NCS000426_Hickory SCM O&M Plan_20220722

H ICKORY
North Carolina
Life. Well Crafted.
City of Hickory, NC
Municipal SCM OPERATION &
MAINTENANCE PLAN
This Operation and Maintenance (O&M) Plan has been prepared by the City of Hickory
Stormwater Division to address Stormwater Control Measures (SCM) operation and
maintenance requirements for Permit No. NCS000426 to Discharge Stormwater under the
National Pollutant Discharge Elimination System. This plan shall be evaluated annually and
updated as necessary.
This O&M Plan addresses SCMs by describing the activities and procedures the City of Hickory
will implement so that SCMs are properly maintained to ensure on -going functionality and reduce
the potential for discharge of pollutants from the MS4. The O&M Plan for inspection and
maintenance procedures for structural SCMs owned by the City of Hickory, NC.
This O&M Plan is applicable to the following City owned SCMs:
City Owned SCMs
Fire Station 2 Dry Pond
Cloninger Leaf Compost Facility Wet Pond
Fire Station 6 Dry Pond
Public Works Maintenance Facility Rainwater Harvesting
System/Level spreader
Highland Park Dry Pond
All SCMs required by the City's Post -Construction Stormwater Ordinance must have a signed
Operation and Maintenance Agreement on file with the City Stormwater Division.
The Operation and Maintenance Agreement outlines necessary operation and maintenance
procedures that must be followed to ensure the ongoing function of all City owned SCMs.
Attached are O&M procedures for typical SCMs approved for installation by the
City ofHickory.
1 1 P a g e

Bioretention Maintenance Requirements
Important operation and maintenance procedures:
- Immediately after the bioretention cell is established, the plants will be watered twice weekly if needed
until the plants become established (commonly six weeks).
- Snow, mulch or any other material will NEVER be piled on the surface of the bioretention cell.
- Wheeled or tracked equipment will NEVER be driven over the bioretention planting surface.
- Special care will be taken to prevent sediment from entering the bioretention cell.
- If standing water is present 2 days after rainfall, conduct an infiltration test of the soil media.
After the bioretention cell is established, inspect it annually. Inspection activities shall be performed as follows and maintenance
activities shall commence immediately to remediate any problems observed per the table below.
SCM element:
Potential problem:
How to remediate the problem:
The entire SCM
Trash/debris is present.
Remove the trash/debris.
The perimeter of the SCM
Areas of bare soil and/or
Regrade the soil to remove the gully, and plant a ground cover and
erosive gullies have
water until it is established. Provide lime and a one-time
formed.
fertilizer application.
Vegetation is too short or
Maintain vegetation at a height of approximately six inches.
too long.
The inlet device
The pipe is clogged.
Unclog the pipe. Dispose of the sediment off -site.
The pipe is cracked
Replace the pipe.
or otherwise
damaged.
Erosion is occurring in
Regrade the swale to smooth it over and provide erosion control
the swale.
devices such as reinforced turf matting or riprap to avoid
future problems.
Stone verge is clogged or
Remove sediment and replace with clean stone.
covered in sediment.
The pretreatment area
Flow is bypassing
Regrade if necessary to route all flow to the pretreatment
pretreatment area
area. Restabilize the area after grading.
and/or gullies have
formed.
Sediment has accumulated
Search for the source of the sediment and implement best
to a depth greater than three
Inches.
management practices to improve the problem if possible.
Remove the sediment and restabilize the pretreatment area.
Erosion has occurred.
Provide additional erosion protection such as reinforced turf
matting orriprap if needed to prevent future erosion problems.
Weeds are present.
Remove the weeds, preferably by hand. If pesticide is used,
wipe it on the plants. DO NOT SPRAY.
The bioretention
Pruning can affect plant
Prune according to best professional practices. Plant health has
cell:vegetation
health. Best professional
degraded due to the lack of /improper pruning.
practices show that pruning
is needed
to maintain optimal plant
health.
Plants are dead, diseased,
Determine the source of the problem: soils, hydrology, disease,
or dying.
etc. Remedy the problem and replace plants. Provide a one-time
fertilizer application to establish the ground cover if a soil test
indicates it is necessary.
Tree stakes/wires are
Remove tree stake/wires (which can kill the tree if not removed).
present six months after
planting.
21

