Submarine outfalls a viable alternative for sewage discharge of coastal cities in Latin America and the Caribbean

Abstract

[Abstract] An overview of present sewage disposal practices in Latin America and the Caribbean is given. After reuse, the long submarine outfall alternative with pretreatment (milli-screens) or primary treatment is a more attractive disposal method relative to secondary treatment with near shore disposal in terms of reliability, efficiency, cost and low operational and maintenance requirements. However, sewage discharges near sensitive natural biological communities, such as coral reefs, should be avoided. Cost curves for submarine outfalls are presented. The availability of modern plastics and construction methods also make long submarine outfalls feasible for small communities and tourist centers. Technical details of the present 104 outfalls in Latin America and the Caribbean are presented. Their distribution is as follows: Argentina (1), Bermuda (1), Brasil (12), Chile (18), Colombia (2), Costa Rica (1), Ecuador (1), Martinique (1), Mexico (9), Peru (2), Puerto Rico (15), Uruguay (1) and Venezuela (39). A brief performance summary of the submarine outfall at Ipanema servicing part of the city of Rio de Janeiro, Brazil is also presented.