SW1080103_O&M Agreement_20080605

Permit Number:
(to be provided by DWQ)
Drainage Area Number:
Wet Detention Basin Inspection and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
The wet detention basin system is defined as the wet detention basin,
pretreatment including forebays and the vegetated filter if one is provided.
This system (check one):
® does ❑ does not incorporate a vegetated filter at the outlet.
This system (check one):
❑ does ® does not incorporate pretreatment other than a forebay.
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).
— 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 once a month and
within 24 hours after every storm event greater than 1.0 inches (or 1.5 inches if in a
Coastal County). Records of inspection 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.
BMP element:
Potentialproblem:
How I will remediate theproblem:
The entire BMP
Trash/debris is present.
Remove the trash/debris.
The perimeter of the wet
Areas of bare soil and/or
Regrade the soil if necessary to
detention basin
erosive gullies have formed.
remove the gully, and then plant a
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 a height of
long.
approximately six inches.
Form SW401-Wet Detention Basin I&M-Rev.2

Permit Number:
(to be provided by DWQ)
Drainage Area Number:
BMP element:
Potentialproblem:
How I will remediate theproblem:
The inlet device: pipe or
The pipe is clogged.
Unclog the pipe. Dispose of the
Swale
sediment off -site.
The pipe is cracked or
Replace the pipe.
otherwise damaged.
Erosion is occurring in the
Regrade the Swale if necessary to
Swale.
smooth it over and provide erosion
control devices such as reinforced
turf matting or riprap to avoid
future problems with erosion.
The forebay
Sediment has accumulated to
Search for the source of the
a depth greater than the
sediment and remedy the problem if
original design depth for
sediment storage.
possible. Remove the sediment and
dispose of it in a location where it
will not cause impacts to streams or
the BMP.
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 rather than spraying.
The vegetated shelf
Best professional practices
Prune according to best professional
show that pruning is needed
practices
to maintain optimal plant
health.
Plants are dead, diseased or
Determine the source of the
dying.
problem: soils, hydrology, disease,
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.
Weeds are present.
Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
the plants rather than spraying.
The main treatment area
Sediment has accumulated to
Search for the source of the
a depth greater than the
sediment and remedy the problem if
original design sediment
possible. Remove the sediment and
storage depth,
dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Algal growth covers over
Consult a professional to remove
50 %, of the area.
and control the algal growth.
Cattails, phragmites or other
Remove the plants by wiping them
invasive plants cover 50% of
with pesticide (do not spray).
the basin surface.
Form SW401-Wet Detention Basin I&M-Rev.2

Permit Number:
(to be provided by DWQ)
Drainage Area Number:
BMP element:
Potentialproblem:
How I will remediate theproblem:
The embankment
Shrubs have started to grow
Remove shrubs immediately.
on the embankment.
Evidence of muskrat or
Use traps to remove muskrats and
beaver activity is present.
consult a professional to remove
beavers.
A tree has started to grow on
Consult a dam safety specialist to
the embankment.
remove the tree.
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
I Repair or replace the outlet device.
The receiving water
Erosion or other signs of
Contact the local NC Division of
damage have occurred at the
Water Quality Regional Office, or
outlet.
the 401 Oversight Unit at 919-733-
1756.
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.
When the permanent pool depth reads 2173 feet in the main pond, the
sediment shall be removed.
When the permanent pool depth reads 2173 feet in the forebay, the sediment
shall be removed.
Sediment Removal
Bottom
BASIN DIAGRAM
(fill in the blanks)
Permanent Pool Elevation 2176
2173 Pe manen Pool
----------- -- Volume Sediment Removal Elevation 2173 Volume
2172 -ft Min. ---------------------------_--------------- ------
Sediment Bottom 1levation 2172 2 I-ft
Storage Sediniet
Storage
FOREBAY MAIN POND
Form SW401-Wet Detention Basin 1&M-Rev.2

Permit Number:
(to be provided b DWQ)
1 acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. 1 agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible patty.
Project nameMillandale Elementary School
BMP drainage area number:
Print name:
Title:Senior Director for Facilities of Henderson County Public Schools
Address:414 Fourth Avenue West
Note: The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president.
1, 0.Yz71 � N \� ,, a Notary Public for the State of
County of _gs Yna YS try , do hereby certify that
KCAW @ I l personally appeared before me this I`i
day of VJ , a and acknowledge the due execution of the
forgoing wet detention sin maintenance requirements. Witness my hand and official
seal,
SEAL
NOTARY
PUBLIC
My commission expires�l (1T
Form SW401-Wet Detention Basin I&M-Rev.2