Bioretention Maintenance Requirements (continued)
SCM element:
Potential problem:
How to remediate the problem:
The bioretention
Mulch is breaking down
Spot mulch if there are only random void areas. Replace whole
cell:soils and mulch
or has floated away.
mulch layer if necessary. Remove the remaining much and
replace with triple shredded hard wood mulch at a maximum
depth of three inches.
Soils and/or mulch
Determine the extent of the clogging - remove and replace either
are clogged with
just the top layers or the entire media as needed. Dispose of the
sediment.
spoil in an appropriate off -site location. Use triple shredded hard
wood mulch at a maximum depth of three inches. Search for the
source of the sediment and remedy the problem if possible.
An annual soil test shows
Dolomitic lime shall be applied as recommended per the soil test
that pH has dropped or
and toxic soils shall be removed, disposed of properly and
heavy metals have
replaced with new planting media.
accumulated in the soil
media.
The underdrain
Clogging has occurred.
Wash out the underdrain system.
system(if applicable)
The drop inlet
Clogging has occurred.
Clean out the drop inlet. Dispose of the sediment off -site.
The drop inlet is damaged.
Repair or replace the drop inlet.
The receiving water
Erosion or other signs of
Contact the local NC DEQ Regional Office.
damage have occurred at
the outlet.
3 1 P a g e

Dry Detention Pond Maintenance Requirements
Important maintenance procedures:
- The drainage area will be managed to reduce the sediment load to the dry extended detention basin.
- Immediately after the dry extended detention basin is established, the vegetation will be watered twice weekly if
needed until the plants become established (commonly six weeks).
- No portion of the dry extended detention pond will be fertilized after the first initial fertilization that is required to
establish the vegetation.
- The vegetation in and around the basin will be maintained at a height of approximately six inches.
- If cracks, seepage, or woody vegetation are present, consult a dam safety expert for a dam inspection.
The measuring device used to determine the sediment elevation shall be such that it will give an accurate depth reading
and not readily penetrate into accumulated sediments.
After the dry detention basin is established, it will be inspected annually. Inspection activities shall be performed as
follows and any problems identified will be remediated immediately per the table below.
SCM element:
Potential problem:
How to remediate the problem:
The entire SCM
Trash/debris is present.
Remove the trash/debris.
The perimeter of the SCM
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, and then plant a
erosive gullies have
ground cover and water until it is established. Provide lime and a
formed.
one-time fertilizer application.
Vegetation is too short or
Maintain vegetation at a height of approximately six inches.
too long.
The inlet device
The pipe is clogged.
Unclog the pipe. Dispose of the sediment off -site.
The pipe is cracked
Replace the pipe.
or otherwise
damaged.
Erosion is occurring in
Regrade the swale if necessary to smooth it over and provide
theswale.
erosion control devices such as reinforced turf matting or riprap to
avoid future problems with erosion.
Stone verge is clogged or
Remove sediment and replace with clean stone.
covered in sediment.
The forebay
Trash/debris is present.
Remove the trash/debris.
Erosion has occurred
Provide additional erosion protection such as reinforced turf
orriprap is displaced.
matting or rip -rap if needed to prevent future erosion problems.
Weeds are present.
Remove the weeds, preferably by hand. If pesticides are used,
wipe them on the plants. DO NOT SPRAY.
4 1 P a g e

Dry Detention Pond Maintenance Requirements (continued)
SCM element:
Potential problem:
How to remediate the problem:
The main treatment area
Sediment has
Search for the source of the sediment and implement best
accumulated and reduced
management practices if possible. Remove the sediment and
the depth to 75% of the
dispose of it in a location where it will not cause impacts to
original design depth (per
streams or the SCM. Revegetate disturbed areas immediately
pond design datasheet).
with sod (preferred) or seed protected with securely staked
erosion mat.
Water is standing more
Check outlet structure for clogging. If it is a design issue,
than 5 days after a storm
consult an appropriate professional.
event.
Weeds and noxious plants
Remove the weeds, preferably by hand. If pesticides are used,
are growing in the main
wipe them on the plants. DO NOT SPRAY.
treatment area.
The embankment
Shrubs or trees have started
Remove shrubs or trees immediately.
to grow on the embankment.
Grass cover is unhealthy or
Restore the health of the grass cover — consult a
eroding.
professional if necessary.
Signs of seepage on the
Consult a professional.
downstream face.
Evidence of muskrat or
Consult a professional to remove muskrats or beavers.
beaver activity is present
An annual inspection by an
Make all needed repairs
appropriate professional
shows that the
embankmentneeds
repair.
The outlet device
Clogging has occurred.
Clean out the outlet device. Dispose of the sediment off -site.
The outlet device is damaged
Repair or replace the outlet device.
The receiving water
Erosion or other signs of
Contact the local NC DEQ Regional Office
damage have occurred at the
outlet.
5 1 P a g e

