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NRCA GUIDELINES
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for the
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CONSTRUCTION,
MAINTENANCE
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and
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MONITORING
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of
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UNDERWATER PIPELINES
& CABLES
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in the
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COASTAL ZONE
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prepared for
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NATURAL RESOURCES CONSERVATION AUTHORITY
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by Cowell L. Lyn |
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1. INTRODUCTION
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1.1 NRCA's Mandate.
By legislation passed in Parliament in April 1991, government of
Jamaica has endowed the NRCA with wide-ranging general powers to
manage and protect the country's natural resources, and particularly
to institute appropriate Per-mitting and Licencing procedures designed
to ensure that due consideration is given to conservation and environmental
protection throughout the planning and implementation stages of
development projects.
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1.2 The Purpose of This
Document.
In order to be able to more efficiently and effectively fulfill
its mandate, the Authority intends to publish a series of Guidelines
and Standards which will be made available to other Government of
Jamaica agencies and to private interests, including potential investors
in the various industrial sectors, to inform them of the relevant
obligations that will have to be satisfied in order for them to
obtain the construction permits and operating licences from NRCA
that are required by law.
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1.3
The Specific Types of Facilities Covered by These Guidelines.
This document offers guidance on the permitting process, and the
engineering aspects, of projects involving the presence of pipelines
and cables in the coastal zone -guidance
that is intended to eliminate or mitigate the potentially harmful
impacts that installation and operation of such elements could have
upon the marine environment.
The more common types of pipelines and cables that will be dealt
with are:
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2. THE COASTAL ZONE
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2.1 Definition of
the Coastal Zone
There is no single all-purpose definition of the coastal zone that
is internationally current. Definitions cover spatial areas ranging
from relatively narrow marginal strips of land and sea, up to broad
concepts encompassing even the watershed areas which drain directly
to the sea as well as the entire marine area from the shoreline
out to the edge of the continental shelf.
The working definition used by NRCA for the Jamaican coastal zone
is the area of sea and seafloor extending from the high water mark
out to the edge of the island shelf.
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2.2 The Importance
of the Coastal Zone
The coastal zone is ecologically and economically precious to Jamaica:
§ provides feasible locations for
ports and other vital industrial installations;
§ offers natural resources that
enhance recreational/tourism use.
However, in Jamaica, as in many other developing countries, the
quality of the natural resources of some coastal zone areas is being
increasingly degraded due to high population pressure and intensified
usage by industrial, commercial and recreational interests.
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Relevant Ecosystems and Other Resources of the Coastal Zone
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2.3.1 Coral Reefs
Coral reefs are tropical, shallow water ecosystems that typically
consist of carbonate rock with interspersions of rubble and
sand. Growth of corals requires clear, warm, aerated and nutrient-poor
conditions.Coral reefs perform many critical environmental functions:
§ Their structure allows them
to withstand and dissipate strong wave action, thus protecting
land, islands, and beaches from wave damage and shoreline
erosion.
§ They provide habitat for
animals and plants thereby accumulating nutrients for rather
complex food webs.
§ Coral reefs have the highest
reported species diversity of any marine ecosystem, thus
they play a substantial role in the preservation of global
biodiversity.
§ Some medicinal drugs and
other natural products can be derived from coral reef organisms.
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2.3.3 Coastal Wetlands
Wetlands are transitional areas between terrestrial and marine
systems, in which the water table is usually at or near the
surface, or the land is covered by shallow water. Coastal wetlands
act as a buffer between land and sea in a number of ways, such
as protecting the land from sea storms. Wetlands are nutrient-rich,
provide protective habitat, and are productive nursery areas
for fish and shrimp.
In regard to vegetation, the marine wetlands around Jamaica's
coastline usually contain seagrass beds and varieties of mangroves.
The word "mangroves" refers either to the constituent
plants of a tropical intertidal forest community, or to the
community itself. Many mangrove trees can grow in both saltwater
and brackish environments.
Mangroves provide habitat for many terrestrial and aquatic
animals and serve as temporary habitat for spawning, nursery
and feeding. They are important in the preservation of biological
diversity for many species of plants and animals. Mangrove forests
protect coastal areas against erosion and mangrove vegetation
filters and purifies water.
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2.3.4 Muddy and Sandy Bottoms
These ecosystems are constituted by fine muddy or coarser sandy
sediments overlain permanently or temporarily by water. The
bulk of these sediments is derived from rivers, bedrock and
reefs. The composition of the sediment that is eroded transported
and deposited in the coastal zone can be further modified by
inputs of organic matter contributed by adjacent wetlands.
Muddy and sandy areas serve as nursery grounds for rapidly
growing juveniles of many valuable fishery stocks, particularly
in shallow water by offering conditions such as reduced predation
and greater food availability.
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2.3.5 Rocky Coasts
Rock commonly forms the coastline wherever there is little
sediment inflow, and wherever the onshore elevation is relatively
high and wave action strong. Shoreline rocks and boulders are
sometimes heavily colonized by large algae.
