The public health assessment of excreta disposal in the Kingston, St. Andrew

ABSTRACT

Excreta disposal in the Kingston, St. Andrew Metropolitan Area was assessed by performing an audit of the processes carried out by the National Water Commission (NWC) and by conducting a survey in the Kentyre area. The audit took the form of a review that served to establish the extent to which processes at the NWC conformed to predetermined standards set locally by the National Resources Conservation Authority (NRCA) and internationally by the Environmental Protection Agency (EPA) and the United Nations Environment Programme (UNEP). This audit was facilitated by (a). site visits to sewage treatment plants operated by the NWC. (b). interviews with key personnel involved with excreta disposal (c). an examination of the records relating to the testing of the influent and effluent from sewage treatment plants within the Kingston, St. Andrew Metropolitan Area. A questionnaire instrument was administered to 40 randomly selected households in the Kentyre area to determine residents' knowledge, attitudes and practices towards excreta disposal. Of the 15 plants operated by the NWC in the KSA Metropolitan Area, five (33.3 percent) were primary facilities, nine (60 percent) were secondary and there was one (6.7 percent) was unsatisfactory and three (20 percent) were non-operational. All of the effluent from those plants that were operational was discharged into rivers and gullies and eventually flowed into the sea. Raw sewerage from plants which were non-operational also flowed into the sea. The site visits to the plants gave an insight to the operations at one tertiary and one secondary plant. These were in conformity with established processes for primary and tertiary facilities but there was concern practices such as the exposure of raw sewage to the environment and vectors, and unhygenic practices of workers. Monitoring of sewerage treatment plants of the National Water commission (NWC) is done both internally by the NWC and externally by the NRCA. Results of analysis for 1998 indicated that of the effluent samples evaluated for faecal coliform (n=57), 25/57 (38.6 percent) were satisfactory and 61.4 percent were unsatisfactory, using the NCRA standard of 1000 mpn/100mls. When compared to the effluent standard for BOD (20mg/l), the results showed that 38/68 or 59.9 percent of the individual readings were satisfactory and 30/68 or 44.1 percent unsatisfactory.(Au)