HomeMy WebLinkAboutOTHER-2022-036-Stormwater operations and maintenance plan agreement Stormwater Operations and Maintenance Plan
4" AGREEMENT
This Operation and Maintenance Agreement ( "Agreement" ) is established this day of ,
20 , by Orange County ( "Owner" ) , who is the
owner of the Property ( hereinafter defined ) , on behalf of the Owner, the Association ( if applicable ) , and
all successor Owners of the Property and the Town of Chapel Hill ( "Town " ) .
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Owner represents , warrants, and agrees that Owner is financially responsible for the maintenance,
repair and replacement of all stormwater control structures, appurtenances and vegetation located on
the Property. Owner agrees to perform the maintenance as outlined in the Stormwater Operations and
Maintenance Plan for each Stormwater Control Measure and as may be applicable or required as part of
the regulations set forth in Section 5 . 4 of the Town of Chapel Hill ' s Land Use Management Ordinance . A
Homeowners Association or Property Owners Association shall not be the financially responsible party
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unless more than 50% of the lots or units on the Property have been sold and a resident of the
Association has been named the president .
Owner agrees that the Town has the right to access the Stormwater Control Measure (s ) ( hereinafter
"SCM " ) on the Property, as deemed necessary in the Town ' s sole discretion , by way of the 'SCM
Maintenance & Access Easement' as recorded on the final plat . Owner recognizes and agrees that
Owner is responsible for the maintenance and upkeep of the SCM Maintenance & Access easement .
Owner acknowledges that Town ' s authorized access to the SCM ( s ) does not create any operation or
maintenance responsibility or obligation on the part of the Town .
Owner shall keep a maintenance record for routine maintenance performed related to SCMs on the
Property ( "SCM Inspection and Maintenance Log" ) . The SCM Maintenance Log shall be kept updated by
the Owner and be submitted to the Town each year as part of the required annual inspection report
package . Any deficiencies noted during routine maintenance shall be corrected , repaired or replaced
immediately by Owner . The Owner agrees to notify the Town of any problems with the system or prior
to any changes to the SCM .
The Owner must submit this executed Agreement with the Stormwater Operations and Maintenance
Plan applicable to the SCMs located on the Property and a copy of the approved As - Built Plans to the
Town . Once approved , the Owner shall submit these documents to Orange County Register of Deeds for
recordation , and proof of submittal shall be provided to the Town prior to issuance of the Certificate of
Occupancy . The Owner shall fulfill the requirements of this Agreement effective upon issuance of the
Certificate of Occupancy . In case the ownership of the SCM transfers , the Owner shall , within thirty ( 30 )
days of transfer of ownership, notify the Town of such ownership transfer .
Project Name : Orange County Southern Human Services Center Phase 1 : Seymour Center Expansion
Parcel Identifier Number : 9880008527
Identify the Stormwater Control Measures on site in the table below .
Stormwater Control Measures Quantity ID Number ( as noted on plan )
Bioretention Cell
Dry Pond
Grassed Swale
Hydrodynamic Separator
Level Spreader
Other Type
Permeable Pavement
Sand Filter
StormFilter
Stormwater Wetland
Underground Detention
Wet Pond
Print Name of Owner : Renee Price
Title & Organizations Board of County Commissioners , Chair/ Orange County
Street Address : 300 West Tryon Street
City, State , Zip : Hillsborough , NC 27278
Phone Number ( s ) ; 919 . 245 . 2130
rprice@orangecounfync .gov
Email :
IN WITNESS WHEREOF, the Owner has hereunto set its hand and seal , or if corporate , has caused this
instrument to be signed in its corporate name by its duly authorized officers and its seal to be hereunto
affixed by authority of its Board of Directors , this the day and year first above written .
Signature of Owner :
STATE OF NORTH CAROLINA
COUNTY OF 0YAOCA C [ county in which acknowledgement taken ]
I , CA Dot Y, 1 v11c M a, ti► , a Notary Public of (Am (AVILe,
County, North Carolina , do hereby certify that � Q h . R • �i COL
personally appeared before me this day and acknowledge the due execution of the forgoing instrument .
Witness my hand and official stamp or seal , this 7,. 1S' day of JIAV C , 20 VOL
Seal
NIE1y44P
67 % Signature of Notary Public
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pv ���`�� My Commission Expires .,
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Stormwater Operations and Maintenance
Log Sheet
FBCIIIty Name : Permit Number :
Orange County Southern Human Services Center Phase l : Seymour Center Expansion 201920166 ( FPZCP-SFRS)
Address .
