SEI
ENVIRONMENTAL IMPACT ASSESSMENT
prepared by:
SUSTAINABLE ECOSYSTEMS INSTITUTE
SEIENVIRONMENTAL IMPACT ASSESSMENT
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The Little Bay Emergency Jetty project has been proposed and developed in response to the volcanic crisis in Montserrat. The project goal is to provide an emergency evacuation jetty (phase 1) and a cargo facility (phase 2) in the north and safe zone of the island. Any project of this nature requires an EIA (Montserrat Physical Planning Act ). The EIA for the project was undertaken by Sustainable Ecosystems Institute (SEI). The scope of the work was agreed with Physical Planning Unit (Montserrat). L.G. Mouchel and Partners (the engineering company responsible for jetty construction) and SEI. The goal of an EIA is to answer three main questions: What is the present state of the environment? What will be the effect of the new development on the environment? Considering the costs and benefits, should the project go ahead, and if so what mitigation steps should be included to minimize impacts?
This EIA first develops a profile of the marine and terrestrial environments, then discusses the impact of the jetty construction on the environment and on the proposed tourism plans for Little Bay (in accordance with EIA scope of the work), and finally recommends mitigation and monitoring procedures.
Little Bay is located in the northwest section of the island, bounded by Rendezvous Bluff on the north and Potato Hill on the south. The government of Montserrat owns some 230 acres in the Little Bay estate between Davy Hill in the south and Rendezvous Bluff in the northwest. The north and eastern parts of the site are steep terrain covered by dry woodland. The site has been repeatedly cleared for agriculture, timber exploration, or in anticipation of future tourism development. The conservation and tourism potential of little Bay has been long recognized. Since the 1980's there have been formal plans to develop little Bay as a tourism destination. These plans have been endorsed by the Montserrat Physical Plan (approved 1995) and the Development Strategy for the North which proposed the development of Little Bay as an ecotourism destination.
Marine Environmental Profile
We carried out a marine environmental profile of Little Bay by surveying the marine life in the bay, using standardized scientific techniques for tropical marine ecosystems (English et al 1994). These included manta tow surveys, quadrat and transect surveys of fish, marine plants, corals, and other invertebrate life. Results were analyzed and presented in figures and tables. Species diversity is made up of the number of species and the number of individuals of a particular species in a biological community. We calculated a species diversity index for the proposed jetty locations at Little bay and compared it with 2 other pristine reefs in the west coast. We have been studying the reefs since 1995 using the same scientific techniques and this allowed us to compare Little Bay with other marine sites in Montserrat.
Little Bay is a sandy bay with rocky outcrops on the north and south shores. Along the north shore, a series of boulders interspersed with sand extend from the cliff to 50 m offshore. Corals, sponges, plants and other invertebrates settle on boulders. The persistence of the reef community is dependent on boulders which provide a suitable hard substrate for settlement and growth. Close to the beach, (proposed North Central jetty location) the reef is poorly developed. This is because boulders are confined to shallow water and there is constant sediment and sand scour. Some schools of fish use this area for feeding (e.g. juvenile grunts, and wrasses). The direct impacts of the jetty on this area will be lower. In area 2, the proposed location for the north jetty, the reef is better developed and there is a high diversity of corals, and fish life. This area is a nursery ground for fish, juvenile lobsters, and urchins. Juvenile fish and lobsters that settle in this area subsequently migrate to deeper waters as they mature. For commercial species, such as lobsters, this reef is important to the fishery. It is also regionally important, as it appears to be one of the few suitable nursery grounds in the region. The boulders are additionally a prime habitat for octopus. During our surveys we recorded one specimen of the gaudy brittle star. This is a recently discovered species and until now, was only known from deep waters off a few other islands. Around the headland there is an extensive reef area, with a well established coral reef. The density and diversity of fish in this area is high, and the persistence of this reef is tied to the water flow pattern that brings a localized current of water northwards around the headland. The high abundance of plankton-feeding fish on the edge of the reef indicates that this is a productive part of the bay. On the south shore a new reef is developing on the boulders that were scattered on the seabed during Hurricane Luis. Further south there are established reefs off Potato Head. The central portion of the bay is sandy, and flying gunnards, stingrays, sand-dollars, helmet shells, and lug worms are abundant on the sea floor. In comparison to nearby pristine sites, the north location and bluff areas at Little Bay are ranked highly. In total, we recorded 16 plant species, 63 fish species, 23 coral species, and 83 other invertebrate species.
Human impacts on the marine ecosystem in Little Bay are currently low. There is some fishing off the bluff, and SCUBA diving mainly from the south shore. Fishermen moor their boats in the sandy bay. Currently any fish landed must be brought ashore on the beach, which can be difficult in high swells.
