HomeMy WebLinkAboutSW3201003_SAND FILTER MAINTENANCE REQUIREMENTS_20201103Sand Filter Maintenance Requirements
Important operation and maintenance procedures:
- Manage the drainage area to reduce the sediment load to the sand filter.
- Clean out the sedimentation chamber or forebay whenever sediment depth exceeds six inches.
- At least once a year, skim the sand media
- Replace the sand filter media whenever it fails to function properly after maintenance.
After the sand filter is established, it shall be inspected quarterly and within 24 hours after every storm event greater
than 1.0 inches (or 1.5 inches if in a Coastal County). 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.
CM element:
I
Potential problem:
How to remediate the problem:
ntire sand filter
Trash/debris is present.
Remove the trash/debris.
Adjacent pavement (if
Sediment is present on the
applicable)
pavement surface.
Sweep or vacuum the sediment as soon as possible.
Areas of bare soil and/or
Regrade the soil if necessary to remove the gully, plant ground
The perimeter of the sand
erosive gullies have
formed.
cover and water until it is established. Provide lime and a one -
filter
time fertilizer application.
Vegetation is too short or
too long.
Maintain vegetation at an appropriate height.
The flow diversion
The structure is clogged.
Unclog the structure and dispose of sediment in a location where
it will not cause impacts to streams or the SCM.
structure (if applicable)
The structure is damaged.
Make any necessary repairs or replace if the damage is too much
for repair.
The inlet pipe is clogged (if
Unclog the pipe and dispose of sediment in a location where it
applicable).
will not cause impacts to streams or the SCM.
The inlet pipe is cracked or
otherwise damaged (if
Repair or replace the pipe.
applicable).
The inlet device
Erosion is occurring in the
g Re rade the swale if necessary and provide erosion control
swale (if applicable).
devices such as reinforced turf matting or riprap to avoid future
problems with erosion.
Stone verge is clogged or
covered in sediment (if
Remove sediment and clogged stone and replace with clean
applicable).
stone.
Sediment has accumulated
Search for the source of the sediment and remedy the problem if
to
a depth of greater than
possible. Remove the sediment and dispose of it in a location
six inches.
where it will not cause impacts to streams or the SCM.
Sediment chamber
Erosion has occurred.
Provide additional erosion protection such as reinforced turf
(forebay)
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 rather than spraying.
Sand Filter Maintenanra Ranniramanfc /rrnnfin—rli
SCM element:
IPotential problem:
How to remediate the problem:
Sand chamber and
Water is ponding on the
Check to see if the collector system is clogged and flush if
underdrain collection
surface for more than 24
necessary. If water still ponds, remove the top few inches of filter
system
hours after a storm.
bed media and replace. If water still ponds, then consult an
appropriate professional.
Clogging has occurred.
Clean out the outlet device and dispose of sediment in a location
The outlet device
where it will not cause impacts to streams or the SCM.
The outlet device is
damaged.
Repair or replace the outlet device.
Erosion or other signs of
damage have occurred at
Repair the damage and improve the flow dissipation structure.
the outlet.
The receiving water
Discharges from the sand
filter are causing erosion or
sedimentation in the
Contact the local NCDEQ Regional Office.
receiving water.