2501 Homestead Road , Chapel Hill, NC 27516
Owner: Orange County E-mail : obarnes@orangecountync.gov Phone : 919 .245 .2628
Qualified Professional : E-mail : Phone .
Begin Date : End Date : Signature :
Date BMP Type Inspected Cause for Inspection Conditions Requiring Correction Comments and
and ID# By: Actions Taken
Date BMP Type Inspected Cause for Inspection Conditions Requiring Correction Comments and
and ID# By: Actions Taken
Instructions : Record all inspections and maintenance activities for all SCMs at the facility on this form . Use additional log sheets and/or attach
extended comments or documentation as necessary. Submit a copy of this completed Stormwater Operations and Maintenance Log Sheet in the
Annual Inspection Report . Start a new log at the time of submission . More instructions about SCM inspection submittal guidelines can be found
at this website . The following notes provide guidance for completing the Stormwater Operations and Maintenance Log Sheet .
■ BMP ID# — If applicable, use ID# from the approved site plan .
■ Inspected by — Note all inspections and maintenance activities on this form, including the required independent annual inspection .
■ Cause for inspection — Note if the inspection is routine, pre- rainy-season, post-storm, annual, or in response to a noted problem or
complaint .
■ Conditions Requiring Correction — Note any condition that requires correction or indicates a need for maintenance .
■ Comments and Actions Taken — Describe any maintenance performed or will need to be performed in the future .
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Jill • Stormwater Operation and Maintenance Plan
BIORETENTION CELL
Regular inspection and maintenance are necessary to preserve long-term functionality of Stormwater
Control Measures "SCMs " per the original design intent . This Plan outlines the Town of Chapel Hill
requirements for regular inspection and maintenance of Bioretention Cell SCMs . The Owner as defined
in the Agreement shall keep a copy of this Stormwater Operations and Maintenance Plan , the SCM
Inspection and Maintenance Log, and a copy of the approved As - Built Plans in a known set location and
made available to the Town of Chapel Hill upon request .
Annual inspections shall be performed by a qualified licensed Professional Engineer or Landscape
Architect . Routine maintenance and inspection shall be performed by a qualified professional with
NCSU Stormwater Inspection and Maintenance Certification or similar certification .
The qualified professional shall maintain a SCM Inspection and Maintenance Log and make available to
the Town of Chapel Hill upon request . All inspections shall be recorded in the log according to the
frequency in the Inspection and Maintenance Table (Table 1 below ) and within 24 hours after storm
events that exceed 1 . 0 inch of rainfall . Any deficit SCM elements noted during inspection shall be
recorded in the log and immediately corrected , repaired , or replaced . All routine and
corrective/emergency maintenance activities shall be recorded in the log . The log template can be
found at the Town of Chapel Hill Stormwater Control Measures website .
An Annual Inspection and Maintenance Report shall be submitted to the Town of Chapel Hill
Stormwater Department . The report shall detail the status of the SCM and maintenance performed as
outlined in the SCM Inspection Report Guidelines . A copy of the annual report shall be submitted to the
Town of Chapel Hill Stormwater Management Division beginning one year after issuance of the
Certificate of Occupancy .
REQUIRED INSPECTION AND MAINTENANCE TASKS FOR BIORETENTION CELL
NOTE: The following inspection and maintenance table is not an exhaustive list of inspection and
maintenance tasks. It is the responsibility of the professional in the facility to perform
comprehensive maintenance for the SCM to be operational.
FREQUENCY
OF MAINTENANCE ACTIVITIES
INSPECTIONS
Watering is needed twicea week until the plants become established ( commonly
Upon & 8 weeks ) and then as needed during first growing season ( AprilamOctober) ,
construction depending on
Removecompletion Remove and replace dead plants .
or • planting .
Mow any bloretention with turf cover to a height of approximately six to eight
inches • remove grass clippings .
Check inlet, collection system and outlet device for clogging . Remove
quarteraccumulated grit, leaves, debris and any other obstructions and dispose offwnsite .
Inspect for ponding and bare or eroding areas and make ad ustments as
Remove trash and /or debris from the bloretention area .
Twice during
, seasonthe growing Pull out weeds and dead , diseased , or invasives plants preferably by hand .
