chagville eia
DESCRIPTION
Preliminary EIIA considerations for the Chagville Beach rehabilitation works in Trinidad and TobagoTRANSCRIPT
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ENVIRONMENTAL IMPACT ASSESSMENT:
CHAGVILLE, TRINIDAD &
MARINE SPATIAL ZONING
Johnson & Goberdhan November 2014
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Introduction
Location
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Introduction
The Project
Re-nourishment of Chagville Beach
Rehabilitate Beach facilities
Placement of Breakwaters and Groynes
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Introduction
Project Rationale
Chagville Beach is eroding
No natural supply of
sediments to the Beach
Requires annual
Maintenance Nourishment
Landside facilities in poor
condition
Unattractive to Tourists (L&I)
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Introduction
Project Rationale
Achieve Development Objectives
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Legislation and Regulatory Framework
National Environmental Policies
The National Environmental Policy (NEP)
The National Physical Development Plan
The National Wetlands Policy
National Biodiversity Strategy and Action Plan (NBSAP)
National Laws and Regulations
Environmental Management Act 2000
The Certificate of Environmental Clearance (CEC) Rules, 2001
The Certificate of Environmental Clearance (Designated Activities) Order, 2001
The Noise Pollution Control Rules, 2001
The Environmentally Sensitive Species (ESS) Rules, 2001
The Environmentally Sensitive Areas (ESA) Rules, 2001
Water Pollution Rules, 2001 as amended in Water Pollution (Amendment) Rules, 2006
Marine Areas (Preservation and Enhancement) Act
Occupational Safety and Health Act, 2004 and Amendment Act, 2006
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Project Description Conceptual Design
Beach
Nourishment
Install
Breakwaters
Rehabilitate
backshore
facilities
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Beach Nourishment
D50 - 0.45
Berm width -9m
Berm Elev 1.3m
Entire beach approx. 760m long
Volume: 23,700m3
Source: Guyana quartz sand
-3
-2.5
-2
-1.5
-1
-0.5
0
0.5
1
1.5
2
0 20 40 60 80 100
Ele
vation (
m)
Distance Offshore (m)
Existing profile
Design profile
Project Description Conceptual Design
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Breakwaters and
Groynes
BW are on
average 80 90m
offshore
Crest Elevation at
0.0m
Placed in 4m water
Depth on overage
Crest set to msl
Boulders sized to resist
waves from cat 2 Hurricane
Project Description Conceptual Design
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Breakwaters and
Groynes
Structure Length (m) Volume (m) BW1 125 5500
BW2 133 5852
BW3 100 4400
BW4 100 4400
BW5 122 5368
G1 41 902
G2 74 1628
Total 695 28050
Project Description Conceptual Design
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Rehabilitate Beach facilities
Washrooms/Areas
Lifeguard House
Restaurants
Solid waste Disposal
Wastewater Disposal system
Storm Drains
Project Description Conceptual Design
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Construction Method Nourishment
Deep draft/Large Capacity Barge from Guyana with
clamshell offloading to small barge
Small Barge and long reach excavator and small
draft (0.9m)
Bulldozer onshore
Project Description Construction
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Construction Method Breakwaters and Groynes
Remove biophysical features in footprint of structures
Placement of turbidity barriers
Deliver boulders to site via barge from stockpile area
Place boulders on sea floor and build up to crest
Project Description Construction
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Construction Method Breakwaters and groynes
Trucks along highway during off peak hours to wharf
Barge from Wharf to Site
Project Description Construction
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Construction Phasing
Phase 1
Rehabilitation works (buildings, drainage, sewerage,
landscaping)
Placement of Groynes and Western Breakwaters
Phase 2
Nourishment of entire beach
Placement of Eastern Breakwaters
Project Description Construction
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Environmental Monitoring (Construction)
Water Quality
Dust
Noise
Long term monitoring (Post Construction)
Currents
Shoreline location
Water Quality
Project Description Monitoring
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Description of the Environment
Physical
Biological
Social
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Description of the Environment
Physical
Topography
Steep hills
to the north
Site is
gently
sloping to
south
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Description of the Environment
Physical
Hydrology
Rivers on
either
boundaries
Site drains
to sea
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Description of the Environment
Physical
Bathymetry
Slopes 3%
out to 100m
offshore
Rapid fall
off after -
4m
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Description of the Environment
Physical
Sediments
DESCRIPTION SAMPLE
LOCATION
MEAN MEDIAN CLASSIFICATION
(FOLK & WARD) mm mm
West
Upper Beach 0.31 0.31 Slightly Gravelly SAND
Mid Beach 1.16 0.86 Sandy GRAVEL
Lower Beach 0.25 0.26 Slightly Gravelly SAND
Central
Upper Beach 0.22 0.22 Slightly Gravelly SAND
Mid Beach 0.61 0.40 Slightly Gravelly SAND
Lower Beach 0.15 0.15 Gravelly SAND
East
Upper Beach 0.39 0.39 Slightly Gravelly SAND
Mid Beach 0.73 0.71 Slightly Gravelly SAND
Lower Beach 0.67 0.53 Gravelly SAND
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Description of the Environment
Physical
Wind Waves and Currents
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Description of the Environment
Physical
Wind Waves and Currents
Location
Range
Hs (m) Tp (s) Dp ()
West 0.1 - 0.3 3.0 - 7.3 140 - 160
Central 0.01 - 0.2 2.5 - 5.7 140 - 165
East - - -
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Description of the Environment
Physical
Wind Waves and Currents
Circulation in gulf of Paria
due to Guina current
Carenage bay circulation is
characterized by slow
currents (15cm/s)
with westerly currents during
falling tides and easterly
currents during rising tides.
