HomeMy WebLinkAbout2023-10-31_Avila PH2-3 Stormwater O&M_CFDSTORMWATER CONTROL MEASURES
OPERATION AND MAINTENANCE PLAN
For
TRACT 3089 - AVILA RANCH
PHASES 2 & 3
Entities Responsible for Maintenance:
Community Facilities District (CFD), City of San Luis Obispo
July 2023
Prepared by:
612 Clarion Court
San Luis Obispo, CA 93401
805 544-4011
Job Number: 1493-0007 Date Signed: 7/28/2023
PUBLIC STORMWATER OPERATIONS
AND MAINTENANCE MANUAL
FILE COPY
STORM-0575-2023
Operations and Maintenance Plan for Tract 3089 Avila Ranch (Ph 2-3) - CFD
July 2023
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Table of Contents
Introduction.................................................................................................................... 3
General Information ...................................................................................................... 4
Facilities to be Maintained ............................................................................................ 4
Bioswale With Underground Gravel Trench ............................................................. 5
Underground Gravel Chambers - Parks ................................................................... 7
Vegetated Basin ...................................................................................................... 8
Vegetated Swale (Bypass Channel) ........................................................................ 9
Site Inspection Procedures ........................................................................................ 10
Reporting Requirements ............................................................................................ 10
Revisions of Pollution Mitigation Measures ............................................................. 10
Tables
Table 1. Stormwater Control Measures ........................................................................... 4
Table 2. Bioswale with Underground Gravel Trench ....................................................... 6
Table 3. Park Gravel Chamber ........................................................................................ 7
Table 4. Vegetated Basin ................................................................................................ 8
Table 5. Vegetated Swale (Bypass Channel) .................................................................. 9
Figures
Figure 1. Tract 3089 – Avila Ranch Development ........................................................... 3
Figure 2. Bioswale Typical Section .................................................................................. 5
Figure 3. Park Gravel Chamber Typical Section ............................................................. 7
Appendix
Avila Ranch (Phases 2-3) Stormwater Control Measures (SCM) Exhibit
Maintenance & Inspection Forms
Operations and Maintenance Plan for Tract 3089 Avila Ranch (Ph 2-3) - CFD
July 2023
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Introduction
This document is an operations and maintenance plan for the long-term inspection,
maintenance, and cleaning requirements of the Stormwater Control Measures
(SCMs) installed for Phases 2 & 3 of the Avila Ranch project. The project is a part of
the greater Avila Ranch Phases 1-6, which includes 149 acres of proposed
development including single and multi-family homes, commercial areas, parks, and
agricultural open space.
Below is a list of associated documents related to this report, for reference:
· Avila Ranch Development – Phase 1 Drainage Report prepared by RRM,
dated 9/17/2018
· Stormwater Control Plan for Avila Ranch, prepared by RMM, dated 3/22/2022.
· Annual Stormwater Maintenance Plan – Avila Ranch, prepared by RRM.
· Tract 3089 Avila Ranch – Phases 2, 3, 4, 5 & 6 Mass Grading – Drainage Report
(Vol. 1 of 2), prepared by Wallace Group, dated April 2023.
· Tract 3089 Avila Ranch – Phases 2, 3, 4, 5 & 6 Final Improvements – Drainage
Report (Vol. 2 of 2), prepared by Wallace Group, dated April 2023.
· Tract 3089 Avila Ranch – Phases 2, 3, 4, 5 & 6 Stormwater Control Plan, prepared by
Wallace Group, dated December 21, 2022.
· Tract 3089 – Public Improvement Plans – Phases 2 & 3, prepared by Wallace Group.
Figure 1. Tract 3089 – Avila Ranch Development
Phases 2 & 3
Phase 4, 5 & 6
Phase 1
Buckley Road
Va
c
h
e
l
l
L
a
n
e
Venture Drive
Earthwood Lane
Operations and Maintenance Plan for Tract 3089 Avila Ranch (Ph 2-3) - CFD
July 2023
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General Information
The stormwater control measures (SCMs) proposed across Phases 2-3 of Avila
Ranch have been designed to capture, treat, and retain stormwater where feasible.
