serves to display the overall management plan all at once. However, proper
implementation of BMPs does not occur at once, and certain BMPs may move location in the
construction process; therefore, the “Dynamic” Site Plan is intended for the contractor to write in
the BMP symbols to document the location and time the BMPs are installed and maintained
throughout the entire construction process.
7.7 BMP INSPECTION
All temporary erosion control facilities shall be inspected at a minimum of once every two (2)
weeks and after each significant storm event or snowmelt. Repairs or reconstruction of BMPs, as
necessary, shall occur as soon as possible to ensure the continued performance of their intended
function. It is the responsibility of the SWMP Administrator to conduct bi-weekly inspections,
maintain BMPs if needed, keep records of site conditions and inspections, and update the SWMP
as necessary.
The construction site perimeter, disturbed areas, all applicable/installed erosion and sediment
control measures, and areas used for material storage exposed to precipitation shall be inspected
for evidence of, or the potential for, pollutants entering the drainage system. Erosion and sediment
control measures identified in the SWMP shall be observed to ensure they are operating correctly.
Attention should be paid to areas with a significant potential for stormwater pollution, such as
demolition areas, concrete washout locations, and vehicle entries to the site. The inspection must
be documented to ensure compliance with the permit requirements.
7.8 BMP MAINTENANCE
Any BMPs not operating in accordance with the SWMP must be addressed as soon as possible,
immediately in most cases, to prevent the discharge of pollutants. If modifications are necessary,
TASK BEGINNING
DATE ENDING DATE "BMP-PHASE OF
DEVELOPMENT"
Development Construction Permit
Issued by City of Fort Collins I
Overlot Grading (Demolition) I
Utility Installation II
Road Construction III
Final Stabilization IV
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such modifications shall be documented so that the SWMP accurately reflects on -site conditions.
The SWMP needs to accurately represent field conditions at all times.
Uncontrolled releases of mud, muddy water, or measurable amounts of sediment found offsite will
be recorded with a brief explanation of the measures taken to clean up the sediment that has left
the site, as well as the measures are taken to prevent future releases. This record shall be made
available to the appropriate public agencies (Colorado Department of Public Health and
Environment, Water Quality Control Division; Environmental Protection Agency; City of Fort Collins;
etc.) upon request.
Preventative maintenance of all temporary and permanent erosion control BMPs shall be provided
to ensure the continued performance of their intended function. Temporary erosion control
measures are to be removed after the site has been sufficiently stabilized, as determined by the
City of Fort Collins. Maintenance activities and actions to correct problems shall be noted and
recorded during inspections.
Inspection and maintenance procedures specific to each BMP identified with this SWMP are
discussed in Section 3. Details have also been included in Appendix B.
7.9 RECORD KEEPING
Documentation of site inspections must be maintained. The following items are to be recorded
and kept with the SWMP:
• Date of Inspection
• Name(s) and title(s) of personnel making the inspection
• Location(s) of sediment discharges or other pollutants from the site
• Location(s) of BMPs that need to be maintained
• Location(s) of BMPs that failed to operate as designed or proved inadequate
• Locations(s) where additional BMPs are needed that were not in place at the time of
inspection
• Deviations from the minimum inspection schedule
• Descriptions of corrective action taken to remedy deficiencies that have been identified
• The report shall contain a signed statement indicating the site is in compliance with the
permit to the best of the signer’s knowledge and belief after corrective actions have been
taken.
Provided within Appendix E of this SWMP is an Example Inspection Log to aid in the record
keeping of BMP inspections and maintenance. Photographs, field notebooks, drawings, and maps
should be included by the SWMP Administrator when appropriate.
In addition to the Inspection Log, records should be kept documenting:
• BMP maintenance and operation
• Stormwater contamination
• Contacts with suppliers
• Notes on the need for and performance of preventive maintenance and other repairs
• Implementation of specific items in the SWMP
• Training events (given or attended)
• Events involving materials handling and storage
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• Contacts with regulatory agencies and personnel
• Notes of employee activities, contact, notifications, etc.
Records of spills, leaks, or overflows that result in the discharge of pollutants must be documented
and maintained. A record of other spills responded to, even if they do not result in a discharge of
pollutants, should be made. Information that should be recorded for all occurrences includes the
time and date, weather conditions, reasons for the spill, etc. Some spills may n eed to be reported
to authorities immediately. Specifically, a release of any chemical, oil, petroleum product, sewage,
etc., which may enter waters of the State of Colorado (which include surface water, groundwater ,
and dry gullies or storm sewers leading to surface water) must be reported to the CDPHE.