Terrestrial Environmental Profile
We developed a terrestrial environmental profile by surveying the plant and animal fife in Little Bay area. Our goal was to describe the biological communities that are present and to identify any special features. This will allow us to determine the likely consequences of different construction options. We focused on target and indicator species. Indicator species are responsive to environmental and community conditions, target species are important because of rarity, cultural, or attractiveness to tourists. We surveyed and described the following group of organisms: land plants, butterflies (indicator species), land crabs (target species) birds (indicator and target species) bats (target species). We carried out our surveys using standard scientific transect and quadrat methods. For seabirds, we made two aerial surveys of the island to determine the importance of the Little Bay area to the seabird community. We made numerous visits to the bat cave at the western edge of Rendezvous.
The terrestrial community at Little Bay encompasses several biological communities. A narrow strip of beach vegetation comprising herbs and Acacia is confined to the southern part of the beach. Immediately east of the herb community is a back beach community of shrubs and trees. In the southern areas this includes sea-grape. In the northern wetter section Manchineel dominates. East of this community the land has been heavily grazed. A number of palms have been retained. In this area land crabs have made numerous excavations. In the easternmost section of the survey area pasture land is interspersed with occasional thorn bushes. A shrub community fringes the pasture land and continues along the foot of Drummond Hill spur. The hillside itself is characterized by a dry scrub community including cactus. None of the plant species are either rare or of great conservation value. Most of these species are widespread and found in similar habitats throughout Montserrat. Of particular interest is the dominance of introduced weeds and grasses. This is typical of heavily disturbed communities which are affected by grazing as is the case at Little Bay. 15 butterfly species were recorded. While none of the species are rare, they are broadly indicative of the conservation value for a wider set of organisms. On this basis butterflies demonstrate that the riparian and manchineel areas are of highest conservation value.
On a larger scale, while most of the vegetation on site is non-native, or weedy, there are a few animal populations of value. On site we have identified three areas of interest, which contribute to biodiversity. These are the immediate beach area, the riparian zone, and the palm area which contains large numbers of land crabs.
The most important biological resources are located off-site, at Rendezvous Bluff. The roost of the bat Brachyphyllum cavernarum is of prime conservation value. in 1995 it was discovered that just two roost sites were used by this species. One of these sites is close to Chances Peak, and is known to be heavily ashed. It is probable that the roost at Rendezvous Bluff now represents the only safe location for the species on the island. This species is susceptible to disturbance at roost sites. Following the presumed destruction of the Mosquito Ghaut site, it is possible that Rendezvous Bluff would now be ranked as the single most important roost site on the island.
Rendezvous Bluff is also of considerable importance as a breeding ground for Tropic Birds. We estimate that between 25 and 50% of the island's population nest at this location. Loss of this colony would seriously harm the population on Montserrat. It is unlikely to lead to local extinction, because of the availability of other nest-sites.
Archaeological Site
The archaeological site at Little Bay is known from the ghaut area and dates from circa A.D. 500-1500. The main location is at the end of a streambed that drains from the NE and near the streambed coming from SE. There is a major concentration of shards in the bank on the northern side of the north stream. The maximum site dimensions are about 50 x 100 meters. Given the relative scarcity of pre-Columbian material on Montserrat, this site must be seen as having great importance.
Environmental Impacts
The development of a cargo jetty at Little Bay will impact both the marine and terrestrial community. The severity of the impact win depend on the design and location of the jetty. There are four proposed jetty locations, From a biological and tourism perspective, the southern location is best for the jetty. This would involve minimal disturbance to the environment and beach area. For instance no additional road is needed. From environmental and tourism perspectives sites are ranked from 1 to 4 with 1 being the least impact. Southern location 1. Central location 2. North central location 3. Northern location 4. From a wave action criteria (which affects the ability to use the jetty) the ranking is the reverse with the north location being favored.
From a marine environmental perspective our main concerns were the destruction of the northern reef (an important nursery ground) either directly by jetty construction or indirectly through limiting water flow which interferes with feeding and survival of marine organisms. A further concern is that reduced water flow will lead to sedimentation on the reefs and kill sensitive marine organisms (e.g., Rogers 1990, Mattia 1996, McAllister 1996). Additionally a solid structure can block water and interfere with littoral processes leading to sediment build up and that this will destroy the corals and fish life in the area (e.g. see Krauss, 1988 The effects of seawalls on the beach; and US Army Corps of Engineers, 1990, Midscale physical model validation for scour at coastal structures, and Kraus et al, 1989, DUCK85 Surf Zone Sand Transport Experiment).
In the draft EIA there was only one proposed design, that of a modular structure using corrugated steel shipping containers. We found this design unacceptable from pollution, safety, visual appearance, and environmental considerations. In response to this concern, Mouchel and Partners developed a precast concrete design with at least 10% of the space open for water flow. This new design removes the pollution, safety and visual problems, but we are awaiting details from Mouchel regarding water flow amounts.
In the marine environment we expect the following impacts:
1. Jetty construction at the north, north-central or southern location will destroy corals on either side of the construction process. We expect that corals in 50 meters to either side of the construction will die.
2. The jetty will not interfere with fishing in the bay, but will have a positive impact of providing landing facilities for fishermen and may encourage additional fishing in the area.