Alongshore currents due to
waves easterly 0.1cm/min
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Description of the Environment
Physical
Shoreline Morphology
Shoreline use changed from swamp to beach
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Description of the Environment
Physical
Shoreline
Morphology
Shoreline use
changed from
swamp to beach
Shoreline is
developed
Shoreline is
receding at
approximately
0.3m per year
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Description of the Environment
Physical
Shoreline
Morphology
Shoreline use
changed from
swamp to beach
Shoreline is
developed
Shoreline is
receding at
approximately
0.3m per year
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-2
-1
0
1
2
3
0 20 40 60 80 100 120
Elev
atio
n (
m)
Distance (m)
20000120 20000822 20070518 20070926
20090421 20090727 20100121 20100729
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Description of the Environment
Biological
Sea grass
Fish
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Impact Matrix - Physical
During Construction Post Construction Positive Negative Short-term Long-term Low Moderate High Low Moderate High
Increased Noise Pollution (Use of Heavy
Machinery)x x x x x
Increased Air Pollution (Dust and Fumes) x x x x xIncreased Water Pollution (Oils,
Gasoline, Solid Waste etc)x x x x x
Spillage of Boulders and other materials x x x x xIncreased Sedimentation of the Marine
Environmentx x x x x
Increased Soild Waste Generated x x x x x xIncreased Traffic (Marine/Road) x x x x x xIncreased Wear and Tear of the Road x x x x x xReduced Wave Energy x x x x xReduced Current Speeds x x x x xReduced Beach Erosion x x x x xReduced Flushing Time x x x x xIncreased Beach Berm x x x x xVisual Asthetics x x x x x
Potential Impact
Physical
DurationNatureTiming Magnitude Significance
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Impact Matrix Biological
During Construction Post Construction Positive Negative Short-term Long-term Low Moderate High Low Moderate High
Compression of Beach Sediment
(Burrowing Fauna)x x x x x
Introduction of Benthic Ecology x x x x xSedimentation (Wetlands, Seagrass and
other marine life)x x x x x
Release of Toxins from Sediment
(Wetlands, Seagrass and other marine
life)
x x x x x
Decreased Water Quality (Wetlands,
Seagrass and other marine life)x x x x x
Fish or Invertebrate Displacement x x x x xHabitat Fragmentation x x x x x
Biological
Potential ImpactTiming Nature Duration Magnitude Significance
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Impact Matrix - Social
During Construction Post Construction Positive Negative Short-term Long-term Low Moderate High Low Moderate High
Increased Employment Opportunities x x x x xTraffic Congestion x x x x x xNo Use of Beach (Recreational Users,
Spritual Baptist, Lifeguards)x x x x x
Heavier Beach Use x x x x xIncreased Tourism x x x x xIncreased Recreation Activities
(Swimming, Watersports etc)x x x x x
Increased Recreational Safety (Reduced
Wave Energy for Swimming and other
Watersports)
x x x x x
Increased Bussiness (Retail) x x x x xIncreased Financial Cost to Users (Paying
to Use Facilities)x x x x x
Increased Security for Users x x x x xVisual Asethics x x x x x x
Timing Nature Duration Magnitude Significance
Social
Potential Impact
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Mitigation Measures
Monitoring of decibel levels
Construction will stop before nightfall
Appropriate PPE for all persons on site
Air Quality Monitoring. If threshold exceeded, work will be stopped.
