HomeMy WebLinkAboutFile Documents.834 W Hallam St.0010.2018 (10).ARBK
Page | 1
Civil Engineering
Surveying
& Beyond
Stormwater Best
Management Practices
Operations and
Maintenance Plan
834 W. Hallam Street
Project No. 17031.01
October 2021
Page | 1
Contents
A. Introduction 1
B. System Description & Maintenance 1
1. Roof Gutters and Downspouts 2
2. Area Inlets, Trench Drain and Storm Pipes 3
3. WQCV/Detention Drywell System 4
4. Window Well Drains, Foundation Drain Pipe and Foundation Drywells 5
5. Concrete Ditch Channel 6
6. Inspection Logs 7
7. Stormwater Structure Details 7
A. Introduction
The purpose of this Stormwater Best Management Practices Operations and Maintenance
Plan is to outline a series of recommendations and schedule for inspection and maintenance
of the stormwater collection system at 834 W. Hallam Street in Aspen, Colorado. All
responsibilities for inspection and maintenance, including repair or replacement of system
components, shall be held by the Property Owner(s) or other person/business retained by
the Property Owner(s) to provide all the services described herein. An annual record of
inspections and maintenance shall be kept with this manual and made available to the City
upon request.
B. System Description & Maintenance
The 0.138-acre site has been developed with three (3) multifamily residential buildings,
walkways, parking and landscaping. In general, the topography within the property is
relatively flat with a slight slope from south to north at a slope of approximately 1%-3%
towards the rear of the lot. Site vegetation consists of lawn, ornamental plants, and trees in
good condition. The stormwater collection system consists of a variety of structures
including: roof drains and downspouts; area inlets and a trench drain; a WQCV/Detention
Storm Drywell System; a foundation drain pipe network with window well drains and
foundation drywells; and a covered concrete ditch channel. The following describes each of
these structures, maps their approximate locations and outlines general maintenance
requirements:
Page | 2
1. Roof Gutters and Downspouts
Roof gutters and downspouts collect storm runoff and snow melt water from the roofs and
convey it to the stormwater collection system. Roof gutters and downspouts should be
equipped with heat tape through the entire length to prevent freezing during cold weather. The
following indicates where the downspouts are located:
Figure 1: Downspout Locations
Inspection & Maintenance:
Roof gutters and downspouts should also be cleaned at least once during the Fall to remove
leaves and debris. Additional cleanings may become necessary if excessive leaf accumulation
is observed any time after the previous cleaning. Removed leaves and debris should be
disposed of in the weekly trash receptacle. Roof gutters and downspouts should also be
observed to be free of snow and ice in the winter months. If ice is observed, then the heat tape
must be repaired or replaced.
Page | 3
2. Area Inlets, Trench Drain and Storm Pipes
The stormwater management system consists of a number of area inlets around the buildings, a
trench drain in the parking lot and a stormwater pipe network connecting them all to the WCQV
Detention/Drywell System. The following indicates where these structures are located:
Figure 2: Area Inlets, Trench Drain, Storm Drywell and Storm Pipe Locations
Inspection & Maintenance:
The inlet grates should be inspected after each storm event and cleaned of leaves and debris
on an as needed basis to ensure proper drainage through the grate. Accumulated sediment
may also need to be removed from the flowline of the trench drain. Removed leaves, debris
and sediment should be disposed of in the weekly trash receptacle. More frequent inspections
may be required during the Fall when leaf accumulation could be more intense. If at any time
the water does not drain from a cleaned grate, then a licensed contractor should be contacted
immediately for an emergency repair.
Page | 4
3. WQCV/Detention Drywell System
The stormwater pipe network conveys the collected runoff from the downspouts, area inlets and
trench drain to the WQCV/Detention Drywell System located in the parking lot. The
WQCV/Detention Drywell System is comprised of two (2) concrete drywells. The first drywell
contains an interior stilling well to screen oils, trash, sediment and debris. The drywells are
connected at the bottom by a 10ӯ pipe. The perforated walls of the drywells will then infiltrate
the treated runoff from the minor and major storm events into the ground. The following
indicates where the drywells are located:
Figure 3: WCQV/Detention Drywell System Location
Inspection & Maintenance:
The WQCV/Detention Drywell System should be inspected annually in the Spring and after
every storm exceeding 0.5 inches to verify that the drywells are not retaining water. The two (2)
drywell accesses are the large circular iron solid lids located near the trench drain at the
northeast corner of the property. The stilling well of the WQCV Drywell contains a fabric BMP
Bio-Skirt Bio20 hydrocarbon absorption skirt fastened to the inlet flange of the 8ӯ vertical
“candy cane” riser pipe. This skirt must be replaced annually. A rock sock is also wrapped
around the base of the vertical riser pipe. This rock sock must be sprayed clean and reset
around the pipe base. Dispose of sediment, debris/trash, and any other waste material
removed from the drywells at a suitable disposal site and in compliance with local, state, and
federal waste regulations.