High groundwater levels and poor soil infiltration capabilities were identified in Phases
2 and 3, which limited greater utilization of retention and infiltration facilities. For more
information on project site conditions and SCM design, refer to the Phases 2-6
Drainage Report and Stormwater Control Plan, prepared by Wallace Group.
SCMs proposed for this project include the use of bioswales with underground gravel
trenches, underground gravel chamber systems, a vegetated basin, vegetated
swales, and concrete-lined drainage channels.
Routine inspection, maintenance, and repair is crucial to the long-term success and
performance of these stormwater facilities. The proper operation and maintenance of
these facilities is described in the following sections.
Facilities to be Maintained
Table 1 provides a summary of each type of stormwater control measure. Refer to the
exhibits in the appendix for a map of where each SCM is located.
Table 1. Stormwater Control Measures
SCM ID * SCM Type Maintenance Entity
· B(#5), B(#6)
· C(#3), C(#4), C(#5)
· D(#1), D(#2), D(#3), D(#4),
D(#5), D(#6), D(#7), D(#8)
Roadside bioswale with
underground gravel
trench
Community Facilities District
(CFD) – Public Street/ ROW
· B(#9)
Park
Underground gravel
chamber system
Community Facilities District
(CFD) – Public Park
· Basin B - B(#10) Vegetated basin Community Facilities District
(CFD) – Public Park
· Bypass Channel Vegetated swale Community Facilities District
(CFD) – Open Space
* Referenced from Avila Ranch Phases 2-6 Stormwater Control Plan, see Stormwater Control
Measure (SCM) Exhibit
Operations and Maintenance Plan for Tract 3089 Avila Ranch (Ph 2-3) - CFD
July 2023
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Bioswale With Underground Gravel Trench
The bioswales proposed for Phases 2 & 3 include roadside bioswales. The proposed
bioswales will be layered with 24” of biofiltration soil media (BMS) with Class III
permeable aggregate base underneath to treat stormwater and promote infiltration.
The infiltration rate of the existing soils for these bioswale areas have been tested and
found suitable for stormwater infiltration and groundwater recharge. The bioswale
section includes specific materials and depths as shown in the following summary:
· Top layer of planted landscape
· Second layer of bioretention soil media (24” thick)
· Third layer of No. 4 open graded aggregate
· Fourth layer of Class III aggregate
During larger storm events, the roadside bioswales will overflow into the street and
continue downstream to other SCMs or be collected in the proposed storm drain
system which convey flows to Tank Farm Creek. All proposed bioswales must be
maintained and kept clean to function effectively, especially during the rainy season.
Refer to Figure 1 below for a typical bioswale section.
Figure 2. Bioswale Typical Section
Operations and Maintenance Plan for Tract 3089 Avila Ranch (Ph 2-3) - CFD
July 2023
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The following maintenance matrix is provided for bioswales. A corresponding
maintenance checklist is provided in the appendix for proper record keeping of these
maintenance activities.
Table 2. Bioswale with Underground Gravel Trench
Component Description Frequency Maintenance Activities
Planting Location specific native plant species
that are selected for their resistance to
inundation and drought conditions and
provide evapotranspiration and pollutant
uptake to improve the quality and reduce
the quantity of stormwater discharged to
nearby receiving waters.
Semiannually,
before & after
storm event
Irrigate, trim, prune, replace
dead plants, and replant when
necessary. Remove invasive
plants and check for appropriate
levels of irrigation.
Ground Cover A layer of organic or inorganic materials
applied to the surface of a bioswale area
to maintain soil moisture, reduce weed
growth and reduce soil compaction.
Organic mulches can remove pollutants
and add nutrients to the soil as the mulch
decomposes.
