US Consultant Assists ET
Environment TOBAGO has been working towards finding solutions to the problem of coastal sewage pollution for the past three years.
Mr. Greg Brown, an engineer from the Florida Department of Environmental Protection spent a week in July studying Tobago’s sewage disposal systems. His trip was sponsored by the Florida Association of Volunteer Agencies for Caribbean Assistance (FAVA/CA). Environment TOBAGO had asked FAVA/CA for technical assistance in evaluating sewage disposal practices in Tobago and in formulating solutions to the problem of coastal water pollution.
Mr. Brown inspected the package treatment plant at Coral Gardens Housing Development. This plant receives wastewater from approximately 150 households. He concluded that the plant appears to be providing minimal, if any, treatment. None of the automatic control systems were functioning, so a maintenance man from the National Housing Authority was turning the aeration pumps on and off manually. These pumps provide the oxygen needed by the bacteria which break down organic material in the tanks. Without oxygen the bacteria begin to die off. Sludge, the highly toxic solid material that settles to the bottom of the tanks, was being released onto the ground next to the plant.
He noted at Buccoo Village that only a thin layer of topsoil covered the coralline limestone underneath. He wondered how proper soak-aways could have been dug into this rock. He said that this limestone may be very porous, allowing untreated sewage to pass quickly to the underground water table.
He met with a private Tobago contractor who explained traditional Tobago residential septic system construction and concluded that the majority of Tobago’s residential systems are most likely functioning poorly, if at all. He explained that septic systems need to be designed according to the permeability of the soil and other factors. He demonstrated a simple low-cost method of measuring permeability called a percolation test. The heavy clay soil in the area where the demonstration was conducted did not appear to allow for any percolation and therefore a soak-away would not work properly if installed in this soil.
Demonstrating the percolation test
He met with Secretary of Health, Ms. Judy Bobb, who said that the THA was aware of the sewage pollution problem in Tobago and that two committees had been set up to deal with the problem. She also expressed willingness to work in partnership with Environment TOBAGO to work towards solutions.
Environment TOBAGO advocates the need for immediate action in regard to the problem of coastal water pollution in Tobago. We thank Mr. Greg Brown and FAVA/CA for helping us move forward in a positive direction towards finding and implementing solutions.