Level Spreader -Vegetated Filter Strip(LS-VFS) / Restored Riparian Buffer Maintenance
Important maintenance procedures:
- Immediately after the filter strip is established, any newly planted vegetation will be watered twice weekly if
needed until the plants become established (commonly six weeks).
- Once a year, the filter strip will be reseeded to maintain a dense growth of vegetation
- Stable groundcover will be maintained in the drainage area to reduce the sediment load to the vegetation. Two to
three times a year, grass filter strips will be mowed and the clippings harvested to promote the growth of thick
vegetation with optimum pollutant removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and may
be allowed to grow as tall as 12 inches depending on aesthetic requirements (NIPC,1993).
- Forested filter strips do not require this type of maintenance.
- Once a year, the soil will be aerated if necessary.
- Once a year, soil pH will be tested and lime will be added if necessary.
After the filter strip is established, it will be inspected annually. Records of operation and maintenance will be kept in a known
set location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are
found shall be repaired immediately Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
SCM element:
Potential problem:
How to remediate the problem:
The entire SCM
Trash/debris is present.
Remove the trash/debris.
The perimeter of the SCM
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, and then plant a
erosive gullies have
ground cover and water until it is established. Provide lime and a
formed.
one-time fertilizer application.
Vegetation is too short or
Maintain vegetation at a height of approximately six inches.
too long.
The flow splitter device
The flow splitter device
Unclog the conveyance and dispose of any sediment off -site.
(if applicable)
is clogged.
The flow splitter device
Make any necessary repairs or replace if damage is too large
is damaged.
for repair.
The inlet device
The pipe is clogged.
Unclog the pipe. Dispose of the sediment off -site.
The pipe is cracked
Replace the pipe.
or otherwise
damaged.
Erosion is occurring in
Regrade the swale if necessary to smooth it over and provide
the swale.
erosion control devices such as reinforced turf matting or riprap to
avoid future problems with erosion.
Stone verge is clogged or
Remove sediment and replace with clean stone.
covered in sediment.
61

LS-VFS / Restored Riparian Buffer Maintenance Requirements (Continued)
The swale and
The swale is clogged
Remove the sediment and dispose of it off -site.
the level lip
with sediment.
The level lip is cracked,
Repair or replace lip.
settled, undercut, eroded
or otherwise damaged.
There is erosion around the
Regrade the soil to create a berm that is higher than the level lip,
end of the level spreader
and then plant a ground cover and water until it is established.
that shows stormwater has
Provide lime and a one-time fertilizer application.
by-passed it.
Trees or shrubs have begun
Remove them.
to grow on the swale or
just downslope of the
level lip.
The bypass channels
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, and
erosive gullies have
then reestablish proper erosion control.
formed.
Turf reinforcement is
Study the site to see if a larger bypass channel is needed
damaged or riprap is
(enlarge if necessary). After this, reestablish the erosion control
rolling downhill.
material.
The filter strip
Grass is too short or too
Maintain grass at a height of approximately three to six inches.
long.
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, and then plant a
erosive gullies have
ground cover and water until it is established. Provide lime and a
formed.
one-time fertilizer application.
Sediment is building up
Remove the sediment and restabilize the soil with
on the filter strip.
vegetation. Provide lime and a one-time fertilizer
application.
Plants are desiccated.
Provide additional irrigation and fertilizer as needed.
Plants are dead, diseased
Determine the source of the problem: soils, hydrology, disease,
or dying.
etc. Remedy the problem and replace plants. Provide a one-time
fertilizer application.
Nuisance vegetation is
Remove the weeds, preferably by hand. If pesticide is used,
choking out
wipe it on the plants. DO NOT SPRAY.
desirable species.
The receiving water
Erosion or other signs of
Contact the NCDEQ local Regional Office, or the 401 Oversight
damage have occurred at
Unit at 919-733-1786.
the outlet.
71

