Attachment G_Operation & Maintenance Plan_DRAFT_20230516

Prepared For: ����� LISS BATTLESHIP NORTH CAROLINA (BNC)
'iili 1 BATTLESHIP ROAD
HI BATTLESP .m.m. WILMINGTON, NORTH CAROLINA 28401
NORTH CAROLINA
USS BATTLESHIP NORTH CAROLINA
LIVING WITH WATER IMPROVEMENTS
WILMINGTON, NORTH CAROLINA
OPERATION AND MAINTENANCE PLAN
MAY 16, 2023
NOT FOR CONSTRUCTION
Submitted By:
moffatt & nichol
4700 Falls of Neuse Road, Suite 300
Raleigh, North Carolina 27609
919-781-4626
M&N Project No. 10258-02
NC Firm License No. F-0105

USS Battleship North Carolina 05.16.2023
Living with Water Improvements Operation and Maintenance Plan
SCO ID No. 20-21601-02A M&N Project No. 10258-02
TABLE OF CONTENTS
Attachments:
Title Sheet
Table of Contents
Exhibit 1— Clean Water Management Trust Fund Form
Exhibit A — BMP Layout Map
Exhibit B — Battleship Stormwater Operation and Maintenance Manual
Table of Contents Page 1 of 1

EXHIBIT 1
CWMTF STORMWATER BMP OPERATION AND MAINTENANCE PLAN FORM
NC CLEAN WATER MANAGEMENT TRUST FUND
STORMWATER BMP OPERATION AND MAINENANCE PLAN BMP O&M PLAN
Submit to CWMTF a BMP O&M Plan for each stormwater BMP described in the Scope of
Work of Exhibit A for which CWMTF funds are used for construction and a local government
commits to maintain the BMP for at least 10 years.
CWMTF Project No.: 2019-410
Project Name / Description: USS Battleship North Carolina Living with Water Improvements
CWMTF Grant Recipient: USS Battleship North Carolina
Grant Recipient Primary Contact: Mr. Christopher Vargo
Address: 1 Battleship Road, Wilmington, North Carolina 28401
Phone No.: 910-399-9103
Email: [e-mail]
Date of BMP O&M Plan: 05/03/2023
Local Government Committing to BMP Maintenance: USS Battleship North Carolina / DNCR
BMP O&M Plan Prepared by: Moffatt & Nichol
Affiliation: Consulting Engineer
Address: 4700 Falls ofNeuse Road, Suite 300, Raleigh, North Carolina 27609
Phone No.: 984-239-2797
Email: josemartinezkmoffattnichol.com
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CWMTF Project No. 2019-410

Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: BMP No.01— (6) locations around the stormwater wetland area as seen in
Exhibit A
Type of BMP: Riprap Inlet Areas
Summary Description of the BMP and its Components: Riprap inlets for stormwater flow away
from parking areas into wetland area.
BMP Footprint Area (sq. ft): 425
Has this BMP Been Constructed?: No
Projected Construction Completion Date: July 2024
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The Riprap Inlet Areas are designed as sediment / debris filters and energy dissipators for
stormwater runoff flowing from the parking areas to the wetland area
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and documented.
- Document all inspections
- Excessive sediment buildup on the riprap and adjacent areas shall be removed
- Displaced rock shall be replaced with larger rock in open areas
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Trash and Debris
Inlets are blocked by
Remove debris and trash
Quarterly and after
debris
and dispose offsite
major storm events
Sediment accumulation
Sediment buildup on
###
Quarterly and after
in riprap
riprap or surround areas
major storm events
blocking flow
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
When the excessive sediment accumulation occurs, it is recommended that the source of the sediment
be identified and addressed to avoid need for future sediment removal
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance, and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
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Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: Discharge BMP No.02 — Within fencing near center of parking area
Type of BMP: Main Stormwater Wetland Area
Summary Description of the BMP and its Components: Wetland area consisting of grassy areas
and native plants.
BMP Footprint Area (sq. ft): 20,000
Has this BMP Been Constructed?: No
Projected/Actual Construction Completion Date: July 2024
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The Main Stormwater Wetland Area is designed to store stormwater from the adjacent areas allowing
for drainage into the tidal creek which reduces flood rates.
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and documented.
- Document all inspections
- Observe area for invasive species and maintenance as applicable
- Observe area for plant health, replanting areas with dead or unhealthy plants annually
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Trash and Debris
Debris present at inlets
Remove debris and trash
Quarterly and after
/ wetland areas
and dispose offsite
major storm events
Sediment accumulation
Excessive sediment
Remove sediment in
Quarterly and after
in wetland area
accumulation (Visibly
targeted areas
major storm events
reduced volume for
stormwater storage)
Sediment accumulation
Sediment accumulation
Remove sediment
Quarterly and after
near drawdown pipe
blocking drawdown
around inlet of
major storm events
pipe inlet
drawdown pipe
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
When low plant success is observed during inspection, maintenance should be provided involving
replanting distressed areas with species of like kind.
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance, and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
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CWMTF Project No. 2019-410

Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: BMP No.03 — Located near West border of Stormwater Wetland Area
Type of BMP: Low Flow Drawdown Pipe
Summary Description of the BMP and its Components: Drawdown pipe for water quality
BMP Footprint Area: N/A
Has this BMP Been Constructed?: No
Projected/Actual Construction Completion Date: July 2024
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The low flow drawdown pipe is designed to control the oversupply / water rise within the project area
to mitigate damage to newly planted vegetation and maintains water quality.
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and
documented.
- Document all inspections
- What is the condition of the pipe and cap?
- Is the water flowing through the desired opening or bypassing/backup?
- Each site should be evaluated individually based on potential influent material and removal
rates
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Trash and Debris
Inlets and outlets are
Remove debris and trash
Quarterly and after
clogged with debris
and dispose offsite
major storm events
Sediment accumulation
Sediment accumulation
Remove sediment to
Quarterly and after
at pipe opening
at pipe inlet/outlet
allow for waterflow
major storm events
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
When the low flow drawdown pipe or cap appears damaged and is affecting waterflow, maintenance
shall involve replacement of damaged parts with appropriate materials.
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
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Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: BMP No.04 — Same as Drawdown Pipe (Near riser structure West of
stormwater wetland area)
Type of BMP: Maintenance Valve
Summary Description of the BMP and its Components: Maintenance Drain and Valve for pipe
BMP Footprint Area: N/A
Has this BMP Been Constructed?: No
Projected/Actual Construction Completion Date: July 2024
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The Maintenance Valve is designed for conducting maintenance / drainage for the low -flow drawdown
pipe.
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and documented.
- Document all inspections
- Valve / Drainage functioning properly?
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Open Plug Valve to
Valve blockage
Report any damage or
Quarterly and after
ensure proper function
valve blockage
major storm events
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
When the maintenance valve does not function properly, report findings to the Owner for how to
approach maintenance.
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance, and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
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CWMTF Project No. 2019-410

Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: BMP No.05 — West of the Stormwater Wetland Area connecting to the
drawdown pipe
Type of BMP: Riser Structure
Summary Description of the BMP and its Components: Riser structure for pipe connections (with
attached trash rack)
BMP Footprint Area (sq. ft): 40
Has this BMP Been Constructed?: No
Projected/Actual Construction Completion Date: July 2024
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The Riser Structure is designed provide protection for pipe connections from sediment blockage and
floating debris, provide additional storage for stormwater while it is flowing into the spillway pipe.
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and documented.
- Document all inspections
- What is the condition of the structure, trash rack, and pipe connections? Leaks resent?
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Trash and Debris
Trash rack clogged
Remove debris and trash
Quarterly and after
with debris
and dispose offsite
major storm events
Sediment accumulation
Complete or partial
Remove sediment from
Quarterly and after
in riser
pipe blockage
i e openings
major storm events
Leakage observation
Leaks present
Seal all locations
Quarterly and after
major storm events
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
Seal any leaks at the pipe connections or elsewhere to avoid damage to the surrounding wetland
vegetation.
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance, and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
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CWMTF Project No. 2019-410

Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: Discharge BMP No.06 — Near West border of main parking area
(underground)
Type of BMP: Principal Spillway Pipe (PSP)
Summary Description of the BMP and its Components: Spillway pipe for stormwater flow into
outlet area
BMP Footprint Area: N/A
Has this BMP Been Constructed?: No
Projected/Actual Construction Completion Date: July 2024
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The PSP is designed to serve as the primary outlet for storm flow for the entirety of the project site.
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and
documented.
- Document all inspections
- What is the condition of the ground above the piping?
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Trash and Debris
Pipe inlets and outlets
Remove debris and trash
Quarterly and after
are clo ed with debris
and dispose offsite
major storm events
Sediment accumulation
Spillway fully or
Clear sediment to form
Quarterly and after
in spillway outlet
partially blocked by
flow path
major storm events
sediment
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
When cave-ins appear behind the riser structure, the owner shall contact the maintenance contractor or
inspector as soon as possible as the presence of such a condition may be indicative of some form of
piping failure, which can threaten the viability of the overlying pavement, the function of the PSP, and
the overall function of the wetland system.
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
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CWMTF Project No. 2019-410

Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: BMP No.07 — West end of spillway pipe
Type of BMP: Stormwater Wetland Outfall Riprap Pool
Summary Description of the BMP and its Components: Riprap pool at PSP outlet
BMP Footprint Area (sq. ft): 175
Has this BMP Been Constructed?: No
Projected/Actual Construction Completion Date: July 2024
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The Stormwater Wetland Outfall Riprap Pool is designed to reduce the rate of sediment erosion and
flow velocity at the Principal Spillway outfall.
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and
documented.
- Document all inspections
- What is the condition of the riprap? Undercutting Present?
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Trash and Debris
PSP outlets are clogged
Remove debris and trash
Quarterly and after
with debris
and dispose offsite
major storm events
Pipe / pipe joint
Damage / joint failure
Report findings to the
Quarterly and after
Owner
major storm events
Sediment accumulation
Excessive sediment /
Remove excess sediment
Quarterly and after
vegetation
/ vegetation from ri-prap
major storm events
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
The outlet rocks and the end of the rock outfall shall be monitored for scour and undercutting of rock.
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance, and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
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Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: BMP No.08 — Connected to the PSP outfall at the West end
Type of BMP: Flap Gate
Summary Description of the BMP and its Components: Flap Gate with hinge and openings
BMP Footprint Area: N/A
Has this BMP Been Constructed?: No
Projected/Actual Construction Completion Date: July 2024
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The Flap Gate is designed to allow for one-way water flow from the adjacent pipe into the outlet area
without allowing water to flow back into the pipe. Occurs when emptying stormwater storage from
stormwater wetland area.
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and documented.
- Document all inspections
- Flap gate blocked or not allowing water to flow from PSP?
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Trash and Debris
Flap gate blocked by
Remove debris and trash
Quarterly and after
debris
and dispose offsite
major storm events
Damage
Damage to flap gate or
Report findings to the
Quarterly and after
its connections
Owner
major storm events
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
When the Flap Gate has damage to its components that affect the ability for water to flow properly,
maintenance shall be performed to repair any damage and restore functionality to the gate.
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance, and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
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CWMTF Project No. 2019-410

Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: BMP No.09 — Area West of parking area (And any area around Tidal Creek)
Type of BMP: Main Tidal Wetland Area
Summary Description of the BMP and its Components: Vegetated wetland area
BMP Footprint Area (sq. ft): 100,000
Has this BMP Been Constructed?: No
Projected/Actual Construction Completion Date: July 2024
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The Main Tidal Wetland Area serves as the primary BMP for the site by providing storage for adjacent
water level rise and providing erosion control with native vegetation.
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and
documented.
- Document all inspections
- Observe wetland for areas of low plant success (areas with unhealthy or dead plants)
- Observe wetland for invasive species
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Plant success
Areas of unhealthy or
Replant areas with like
Quarterly and after
dead plants
kind while avoiding
major storm events
invasive species
Plant species
Presence of invasive
Use herbicide when
Quarterly and after
species
appropriate to remove
major storm events
invasive species
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
When the signs of unhealthy or dead plants are visible in the wetland area, replanting shall be
conducted as soon as possible to establish healthy plant population. Invasive species shall be managed
regularly.
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance, and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
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CWMTF Project No. 2019-410

Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: BMP No.10 — Within the Tidal Wetland Area from PSP to Receiving Water
Type of BMP: Tidal Creek
Summary Description of the BMP and its Components: Creek for water level rise storage and flow
BMP Footprint Area (sq. ft): 180
Has this BMP Been Constructed?: No
Projected/Actual Construction Completion Date: July 2024
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The Tidal Creek is designed to provide storage for water level rise from the adjacent waterway, and to
allow for flow from parking area stormwater runoff into the waterway.
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and
documented.
- Document all inspections
- Excessive sediment accumulation rendering visible reduction in storage volume
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Sediment accumulation
Excessive sediment
Sediment removal and
Quarterly and after
accumulation in creek
disposal offsite
major storm events
Scour
Scour visible at banks
Provide protection to
Quarterly and after
of creek
areas of scour to prevent
major storm events
future occurrences
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
When the sediment accumulation reaches a point within the creek where water is not able to flow to the
adjacent waterway, or volume of storage is reduced, maintenance shall be conducted. Scour in the
Tidal Creek shall be addressed if original path of the tidal creek is affected.
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance, and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
11 IPage
CWMTF Project No. 2019-410

Name/Number of this BMP (as identified in Exhibit A attached to this BMP O&M Plan
form):
Location: BMP No.11— At the Waterway connection to Tidal Creek at Northwest
corner of site
Type of BMP: Receiving Water
Summary Description of the BMP and its Components: Waterway connection
BMP Footprint Area: N/A
Has this BMP Been Constructed?: No
Projected/Actual Construction Completion Date: N/A
Permits that apply to this: N/A
BMP PERFORMANCE
Describe this BMP's purpose or function, its mechanisms for achieving this function, and its
intended level of performance.
The receiving water is the water downstream of the tidal creek which will be receiving water from
wetlands and stormwater runoff from the parking area
Identify what aspects of this BMP's performance will be observed or measured, how frequently, and
what records will be kept. Describe how inadequate performance will be recognized and
documented.
- Document all inspections
- Monitor the receiving water and tidal creek outlet location for signs of erosion/scour
BMP INSPECTION, MAINTENANCE, AND REPAIRS
Describe routine inspection and maintenance activities for this BMP and how frequently they
will be conducted.
Inspection
Potential Problem
Remediation
Inspection
Frequency
Trash and Debris
Debris in receiving
Remove debris and trash
Quarterly and after
water
and dispose offsite
major storm events
Erosion
Excessive Erosion at
Report to the Owner
Quarterly and after
Tidal Creek connection
major storm events
Scour
Excessive Scour at
TTidal
Report to the Owner
Quarterly and after
Creek Connection
major storm events
Describe probable non -routine maintenance activities for this BMP (conducted when/as needed):
When the receiving water shows signs of erosion from the Tidal Creek `outflow,' report any findings to
the Owner who will determine an approach to maintenance.
Identify who will be responsible for inspection, maintenance, and repairs. Describe or attach
recordkeeping form and other methods for recording inspection, maintenance, and repairs:
The USS Battleship North Carolina will routinely inspect after any major storm event or quarterly,
whichever occurs first.
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CWMTF Project No. 2019-410

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OPERATION & MAINTENANCE BMP LAYOUT
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SCALE: 1"=60'
EXHIBIT A NOT TO BE USED FOR CONSTRUCTION OR/GINgL SHEE 5/ZE ANS/ D (34'k22)
DRAWING SCALES ARE BASED ON THIS SHEET SIZE
NOTES
1. ALL NUMBERING REPRESENTS A
CORRESPONDING BMP NO. REFERENCED IN
THE OPERATION & MAINTENANCE PLAN TO BE
SUBMITTED.
LEGEND
® BMP LOCATION