Beginning and
end of wet
season, as
needed
Spot mulch, re-mulch or replace
ground cover.
Soil media An engineered soil material designed to
provide a long-term permeability rate
capable of infiltrating 5" of runoff per
hour and maintain sufficient moisture
content to promote healthy plant growth.
This media consists of approximately 60-
70% sand and 30-40% compost.
Semiannually,
before & after
storm event
Inspect for uniform distribution
throughout SCM and percolation
capability. Inspect for
accumulated debris/sediment
and signs of channelization.
Shallow aeration and tilling,
deep aeration, excavate and
replace media.
Inlets/Outlets Curb cuts delivering concentrated flows
to the SCM or allowing runoff to flow out
of the SCM. Storm drain inlets allowing
excess runoff to flow out of SCM.
Semiannually,
before & after
storm event
Clean debris & sediment from
structure/outlet, repair chips &
cracks, excavate and replace
structure if needed. Inspect for
signs of plugging and erosion.
Splash pad/
Rock slope
protection
(RSP)
These structures prevent erosion to the
soil at the point where water enters the
BMP and help to distribute concentrated
flows. These structures are located
directly adjacent to the inlet point-
whether a curb cut or an inlet location.
Semiannually,
before & after
storm event
Clear obstructing debris &
sediment, replace missing or
eroded rip rap as needed.
Embankments Vegetated side slopes of the SCMs. Beginning and
end of wet
season, as
needed
Check for signs of erosion or
instability. Remove any
obstructions or rehabilitate
drainage slopes as needed.
** Note: If the performance of an SCM is severely limited or if failure of the SCM is suspected, the underground
aggregate rock storage layer may need to be investigated. If underground aggregate layer is found to be
clogged or failing, it may need to be excavated, removed, and replaced.
Operations and Maintenance Plan for Tract 3089 Avila Ranch (Ph 2-3) - CFD
July 2023
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Underground Gravel Chambers - Parks
Subsurface gravel chambers will be implemented to retain the 95th percentile runoff in
park areas, specifically Park E in Phase 3. The gravel chambers will incorporate
Class III aggregate base at varying widths and depths to store runoff and promote
infiltration.
Runoff from the park will flow to sump locations within landscaped and turf areas to
be collected by a storm drain inlet, which will direct runoff through a 4” PVC pipe to
the subsurface gravel chamber. The storm drain inlets will be positioned 6” above the
sump elevations to provide additional retention and infiltration before filling up the
underground gravel chamber. In larger storm events, excess stormwater will pond
within the sump areas until it safely overtops and escapes into the primary storm drain
network. Refer to Figure 4 for a typical detail of the proposed park gravel chambers.
Figure 3. Park Gravel Chamber Typical Section
The following maintenance matrix is provided for the underground gravel chamber
systems. A corresponding maintenance checklist is provided in the appendix for
proper record keeping of these maintenance activities.
Table 3. Park Gravel Chamber
Component Description Frequency Maintenance Activities
Inlet/Outlets Storm drain box and grate with 4”
PVC pipe to gravel trench. Storm
drain inlet is integrated with storm
drain system to convey excess flows.
Semiannually,
before & after
storm event
Lift grate cover to clean. Vacuum any
sediment accumulated at the bottom
of the box and remove any trash or
debris. Inspect for signs of plugging
and erosion, as needed. Repair any
chips & cracks. Excavate and replace
structure, per plan, if needed.
** Note: If the performance of an SCM is severely limited or if failure of the SCM is suspected, the underground
aggregate rock storage layer may need to be investigated. If underground aggregate layer is found to be
clogged or failing, it may need to be excavated, removed, and replaced.