Occasssional 'wetting'
Water Quality Monitoring
Proper inspection and maintenance of all vessels
Proper storage of solid waste until disposal
Spill Plan : Alert CDA. Personel trained to respond approriately
Trained personel
Spill cleanup
Water Quality Monitoring
Wash Boulders at Source
Sediment traps/silt screens
Adequate bathroom and garbage facilites
Proper storage of solid waste until disposal
Reduce Road Traffic - Use of barge
Avoid peak traffic times
Increased Wear and Tear of the Road Use of barge instead of trucks
Opening in Breakwaters
Aim to improve water quality - flushing becomes less crucial
Increased Noise Pollution (Use of Heavy
Machinery)
Increased Air Pollution (Dust and Fumes)
Increased Water Pollution (Oils,
Gasoline, Solid Waste etc)
Spillage of Boulders and other materials
Increased Sedimentation of the Marine
Environment
Increased Soild Waste Generated
Increased Traffic (Marine/Road)
Reduced Flushing Time
Mitigation Measures
Physical
Potential Impact of Negative
Nature
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Mitigation Measures
Compression of Beach Sediment
(Burrowing Fauna) Reduce useage of heavy equipment
Water Quality Monitoring
Wash Boulders at Source
Sediment traps/silt screens
Water Quality Monitoring
Stop work and initiate cleanup if toxicity is too high
Water Quality Monitoring
Proper inspection and maintenance of all vessels
Proper storage of solid waste until disposal
Spill Plan : Alert CDA. Personel trained to respond approriately
Fish or Invertebrate Displacement No Mitigation
Habitat Fragmentation No Mitigation
Loss of Habitat in footprint of Structures No Mitigation
Loss of Flora in footprint of Structures No mapped flora - possibly no impact
Sedimentation (Wetlands, Seagrass and
other marine life)
Mitigation Measures
Biological
Release of Toxins from Sediment
(Wetlands, Seagrass and other marine
life)
Decreased Water Quality (Wetlands,
Seagrass and other marine life)
Potential Impact of Negative
Nature
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Mitigation Measures
Reduce Road Traffic - Use of barge
Avoid peak traffic times
Avoid peak times (Mar, Jul, Aug, Dec)
Phased Construction - Minimal Closure Time
Increased Financial Cost to Users (Paying
to Use Facilities) No Mitigation - Necessary for upkeep
Visual Asethics Breakwater height at MSL - minimal disruption of view
Traffic Congestion
No Use of Beach (Recreational Users,
Spritual Baptist, Lifeguards)
Social
Mitigation MeasuresPotential Impact of Negative
Nature
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Alternatives
No Action
No cost involved
Beach does not meet its full potential
Continued degradation
Unsafe beach
Alternative Site for Development
Encourages development at other locations
May not be feasible at other locations
More time involved Assessment of alternative sites
More cost involved
Protect Existing Beach
Less cost involved than Nourishment
Only some portions of the beach are currently useable
Narrow beach with unsightly structures
No improvement to visitors
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Monitoring and Management
5 year Monitoring and Management Plan
Waves and Currents
Beach Profiles
Integrity of Structures
Water Quality
Sediment Quality
Benthic Ecology
Mangrove Survey
Sea grass Survey
Recommendations would then be given to determine if Monitoring and Management Plan should continue
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GIS
Beach Profiles
Rivers
Roads
Coastline
Bathymetry
Existing Seawall
Study Area
Wetland
Trees
Buildings
Car Park
Proposed Groynes
Proposed Breakwaters
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Public Consultations
Questionnaire
Description of Interviewee
Housing, Health and Social Services
Specific Issues Regarding the Project
Employment and Income
Education
Range of persons interviewed
Lifeguards
CDA employee
Vendor
Recreational Users
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Public Consultations - Findings
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Public Consultations - Findings
Major Concerns about Chagville
Crime
Pollution
No sandy beach
Drainage
Suggested Improvements
Beach Facilities
More Lifeguard Presence
Regular Clean-ups
No Smoking Zone
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Zoning
Coastal Zoning?
Coastal management tool
Based on a concept of separating and controlling
incompatible uses
Can be modified to suit varying social economic and
political environments
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Zoning
Development Plan and CDA objectives
Recreation (insert image)
Ecotourism (website)
Conservation (website)
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Zoning
Mechanics of Zoning
Allowed, allowed with permission
Prohibited, allowed with permission
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Zoning
Plan
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Zoning
Plan
Area Category Activities Allowed Notes
1 Preservation
area Snorkelling with permit Area has seagrass beds which are
to be protected
2 Water Sports non motorized sports, canoeing,
floating provides a buffer for protected
areas
3 Channel Motorized sports with permit,
yachts, cargo vessels provides access to existing
boating facilities
4 Water sports motorized sports with permit;
motorized sports without permit
5 Preservation
area Snorkelling with permit
Outfall for river, has degris from
time to time that needs to be
remived, sediment bars are also
present which can increase
turbidity if disturbed
6
Recreational
Bathing/Swim
ming Snorkelling, swimming, floating shallow beach are suitable for
recreational swimming