Abstract:
While most of industries in Industrial Zones are connected to the centralized wastewater treatment plants, a large number of scattered industries and business facilities are served by on-site (decentralized) wastewater treatment systems (OWTSs) in Sri Lanka. Despite the many benefits, OWTSs may also pose challenges when it becomes operational in the long run. Many operative OWTSs today face difficulties to meet the discharge wastewater quality requirement of National Environmental Standards mostly due to lack of appropriate systems, limited understanding of treatment processes, insufficient process monitoring and maintenance activities. Therefore, adverse impacts could result on public health trough pathogenic contaminations and ecosystems of receiving water bodies due to nutrient pollution. On the other hand, insufficient monitoring and maintenance include the inability of OWTSs to perform as expected and reduce their lifespan. Therefore, it is very important to take proactive interventions for its proper monitoring and maintenance. This paper highlights the quality of treated wastewater from operative OWTSs, public health and environmental concerns related to the operative OWTSs and other aspects of proper monitoring and maintenance of OWTSs.