Additionally, the “Dynamic Site Plan” is intended to be a “living” document where the SWMP
Administrator can handwrite the location of BMPs as they are installed to appropriately reflect the
current site conditions. Also on the “Dynamic Site Plan” is a “Table of Construction Sequence and
BMP Application/Removal” the SWMP Administrator can use to document when BMPs were
installed or removed in conjunction with construction activities. These items have been included as
an aid to the SWMP Administrator, and other methods of record keeping are at his or her
discretion.
This Stormwater Management Plan (both the text and map) is not a static document. It is a
dynamic device intended to be kept current and logged as construction occurs. It shall be
the responsibility of the SWMP Administrator and/or the permit holder (or applicant
thereof) to ensure the plan is properly maintained and followed. Diligent administration is
critical, including processing the Notice to Proceed and noting on the Stormwater
Management Plan the dates that various construction activities occur and respective BMPs
are installed and/or removed.
8.0 FINAL STABILIZATION AND LONG-TERM STORMWATER MANAGEMENT
8.1 FINAL STABILIZATION
Final stabilization of the site will be achieved by either leaving a gravel surface in place of the
existing asphalt roadway or by reseeding. If reseeding is to be used, all disturbed areas will be
seeded, crimped, and mulched within 24 hours of seeding per the FCDCM Chapter 2 Section
6.1.4.9.
Soil amendments such as compost, peat, aged manure, or other similar materials shall also be
utilized. Soil amendments shall be tilled into the soil to a minimum depth of 6” and should comply
with the requirements found in City Code Section 12-132 (also refer to Land Use Code 3.8.21).
A native seed mix shall be installed per the Landscape plan seed mix and installation instructions. If
a seed mix is not specified, a Fort Collins approved seed mix shall be used. The Seed shall be drill
seeded to a depth as specified by the manufacturer.
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Table 3 - Native Grass Seed Mix
Non-seed stabilization is expected to be completed soon after hardscape construction is complete.
Seeded areas will require more time to establish and may need to be irrigated to establish growth.
As defined by the Colorado Department of Public Health and Environment (CDPHE) in the General
Permit Application for Stormwater Discharges, “Final stabilization is reached when all soil
disturbing activities at the site have been completed, and uniform vegetative cover has been
established with a density of at least 70 percent of pre-disturbance levels or equivalent permanent,
physical erosion reduction methods have been employed.” Establishment of 70 percent is required
for a determination for project closure by the City of Fort Collins.
8.2 LONG-TERM STORMWATER MANAGEMENT
The primary method of long-term stormwater management will be bio-retention basins. The bio-
retention basins will remove suspended sediment and pollutants from developed run -off before
entering drainage facilities downstream of the site.
After stabilization, before project closure, all sediment shall be removed from storm piping per
FCDCM Chapter 2 Section 6.1.4.9.
All disturbed areas will receive permanent paving or be vegetated per the Landscape Plan. Low
Impact Development (LID) treatment will provide significant water quality enhancement and will
serve the long-term stormwater management goals for this project.
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9.0 ADDITIONAL SWMP AND BMP RESOURCES
Mile High Flood District
Urban Storm Drainage Criteria Manual - Volume 3 “Best Management Practices”
Colorado Department of Transportation
Erosion Control and Stormwater Quality Guide
BMP Field Academy
EPA Menu of BMPs
Construction Site Storm Water Runoff Control
International Stormwater Best Management (BMP) Database
Rocky Mountain Education Center
Rocky Mountain Education Center
Red Rocks Community College, Lakewood
Keep It Clean Partnership
Boulder
10.0 REFERENCES
1. Drainage Report for The Landing at Lemay, Avant Civil Group, September 27, 2023 (ACG Project
No. 1791-003)
2. City of Fort Collins Landscape Design Guidelines for Stormwater and Detention Facilities,
November 5, 2009, BHA Design, Inc. with City of Fort Collins Utility Services.
3. Fort Collins Stormwater Criteria Manual, City of Fort Collins, Colorado, adopted December 2018,
and referenced in Section 26-500 (c) of the City of Fort Collins Municipal Code
4. Larimer County Urban Area Street Standards, Adopted January 2, 2001, Repealed and Reenacted,
Effective October 1, 2002, Repealed and Reenacted, Effective April 1, 2007, Repealed and
Reenacted, Effective August 1, 2021
5. Soil Resource Report for Larimer County Area, Colorado , Natural Resources Conservation Service,
United States Department of Agriculture.
6. Urban Storm Drainage Criteria Manual, Volumes 1-3, Mile High Flood Control District,
Wright-McLaughlin Engineers, Denver, Colorado, Revised January 2021.
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APPENDIX A
SITE MAPS
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APPENDIX B
EROSION CONTROL DETAILS
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APPENDIX C
LANDSCAPE PLAN
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APPENDIX D
PERMITS / APPLICATIONS
PERMITS
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APPENDIX E
INSPECTION LOGS
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APPENDIX F
CONTRACTOR INSERTS
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APPENDIX G
CONTRACTOR INSERTS