Routinely evaluate the drain-down time of the drywells to ensure the maximum time of 24 hours
is not being exceeded. If drain-down times are exceeding the maximum, drain the drywell via
pumping and clean out the percolation area (the percolation barrel may be jetted to remove
sediment accumulated in perforations). A licensed wastewater collection company must
complete this process. Consider drilling additional perforations in the barrel, if necessary. If
slow drainage persists, the system may need to be replaced. Pumped waters should be
disposed of at the City wastewater facility and dredged material should be disposed of at the
landfill.
Page | 5
4. Window Well Drains, Foundation Drain Pipe and Foundation Drywells
Each window well contains either a floor drain or free draining gravels connected to the
perforated foundation drain system. The perforated pipe is also used to collect groundwater
and convey it into the deep foundation drywells located in the center of the site and in the
parking lot. A foundation drywell is a very deep concrete manhole with perforated walls and an
open bottom to help infiltrate collected waters deeper into the ground beneath or away from the
foundation walls. Each foundation drywell has a heavy solid iron lid for access. The following
indicates where window well drains, foundation drain pipes and foundation drywells are located:
Figure 4: Window Well Drains, Foundation Drain Pipe and Foundation Drywell Locations
Inspection & Maintenance:
The window well drains and gravels should be inspected, cleaned and maintained at the same
time and in the same manner as the area inlets and trench drain.
In general, foundation drain pipe network and foundation drywell should be relatively
maintenance free. The foundation drywell can be accessed for pumping and video
inspection/cleaning of the pipe network by the contractor. The pumped waters should be local
groundwater and not contain any surface contaminants. It is recommended that the
maintenance operator coordinate with the City Engineering Department for temporary disposal
into the site WQCV/Detention Drywell System. The foundation drywell should also be inspected
annually in late Spring.
Page | 6
5. Concrete Ditch Channel
An open irrigation ditch flows along the west side of the property and is piped/channeled under
the parking lot through a covered concrete channel. The following indicates the channel
location:
Figure 5: Concrete Ditch Channel
Inspection & Maintenance:
The concrete ditch channel should be inspected and cleaned annually in the Fall after the ditch
has been turned off. Removed debris and sediment should be disposed of in the weekly trash
receptacle. The channel concrete should be inspected for cracks and sealed with a concrete
grout to ensure watertightness.
Page | 7
6. Inspection Logs
834 W. Hallam Street
O&M Record Log
Year:
Item Dates Inspected Repairs made and by whom
1. Roof Gutters and Downspouts
2. Area Inlets, Trench Drain and Storm Pipes
3. WQCV/Detention Drywell System
4. Window Well Drains, Foundation Drain Pipe and
Foundation Drywells
5. Concrete Ditch Channel
Make a copy of this log for each annual report
Page | 8
7. Stormwater Structure Details
Page | 9
Page | 10
Page | 11
Page | 12
Page | 13
Page | 14
BOUNDARIES UNLIMITED INC.
“….have the ability to
communicate to non-engineer
people.” “They are extremely
dependable and I trust them
125% with any project they are
involved in.”
Julie Olson, MSW
Executive Director
Advocate Safehouse Project
Glenwood Springs, CO
“…Boundaries Unlimited Inc. sets itself apart by their
understanding of municipal budgets and associated
constraints...” “Needless to say my expectations are
high of which Boundaries Unlimited Inc. has
exceeded in every way.”
Pamela Woods
Administrator, Town of Silt, CO
“…. has definitely been able
to think out of the box, and
meet the requirements of
the project.” “….provides
high quality and succinct
communications with the
client. The quality
assurance and control of
their work products are
excellent as well.”
Julie Constan, PE
Sr. Engineer,
Mesa County, CO
“….responded to situations in a timely
and professional manor, and were a
pleasure to work with. I would gladly
work with them again.”
Peter Brixius
Town Manager
Rangely, CO
“Your thorough designs as well as your detailed construction observation have been instrumental
in successfully completing our projects over the years. We also appreciate the timeliness and
economy of your services….”
Steve Vanderleest, PE
Assistant City Engineer
Glenwood Springs, CO
“From the initial permitting, plan set quality; clear through the final construction this project went as
good as any. We look forward to working with you in the future.” “….You have always held your
work to a very high standard and I would be happy to let others know.”
Devin Drayton, Construction Manager
CDOT Region 3 – Traffic and Safety
Grand Junction, CO
“In my 32 years in the construction
industry and inspection service,
Boundaries Unlimited, Inc., stands
out as highly competent,
professional….”
Mike Gruber
Personal Reference
Employed with Eagle County
as Public Works Inspector, CO
STORMWATER BEST MANAGEMENT PRACTICES
OPERATIONS AND MAINTENANCE AGREEMENT
City of Aspen, Colorado
THIS AGREEMENT, made and entered into this
Full Name of Owner)
day of _, 20 , by and between (Insert
hereinafter called the
"Landowner", and the City of Aspen, Colorado, hereinafter called the "City".