Operations and Maintenance Plan for Tract 3089 Avila Ranch (Ph 2-3) - CFD
July 2023
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Vegetated Basin
One vegetated shallow retention basin has been integrated into the proposed Phase
3 park to retain stormwater and direct it into the underground chamber system,
discussed above. This vegetated basin is in the turf sump area within the park. The
basin is designed to maintain a maximum of 6” of ponding. Larger storm events will
overtop and safely escape into nearby primary storm drain inlets.
Refer to Table 4, below, for the combined vegetated basins and vegetated swales
maintenance matrix.
Table 4. Vegetated Basin
Component Description Frequency Maintenance Activities
Inlet/Outlets Storm drain inlets delivering concentrated
flows to the SCM. Rock slope protection
allowing excess runoff to flow out of SCM.
Semiannually,
before & after
storm event
Inspect for signs of plugging
and erosion. Clean debris &
sediment from inlet pipes.
Embankment Vegetated side slopes of the SCMs. Beginning and
end of wet
season, as
needed
Check for signs of erosion or
instability. Remove any
obstructions or rehabilitate
drainage slopes as needed.
Planting Location specific native plant species that
are selected for their resistance to
inundation and drought conditions and
provide evapotranspiration and pollutant
uptake to improve the quality and reduce
the quantity of stormwater discharged to
nearby receiving waters.
Semiannually,
before & after
storm event
Cut or pull weeds from basin
or surrounding landscape
and remove to avoid
accumulation. Replace
managed turf, where
necessary
Splash pad/
Rock slope
protection
(RSP)
These structures prevent erosion to the soil
at the point where water enters the BMP
and help to distribute concentrated flows.
Semiannually,
before & after
storm event
Clear obstructing debris &
sediment, replace missing or
eroded rip rap as needed.
Basin Vegetated basin bottom and side slopes. Semiannually,
before & after
storm event
Inspect for signs of erosion,
siltation, or excess sediment
build-up. Remove debris and
trash as needed. If erosion,
siltation, or excess sediment
is observed, re-grade and
re-plant basin according to
design plans.
Operations and Maintenance Plan for Tract 3089 Avila Ranch (Ph 2-3) - CFD
July 2023
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Vegetated Swale (Bypass Channel)
The proposed bypass channel adjacent to Tank Farm Creek has been designed as a
large, vegeated swale to provide water quality treatment from tributary runoff of the
project. This onsite vegeated bypass channel will also receive and treat offsite
stormwater run-on from the northern proerties adjacent to Avila Ranch. The bypass
channel is a wide, flat-bottomed channel with minimal longitudinal slope. It will be
vegetated with grasses and native plants to allow for sufficient hydraulic residence
times for polutant filtration, lower flow velocities aiding in erosion control, and
infiltration of stormwater.
The following maintenance matrix is provided for the vegetated bypass channel. A
corresponding maintenance checklist is provided in the appendix for proper record
keeping of these maintenance activities.
Table 5. Vegetated Swale (Bypass Channel)
Component Description Frequency Maintenance Activities
Inlet/Outlets Storm drain outlets deliver concentrated
flows to the bypass channel. Rock slope
protection allowing excess runoff to flow out
of the channel into Tank Farm Creek.
Semiannually,
before & after
storm event
Inspect for signs of plugging
and erosion. Clean debris &
sediment from outlet pipes.
Embankment Vegetated side slopes of the SCMs. Beginning and
end of wet
season, as
needed
Check for signs of erosion or
instability. Remove any
obstructions or rehabilitate
drainage slopes as needed.
Planting Location specific native plant species that
are selected for their resistance to
inundation and drought conditions and
provide evapotranspiration and pollutant
uptake to improve the quality and reduce
the quantity of stormwater discharged to
nearby receiving waters.
Semiannually,
before & after
storm event
Cut or pull weeds from swale
or surrounding landscape
and remove to avoid
accumulation.
Splash pad/
Rock slope
protection
(RSP)
These structures prevent erosion to the soil
at the point where water enters the BMP
and help to distribute concentrated flows.
