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OPERATIONS & MAINTENANCE MANUAL
STORMWATER CONTROL STRUCTURE
BIO-RETENTION AREA
Owner(s): Town of Fuquay Varina Public Service Center
Address: 1415 Holland Road, Fuquay-Varina, NC 27526
Phone Number: 919-552-1402
Site/Subdivision Plan # N/A
Prepared by: TOFV En ing eering Department
Receiving Water Course: UT to Neuse
Date: 8/29/ 16
Date Constructed: August 2016, updated December 2019
OPERATIONS AND MAINTENANCE MANUAL
PROJECT NAME: TOFV Public Service Center
BIO-RETENTION AREA
This manual establishes procedures for maintenance and operation of the TOFV Public Service
Center Bio-retention area (s) in accordance with the Town of Fuquay-Varina's Land
Development Ordinance as set forth in Section 9-1405(e) MAINTENANCE.
MAINTENANCE OF BIO-RETENTION AREAS
Vegetation —The drainage areas have a ground cover of warm season grasses or fescue, which if
properly maintained will prevent erosion of the embankment and provide an easy surface for
inspection. The grass will be most difficult to obtain in the area subject to water level
fluctuation.
Re -Seeding —Periodic re -seeding may be required to establish grass on areas where seed did not
take or has been destroyed. Before seeding, a one-time fertilizer application (12-12-12) should
be applied at a minimum rate of 12 to 15 pounds per 1,000 SF. The seed should be evenly sown
at a rate of three pounds per 1,000 SF. The seed should be covered with soil to the depth of
approximately 1/4". Immediately following the planting, the area should be mulched with straw
and tacked.
Trees and Shrubs —Trees, shrubs and other landscape vegetation should be permitted only as
shown on the approved planting plan. The vegetation should be kept healthy and vibrant. If a
tree or shrub dies it should be removed and replaced with another tree or shrub from the same
species (attach plant list).
Mowing —Grass mowing, brush cutting and removal of weed vegetation will be necessary for
proper maintenance. All area slopes and vegetation should be mowed when the grass exceeds 8"
in height. Acceptable methods include the use of weed whips or power brush cutters and
mowers.
Erosion —Erosion occurs when the water concentrates causing failure of the vegetation or when
vegetation dies and sets up the environment for rill erosion and eventually gullies from the
stormwater runoff. All areas should be inspected. Proper care of vegetative areas that develop
erosion is required to prevent more serious damage to the site. Rills and gullies should be filled
with suitable soil compacted and then seeded. Methods described earlier on vegetation should be
used to properly establish a grass surface. Where eroded areas are detected, the cause of the
erosion should be addressed to prevent a continued maintenance problem. Frequently, problems
result from the concentration of runoff to one point of the bio-retention area instead of a uniform
distribution of runoff usually on slopes and at the inflow points. This can be corrected by
reshaping, to more evenly distribute runoff to areas not experiencing erosion problems.
Rodent Control —Generally in an urban environment, rodents are not a problem. Rodents such
as groundhogs, muskrats and moles are attracted to moist, wet areas and can be quite dangerous
to the structural integrity and proper performance of the earthwork and drainage. Groundhogs
and muskrats thrive on burrowing into the manmade earthwork, which become pathways for
seepage. In the event that burrows are detected within the bio-retention area, the rodents should
be dealt with by removal.
Trash and Debris —Trash acts as a barrier to stormwater infiltration and attracts unwanted pests.
The bio-retention area should be kept clear of debris such as loose bottles, cans, food containers
and other forms of rubbish. The area should be cleared of debris as needed.
MAINTENANCE OF SPILLWAYS AND CONTROL STRUCTURE
Inspection of Conduits —Conduits should be inspected thoroughly once a year. Conduits should
be visually inspected at the joints. Pipes should be inspected for proper alignment (sagging),
elongation and displacement at joints, cracks, leaks, surface wear, loss of protective coating,
corrosion and blocking. Problems with conduits most often occur at joints and special attention
should be given to them during inspection. Joints should be checked for gaps caused by
elongation or settlement and loss of joint filler material. Open joints can permit erosion of the
earthwork and possibly the piping of soil material through the joints. A depression in the soil
surface over the pipe may be signs that soil is being removed from around the pipe. The
underdrains should be inspected to ensure that they are functional and allowing the bioretention
area to drain.
OPERATION
Record Keeping —Operation of the bio-retention area should include recording of the following:
Annual Inspection ReportsA collection of written inspection reports should be kept on record.
Inspection by a qualified professional is required annually. Copies should be provided to the
Town of Fuquay-Varina's Engineering Department on the approved form.
Observations —All observations should be recorded.
Maintenance —Written records of maintenance and/or repairs should be recorded.
FA
Other Operational Procedures —The owner should maintain a complete and up-to-date set of
plans (as -built drawings) and all changes made to the bio-retention area over time should be
recorded on the as-builts. Do not pile snow on top of the bioretention area.
Sedimentation and Dredging —Sedimentation from on -site and off -site soils will eventually
result in the clogging of drainage conduits and will have to be removed. The frequency of this
sediment removal can be reduced by ensuring that the site areas around the building are
stabilized with a vegetative ground cover such that it restrains erosion. Do not drive heavy
equipment into the bioretention area. Remove and replace vegetation, sediment, mulch, etc. by
hand or have equipment that can reach from the edge of bioretention area.
Example Maintenance Schedule for Bio-retention Areas
Description
Method
Frequency
Time of year
SOIL
Inspect and repair erosion
Visual
Monthly
All year
ORGANIC LAYER
Remulch any void area
By hand
As needed
As needed
Remove previous mulch layer
By hand
Once every
Spring
before applying new layer
2-3 years
(optional)
Any additional mulch added
By hand
As needed
As needed
PLANTS
Removal and replacement of
See planting
Twice a year
As directed by
all dead and diseased
specifications
landscaper
vegetation considered beyond
treatment
Treat all diseased trees
Mechanical or
N/A
Varies, dependent
and shrubs
by hand
on insect or disease
infestation
Removal of cattails and other
By hand or
As needed
As needed
invasive species
through hand
application of
herbicide
Watering of plant material
By hand
Daily
Immediately after
shall take place at the end of
completion of project
each day for fourteen
consecutive days and after
planting is completed
Remove support stakes and
By hand
As needed
As needed
wires within 6 months of
establishment
Detail of Planting Guide for each Bio-Retention Basin Included
BIO-RETENTION INSPECTION CHECKLIST
(Project Name):
Date:
Time:
3
Check/Circle Observations Action Action Action
Condition Noted Repair Monitor Investigative
U/S Sloe
Type:
Vegetation/Riprap
Rodent burrows
Crest
Type:
Ruts/erosion
Cracks/settlement
Poor alignment
D/S Sloe
Type:
Vegetation/erosion
Rodent burrows
Sloughs/slides/cracks
Seepage/wetness
Pool
Type:
Ground cover
Sedimentation
Abutment
Type:
Vegetation/erosion
Slough/slides/cracks
Seepage/wetness
General Comments, Sketches & Field Measurements
PERODIC INSPECTION, OPERATION & MAINTENANCE RECORDS
(Project Name):
E!t1E!t1L!t]-Conditions1F
Weather General Observations or �!n
Comments
Date Maintenance Performed Comments Recorded
By
Date Equipment Operated Comments Recorded
By