WITNESSETH
WHEREAS, the Landowner is the owner of certain real property described as (Pitkin County tax Map/Parcel
Identification Number) located at
and as more fully as follows, to wit:
also known as, , hereinafter called the "Property"; and
WHEREAS, the Landowner is proceeding to build on and develop the property; and
WHEREAS, the stormwater management BMP Operations and Maintenance Plan for the property identified herein
has been approved by the City, herein after called the “Plan”, which is attached hereto as Appendix A and made part
hereof, as approved by the City, provides for management of stormwater within the confines of the Property through
the use of stormwater management or Best Management Practices (BMPs) facilities; and
WHEREAS, the City and the Landowner, its successors and assigns, agree that the health, safety, and welfare of
the residents of City of Aspen, Colorado and the maintenance of water quality require that on-site stormwater
management/BMP facilities be constructed and maintained on the Property; and
WHEREAS, the City requires, through implementation of the Plan from the Landowners dated
and attached hereto, that on-site stormwater management/BMPs as shown on the Plan be
adequately constructed, operated, and maintained by the Landowner, its successors and assigns.
NOW, THEREFORE, in consideration of the foregoing premises, the mutual covenants contained herein,
and the following terms and conditions, the parties hereto agree as follows:
1. Construction of BMP facility by Landowner. The on-site stormwater management/BMP facilities shall be
constructed by the Landowner, its successors and assigns, in accordance with the plans and specifications
approved by the City and identified in the Plan.
2. Duty of Operation and Maintenance of Facility. The Landowner, its successors and assigns, including any
homeowners association, shall adequately operate, inspect, and maintain the stormwater management/BMP
facilities as acceptable to the City and in accordance with the specific operation, inspection, and maintenance
requirements noted in the Plan. Adequate operation and maintenance is herein defined as good working condition
so that these facilities are performing their design functions.
3. Duty of Documentation. The Landowner, its successors and assigns, shall document inspections, maintenance,
and repairs performed and provide said documentation to the City or its representatives upon request.
4. Right of Entry on Property. The Landowner, its successors and assigns, hereby grant permission to the City,
its authorized agents and employees, to enter upon the Property at reasonable times and upon presentation of
proper identification, and to inspect the stormwater management/BMP facilities whenever the City deems
necessary. The purpose of inspection is to follow-up on suspected or reported deficiencies, to respond to citizen
complaints, and/or to assure safe and proper functioning of the facilities. The City shall provide the Landowner,
its successors and assigns, copies of the inspection findings and a directive with timeline to commence with the
repairs if necessary.
5. Failure to Maintain. In the event the Landowner, its successors and assigns, fails to construct, operate and
maintain the stormwater management/BMP facilities in good working condition acceptable to the City, the
City, its authorized agents and employees, may enter upon the Property and take whatever action(s) deemed
necessary to correct deficiencies identified in the inspection report and to charge the costs of such construction
or repairs to the Landowner. It is expressly understood and agreed that the City is under no obligation to install,
construct, or routinely maintain or repair said stormwater management/BMP facilities, and in no event shall this
Agreement be construed to impose any such obligation on the City.
6. Reimbursement by Landowner. In the event the City pursuant to this Agreement, performs work of any nature,
or expends any funds in performance of said work for labor, use of equipment, supplies, materials, and the like,
the Landowner, its successors or assigns, shall reimburse the City upon demand, within thirty (30) days of
receipt thereof for all actual costs incurred by the City hereunder.
7. Duty to Inspect by City. The City, its employees or representatives, shall inspect the stormwater
management/BMP facilities at a minimum of once every three years to ensure their continued and adequate
functioning.
8. Release of City. The Landowner, its executors, administrators, assigns, and other successors in interests, shall
release the City, its employees and designated representatives from all damages, accidents, casualties,
occurrences, or claims which might arise or be asserted against said City, employees, and representatives from
the construction, presence, existence, operative or maintenance of the stormwater management/BMP facilities
by the Landowner or City. In the event that a claim is asserted against the City, its elected officials, City
Officers or employees, the City shall promptly notify the Landowner and the Landowner shall defend, at its own
expense, any suit based on the claim. If any judgment or claims against the City’s employees or designated
representatives shall be allowed, the Landowner shall pay all costs and expenses regarding said judgment or
claim.
9. Recording of Agreement running with the Property. This Agreement shall be recorded in the real property
records of Pitkin County, Colorado, and shall constitute a covenant running with the Property or land, and shall
be binding on the Landowner, its administrators, executors, assigns, heirs and any other successors in interests,
in perpetuity.
IN WITNESS WHEREOF the undersigned have hereunto affixed their signatures as of the date first above written.
LANDOWNER:
By:_ Print Name:
State of Colorado ) :ss
County of Pitkin )
The foregoing Agreement was acknowledged before me this day of , 20_ ,
by .
My Commission Expires:
Notary Public
THE CITY OF ASPEN:
By:_ Print Name:
State of Colorado ) :ss
County of Pitkin )
The foregoing Agreement was acknowledged before me this day of , 20_ ,
by .
My Commission Expires:
Notary Public