Semiannually,
before & after
storm event
Clear obstructing debris &
sediment, replace missing or
eroded rip rap
** Note: Bypass Channel is located within environmental permitting agency jurisdiction and additional permits
may be required for maintenance operations.
Operations and Maintenance Plan for Tract 3089 Avila Ranch (Ph 2-3) - CFD
July 2023
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Site Inspection Procedures
All site inspections should follow each inspection item outlined in the matrix tables
and inspection templates. Additional comments and photos should also be included
on the checklist form as needed.
Records regarding inspections and maintenance activities as outlined in this plan are
to be retained by the owner for a minimum of at least five years, and copies shall be
made available upon request to the City of San Luis Obispo or Regional Water
Quality Control Board. These records may include copies of completed inspection
reports and maintenance checklists to document any inspection and maintenance
activities that were conducted over the preceding five years. Corrective actions,
repairs, or replacements should also be documented and maintained with SCM
inspection and maintenance records for a minimum of five years.
The maintenance checklists to be used during inspections can be found in the
appendix.
Reporting Requirements
All required annual inspections, maintenance activities, forms and corresponding
documentation must be submitted to the City of San Luis Obispo no later than June
15th of each year.
Revisions of Pollution Mitigation Measures
If future correction or modification of stormwater control measures or procedures is
required, the Owner shall obtain approval from the governing stormwater agency prior
to commencing any work. Corrective measures or modifications shall not cause
discharges to bypass or otherwise impede existing stormwater control measures.
Operations and Maintenance Plan for Tract 3089 Avila Ranch (Ph 2-3) - CFD
July 2023
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Appendix
Avila Ranch (Phases 2-3) Stormwater Control Measures (SCM) Exhibit
Maintenance & Inspection Forms:
· Bioswale With Underground Gravel Trench
· Underground Gravel Chamber
· Vegetated Basin
· Vegetated Swale (Bypass Channel)
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H (#13)H (#14)H (#15)
H (#16)
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H (#19)
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E-PH4b (#6)
E-PH4b (#5)
E-PH4a (#1)
E-PH4a (#2)
E-PH4a (#3)
E-PH4a (#4)
E (#2)
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D (#7)
D (#8)
G (#1)
G (#2)
G (#3)
G (#4)
B (#11)
COLLECTED BY FUTURE
ONSITE DRAINAGE SYSTEM
WHICH WILL BE CONNECTED
TO PH. 2-6 SD NETWORK
DMA E-PH4a & E-PH4b
STORMWATER TO BE
COLLECTED BY FUTURE
ONSITE DRAINAGE SYSTEM
WHICH WILL BE CONNECTED
TO PH. 2-6 SD NETWORK
H (#20)
COMM #2
5-89 5-80 5-67
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5-655-825-87
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5-635-845-85
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1 IN = 60 FT
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VENTURE DRIVE
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PAGE 1 OF 4
BASIN B
BOT. ELEV ≈ 113.50
GW ELEV = 105.00
Avila Ranch - Phases 2-6
Stormwater Control Measures (SCM) Exhibit
WRIGHT BROTHERS
BASIN H-1
POND = 0.6' + 1.0' FB
BOT. ELEV = 112.00
GW ELEV = 105.00
BASIN H-2
POND = 0.6' + 1.0' FB
BOT. ELEV = 110.00
GW ELEV = 105.00
DRAWN BY: RAH/ ZKP
5-16-2022
1493-0007
PROPOSED CONCRETE-LINED
PERIMETER SWALE (SEE AVILA RANCH
PHASES 2-6 MASS GRADING PLAN).
PROPOSED
CONCRETE-LINED
PERIMETER SWALE (SEE
AVILA RANCH PHASES 2-6
MASS GRADING PLAN).
PROPOSED CONCRETE-LINED
PERIMETER SWALE (SEE AVILA RANCH
PHASES 2-6 MASS GRADING PLAN).
