An estimated 80% of wastewater is discharged into the environment without treatment (UN), threatening aquatic wildlife, quality of groundwater and surface water resources, and human health. To avoid these negative effects, it is important to improve wastewater collection and treatment from both households and industries.

Cities can help achieve this goal by improving wastewater transport and treatment infrastructure, adopting laws and regulations for wastewater treatment discharge, and offer financial incentives for businesses and industries to improve pollution controls over their effluents and advance treatment technologies.