Please use this identifier to cite or link to this item:
http://saruna.mnu.edu.mv/jspui/handle/123456789/4865
Title: | Environmental impact assessment for the proposed sewerage system in Nolhivaram, Haa Alifu Atoll, Maldives |
Authors: | Sandcays |
Keywords: | Sewerage systems Legislative and regulatory considerations Existing marine environment Existing terrestrial environment Existing socio-economic environment Constructional impacts Operational impacts Mitigation measures Environmental monitoring Environmental impact assessments |
Issue Date: | Jun-2016 |
Citation: | Sandcays. (2016). Environmental impact assessment for the proposed sewerage system in Nolhivaram, Haa Alifu Atoll, Maldives. Male': Maldives |
Abstract: | This report discusses the findings of an environmental impact study under the proposed
sewerage system project at HDh. Nolhivaram. The project is proposed by Ministry of
Environment and Energy.
The project entails establishment of a proper island-wide sewerage system with a sea outfall.
The proposed project will involve installing a pipe network to collect sewage from all the
households on the island and necessary pumping stations. Currently raw sewage is disposed
onto the ground via house-level soak-pits; polluting groundwater greatly. The proposed outfall
will pump wastewater beyond the house-reef at over 7m depth.
A number of alternatives to the proposed project components have been identified in this
document. Of these, the preferred alternative is to change the outfall location directly north of
the island. It is also proposed to consider a treatment plant in the design, though the
consultants are of the opinion, proposed system without a treatment plant but alternative
outfall location is the best option. Other alternatives include considering different disposal
options; ground and lagoon, which are not recommended for reasons of greater environmental
pollution.
Environmental impacts were assessed for both the construction and operational phase of the
project. Most of the environmental impacts identified for the construction phase of the project
were minor negative; these include excavation and related difficulties to road uses,
sedimentation from installing the outfall and temporary salinization of groundwater from dewatering
to lay out the pipe network and pump stations. However, the impacts identified for
the operational phase of the project were mostly moderate to major positive; improvement of
groundwater quality from stopping the current sewage disposal practise and reduction of
related health hazards. Disposal of sewage via a sea outfall is considered as minor negative
impact while the lack of multiple lagoon outfalls will help to improve the quality of the
lagoons which is a primary recreational area of the island.
The main mitigation measures for this project during the construction phase are similar to
other sewerage projects such as dust control plans, working during low-tide during pipe
installation and rigorous supervision. In case of deterioration of groundwater quality due to
potential dewatering during construction of lifting stations in residential area, measures to
water plants in the area that may be affected due to dewatering shall be in place. The design
shall also ensure that dewatering is minimized. As for the operational phase trained
maintenance staff to service the sewerage system and regular check-ups has been suggested in
addition to monitoring water quality as well as reef health for potential impacts. Increasing
awareness on groundwater conservation and promoting sustainable groundwater aquifer
management, especially the skimming well technology has been suggested.
The Proponent is willing to undertake monitoring during and after the construction phase in
addition to undertaking the mitigation measures proposed by the consultants.
In conclusion, it appears justified from a technical, administrative and to some extent
environmental point of view, to carry out the proposed sewerage system development project.
The alternative of wastewater treatment will involve greater operational costs; therefore, it is
recommended to proceed the project as proposed while keeping the option open for future
wastewater treatment, as and when required. |
URI: | http://saruna.mnu.edu.mv/jspui/handle/123456789/4865 |
Appears in Collections: | ތިމާވެށި Environment A
|
Items in Saruna are protected by copyright, with all rights reserved, unless otherwise indicated.