PROPOSED CONCRETE-LINED
PERIMETER SWALE (SEE AVILA RANCH
PHASES 2-6 MASS GRADING PLAN).
LEGEND:
PHASE BOUNDARY
DRAINAGE MANAGEMENT AREA BOUNDARY
BIOSWALE WITH UNDERGROUND GRAVEL TRENCH
MOTORCOURT/ ALLEY GRAVEL CHAMBER
OFFSET GRAVEL CHAMBER
VEGETATED RETENTION BASIN
RETENTION-BASED TREATMENT AREA (REFER
TO APPENDIX F, ATTACHMENT E COMPLIANCE)
PERMEABLE PAVERS WITH GRAVEL CHAMBER
PROPOSED STORM DRAIN NETWORK
SCM IDENTIFICATION (REFER TO PHASES 2-6
SCM SIZING CALCULATIONS).
PHASE 5 LOT NUMBERS
PHASE 2, 3, 4, 6 LOT NUMBERS
SD
A (#1)
0-00
199
MULTI-FAMILY LOTS
NOT INCLUDED
MULTI-FAMILY LOTS
NOT INCLUDED
MULTI-FAMILY LOTS
NOT INCLUDED
RAC H E L A . H AWTH
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C I V I L
No. 73686
A L
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REGISTE R E D P R O F E SSIONAL E
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12/21/20225/19/2023
NORTH BOUNDARY
BYPASS CULVERTS
Yes No REQUIRED ACTION ACTION TAKEN
If yes, irrigate, trim, prune, replace
dead plants, and replant when
necessary. Remove invasive plants
and check for appropriate levels of
irrigation.
If no, spot mulch or re-mulch/ replace
ground cover
If yes, inspect for accumulated
debris/sediment and signs of
channelization. Shallow aeration and
tilling, deep aeration, excavate and
replace media.
If yes, remove & replace clogged
surface, or excavate & replace entire
layer
If no, clean debris & sediment from
structure/outlet, repair chips & cracks,
excavate and replace structure if
needed.
If yes, clear obstructing debris &
sediment, replace missing or eroded
rip rap
If yes, remove any obstructions or
rehabilitate the drainage slopes as
needed.
SITE PHOTOS ATTACHED
5) Inspect the bioswale inlet and outlet
structures for signs of plugging or
damage. Are the structures in
adequate condition and are they able
to carry out designed functions?
2) Inspect the organic materials at the
surface of the bioswale. Is the mulch
coverage/ ground cover even and
consistent throughout the surface?
3) Inspect the bioswale for uniform
distribution and percolation
capabilities of the bioretention soil
media. Are there signs of exposed,
uneven, or eroded bioretention soil
media?
4) Inspect the bioswale for ponding
water. Is there standing water that may
indicated poor drainage within the
bioswale?
6) Inspect the splash pads/ rock slope
preotection within the bioswale. Is
there any indication the rip rap has
been displaced or any other signs of
erosion?
7) Inspect the vegetated side slopes of
the bioswales. Are there signs of
erosion or instability?
** Note: If the performance of an SCM is severely limited or if failure of the SCM is suspected, the underground aggregate
rock storage layer may need to be investigated. If underground aggregate layer is found to be clogged or failing, it may
need to be excavated, removed, and replaced.
MAINTENANCE ITEMS
1) Inspect the bioswale vegetation
condition. Are there signs of
overgrowth, dead plants, or invasive
weeds?
WEATHER CONDITIONS:
NAME OF INSPECTOR:
DATE AND TIME OF INSPECTION:
SCM NUMBER:
RAINFALL IN LAST 24 HOURS (inches):
MAINTENANCE RECORD
AVILA RANCH - SAN LUIS OBISPO - CA
BIOSWALE WITH UNDERGROUND GRAVEL TRENCH
SCM LOCATION:
Yes No REQUIRED ACTION ACTION TAKEN
If no, lift grate cover to clean. Vacuum
any sediment accumulated at the
bottom of the box and remove any
trash or debris. Inspect for signs of
plugging and erosion, as needed.