Grassed Swale Maintenance Requirements
Important maintenance procedures:
- The drainage area of the grassed swale will be carefully managed to reduce the sediment load to the
grassed swale.
- After the first-time fertilization to establish the grass in the swale, fertilizer will not be applied to the
grassed swale.
The grassed swale will be inspected annually. Records of operation and maintenance will be kept in a known set location and
will be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be
repaired immediately.
SCM element:
Potential problem:
How to remediate the problem:
The perimeter of the SCM
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, and then plant a
erosive gullies have
ground cover and water until it is established. Provide lime and a
formed.
one-time fertilizer application
Vegetation is too short or
Maintain vegetation at a height of approximately six inches.
too long.
The entire length of
Trash/debris is present.
Remove the trash/debris.
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, and then re -sod
the swale
erosive gullies have
(or plant with other appropriate species) and water until
formed.
established.
Provide lime and a one-time fertilizer application.
Sediment covers the grass
Remove sediment and dispose in an area that will not impact
at the bottom of the swale.
streams or SCMs. Re -sod if necessary.
Vegetation is too short or
Maintain vegetation at a height of approximately six inches.
too long.
The outlet device
Clogging has occurred.
Clean out the outlet device. Dispose of the sediment off -site.
The outlet device is
Repair or replace the outlet device.
damaged
The receiving water
Erosion or other signs of
Contact the local NC DEQ Regional Office.
damage have occurred at
the outlet.
81

Infiltration System Maintenance Requirements
Important maintenance procedures:
- The drainage area will be carefully managed to reduce the sediment load to the infiltration basin.
- Immediately after the infiltration basin is established, the vegetation will be watered twice
weekly if needed until the plants become established (commonly six weeks).
- No portion of the infiltration basin will be fertilized after the initial fertilization that is required to
establish the vegetation.
- The vegetation in and around the basin will be maintained at a height of approximately six inches.
After the infiltration basin is established, it shall be inspected annually. Records of operation and maintenance shall be kept
in a known set location and shall be available upon request. Inspection activities shall be performed as follows. Any
problems that are found shall be repaired immediately.
SCM element:
Potential problem:
How to remediate the problem:
The entire SCM
Trash/debris is present.
Remove the trash/debris.
The perimeter of the
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, and then plant a
infiltration basin
erosive gullies have
ground cover and water until it is established. Provide lime and a
formed.
one-time fertilizer application.
The inlet device: pipe or
The pipe is clogged
Unclog the pipe. Dispose of the sediment off -site.
swale
The pipe is cracked or
Replace the pipe.
otherwise damaged.
Erosion is occurring in
Regrade the swale if necessary to smooth it over and provide
the swale.
erosion control devices such as reinforced turf matting or riprap to
avoid future problems with erosion.
The forebay
Sediment has
Search for the source of the sediment and remedy the problem if
accumulated and reduced
possible. Remove the sediment and dispose of it in a location
the depth to 75% of the
whereit will not cause impacts to streams or the SCM.
original design depth.
Erosion has occurred
Provide additional erosion protection such as reinforced turf
or riprap is displaced.
matting or riprap if needed to prevent future erosion problems.
Weeds are present.
Remove the weeds, preferably by hand. If pesticide is used,
wipe it on the plants. DO NOT SPRAY.
The main treatment area
A visible layer of
Search for the source of the sediment and remedy the problem if
sediment has
possible. Remove the sediment and dispose of it in a location
accumulated.
where it will not cause impacts to streams or the SCM. Replace
any media that was removed in the process. Revegetate
disturbed areas immediately.
Water is standing more
Replace the top few inches of filter media and see if this corrects
than 5 days after a storm
the standing water problem. If so, revegetate immediately. If not,
event.
consult an appropriate professional for a more extensive repair.
Weeds and noxious plants
Remove the plants by hand or by wiping them with pesticide.
are growing in the
DO NOT SPRAY.
main treatment area.
The embankment
Shrubs or trees have
Remove shrubs or trees immediately.
started to grow on the
embankment.
An annual inspection by an
Make all needed repairs.
appropriate professional
shows that the
embankment needs repair.
The outlet device
Clogging has occurred.
Clean out the outlet device. Dispose of the sediment off -site.
The outlet device is
Repair or replace the outlet device.
damaged
The receiving water
Erosion or other signs of
Contact the local NC DEQ Regional Office.
damage have occurred at
the outlet.
9 1 P a g e