Rocky coasts provide environmental goods and services and perform
important biological functions such as:
§ Provide surfaces for attachment
of productive marine algae and filter-feeding invertebrates
such as oysters;
§ Offer feeding or breeding sites
for many rare, endangered or protected sea-birds;
§ Help dissipate wave energy and
thus protect shore sediments and soils from erosion by sea.
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3. GUIDELINES FOR PRELIMINARY
PLANNING
The planning for a project is usually carried out in two distinct
stages, viz: i). preliminary studies; and ii). detailed design.
This chapter offers general guidelines in relation to preliminary
planning for the installation of pipelines and cables in the coastal
zone.
Guidelines for detailed design will be presented in a later section.
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3.1 The Objective of Preliminary Studies.
The objective of preliminary studies is to identify possible
sites/routes for the pipeline or cable, and to try to find out
as much as possible about the key engineering and environmental
issues associated with each possibility. The purpose is to develop
clear bases for comparative judgements and evaluations, leading
up to selection of a preferred site/route that is technically,
economic-ally and environmentally feasible.
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3.2 Screening of Possible Sites/Routes for Pipelines and Cables
The screening that is usually done during preliminary studies
hopefully will result in the identification of a number of alternative
site locations and routes that are potentially viable, when considered
in light of appropriate technical and environmental criteria.
In identifying possible sites/routes, it is recommended that
an environmental screening checklist be used. The checklist given
in Table 1 below, highlights the typical environmental concerns
which should be taken into account in the siting/routing of pipelines
or cables in the coastal zone.
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Table 1
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General Environmental Screening Considerations for Site
Selection and Route Evaluation for Installation of Pipelines
and Cables. |
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AREAS of CONCERN SCREENING CONSIDERATIONS
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| Route Alignment |
§ Choose routes that will have the
least negative impacts upon critical habitats or spawning grounds;
migration routes; aquatic vegetation; threatened, rare or endangered
species.
§ Avoid passing through coral reefs.
§ Avoid passing through existing
or proposed marine parks, dive sites, community bathing beaches.
§ Avoid passing through locations
of archaelogical, historical, cultural or paleontological interest.
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Shoreline Stability
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§ Avoid locations where the shoreline
is undergoing erosion, accretion, progradation.
(Wherever shorelines are unstable, buried
pipelines/cables could subsequently
become exposed, or more heavily over-burdened than anticipated,
leading to disruption).
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| Seismicity |
§ Avoid sites that are close to
known active geological faults.
(If pipelines/cables are located near to active
geological faults there will be increased risk of disruption due
to earthquake).
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| Bathymetry |
§ What are the natural seafloor
gradients?
(Uneven, steeply-sloping seafloors can give
rise to integrity and stability problems for pipelines and cables
laid thereon).
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| Seabed Soils |
§ What is the nature of existing
seafloor soils, origin of the superficial deposits?
§ How deep to bedrock?
§ Is the material of a type that
would present extraordinary difficulties for trenching and burial
of pipelines or cables in the nearshore area?
(The answers to the above questions will be
very important in determining whether it will be technically and
economically feasible to bury portions
of the pipeline or cable).
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| Wind, Waves, Currents |
§ Is there on-going shifting of
seafloor sediments and seabed contours, due to strong wave action
and bottom currents?
(The degree of exposure to strong wave and
current action can be a very important
factor in site/route selection for pipelines or cables
in the coastal zone, as under such conditions
extra engineering measures will
have to be applied in order to preserve integrity.
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3.3 Typical
Environmental Impacts from Installation and Operation of Some Common
Types of Pipelines and Cables in the Coastal Zone
The next step in the process of preliminary planning, after identification
of possible sites/routes, will be to analyse and compare the main
advantages and disadvantages of each potentially viable site/route.
From this process, a preferred site/route will be identified, one
that is satisfactory in terms of the critical technical and environmental
considerations.
In evaluating alternative sites/routes, the potential impacts upon
the biologi-cal, physical and cultural environments during construction
as well as during operation, should be compared. Alternative
sites or routes can also be assessed on the basis of minimizing
or eliminating potential impacts by use of acceptable mitigation
techniques.
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3.3.1 Impacts during Construction.
It is almost inevitable that there will be some damaging impact
upon the coastal zone environment during installation of pipelines
or cables. The de-gree of impact will mainly depend upon such
important factors as: the type and size of the pipelines or cables;
whether buried or laid on the surface; types of plant and equipment
and the installation techniques used. The follow-ing are some
typical construction impacts that developers must strive to avoid
or minimize or mitigate:
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3.3.2 Impacts during Operation.
Table 2 below indicates some of the more damaging types of environmental
effects that operation of some common types of pipelines and cables
can cause in the coastal zone.
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| Table 2 |
Some Typical Negative Environmental Impacts from Operation
of Pipelines and Cables in the Coastal Zone. |
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Type of Pipeline or Cable SOME TYPICAL NEGATIVE
ENVIRONMENTAL (by function) IMPACTS DURING OPERATION
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| Sewage Outfalls |
§ If the effluent being discharged
should contain excessive levels of pollutants, this could cause
serious eutrophication in the receiving waterbody if the waterbody
does not have the capacity to handle the inflow of pollutants.