Permit Number:
(to be provided by DWQ)
Drainage Area Number: ,l
Filter Strip, Restored Riparian Buffer and Level Spreader
Inspection and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
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 quarterly and within 24 hours
after every storm event greater than 1.0 inch (or 1.5 inches if in a Coastal County).
Records of inspection 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.
BMP element:
Potentialproblem:
How I will remediate theproblem:
The entire filter strip
Trash/debris is present.
Remove the trash/debris.
system
The flow splitter device
The Flow splitter device is
Unclog the conveyance and dispose
(if applicable)
clogged.
of any sediment off -site.
The flow splitter device is
Make any necessary repairs or
damaged.
replace if damage is too large for
repair.
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page 1 of 3

BMP element:
Potentialproblem:
How I will remediate theproblem:
The swale and the level
The Swale is clogged with
Remove the sediment and dispose
lip
sediment.
of it off -site.
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
end of the level spreader that
that is higher than the level lip, and
shows stormwater has
then plant a ground cover and
bypassed it.
water until it is established. Provide
lime and a one-time fertilizer
application.
Trees or shrubs have begun
Remove them.
to grow on the swale or just
downslo e of the level lip.
The bypass channel
Areas of bare soil and/or
Regrade the soil if necessary to
erosive gullies have formed.
remove the gully, and then
reestablish proper erosion control.
Turf reinforcement is
Study the site to see if a larger
damaged or ripap is rolling
bypass channel is needed (enlarge if
downhill.
necessary). After this, reestablish
the erosion control material.
The filter strip
Grass is too short or too long
Maintain grass at a height of
(if applicable).
approximately three to six inches.
Areas of bare soil and/or
Regrade the soil if necessary to
erosive gullies have formed.
remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Sediment is building up on
Remove the sediment and
the filter strip.
restabilize the soil with vegetation if
necessary. Provide lime and a one-
time fertilizer application.
Plants are desiccated.
Provide additional irrigation and
fertilizer as needed.
Plants are dead, diseased or
Determine the source of the
dying.
problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application.
Nuisance vegetation is
Remove vegetation by hand if
choking out desirable species.
possible. If pesticide is used, do not
allow it to get into the receiving
water.
The receiving water
Erosion or other signs of
Contact the NC Division of Water
damage have occurred at the
Quality local Regional Office, or the
outlet.
1 401 Oversight Unit at 919-733-1786.
Form SWU401-1-evel Spreader, Filler Strip, Restored Riparian Buffer I&M-Rev.2 page 2 of 3

Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project name:Hillandale Elementary School
BMP drainage area number:
Print name
Title:Senior Director for Facilities of Henderson County Public Schools
Address:414 Fourth Avenue West
Note: The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president.
I, 'f)�O Lm 1T'. Wa I �—P V , a Notary Public for the State of
�qe , County of ♦` e -pS d'Y\— , do hereby certify that
Q personally appeared before me this
day of at) o , and acknowledge the due execution of the
forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements.
Witness my hand and official seal,
P 84�C
SEAL
My commission expires I4a0I0q
Fonn SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer 1&M-Rev.2 Page 3 of 3

Grassed Swale
I will keep a maintenance recorc`�
log in a known set location. An
corrected, repaired or replaced in
of structures, saf et}' of the public,
Important maintenance procedures:
Pcrmit Name:
��(to be provided by DB'Q)
Drainage Area Number:
M,4 t ance Agreement
ti0
BMP e enance record will be kept in a
tints noted in the inspection will be
hose deficiencies can affect the integrity
e removal efficiency of the MCI.
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 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.
BMP element:
Potentialproblem:
How I will remediate theproblem:
The entire length of the
Trash/debris is present.
Remove the trash/debris.
Swale
Areas of bare soil and/or
Regrade the soil if necessary to
erosive gullies have formed.
remove the gully, and then re -sod
(or plant with other appropriate
species) and water until established.
Provide lime and a one-time
fertilizer application.
Sediment covers the grass at
Remove sediment and dispose in an
the bottom of the Swale.
area that will not impact streams or
BMPs. Re -sod if necessary.
Vegetation is too short or too
Maintain vegetation at a height of
long.
a . roximateiv six inches.
The receiving water
Erosion or other signs of
Contact the NC Division of Water
damage have occurred at the
Qualitv 401 Oversight Unit at 919-
outlet.
733-1786.
Form SW401-Grassed Swale O&M-Rev.3 Page I of 2

Permit Number:
(to he provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project nameMillandale Elementary School
BMP drainage area number:
Print
Title:Senior Director for Facilities of Henderson County Public Schools
Address:414 Fourth Avenue West
Note: The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president.
1,, ):E�4d9arr, CQSe Qt.,e a Notary Public for the State of
dIIO(U Qom, County of VAe_Kder'S4:s — do hereby certify that
CcD_ J,oe I I `� personally appeared before me this 2 ��
day of , ZODO, and acknowledge the due execution of the
forgoing grassed swale maintenance requirements. Witness my hand and official seal,
�;arbcvc,
SEAL
My commissionexpires�INJu„t 23, ZOI
Fornt SW401-Grassed Swale O&M-Rev3 Page 2 of 2