HomeMy WebLinkAboutSW1080104_O&M Agreement_20080507Permit Number:
(to be provided by DWQ)
Drainage Area Number: 1
Wet Detention Basin Inspection.and Maintenance Agreement
1 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:
Itriinediately'after the wef 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 fotuid shah
be repaired immediately.
BMP element:
Potential roblem:
How I will remediate the roble►n:
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 UWQ)
Drainage Area Number: I
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 damn ed.
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
possible. Remove the sediment and
sediment storage.
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
revent future erosion problems.
Weeds are present.
Remove the weeds, pzeferably by
hand. If pesticide is used, wipe it or.
the plant, 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_s era n- .
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 sedinicnt and
storage depth.
I
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 rowth.
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: !t -
BMP element:
Potentialproblem:
How I will remediate the roblem:
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 darn 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
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-
1786.
The measufing 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 2099 feet in the main pond, the
sediment shall be removed.
When the permanent pool depth reads 2099 feet in the forebay, the sediment
shall be removed.
BASIN DIAGRAM
ill in the blanks)
0 Permanent Pool Elevation 210
Sediment Removal 2099 Pe maven Pool
-------------- -- Volume Sediment Removal Elevation 2099 Volnme
BottoEn Elevatio 2098 -ft Min.
--------------------------------
-
------ ---- - - -
Sediment Bottom Elevation 2098 I-ft n.
Storage Sediment
Storage
FOREBAY
MAIN POND
Form SW401-Wet Detention Basin I&M-Rev.2
Permit Number
(to be provided by DWQ)
1 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:Mills River Elementary School
BMP drainage area number: I
Print name:Bo Caldwell
Title:Senior Director for Facilities of Henderson County Public Schools
Address:414 Fourth Avenue West
PI
Si
Fol
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 11 Ck- a Notary Public for the State of
County of �i'eh[�@�SLry�, da hereby certify that
&W u personally appeared before me this 14
day of and acknowledge the due execution of the
forgoing wet detention basin maintenance requirements. Witness my hand and official
seal,
SEAL -
A1O
My commission expires lo1Ja 0
Form SW401-Wet Detention Basin I&M-Rev.2
Permit Number:
(to be provided by DWQ)
Drainage Area Number: I
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- optinvam pollutant
removal efficiency. Turf grass should not be cut shorter than 3 to 5 incl-:es and
may be allowed to grow as tall as 12 inches depending on EiLsthetic requirumerits
(NIPC,1993). Forested filter strips do not require.this type of Yr. aintenarice.
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 four:d shad
be repaired immediately.
BNW element:
Potentialproblem:
Howill remediate_thU_utst•!m:
The entire filter strip
Trash/debris is present.
Remove the trash/debris.
-system
The flow splitter device
(if applicable)
The flow splitter device is
clogged.
Unclog the conveyance and dispose
of any 1y sediment off. -site.
The flow splitter device is
Make any necessary repairs or
damaged.
replace .if dama e is tots large or
repair.
Forin SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev:2 Page 1 of 3
SMP element:
Potentialproblem-
blow t 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
4,..
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 than plant a
ground cover and water until it is
established.,vProvide 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.
401 Oversight Unit at 919-733-1786.
Form SWU401-Level Spreader, Filter 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:Ml Its Rarer Elementary School
BMP drainage area number: I
Print name:Bo Caldwell
Title:Senior Director for Facilities of Henderson County Public Schools _
Address:414 Fourth Avenue West
Phor
Sign
Date
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, �TY�+�crrl _ U� co 4- , a Notary Public for the State of
County off`� do hereby certify that
b QC0 @ ` personally appeared before me this I
day of _ G 09, and acknowledge the due execution of the
forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements.
Witness my hand and official seal,
N07A
PUPLIC
' '/�/llllllllilll�l
SEAL
My commission expire;
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer 1&M-Rev.2 Page 3 of 3
MIS '0've'-
Permit No
(to be provided by DWO)
ill!° REQUIREQ ITEMS CFIECKL1STr
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design.requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Pagel Plan
Initials Sheet No.
M —66 C4.OIGrading
C7.21Site Details
llqoL _ C4,9IGrading
C7.2/Site Details
1. Plans (1'- 50' or larger) of the entire site showing:
Design at ultimate build -out,
Off -site drainage (if applicable),
Delineated drainage basins (include Rational C coefficient per basin),
Basin dimensions,
Pretreatment system,
High flow bypass system,
Maintenance access,
Recorded drainage easement and public right of way (ROW),
Overflow device, and
Boundaries of drainage easement.
2. Partial plan (1" = 30' or larger) and details for the wet detention basin showing:
Outlet structure with trash rack or similar,
Maintenance access,
Permanent pool dimensions,
Forebay and main pond with hardened emergency spillway,
Basin cross-section,
Vegetation specification for planting shelf, and
Filter strip.
_/!20 f_ C7.2/Site Details 3. Section view of the dry detention basin (1" = 20' or larger) showing:
Side slopes, 3:1 or lower,
Pretreatment and treatment areas, and
Inlet and ouldet structures.
±"A6C7.3/General 4. If the basin is used for sediment and erosion control during construction, clean out of the basin is Specified
Notes on the plans prior to use as a wet detention basin.
alcbook 5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and far fcrabay,
;o verify volume provided.
C7_3/renerai 0. An assurance that the installed system will meet design specifications upon initial operation onco the
Notes project is complete and the entire drainage area is stabilized.
C7 'G�nar@I T A construction sequence that shows how the wet detention basin will be protected from sediment until t,1e
Notes entire drainage area is stabilized.
AJ t?p Calcbook 8. The supporting calculations.
_/ 9j�_ Attached 9. A copy of the signed and notarized inspection and maintenance (I&M) agreement.
NIA _ NIA _ 10. A copy of the deed restriction.
Form SW401-Wet Detention Hasin-Rev.1 Part lit. Required Items Checklist, Page 1 of 1
Permit Number:
(to be provided by DIVA)
Drainage Area Dumber:
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 Eldoes not incorporate a vegetated filter at the outlet.
This system (check one):
El does ® does not incorporate pretreatment other than a forebay.
Important maintenance procedures:
- - - =- Itnmediately"aftef 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 main tcrtance, thr
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 7.0 inc!nes (or 'I.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 shali
be repaired immediately.
BMP element:
Potentialproblem:
How I will remediate the rohie�r,:
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 them platit a
ground cover and witcr until i"t is
established. Provide lime and a
one-time fertilizer a licatior:.
Vegetation is too short or too
_ _
Maintain vegetation at a heigh+• of
long.
approximately six inches.
Form SW401-Wet Detention Basin I&M-Rev.2