Repair any chips & cracks. Excavate
and replace structure, per plan, if
needed.
NAME OF INSPECTOR:
MAINTENANCE ITEMS
1) Inspect the inlet structures for signs
of plugging or accumulated debris. Is
the structure in adequate condition
and is able to carry out its function?
** Note: If the performance of an SCM is severely limited or if failure of the SCM is suspected, the underground aggregate
rock storage layer may need to be investigated. If underground aggregate layer is found to be clogged or failing, it may
need to be excavated, removed, and replaced.
SITE PHOTOS ATTACHED
DATE AND TIME OF INSPECTION:
RAINFALL IN LAST 24 HOURS (inches):
WEATHER CONDITIONS:
MAINTENANCE RECORD
AVILA RANCH - SAN LUIS OBISPO - CA
PARK UNDERGROUND GRAVEL CHAMBER
SCM NUMBER:
SCM LOCATION:
Yes No REQUIRED ACTION ACTION TAKEN
If yes, clean debris and sediment from
inlet pipe.
If yes, remove any obstructions or
rehabilitate drainage slopes as
needed.
If yes, cut or pull weeds from basin or
surrounding landscape. Remove to
avoid accumulation. Replace
managed turf where necessary
If yes, clear obstructing debris &
sediment, replace missing or eroded
rip rap
If yes, remove debris and trash as
needed. If erosion, siltation, or excess
sediment is observed, re-grade and re-
plant basin according to design plans.
DATE AND TIME OF INSPECTION:
MAINTENANCE RECORD
AVILA RANCH - SAN LUIS OBISPO - CA
VEGETATED BASIN
SCM NUMBER:
SCM LOCATION:
SITE PHOTOS ATTACHED
2) Inspect the side slope conditions of
the basin. Are there signs of erosion or
slope instability?
3) Inspect the basin vegetation
condition. Are there signs of
overgrowth, dead plants, or invasive
weeds?
RAINFALL IN LAST 24 HOURS (inches):
WEATHER CONDITIONS:
NAME OF INSPECTOR:
MAINTENANCE ITEMS
1) Inspect the inlet structures for signs
of plugging or accumulated debris.
Are the inlet pipes clogged?
4) Inspect overall basin condition. Is
there any indication erosion, siltation,
or excess sedimentation?
4) Inspect the splash pads within the
basin. Is there any indication the rip
rap has been displaced or any other
signs of erosion?
Yes No REQUIRED ACTION ACTION TAKEN
If yes, clean debris and sediment from
inlet pipe.
If yes, remove any obstructions or
rehabilitate drainage slopes as
needed.
If yes, cut or pull weeds from swale or
surrounding landscape. Remove to
avoid accumulation.
If yes, clear obstructing debris &
sediment, replace missing or eroded
rip rap
DATE AND TIME OF INSPECTION:
** Note: Bypass Channel is located within environmental permitting agency jurisdiction and additional permits may be
required for maintenance operations.
MAINTENANCE RECORD
AVILA RANCH - SAN LUIS OBISPO - CA
VEGETATED SWALE (BYPASS CHANNEL)
SCM NUMBER:
RAINFALL IN LAST 24 HOURS (inches):
WEATHER CONDITIONS:
4) Inspect the splash pads and rock
slope protection within the swale. Is
there any indication the rip rap has
been displaced or any other signs of
erosion?
SCM LOCATION:
SITE PHOTOS ATTACHED
NAME OF INSPECTOR:
MAINTENANCE ITEMS
1) Inspect the inlet structures for signs
of plugging or accumulated debris.
Are the inlet pipes clogged?
2) Inspect the side slope conditions of
the swale. Are there signs of erosion or
slope instability?
3) Inspect the swale or basin
vegetation condition. Are there signs of
overgrowth, dead plants, or invasive
weeds?