Author(s): C. C. Lamparelli; D. O. Moura; K. C. Pinto; A. C. Camolez
Linked Author(s):
Keywords: Sea outfalls; Coastal water quality; São Paulo coast; Sea outfall monitoring
Abstract: Most of Brazilian State capitals are located in the coastal zone. In those metropolitan regions where population and tourism have grown significantly in the last years, ocean disposal is an appealing solution for sanitation systems. Although São Paulo State in the southeastern region represents only 10% of the Atlantic coastline extension, it is the most populated and has the majority of the Brazilian sea outfalls. There are currently eight wastewater sea outfalls in operation. All of them have on ly preliminary treatment followed by disinfection through chlorination before releasing the effluent into the sea. The first one was constructed in Santos and began to operate in 1979. Since then commissioning protocols have been modified and have improved based on the knowledge acquired with the monitoring programs. The more recent one serves the County of Ilhabela and started to operate in 2010. CETESB as the Environmental Agency of the State of São Paulo is responsible for outfalls licensing process and permits issuances, evaluating the adequacy of the waste water plants projects, defining environmental monitoring programs and performing the regulation and enforcement of water quality compliance. Environmental monitoring of sea outfalls is carried out by CETESB and is a requirement for their commissioning. CETESB’s sea outfall environmental monitoring started in 2002 in two of the existing outfalls. The main objective of this monitoring program is to identify possible impacts of those discharges in the marine environment. During the first years sampling methodologies were tested in order to establish a monitoring design. The data gathered in these surveys showed that most of marine environment alterations were related to sediments, including accumulation of organic matter and nutrients. In some cases, water quality was also impaired. Alterations such as nutrient enrichment were observed more often in Santos bay. Despite their importance, it is worth mentioning that marine environment monitoring surveys are complex and expensive. One must also consider that in developing countries there is a lack of environmental data records, and in most cases there is practically no previous information about the studied area. Environmental Monitoring conclusions were useful to identify the major alterations in marine environment and to address which improvements and adjustments would be necessary in each outfall to reduce or to prevent future environmental impacts in water and sediment quality.
Year: 2016