HomeMy WebLinkAboutCarmel BMP O&M Draft 12-Aug-2021
BMP OPERATION &
MAINTENANCE MANUAL
Thomas Residence
Project Site Address:
241 1st Avenue SE
Carmel, IN 46033
Prepared For:
Jim Thomas
24-Aug-2021
Prepared By: Andy Cash
Page 1 of 13
TABLE OF CONTENTS
1. Project Narrative
2. Background
3. Inspection Requirements
4. Inspection and Maintenance Activities
• Underground Detention
• Storm Structure Sumps
• Storm Sewer System
• Infiltration Trench
5. Owner Acknowledgement
6. Appendices
• BMP Location Map
• Details
o Nyloplast Basin with Hood/Snout Device
o Storm Sewer Trench/Pipe
o Underground Detention System
o Infiltration Trench
• Inspection Checklists
o Nyloplast Basin with Hood/Snout Device
o Storm Sewer Trench/Pipe
o Underground Detention System
o Infiltration Trench
Page 2 of 13
Project Narrative
Jim Thomas previously demolished the house and garage at 241 1st Avenue SE and plans to
construct a new residential structure with an attached garage. The new structure will be located
towards the south end of the property and accessed with a new driveway extending from the
alleyway south of the property. The owner intends to combine two properties north of the alley
and is requesting the City to vacate the alley right‐of‐way. The proposed development is on a
site located within Clay Township, Hamilton County, Indiana. The site is generally located in
Section 30, Township 18 North, and Range 4 East, Hamilton County Indiana.
The proposed drainage system will collect the roof runoff and discharge to an onsite underground
detention system located north of the house. The detention system will discharge through a
piped outlet to the south property line immediately north of the vacated alley. Additionally, the
owner plans to install a perforated pipe and stone trench stormwater containment beneath the
alley. The alley surface drainage will enter the stone trench through a curb inlet located along
the south edge of the alley. Stormwater quality best management practices for this property
include sump structures with snout/hood devices, an underground detention system and a stone
trench containment.
BMP Owner Contact Information
Jim Thomas
241 1st Avenue SE
Carmel, IN 46033
317‐490‐2841
Page 3 of 13
Background
Best Management Practices (BMP) ‐ Best Management Practices, refer to structural or non‐
structural measures designed to improve stormwater quality. Urban stormwater runoff contains
pollutants that in high concentration impair the quality of natural streams, rivers and lakes.
When compared to stormwater run‐off from natural undeveloped areas, concentrated
developed runoff contains a high amount of pollutants including petroleum‐based products,
fertilizers, pesticides and sediments. Poor stormwater quality can be harmful to the
environment. Impervious surfaces and stormwater detention ponds increase stormwater
temperature and further impairs offsite stormwater quality. Stormwater pollution increases
biological oxygen demand and reduces oxygen levels available for aquatic organisms. Increased
runoff volume and increased flow rate tends to erode and degrade sensitive aquatic habitat.
Residential and commercial paved areas introduce pollutants including heavy metals, oils and
grease that eventually drain to streams and rivers.
BMP Owner ‐ Typically the property owner also owns and maintains the stormwater best
management practices. In some arrangements when agreed to by written contract a property
lessee could agree to operation and accept maintenance responsibilities for the property BMPs.
Stormwater Infrastructure ‐ Stormwater infrastructure includes piped or lined drainageways and
natural drainageways designed to safely and efficiently drain stormwater and protect site
improvements. Stormwater results after grassed areas, paved areas and rooftops can no longer
absorb or “soak up” stormwater and surface flow ultimately results. Stormwater flow either
enters the storm drain system or runs directly into streams, rivers or lakes. The BMP owner
typically manages and maintains the stormwater infrastructure.
Stormwater Detention ‐ Detention areas are used to improve the quality of urban runoff from
roads, parking lots, residential neighborhoods, commercial areas, and industrial sites, and to
reduce peak stormwater runoff rates by providing temporary storage during larger storm events.
If the detention system on your property was constructed early in the development process, it
was probably used to trap sediment from construction activities and should be cleaned before
final acceptance of the drainage improvements. In addition, the detention pond on your
property may provide other benefits such as open space opportunities in addition to reducing
peak runoff rates and improving water quality. A functioning detention pond is a requirement
for stormwater management. You, as the owner of this stormwater feature need to understand
the importance of the detention system and your obligation to assure its continued proper
function. The example detention system inspection checklist provided with this manual will
provide the information you need to operate a fully functional detention system on your
property. The owner shall establish a healthy site perimeter consisting of native vegetation
where possible which can help stabilize the site and improve the detention system function.
Page 4 of 13
Sump Structure ‐ Sump structures collect drainage surface flow and tramp sediment in a portion
of the structure lower than the outlet pipe. Sump structures typically include a hood or snout
covering the outlet pipe which helps collect sediment and debris in the structure and prevent
downstream migration of pollutants. Sump structures require regular removal of sediment from
the lower portion of the structure. When sediment collects to a depth level with the outlet pipe
the structure will no longer function to remove sediments and downstream pollutant migration
will result. Depending on the depth and volume of the sump the owner could remove sediment
by manual methods; otherwise, safe maintenance practices require use of a vacuum truck.
Storm Sewer Pipe – Storm sewers require an annual inspection. It’s best to perform inspections
during dryer times of the year. Storm sewer maintenance and repair should also only occur
during periods of minimal rainfall. The BMP owner should inspect storm sewer inlets frequently
and at a minimum once every six months. When obvious unseen problems exist that reduce the
capacity of the storm sewer the BMP owner should televise the system in an effort to identify
the obstruction or failure. Signs of obstruction for failure include excessive sediment, erosion of
natural channels, visibly failed concrete or plastic piping, pipe or structure settlement. The BMP
owner shall create a written report indicating the nature of the failure and the actions taken to
restore the system.