3. The use of the jetty as a cargo facility is likely to lead to increased garbage on the reef.
4. Depending on the final design the jetty may or may not retard water flow.In the terrestrial environment we expect the following impacts:
1. Construction of a temporary road for construction purposes would permanently and unnecessarily damage biological and amenity resources.
2. Construction of a freight holding facility in the north will have permanent negative environmental effects. A location to the south will have less effects, presuming that the facility is indeed temporary. If the facility becomes permanent, it is incompatible with the development strategy for the site or for the region.
3. Archaeological resources may be damaged by construction in the north.
4. No prime biological communities on-site will be affected by development. There are several resources that should be preserved to maintain biodiversity, and attractiveness to ecotourists.
5. Prime biological communities occur nearby off-site. These may be affected by development (disturbance). However such disturbance can be minimized to reduce environmental impact.
6. Of the four locations that are under discussion, the southern option has clearly the least impact on the environment. The central option has major impacts on tourism development, and may destroy the beach, including important habitat for turtles and land crabs. The north-central and north options have more extensive impacts. The north-central location is preferable to the northern location, because of disturbance to wildlife at Rendezvous Bluff.
7. If either the north or north-central location is chosen, the access road will have less effects if it is constructed along the base of the Drummond Hill spur, and uses a bridge to cross the ghaut. Damage to the riparian area should be minimized.
8. Any development at Little Bay will increase use of the site, and will add pressure for future developments in the area, and further north in areas destined for ecotourism.Mitigation and Monitoring
Mitigation and monitoring are essential components of the construction project as they are the only ways of minimizing damage to the marine environment. We recommend the following mitigation and monitoring methods to minimize environmental damage and to ensure that the site is preserved for future tourism plans. Mitigation and monitoring can provide valuable information for deciding future planning and development strategies. A full description of mitigation and monitoring measures and costs is presented in Table 15 of this report. Results of monitoring and mitigation efforts should be reported to PPU, Montserrat National Trust, and MATE fisheries and agricultural departments.
Mitigation measures:
1. The jetty will destroy habitat, this can be replaced by providing a stone side on the jetty and scouring the surface to provide a rough surface more attractive for settlement of marine organisms.
2. Move large coral heads to the safe zone westward of the jetty, and move smaller boulders with established marine fife to the safe zone. This should be carried out with boat, diver, and biologists to minimize damage. This activity will also restore habitat.
3. Establish a snorkeling trail to the west of the proposed jetty, this will preserve the area for ecotourism
4. The area should be designated a nursery reserve to maintain the fishery and tourism potential of the marine habitat.
5. Following construction there should be a clean up of marine and terrestrial habitats
6. As the bay attracts more tourism, mooring buoys should be installed as part of the tourism development plan.Two specific actions can minimize damage during the construction process:
1. No dumping of garbage or waste in the sea
2. Moor boats and barges away from the reef (100 meters from the north shore) and to the south east of the proposed jetty.
In the terrestrial environment we recommend the following:
1. Sensitive road development is the most important step to minimize damage (See figure for proposed road area).
2. Bats are highly sensitive to disturbance, the jetty should not be placed in the flightpath of the bat population.
3. A site wide clean-up after construction will be necessary.
4. Disposal containers should be made available.
5. Two portable toilets should be made available.Remedial Actions:
1. Establish a nature trail in the riparian and manchineel sections of the environment (the high diversity areas). This will mitigate against further development in the area.
2. Purchase Rendezvous Bluff as a nature conservation area, encompassing the reefs of Little Bay and Rendezvous Bay. Public ownership can be an effective conservation measure (witness the international system of publicly owned parks).Archaeological Site The road should be constructed so as not to damage the archaeological site An archaeologist should investigate the site prior to construction, and be present during construction.
Monitoring is the only way to ensure that damage is kept to a minimum. It also provides valuable information on the success of the project and can help in future decision-making. We recommend the following monitoring activities.
1. Monitor sedimentation input and take remedial action if necessary.
2. Monitor the health of the reef ecosystem during and after construction. 3. Monitor the terrestrial environment, including the bats, birds, land crabs, status of the riparian zone.
4. Monitor human use including traffic, boat and fishing activity, recreational use, garbage and human waste.
5. Monitor the archaeological site.
Mitigation and monitoring efforts are designed to involve local organizations, agencies and groups as far as possible. Where the expertise is not available locally, outside consultants should be brought in and we have include local training in the budget. The total cost of litigation and monitoring (for a year after construction) is $123,772. These costs are revised upwards in light of comments from EIA review panel, and in light of additional construction time. This is small compared to the total budget for the project, and given recent construction estimates probably comprises less than 7% of the total construction budget. We consider this a small cost to maintain the environment and the future development prospects of Little Bay for Montserratians. In response to the draft EIA, Mouchel and Partners, and ODA agreed to some of the proposed Mitigation measures. We hope that they will agree to the revised costs as an integral part of the project to construct a jetty that meets the requirements of Montserrat and still allows for longterm development.
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