For bioretention areas without turf cover, supplement triple shredded hard wood
mulch in devoid areas to maintain a maximum 3 inch layer.
e Prune trees and shrubs to best professional practice , Thin vegetation so that
sunlight can penetrate the bloretention
Inspect* Inspect the observation/cleanout wells to ensure that the underdrain is
functioning . If clogging has occurred , wash out the underdrain .
* For bloretention areas without turf cover, remove and replace the mulch layer
ith triple shredded hard wood . The ideal time to reapply mulch is On the late
9 Conduct a soil test for pH and heavy metals and determine the infiltration rate .
spring .
replanting2vn3 years
* An extensive - • - • if 50% minimum coverage throughout
* Perform facility " make ,mmover" to maintain intended landscaping regime and
basin is not achieved in the bloretention after the second growing season .
address - problems detected during routine • - •
to 7 years
growing • ns ,, the vegetation shouldcoverage .
Vegetation
If the bioretention cell suffers from dead or diseased plants or overgrown with
As Needed
(Typical
and/or type of disease to determine the cause of the plant failure .
Problems )
o Remediate the problem by selecting new species and /or implementing an
eradication plan for
o Ensure appropriate plant maintenance is occurring .
o A one -time fertilizer application to establish ground cover is permissible if
a soil test indicates it is necessary . No portion of the dry detention system
shall be fertilized after the initial fertilization that is required to establish
the vegetation .
o Consult with the Town of Chapel Hill Stormwater Management Division
before any aquatic herbicide is used and site specific approval is given .
• If vegetation coverage is not achieved , add reinforcement planting to maintain
desired vegetation density and /or split out perennials to increase plant cover .
Desired vegetation coverage is 50% after 2 growing seasons and 75 % after 5
growing seasons
• Remediate bare soils or erosive gullies .
il to remove the gully, plant a ground
o In perimeter areas , regrade the so
cover and water until it is established . If soil test shows that the pH has
dropped , dolomitic lime shall be applied as recommended .
o Within the pretreatment area , provide erosion control devices such as
reinforced turf matting or riprap to avoid future problems with erosion .
Filter Media Failure
• If the bioretention area shows signs of clogging, identify source of sediment and
work to remediate or eliminate it before proceeding with the following
maintenance tasks .
o Flush the underdrains and capture any sediment before it enters any
downstream stream or storm drain system .
o Conduct one or more test pits to determine the depth of soil
contamination .
o Before remediating the filter bed , remove and temporary store any plants .
o Remove the accumulated sediment to the point where sediment is no
longer observed in the soil media plus an additional 2 inches of soil . Either
replace with new media or till 2 to 3 inches of sand into the upper 8 to 12
inches of soil .
o Dispose of any removed soil in an appropriate off-site location .
o Replant and mulch the area of disturbance .
• If soil test shows that the pH has dropped , dolomitic lime shall be applied as
recommended . k
• If the soil test shows that heavy metals have accumulated , the toxic soils shall be
('
removed , disposed of properly, and replaced with new planting media . j
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Structural Integrity
• Replace or repair any cracked , separated or damaged inlet pipes , drop inlets,
overflow structure, outfalls , impoundment walls or other structural elements .
Functionality
• If flow is bypassing the pretreatment area , regrade to route all flow to the
pretreatment area .
• Sediment Accumulation
o Maintain stable ground cover in the drainage area .
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o Sweep or vacuum sediment on pavement in the contributing drainage
area.
o If sedimentation or clogging is occurring in the inlet, design modification
may be needed to ensure adequate drop or slope between inlet and filter
bed .
o If sediment has accumulated in the forebay area or basin reducing its
depth to 75 % of the original design depth , remove the sediment,
restabilize the area , and replace with clean rock . Search for the source of
the sediment in the drainage area and remedy the problem if possible .
• If greater than one feet of localized bed sinking and/or sediment is observed by
the underdrain or overflow, conduct a test pit excavation by hand to examine
subsurface conditions . Look for sediment across layers , discoloration , voids , loss
of material . Cause of bed sinking may be breached material layers , poor
connections , or damaged pipes . Repair the test pit to full functionality without
cross contamination of the individual material layers .
For additional information or if damage has occurred at the outlet which effects the
receiving water, contact the Town at Chapel Hill Stormwater Management at 919-
969 -7246 ( RAIN ) .