Eutrophication leads to damage/destruction of existing fisheries
resources, seagrass, coral, mangroves.
To avoid such disastrous consequences, sewage
effluent must be ade-quately treated prior to discharge, and outfall
pipelines must be taken to termination points where the discharge
plume will be effectively dispersed without causing damage to
marine ecosystems.
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| Pipelines for oil and other petroleum products |
§ Spillages are virtually inevitable,
most commonly through accidental damage to pipelines, or faulty
procedures in coupling/uncoupling hoses for ship-to-shore transfer
of products.
Spilt oil can cause serious damage by smothering
marine ecosystems. Appropriate contingency provisions must be
made to ensure that an adequate emergency res ponse capability
is maintained at the site to deal with oil spillages.
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| Power Station Cooling water Pipelines |
§ The elevated temperature of cooling
water discharge plumes can make this type of effluent damaging
to temperature-sensitive marine ecosystems, e.g. coral reefs.
In order to obtain NRCA approval for installation
of cooling water pipes, it will be necessary for Developers to
satisfy NRCA that the proposed discharge plume will not
impact negatively upon any downstream marine ecosystems. Sea-chests,
and the ends of intake pipes must be properly screened
so that small fish are not sucked into cooling-water systems.
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| Power and Telecommunications cables |
§ Cables which are oil-cooled can
cause environmental damage should they be accidentally damaged.
Apart from this, if cables are adequately buried they should have
no significant operational impact in passing through the coastal
zone
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3.4 Sources
of Information for Preliminary Studies
At the very start of the planning process, the Developer will naturally
seek to gather up all the existing site maps, charts and whatever
other relevant infor-mation might be available, and try to glean
a sound appreciation as to what are the likely key engineering and
environmental issues that will have to be dealt with.
Project sponsors can expect that in Jamaica they will be able
to gather con-siderable information from the following sources,
which they will be able to use for carrying out meaningful preliminary
studies for installation of pipe-lines and cables in the coastal
zone.
§ Survey Department -comprehensive
topo/cadastral maps, some hydrographic charts;
§ Geological Survey Department
-geological maps, reports, earthquake hazard map, hurricane
hazard map;
§ Government Meteorological Office
-weather data:wind, rainfall waves, tides, storm surge;
§ Seismic Unit, -various publications
on University of the West Indies, Mona -local & regional
seismicity;
§ Underground Water Authority
-underground water resources, flood maps.
§ Natural Resources Conservation
Authority - the NRCA Docucentre is the most im portant source
for information on govternment environmental policy, national
environmental Standards, and the Permitting process.
§ Port Authority of Jamaica -the
PAJ is government’s chief Agency for the regulation and
monitoring of all maritime activities and Dock and
Harbour constructions.
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3.5
Project Sponsors Should Seek Early Contact With Local Interest
Groups.
Project sponsors are advised that they should make it an essential
component of their preliminary studies to initiate contact with
local interest groups, and seek to involve them in the selection
of suitable sites/routes for their projects
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4. PERMITTING PROCEDURES
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4.1
Project Sponsors Should Make Early Contact With NRCA
Certain types of activities in the coastal zone will give rise to
particular ef-fects, and therefore it is important for all concerned
to be aware of the parti-cular types of negative effects that are
likely to arise from a given type of project. Project Sponsors are
therefore urged to make contact with NRCA from the very earliest
stages of project planning and to seek advice from the Authority
in regard to the nature of the particular environmental issues that
will have to be satisfactorily addressed in order for them to obtain
the necessary permits.
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4.2 Project
Sponsors May Be Required To Hold Public Meetings To Inform
Local Communities Concerning Their Proposals
4.2.1 The NRCA may require that applicants for permits to install
pipelines or cables in the coastal zone, consult with other government
agencies, and with local interest groups that may be adversely affected.
Project sponsors must be prepared to fulfill, as part of the permitting
process, NRCA requirements to hold "town meetings" to
give opportunities to local populations to voice their opinions
concerning proposed projects.
4.2.2 To foster genuine people participation, the site selection
process itself must be comprehensive, clearly laid out, and presented
in understandable language. Project sponsors should regard town
meetings as very valuable opportunities for open consultations
with local communities. The adoption of logical, comprehensive
and open procedures in site selection may well produce the most
satisfactory results for project sponsors as well as the public.
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4.3
NRCA’s Environmental Review and Permitting Process
Any project in the coastal zone which has the potential of affecting
the environment must be referred to NRCA for consideration. Documentary
information concerning NRCA’s Environmental Review and Permitting
process can be obtained from NRCA upon request.
The NRCA’s Review Process, leading up to either the granting
of a Permit for implementation, or denial of the project, is illustrated
in the flow chart given overleaf, and the salient points of the
review process are explained below.
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