Mr. Mukesh Ganesh
Engineer, Water & Sewage Department, Min. of Communications & Works
PO Box 130, Roadtown, Tortola, BRITISH VIRGIN ISLANDS
Tel: 284-494-3416/7 ext. 5797, Fax: 284-494-6746, Email: water@caribsurf.com

The British Virgin Islands (BVI) is made up of about fifty small islands located in the Lesser Antilles in the Caribbean Sea. The largest island, Tortola, is only twenty-four square miles in area with it’s capital Road Town. Other islands that have some significant population includes Virgin Gorda, Jost Van Dyke and Anegada. Public water supply is only available in Tortola and Virgin Gorda and two separate sewerage systems are in Tortola. The BVI has a current population of 19,482.

Sewage disposal in the British Virgin Islands has classically been by either direct dumping in the ocean or by the use of septic tanks and soak away or field beds. The direct discharge of raw sewage to the ocean is practiced in the BVI by residences and businesses along shorefronts and by yachts anchoring in the many harbours and bays. In these areas where swimming, snorkelling and scuba diving are tourist pastimes, direct discharge of raw sewage to the sea is not entirely appropriate. In the capital, Road Town, sewage is collected by gravity sewers and channelled to wells from where it is pumped into the ocean. Intermittent disinfection of the wells is carried out.

In many other areas, there have been ongoing complaints of flows of septic tank effluent across public thoroughfares and into neighbouring properties. In the BVI, there are few, if any, areas where simple land disposal of sewage would be practical, in part due to the shallow depth of topsoil throughout the islands. Recently the first public sewage treatment plant with capacity of treating 45,000 gallons per day has been commissioned to serve Cane Garden Bay in Tortola. This plant is a sequencing batch reactor (SBR) with three parallel tanks. In Anegada pit latrines are used in addition to water closet facilities and these are now contaminating the few water wells the residents are using to obtain their fresh water supplies. Anegada is a flat island made up of coral limestone and it is difficult to construct septic tanks and pits for latrines.

Sewage can be treated to various extents and by a variety of different methods prior to disposal. These range from a total lack of treatment to full biological treatment with tertiary treatment for disinfection. Some options of technologies available are:-

- disposal of untreated sewage,
- septic tank and on site disposal,
- chlorination and disposal of sewage,
- primary treatment mainly by settling in clarifiers or sedimentation basins,
- secondary treatment. Some of the more commonly used biological processes are:-

- activated sludge process including the sequencing batchreactor,
- attached growth biological processes (e.g. biodisccontactors and trickling filters),
- aerated lagoons,
- stabilisation / oxidation ponds.
- tertiary treatment,
- combinations of the above, i.e., primary plus tertiary.

The economy of the BVI is very dependent on tourism and it is the duty of the Government to ensure that the environment is kept clean so that more tourists can be attracted.

Fecal colifor bacteria, an indicator of pollution caused by the presence of human waste, have been monitored. Currently the Department of Conservation and Fisheries monitors the coastal waters of the BVI. A 1988 report by Dillon Consulting Engineers of Canada referred to a monitoring programme that identified Road Town and Cane Garden Bay as being the most polluted areas in the territory. Government has since installed the treatment plant at Cane Garden Bay and is formulating plans for treating sewage in the Road Town area. Since the installation of the sequencing batch reactor at Cane Garden Bay, no results have been released from that area.

The Government of the British Virgin Islands has an extensive plan to improve sewage collection and disposal in the territory. Besides the new system that was commissioned in Cane Garden Bay in August 1998, the following new works are planned:-

- design and construction of a new sewage collection and treatment system for the eastern end of Tortola. Here the treated
        effluent would be available for use as irrigation at the nearby Agricultural Station, which uses expensive potable water for
        irrigation presently. Also the treatment plant will help to eliminate the evidence of contamination arising from sewage
        discharge into the ocean along the total length of the East End settlement. The sewage generated from the planned
        expansion of the airport at Beef Island will be treated at this plant.

- design a construction of a new sewage treatment plant in the vicinity of Road Town to treat the sewage before disposing
        the effluent to sea. Minimal modifications will be needed on the existing sewer system and secondary treatment would
        eliminate problems of contamination. The possibility of water conservation and reuse hinges on the existence of an
        adequate treatment system.

-    design and construction of a new sewage collection and treatment system for the Valley, Virgin Gorda.

The following have to be taken into account to adopt, apply and operate environmentally sound technologies for domestic and industrial wastewater treatment in the BVI.

-    the primary concern is to produce an effluent that will not adversely affect the environment especially in the contamination of
     the many beaches and harbours around the territory. The technology selected may need to cater for tertiary treatment, thus
     a high quality of effluent.

-    desalinated water is supplied for public’s use and is quite expensive and with tertiary treatment of the effluent there is the
     possibility of recycling the water for domestic consumption or at least used for irrigation purposes.

-    the disposal of sludge is also of paramount importance and the Government is now making initial preparations to have a
     suitable area designated for the construction of a drying bed. Septage from septic tanks and sludge from waste water
     treatment plants should be dried and can be used as a soil conditioner in agriculture.

-   that septic tanks with soak away are not an effective means of wastewater treatment and disposal in the BVI because the
    top soil is too thin for effective biological breakdown of the effluent.

-    the importance of monitoring cannot be over emphasised. More detailed tests for coliforms and nutrients should be carried
     out at more locations. The Ministry of Natural Resources and Labour, Department of Conservation and Fisheries are doing
     these tests.