Stormwater Operations and Maintenance Plan
SAND FILTER
Regular inspection and maintenance are necessary to preserve long-term functionality of Stormwater
Control Measures "SCMs " per the original design intent . This Plan outlines the Town of Chapel Hill
requirements for regular inspection and maintenance of Sand Filter SCMs . The Owner as defined in the
Agreement shall keep a copy of this Stormwater Operations and Maintenance Plan , the SCM Inspection
and Maintenance Log, and a copy of the approved As - Built Plans in a known set location and made
available to the Town of Chapel Hill upon request .
Annual inspections shall be performed by a qualified licensed Professional Engineer or Landscape
Architect . Routine maintenance and inspection shall be performed by a qualified professional with
NCSU Stormwater Inspection and Maintenance Certification or similar certification .
The qualified professional shall maintain a SCM Inspection and Maintenance Log and make available to
the Town of Chapel Hill upon request . All inspections shall be recorded in the log according to the
frequency in the Inspection and Maintenance Table (Table 1 below ) and within 24 hours after storm
events that exceed 1 . 0 inch of rainfall . Any deficit SCM elements noted during inspection shall be
recorded in the log and immediately corrected , repaired , or replaced . All routine and
corrective/emergency maintenance activities shall be recorded in the log . The log template can be
found at the Town of Chapel Hill Stormwater Control Measures website .
An Annual Inspection and Maintenance Report shall be submitted to the Town of Chapel Hill
Stormwater Department . The report shall detail the status of the SCM and maintenance performed as
outlined in the SCM Inspection Report Guidelines . A copy of the annual report shall be submitted to the
Town of Chapel Hill Stormwater Management Division beginning one year after issuance of the
Certificate of Occupancy .
REQUIRED INSPECTION AND MAINTENANCE TASKS FOR SAND FILTERS
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NOTE: The following inspection and maintenance table is not an exhaustive list of inspection and
maintenance tasks. It is the responsibility of the professional inspecting the facility to perform
comprehensive maintenance for the SCM to be operational.
c
Table 1 : Inspection and Maintenance Provisions for Sand Filters
Upon
completion of
• If a pretreatment grass filter strip has been built, water twice a week until the
construction
grass become established ( commonly ii weeks ) , depending on rainfall .
• Maintain any grass at the perimeter of the sand filter to a height of
approximately six to eight inches .
• Check inlet, outlet, and conveyance system for any obstructions or clogging .
Once every Remove accumulated grit, leaves, and debris and dispose off-site .
quarter . Remove any trash present on the sand filter surface .
• Inspect for prolonged ponding and bare or eroding areas and make adjustments
as necessary .
Twice during .the growing Remove any vegetation growing on the surface of the sand filter preferably by
hand .
season
• Skim the first inch of sand media .
Annually . If a sedimentation chamber is present, pump out oil and grit .
Structural Integrity
• Replace or repair any cracked , separated or damaged inlet pipes , outfalls , or
other structural elements .
• Remediate bare soils or erosive gullies by regrading the soil to remove the gully,
plant ground cover and water until it is established .
• If erosion has occurred within the forebay or pretreatment area , provide
additional erosion protection such as reinforced turf matting or riprap .
Functionality
• Sediment Accumulation
As Needed o Maintain stable ground cover in the drainage area .
(Typical o Sweep or vacuum sediment on pavement in the contributing drainage area .
Problems ) o If sediment has accumulated in the pre -treatment area to a depth greater
than six inches, remove the top few inches of drainage media and dispose of
it in a location where it will not cause impacts to the SCM or a stream .
Search for the source of the sediment in the drainage area and remedy the
problem .
• Filter Media Failure
o If water is ponding on the surface for more than 24 hours after a storm
event, check to see if the underdrain collection system is clogged and flush
if necessary . It water still ponds , remove the top few inches of filter bed
media and replace . If water still ponds , consult an appropriate professional .
All the sand filter media may need to be replaced .
Will
OEM=
For additional information or if damage has occurred at the outlet which effects the
receiving water, contact the Town at Chapel Hill Stormwater Management at 919 -
969 - 7246 ( RAIN ) .
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Stormwater Operations and Maintenance Plan
UNDERGROUND DETENTION
Regular inspection and maintenance are necessary to preserve long-term functionality of Stormwater
Control Measures "SCMs " per the original design intent . This Plan outlines the Town of Chapel Hill
requirements for regular inspection and maintenance of Underground Detention SCMs . The Owner as
defined in the Agreement shall keep a copy of this Stormwater Operations and Maintenance Plan , any
applicable proprietary manufacturer' s 0 & M Plan , the SCM Inspection and Maintenance Log, and a copy
of the approved As - Built Plans in a known set location and made available to the Town of Chapel Hill
upon request .