Permeable Pavement Maintenance Requirements
Important Maintenance Procedures:
At all times, the pavement shall be kept free of:
- Debris and particulate matter through frequent blowing that removes such debris, particularly during the
fall and spring.
- Piles of soil, sand, mulch, building materials or other materials that could deposit particulates on the pavement.
- Piles of snow and ice.
- Chemicals of all kinds, including deicers.
The permeable pavement will be inspected once a quarter. Records of operation and maintenance will be kept in a known set
location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are found
shall be repaired immediately.
SCM element:
Potential problem:
How to remediate the problem:
The entire SCM
Trash/debris is present.
Remove the trash/debris.
The perimeter of
Areas of bare soil
Regrade the soil if necessary to remove the gully, then plant
the permeable
and/or erosive gullies
groundcover and water until established.
pavement
A vegetated area
Regrade the area so that it drains away from the pavement, then
drains toward the
plant ground cover and water until established.
pavement.
The inlet device
The pipe is clogged.
Unclog the pipe. Dispose of the sediment off -site.
The pipe is cracked
Replace the pipe.
orotherwise
damaged.
Erosion is occurring in
Regrade the swale if necessary to smooth it over and provide
the swale.
erosion control devices such as reinforced turf matting or riprap to
avoid future problems with erosion.
Stone verge is clogged or
Remove sediment and replace with clean stone.
covered in sediment.
The surface of the
Trash/debris present
Remove the trash/debris.
permeable
Weeds
Do not pull the weeds (may pull out media as well). Spray them
pavement
with asystemic herbicide such as glyphosate and then return within
the week to remove them by hand. (Another option is to pour
boiling water on them or steam them.)
Sediment
Vacuum sweep the pavement.
Rutting, cracking or
Consult an appropriate professional.
slumping or damaged
structure
Observation well
Water present more than 5
Clean out clogged underdrain pipes. Consult an
days after a storm event
appropriate professional for clogged soil subgrade.
Educational sign
Missing or is damaged.
Replace the sign.
The outlet device
Clogging has occurred.
Clean out the outlet device. Dispose of the sediment off -site.
The outlet device is
Repair or replace the outlet device.
damaged
The receiving water
Erosion or other signs of
Contact the local NC DEQ Regional Office.
damage have occurred at
the outlet.
101Page

Sand Filter Maintenance Requirements
Important maintenance procedures:
- The drainage area will be carefully managed to reduce the sediment load to the sand filter.
- The sedimentation chamber or forebay will be cleaned out whenever sediment depth exceeds six inches.
- Once a year, sand media will be skimmed.
- The sand filter media will be replaced whenever it fails to function properly after maintenance.
The sand filter shall be inspected annually and within 24 hours after every storm event greater than 1.0 inches. Records
of operation and maintenance will be kept in a known set location and will be available upon request. Inspection activities shall
be performed as follows. Any problems that are found shall be repaired immediately.
SCM element:
Potential problem:
How to remediate the problem:
Entire SCM
Trash/debris is present.
Remove the trash/debris.
Adjacent pavement (if
Sediment is present on the
Sweep or vacuum the sediment as soon as possible.
applicable)
pavement surface.
Perimeter of sand filter
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, and then plant a
erosive gullies have formed.
ground cover and water until it is established. Provide lime and a one-
time fertilizer application.
Vegetation is too short or too
Maintain vegetation at an appropriate height (> 3").
long.
Flow diversion structure
The structure is clogged.
Unclog the conveyance and dispose of any sediment offsite.
The structure is damaged.
Make any necessary repairs or replace if damage is too large for
repair.
The inlet device
The pipe is clogged.
Unclog the pipe. Dispose of the sediment off -site.
The pipe is cracked or
Replace the pipe.
otherwise damaged.
Erosion is occurring in the
Regrade the swale if necessary to smooth it over and provide erosion
swale.
control devices such as reinforced turf matting or riprap to avoid future
problems with erosion.
Stone verge is clogged or
Remove sediment and replace with clean stone.
covered in sediment.
Forebay or pretreatment
Sediment has accumulated to
Search for the source of the sediment and remedy the problem if
area
a depth of greater than six
possible. Remove the sediment and stabilize or dispose of it in a
inches.
location where it will not cause impacts to streams or the SCM.
Erosion has occurred.
Provide additional erosion protection such as reinforced turf matting or
riprap if needed to prevent future erosion problems.
Weeds are present.
Remove the weeds, preferably by hand. If a pesticide is used, wipe it
on the plants. DO NOT SPRAY.
Filter bed and underdrain
Water is ponding on the
Check to see if the collector system is clogged and flush if necessary.
collection system
surface for more than 24
If water still ponds, remove the top few inches of filter bed media and
hours after a storm.
replace. If water still ponds, then consult an expert.
The outlet device
Clogging has occurred.
Clean out the outlet device. Dispose of the sediment off -site.
The outlet device is damaged
Repair or replace the outlet device.
The receiving water
Erosion or other signs of
Contact the local NC DEQ Regional Office.
damage have occurred at
the outlet.
111Page