Page 5 of 13
Inspection Requirements
The BMP owner shall regularly complete all inspections and perform maintenance and when
necessary hire qualified contractors to make significant repairs. The BMP owner shall be
financially responsible for any maintenance or repairs required by the City or its representatives
during the City’s inspections. The approved maintenance plan and inspection forms provided
with this manual should be used as guidance for performing maintenance activities. Completed
inspection forms must be maintained by the BMP owner. The BMP owner shall present
inspection and maintenance records upon request by the City. The City must be notified of any
changes in BMP ownership, major repairs or BMP failure in writing within 30 days.
The letter should be addressed to:
City of Carmel Engineering Department
1 Civic Square
Carmel, IN 46032
The City and/or its representatives have the right to enter the property to inspect BMPs. In the
event that the City finds a BMP in need of maintenance or repair, the City will notify the BMP
owner of the necessary maintenance or repairs and give the landowner a timeframe for
completing the maintenance or repairs. If the maintenance or repairs are not completed within
the designated timeframe, the City shall perform the maintenance or repairs and bill the
landowner for the actual costs for the work. There are requirements regarding the submittal of
annual inspection reports to the City of Carmel Engineering Department. The first report is due
one year after construction is completed, with subsequent reports due each year within the same
month of the initial report. If there are any deficiencies found during the inspection, these should
be addressed. If the inspection report is not received within the month it is due, if there are
deficiencies which were not included in the report, or if any deficiencies included in the report
are not addressed in a timely manner, the BMP owner faces enforcement action from the City.
Page 6 of 13
Inspection & Maintenance Activities
Refer to the checklists provided with this manual for operation, maintenance and inspection of a
BMP and stormwater infrastructure. The checklist is for the use of the BMP owner in performing
routine inspections. The City will perform annual inspections of BMPs, using similar checklists
when necessary. The BMP owner must maintain and update the BMP operations and
maintenance plan as conditions change.
At a minimum, the operations and maintenance plan must include, but is not limited to:
1) Visual inspection and removal of debris from inlets, sump structures and outlet
BMP owners must routinely inspect BMPs to verify that all BMP components are functioning as
designed and are not in danger of failing. All BMPs require regular maintenance to function
properly and efficiently remove sediments and pollutants from stormwater. Maintenance efforts
include sediment removal, mowing and repairs to eroded areas. When present dry stormwater
detention areas should include a permanent and healthy stand of grass. The detention area
should be kept free of debris and mowed regularly. The BMP owner should limit the use of
fertilizers and pesticides within the dry detention area. Storm sewer should be kept clear of
sediments and debris. The natural areas near ditch or swale drains should include rip rap or other
permanent structures in good repair to avoid introducing soil and sediment into the storm sewer
system. The BMP owner agrees to the maintenance and inspection program defined with this
manual. The BMP owner shall document inspections on appropriate forms. The site owner and
contractor shall organize a self‐monitoring program during construction. A trained individual
employed or retained by the project site owner shall prepare and maintain a written evaluation
of the project site by the end of the next business day following each measurable rainfall.
Inspections during construction should immediately follow each storm event and at a minimum,
one (1) time a week. Inspections during the post‐construction operation and maintenance period
must include routine inspection of all stormwater infrastructure to verify that proper functioning
of the system. The stormwater system shall be inspected on an annual basis or upon observed
failure.
Page 7 of 13
Owner Acknowledgement Agreement (“Agreement”)
For good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the undersigned owner (“Owner”) hereby submits this Operation and
Maintenance Manual (“Manual”) to the City of Carmel, Indiana (“City”) as a written
acknowledgement of Owner’s warranty and agreement to institute, maintain, and follow the
water quality Best Management Practices (“BMPs”) listed below, and to follow and abide by the
inspection schedule and maintenance activities listed in this Manual. The Owner also hereby
agrees to provide, at Owner’s cost, all additional maintenance, repair, and/or replacement
services reasonably necessary to maintain the function and longevity of the BMPs from and
including the date this Agreement is executed by Owner to and including the date on which a
new Agreement is filed with the City by another party who assumes all of the obligations and
responsibilities of Owner as set forth herein.
BMPs: Underground Detention System
ADS Sump and Envirohood Structures
Perforated SSD Containment Trench
_______________________________ ________________________
Owner Signature Date
_______________________________ ______________________________
Printed Name Company
STATE OF INDIANA )
) SS:
COUNTY OF HAMILTON )
BEFORE ME, the undersigned, a Notary Public in and for said County and State,
personally appeared _________________________________ Owner subscribed and sworn
before this ____ day of __________________, ________.
______________________________ ______________________________
County of Residence Signature
______________________________
Commission Expiration Date
______________________________
Printed Name
849.37
849.3
7
850.3
7846.351st AVENUE SEALLEY
TREE LINE
N89° 25' 50"W 132.30' (M)
N89° 25' 50"W 131.18' (M)S00° 19' 42"W 131.99'N00° 09' 26"W 132.00'N00° 09' 26"W 188.76'14' B.S.L.PROPERTY LINEPROPERTY LINEPROPERTY LINE
PROPERTY LINE 5' B.S.L.5' B.S.L.
5' B.S.L.
844
843
SCALE: 1" = 20'
BMP MAP
DATE: 23-AUG-20211ST AVENUE
Page 9 of 13
Drainage Basin
Page 10 of 13
ADS Sump and Envirohood Structure
Page 11 of 13
Storm Sewer Trench
Page 12 of 13
Perforated Pipe Stone Containment Trench
Page 13 of 13
Underground Detention System