Annual inspections shall be performed by a qualified licensed Professional Engineer or Landscape
Architect . Routine maintenance and inspection shall be performed by a qualified professional with
NCSU Stormwater Inspection and Maintenance Certification or similar certification .
The qualified professional shall maintain a SCM Inspection and Maintenance Log and make available to
the Town of Chapel Hill upon request . All inspections shall be recorded in the log according to the
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frequency in the Inspection and Maintenance Table (Table 1 below ) and within 24 hours after storm
events that exceed 1 . 0 inch of rainfall . Any deficit SCM elements noted during inspection shall be
recorded in the log and immediately corrected , repaired , or replaced . All routine and
corrective/emergency maintenance activities shall be recorded in the log . The log template can be
found at the Town of Chapel Hill Stormwater Control Measures website .
An Annual Inspection and Maintenance Report shall be submitted to the Town of Chapel Hill
Stormwater Department . The report shall detail the status of the SCM and maintenance performed as
outlined in the SCM Inspection Report Guidelines . A copy of the annual report shall be submitted to the
Town of Chap
el Hill Stormwater Management Division beginning innin g g g one Year after issuance of the
Certificate of Occupancy .
REQUIRED INSPECTION AND MAINTENANCE TASKS FOR UNDERGROUND DETENTION
NOTE: The following inspection and maintenance table is not an exhaustive list of inspection and
maintenance tasks. It is the responsibility of the professional inspecting the facility to perform
comprehensive maintenance for the SCM to be operational.
Table 1 : Inspection and Maintenance Provisions for Underground Detention
• Check detention chambers and pipes for any obstructions , clogging, or damage .
Remove accumulated grit, leaves, and debris and dispose off-site .
Biannually • Remove any trash or debris present within the drainage area and outfall area .
• Inspect the detention system for structural integrity and any accumulation of
liquids or solids within the unit .
• If the detention is in an area that is salted regularly during winter, the system
Yearly should be rinsed during the springtime to prevent salting agents from
accumulating inside the pipes .
Structural Integrity
• Repair any cracks , spalled areas , rusted areas within the detention chambers .
• Replace any crushed or collapsed pipes under the supervision of a professional
engineer .
• Replace the detention structure if it has severely deteriorated .
• Repair eroded outfall channels with additional riprap armoring or other
permanent lining material .
Functionality
• Sediment Accumulation
As Needed o Maintain stable ground cover in the drainage area .
(Typical o Sweep or vacuum sediment on pavement in the contributing drainage area .
Problems ) o Any accumulated sediment in the detention unit must be disposed to a
waste handling facility .
• Other Pollutants
o Identify and eliminate any sources of excessive oil loading .
o If clogging becomes a persistent issue that prevents drawdown , a trashrack
is required on the discharge orifice within the underground detention
structure .
For additional information or if damage has occurred at the outlet which effects the
receiving water, contact the Town at Chapel Hill Stormwater Management at 919 -
969 -7246 ( RAIN ) .
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Stormwater Operation and Maintenance Plan
WET POND
Mill
Regular inspection and maintenance are necessary to preserve long-term functionality of Stormwater
Control Measures "SCMs " per the original design intent . This Plan outlines the Town of Chapel Hill
requirements for regular inspection and maintenance of Wet Pond SCMs . The Owner as defined in . the
Agreement shall keep a copy of this Stormwater Operations and Maintenance Plan , the SCM Inspection
and Maintenance Log, and a copy of the approved As - Built Plans in a known set location and made
available to the Town of Chapel . Hill upon request .
Annual inspections shall be performed by a qualified licensed Professional Engineer or Landscape
Architect . Routine maintenance and inspection shall be performed by a qualified professional with
NCSU Stormwater Inspection and Maintenance Certification or similar certification .
The qualified professional shall maintain a SCM Inspection and Maintenance Log and make available to
the Town of Chapel Hill upon request . All inspections shall be recorded in the log according to the
frequency in the Inspection and Maintenance Table (Table 1 below ) and within 24 hours after storm
events that exceed 1 . 0 inch of rainfall . Any deficit SCM elements noted during inspection shall be
recorded in the log and immediately corrected , repaired , or replaced . All routine and
corrective/emergency maintenance activities shall be recorded in the log . The log template can be
found at the Town of Chapel Hill Stormwater Control Measures website .