Stormwater Wetland Maintenance Requirements
Important maintenance procedures:
- Immediately following construction of the stormwater wetland, bi-weekly inspections will be
conducted andwetland plants will be watered bi-weekly until vegetation becomes established
(commonly six weeks).
- No portion of the stormwater wetland will be fertilized after the first initial fertilization that is required to
establish thewetland plants.
- Stable groundcover will be maintained in the drainage area to reduce the sediment load to the wetland.
- Once a year, a dam safety expert should inspect the embankment.
After the stormwater wetland is established, it shall be inspected monthly and within 24 hours after every storm
event greater than 1.0 inches. Records of operation and maintenance will be kept in a known set location and will be
available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be
repaired immediately.
SCM element:
Potential problem:
How I will remediate the problem:
Entire SCM
Trash/debris is present.
Remove the trash/debris.
The perimeter of the SCM
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, and then plant a
erosive gullies have
ground cover and water until it is established. Provide lime and a
formed.
one-time fertilizer application.
Vegetation is too short or
Maintain vegetation at a height of approximately six inches.
too long.
Forebay
Sediment has accumulated
Search for the source of the sediment and remedy the problem if
in the forebay to a depth that
possible. Remove the sediment and dispose of it in a location
inhibits the forebay from
where it will not cause impacts to streams or the SCM.
Erosion has occurred.
Provide additional erosion protection such as reinforced turf
matting or riprap if needed to prevent future erosion problems.
Weeds are present.
Remove the weeds, preferably by hand. If pesticide is used,
wipe it on the plants. DO NOT SPRAY.
The inlet device
The pipe is clogged.
Unclog the pipe. Dispose of the sediment off -site.
The pipe is cracked
Replace the pipe.
or otherwise
damaged.
Erosion is occurring in
Regrade the swale if necessary to smooth it over and provide
the swale.
erosion control devices such as reinforced turf matting or riprap to
avoid future problems with erosion.
Stone verge is clogged or
Remove sediment and replace with clean stone.
covered in sediment.
121Page

Stormwater Wetland Maintenance Requirements (Continued)
Deep pool,
Algal growth covers over 50%
Consult a professional to remove and control the algal growth.
shallow waterand
of the deep pool and shallow
shallow land
water areas.
areas
Cattails, phragmites or other
invasive plants cover 50% ofthe
Remove invasive species by physical removal or by wiping
them with pesticides (do not spray) — consult a
deep pool and shallow
professional.
Shallow land remains flooded
Unclog the outlet device immediately.
more than 5 days after a
storm event.
Plants are dead, diseased or
Determine the source of the problem: soils, hydrology, disease,
dying.
etc. Remedy the problem and replace plants. Provide a one-time
fertilizer application to establish the ground cover if necessary.
Sediment has accumulated
Search for the source of the sediment and remedy the problem if
and reduced the depth to 75% of
possible. Remove the sediment and dispose of it in a location
the original design
where it will not cause impacts to streams or the SCM.
Best professional practices show
Prune according to best professional practices.
that pruning is needed
to maintain optimal planthealth.
Embankment
A tree has started to grow on the
Consult a dam safety specialist to remove the tree.
embankment.
An annual inspection by
Make all needed repairs
appropriate professional shows
that the embankment
Evidence of muskrat or beaver
Consult a professional to remove muskrats or beavers
activity is present.
Micro pool
Sediment has accumulated
Search for the source of the sediment and remedy the problem if
and reduced the depth to 75% of
possible. Remove the sediment and dispose of it in a location
the original design
where it will not cause impacts to streams or the SCM.
The outlet device
Clogging has occurred.
Clean out the outlet device. Dispose of the sediment off -site.
The outlet device is damaged
Repair or replace the outlet device.
The receiving water
Erosion or other signs of
Contact the local NC DEQ Regional office.
damage have occurred at the
outlet.
131Page