Operation and Maintenance Manual
Battleship North Carolina Stormwater Wetland, Tidal Creek, and Tidal Wetland
Routine Inspections
The wetland should be inspected at least once every 3 months (quarterly) and within 24 hours following
any major storm event.
Trash/Debris
Remove any trash or debris found in or around the wetland and creek areas.
Riprap Inlet Areas
The inlet areas should be monitored for excessive sediment buildup within the riprap and adjacent
areas. If sediment is observed, we recommend evaluating the source of the sediment from the
watershed and addressing to avoid future costly sediment removal from the inlet riprap area. If
excessive sediment has accumulated, remove sediment and replace riprap per the plans. Also check the
inlet riprap for signs of rock displacement or scour. If rock is displaced, replace open area with larger
rock.
Main Stormwater Wetland Area
Each year, any unhealthy (severely distressed) or dead plants should be removed and replaced as soon
as possible. Establishing and maintaining a healthy plant population in the planting areas is
recommended. Any cattails or other invasive vegetation that take hold should be managed regularly to
avoid competition with the planted wetland vegetation and costly replanting. Algal growth covering
more than 50% of the open water surface (central channel) should also be managed. Use herbicides in
aquatic environments with caution.
Low Flow Drawdown Pipe
The Low Flow Drawdown Pipe (LFDP) should be kept free of sediment, debris, and trash. Regularly check
the LFDP for such blockages as they could affect the water drawdown time of the wetland, which could
result in damage to the wetland vegetation and costly replanting.
Maintenance Valve
Open and close the plug valve installed in the stormwater wetland riser monthly to ensure proper
function.
Riser Structure
The riser structure (including trash rack) should be kept free of sediment, debris, and trash. Check the
riser structure for leaks at the pipe connections or elsewhere. Seal leaks if found to avoid damage to the
wetland vegetation.
Principal Spillway Pipe (PSP)
The PSP should be kept free of sediment, debris, and trash. Special attention is directed to the
connection of the PSP to the Riser Structure. If cave-ins appear behind the riser structure, the owner
should contact the maintenance contractor or inspector as soon as possible as the presence of such a
condition may be indicative of some form of piping failure, which can threaten the viability of the
overlying pavement, the function of the PSP, and the overall function of the wetland system.

Stormwater Wetland Outfall Riprap Pool
Check for damage to the outlet pipe or pipe joint failure. The outfall pool area should be kept free of
excess sediment and overgrown vegetation. Monitor the outlet riprap for signs of rock displacement or
scour. Monitor the end of the rock outfall for scour and undercutting of the rock.
Flap Gate
Check the flap gate for blockages preventing proper sealing of the flap and water tightness. Check the
concrete wing wall to which the gate is mounted for cracking or damage where the gate is attached. If a
high tide or river flow event is expected, check gate beforehand to ensure proper function.
Main Tidal Wetland Area
Each year, any unhealthy (severely distressed) or dead plants should be removed and replaced as soon
as possible. Establishing and maintaining a healthy plant population in the planting areas is
recommended. Any invasive vegetation that should take hold should be managed regularly to avoid
competition with the planted wetland vegetation and costly replanting. Use herbicides in aquatic
environments with caution.
Tidal Creek
Monitor the tidal creek for excessive scour or sediment accumulation. Minor soil loss or sediment
accumulation is acceptable. Take corrective action if sediment accumulation is threatening to prevent
outflow from the stormwater wetland.
Receiving Water
Monitor the receiving water/area downstream of the tidal creek outlet for signs of erosion or other
damage.

Inspection and Maintenance Recordkeeping Form
Date of inspection/maintenance:
Who
Wetland Feature
Condition
Maintenance Work Performed?
Performed
Notes For Future Maintenance?
Maintenance?
Inlet Riprap
Areas
Main Stormwater
Wetland Area
Low Flow
Drawdown
Orifice
Maintenance
Valve
Riser Structure
Principal Spillway
Pipe
Stormwater
Wetland Outfall
Riprap Pool
Flap Gate
Main Tidal
Wetland Area
Tidal Creek
Downstream
Receiving Area