An Annual Inspection and Maintenance Report shall be submitted to the Town of Chapel Hill
Stormwater Department . The report shall detail the status of the SCM and maintenance performed as
outlined in the SCM Inspection Report Guidelines . A copy of the annual report shall be submitted to the
Town of Chapel Hill Stormwater Management Division beginning one year after issuance of the
Certificate of Occupancy .
REQUIRED INSPECTION AND MAINTENANCE TASKS FOR WET POND
NOTE: The following inspection and maintenance table is not an exhaustive list of inspection and
maintenance tasks. It is the responsibility of the professional inspecting the facility to perform
comprehensive maintenance for the SCM to be operational.
Oil
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Table 1 : Inspection and Maintenance Provisions for Wet Pond
Jill 1 ! i ; l
Upon • Watering is needed twice a week until the plants on the vegetated shelf and
completion of perimeter of the basin become established ( commonly &8 weeks ) , depending
construction on rainfall .
• Mow grass surface areas to a height of approximately six to eight inches and
remove grass clippings .
• Check inlet system/forebay and outlet device for any obstructions or clogging .
Once a quarter Remove accumulated grit, leaves , and debris and dispose off-site .
• Remove any trash within the pond area .
• Inspect for ponding and bare or eroding areas and make adjustments before the
next rainfall as necessary .
Twice during
the growing • Pull out dead or diseased plants, weeds, or invasives preferably by hand .
season
• Have the embankment inspected by a dam safety expert .
• Remove woody species on or near embankment area and maintenance access .
Annually A dam safety specialist should be consulted to remove any trees .
• Prune trees and shrubs to best professional practice . Thin vegetation so that
sunlight can penetrate the pond surface .
Vegetation
• If the wet pond suffers from dead or diseased plants or overgrown with invasive
species, evaluate the source of the problem : soils , hydrology, species, and/or
type of disease to determine the cause of the plant failure .
o Remediate the problem by selecting new species and/or implementing
an eradication plan for invasives .
o Ensure appropriate plant maintenance is occurring .
o A one -time fertilizer application to establish ground cover is permissible
As needed if a soil test indicates it is necessary . No portion of the wet pond system
(Typical shall be fertilized after the initial fertilization that is required to establish
Problems ) the vegetation .
o Consult with the Town of Chapel Hill Stormwater Management Division
If algal growth covers 50 % of the area , consult a professional to remove
and control the algal growth .
• If cattails , phragmites, or other invasive plants exceed 50 % of the wet pond ,
remove invasives by physical removal or wiping them with a herbicide . Consult
the Town of Chapel Hill before any aquatic herbicide is used . Site specific
approval is required . Extended periods of dewatering may be a possible
treatment approach for reducing invasives .
• Remediate bare soils or erosive gullies .
o In perimeter areas , regrade the soil to remove the gully, plant a ground
cover and water until it is established . If soil test shows that the pH has
dropped , dolomitic lime shall be applied as recommended .
o Within the pretreatment area , provide erosion control devices such as
reinforced turf matting or riprap to avoid future problems with erosion .
Structural integrity
• Replace or repair any cracked , separated or damaged inlet pipes , outfalls,
impoundment walls or other structural elements .
• If dam embankment or emergency spillway needs maintenance, consult with a
professional .
Functionality
• Sediment Accumulation
o Maintain stable ground cover in the drainage area .
o Sweep or vacuum sediment on pavement in the contributing drainage
area .
o If sedimentation or clogging is occurring in the inlet, design modification
may be needed to ensure adequate drop or slope between inlet and
filter bed .
o If sediment has accumulated in the forebay area reducing its depth to
75 % of the original design depth , remove the sediment off site ,
restabilize the area , and replace with clean rock . Search for the source
of the sediment in the drainage area and remedy the problem if possible .
• If there are visible disturbances to the forebay design , make the necessary
repairs to ensure that the forebay is functioning as intended .
• If evidence of a muskrat or beaver activity is observed , contact a professional to
remove muskrat or beaver .
• If the basin must be drained for an emergency or to perform maintenance , the
flushing of sediment through the emergency drain should be minimized to the
maximum extent practical .
For additional information or if damage has occurred at the outlet which effects the
receiving water, contact the Town at Chapel Hill Stormwater Management at 919 -
969111117246 ( RAIN ) .
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