Wet Detention Pond Maintenance Requirements
The wet detention basin system is defined as the wet detention basin, pretreatment including forebays and the vegetated
filter if one is provided.
Important maintenance procedures:
- Immediately after the wet detention basin is established, the plants on the vegetated shelf and
perimeter of the basin should be watered twice weekly if needed, until the plants become established
(commonly six weeks).
- The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and notreadily penetrate into accumulated sediments.
- No portion of the wet detention pond should be fertilized after the first initial fertilization that is
required to establish the plants on the vegetated shelf.
- Stable groundcover should be maintained in the drainage area to reduce the sediment load to the wet
detention basin.
- 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.
- Once a year, a dam safety expert should inspect the embankment.
After the wet detention pond is established, it should be inspected annually. Records of operation and maintenance should be
kept in a known set location and must be available upon request. Inspection activities shall be performed as follows. Any
problems that are found shall be repaired immediately.
SCM element:
Potential problem:
How I will remediate the problem:
The entire SCM
Trash/debris is present.
Remove the trash/debris.
The perimeter of the SCM
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, and then plant a
erosive gullies have
ground cover and water until it is established. Provide lime and a
formed.
one-time fertilizer application.
Vegetation is too short or
Maintain vegetation at a height of approximately six inches.
too long.
The inlet device
The pipe is clogged.
Unclog the pipe. Dispose of the sediment off -site.
The pipe is cracked
Replace the pipe.
or otherwise
damaged.
Erosion is occurring in
Regrade the swale if necessary to smooth it over and provide
the swale.
erosion control devices such as reinforced turf matting or riprap to
avoid future problems with erosion.
Stone verge is clogged or
Remove sediment and replace with clean stone.
covered in sediment.
The forebay
Sediment has accumulated
Search for the source of the sediment and remedy the problem if
to a depth greater than the
possible. Remove the sediment and dispose of it in a location
original design depth
where it will not cause impacts to streams or the SCM.
for sediment storage.
Erosion has occurred.
Provide additional erosion protection such as reinforced turf
matting or riprap if needed to prevent future erosion problems.
Weeds are present.
Remove the weeds, preferably by hand. If pesticide is used,
wipe it on the plants. DO NOT SPRAY.
The vegetated shelf
Best professional practices
Prune according to best professional practices
show that pruning is needed
to maintain optimal plant
health.
Plants are dead, diseased or
Determine the source of the problem: soils, hydrology, disease, etc.
dying.
Remedy the problem and replace plants. Provide a one-time fertilizer
application to establish the ground cover if a soil test indicates it is
necessary.
Weeds are present.
Remove the weeds, preferably by hand. If pesticide is used,
wipe it on the plants. DO NOT SPRAY.
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Wet Detention Pond Maintenance Requirements (Continued)
The main treatment area
Sediment has accumulated to
Search for the source of the sediment and remedy the problem if
a depth greater than the
possible. Remove the sediment and dispose of it in a location where
original design sediment
it will not cause impacts to streams or the SCM.
storage depth.
Algal growth covers over 50%
Consult a professional to remove and control the algal growth.
of the area.
Cattails, phragmites or other
Remove the plants by wiping them with pesticide.DO NOT SPRAY.
invasive plants cover 50% of
the basin surface.
The embankment
Shrubs have started to grow
Remove shrubs immediately.
on the embankment.
Evidence of muskrat or
Consult a professional to remove muskrats or beavers.
beaver activity is present.
A tree has started to grow on
Consult a dam safety specialist to remove the tree.
the embankment.
An annual inspection by an
Make all needed repairs.
appropriate professional
shows that the embankment
needs repair.
The outlet device
Clogging has occurred.
Clean out the outlet device. Dispose of the sediment off -site.
The outlet device is damaged
Repair or replace the outlet device.
The receiving water
Erosion or other signs of
Contact the local NC DEQ Regional Office.
damage have occurred at the
outlet.
151Page

