Development Of Marina Barrage Around Marina Bay Environmental Sciences Essay

Environmental Impact and Assessment (EIA) is the evaluation of the possible impacts on the environment resulting from a proposed project. We are going to discuss how the construction and operation of the Marina Barrage and development around Marina Bay can lead to destruction of reef and coral growth.

The construction and operation of marine Barrage and development will affect the water quality of the marine bay. This is because these developments and construction will lead to decreased flow of water into the sea. This may also lead to change in downstream water quality and conditions. The salinity of the water body may be altered by these developments and constructions. Reduced water flow may result in decreased nutrients in the sea and built up of silt which may result in the long term disturbance of the ecosystem. Eutrophication is also likely to result thus destruction of coral and reef growth (2).

The growth of algae on top of the corals may end up killing them since sunlight is blocked which is necessary for the process of photosynthesis. Since this Marina Barrage is also meant for tourist activities, it may end up with destruction of corals for tourism purposes. Waste dumping is also likely to increase and also increased of oil spills and other products during the construction. This may end up contaminating the water leading to the death of corals. Oxygen levels are likely to decrease resulting to death of coral reefs. Dredging and dynamiting process in this project may end up in the removal of materials from the living reef.

According to Cortés (2003), the development may lead to increased population which may result in increased pressure on the water resources. More corals are likely to be removed for purposes of souvenir, jewelry and other purposes. Turbidity is also likely to increase due to particles floating on water. This prevents light from penetrating the water and therefore the corals suffer. Corals always flourish in clean and clear water.

Construction can also lead to soil erosion. This results in more particles ending up in the water body which covers the corals. This ‘smoothers’ the corals and lead to their death. This is as a result of destruction of mangrove and other tree species which act as filters of sediments. In this case a lot of vegetation may be destroyed in constructing and developing marine barrage.

The corals are very important since they are a source of tourism and also help in controlling water currents, strong waves and storms. Reefs are also sources of medicine and are used in treatment of a number of diseases such as leukemia, heart disease and also treat ulcers. The corals also use carbon dioxide to form their shells and therefore in a way prevent and minimizes pollution (3).

During the development of marina bay, sediment plume monitoring of the dredging and reclamation works are done constantly as they are considered the top priority. Should an impact on coral reefs be anticipated, mitigation measures must be put in place to reduce or removed the impact. The sediment plume are monitored using a combination of desktop and field tools with the calculations of the daily spill coupled with the concentrations of the total suspended solids recorded by online optical sensors, secchi depth monitoring and water quality surveys. Water quality surveys to check the quality of water are also done constantly on a periodic basis to record the water quality conditions around the development site. Optical sensors were deployed on the seabed at various locations to monitor water quality. Turbidity, temperature, PH and dissolved oxygen levels are monitored by a combination of sensors so as to enable preventive measures to be undertaken. One problem faced is that the turbidity sensors at the site cannot differentiate between the loadings produced from dredging and reclamation actions, and natural variability in background conditions.

Lastly translocation measures were also considered and the corals situated directly below the development site were relocated to another pre-selected location. Separate study must first be carried out to define a suitable relocation site for it. One advantage of this mitigation measure is that translocated corals usually have high survival rate of approximate 90%. Divers involved in the relocation of corals must be properly trained so as not to damage the corals. Divers sometimes face difficulty due to poor visibility caused by silt suspended in the water. Visibility may be so bad that divers may have to bump into coral to notice them. This will reduce the number of coral reef succumbing to death.

New mitigation measures that can be implemented include the creation of artificial reefs to provide compensatory mitigation for impacts to hardbotton habitat from construction activities. The selection of materials for artificial reef construction is important. The use of hard and soft corals, sponges differ and factors including the depth of water in which reefs to be built and the availability of crevice space for shelter must also be considered.

Another measure is the use of surveying techniques in the design and siting of costal construction projects to avoid and minimize adverse environmental impacts. Recent years have seen the advances in high-definition surveying technology and 3-D laser scanning technology which helps in greater confidence in survey data, reduced need to return to site to double check or acquire additional data, faster delivery of completed survey, the richness and quality of the survey is improved (4). One example is the Laser Airborne Depth Sounder (LADS) that is useful in identifying the seafloor topography and location of hardbottom areas which allows for improvements in design, siting and impact minimization. However this technology remains costly compared to ground survey techniques.

In conclusion, the construction and development of Marina Barrage around Marina Bay in Singapore is likely to result to destruction of coral reef. This may lead to death and decreased numbers of the coral reef. The impacts may include change in water quality, eutrophication, and reduced flow of water which in a way will affect the growth of coral reefs.