Important operation and maintenance procedures:
- The plants will be watered during extended periods of dry weather.
- Fertilize only once per year as long as the rooftop runoff system is not intended for nutrient removal.
The rooftop runoff management system will be inspected once a quarter and within 24 hours after every storm event greater
than 1.0 inches. Records of operation and maintenance will be kept in a known set locationand will be available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately.
SCM Element
Potential problem:
How to remediate the problem:
The plants materials
Weeds are present.
Remove the weeds by hand.
Vegetation is dead or
diseased.
Try to determine the cause of the problem (may wish to consult an
expert). Correct the problem and replace the plants.
The flow diversion
structure
The structure is clogged.
Unclog the conveyance and dispose of any sediment off -site.
The structure is damaged.
Make any necessary repairs or replace if damage is too large for
repair.
Gutters, drains and
spouts
Clogging has occurred.
Remove leaves, debris, and other foreign matter and dispose of in a
manner that will not impact streams or the SCM.
Damage has occurred.
Repair or replace the damaged conveyances.
161Page

Important operation and maintenance procedures:
- The roof area will be maintained to reduce the debris and sediment load to the system. Excess debris can
clog the system and lead to bypass of the design storm, and reduced reuse volume.
- To ensure proper operation as designed, a licensed Professional Engineer, Landscape Architect, or
other qualified professional will inspect the system annually.
- The system components will be repaired or replaced whenever they fail to function properly.
- If the outlet is metered, use must be recorded at a minimum of monthly. These records shall be kept on site
For inspection by DWQ.
The system will be inspected by the owner/operator at least annually. Records of operation and maintenance will be kept in a
known set location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are
found shall be repaired immediately. Inspection activities shall be performed as follows. Any problems that are found shall be
repaired immediately.
SCM element:
Potential problem:
How to remediate the problem:
The entire system
A component of the system is
Make any necessary repairs or replace if damage is too large for
damaged or leaking.
repair.
Water is flowing out of the
Check system for clogging and damage. Repair as needed so the
overflow pipe during a design
design volume is stored properly without discharging during a design
rainfall or smaller (usually a 1"
storm.
Check that the pump is operating properly and that the water is
or 1.5" rainfall).
actually being used at the volume designed.
If it is still not operating properly, then consult an expert.
The captured roof area
Excess debris or sediment is
Remove the debris or sediment as soon as possible.
present on the rooftop.
The gutter system
Gutters are clogged, or water
Unclog and remove debris. May need to install gutter screens to
is backing up out of the gutter
prevent future clogging.
system.
Rooftop runoff not making it
Correct the positioning or installation of gutters. Replace if necessary
into gutter system.
to capture the roof runoff.
The pump
Pump is not operating
Check to see if the system is clogged and flush if necessary. If it is
properly.
still not operating, then consult an expert.
The overflow pipe
Erosion is evident at the
Stabilize immediately.
overflow discharge point.
The overflow pipe is clogged.
Unclog or replace if it cannot be unclogged.
The outflow pipe is damaged.
Repair or replace the pipe.
The secondary water
Not operating properly.
Consult an expert.
The cistern
Sediment accumulation of 5%
Remove sediment.
or more of the design volume.
Algae growth is present inside
Do not allow sunlight to penetrate the cistern. Treat the water to
the cistern.
remove/prevent algae.
Mosquitoes in the cistern.
Check screens for damage and repair/replace. Treat with 'mosquito
dunks' if necessary.
The screens and filters
Debris and/or sediment has
Search for the source of the debris/sediment and remedy the problem
accumulated. Screens and
if possible. Clean/clear debris/sediment from screen or filter. Replace
filters are clogged.
if it cannot be cleaned.
ATTACH MANUFACTURER'S MAINTENANCE MANUAL FOR ALL PROPRIETARY DEVICES
171Page