Introduction
1.1 Background Information
Access to clean and affordable water is important for human health, economic productivity, and environmental sustainability. Watershed management is paramount for all communities, especially those utilizing a surface water source for consumption. However, most surface water quality is well below minimum standards for human consumption especially during rainy seasons which increase surface erosion and runoff.
It is estimated that one billion people lack access to improved water sources as defined by the UN (WHO, 2000). This figure does not include another estimated 1 billion people with access to improved water sources (water transported in a pipe network) that are not directly treated. By these estimates, there are two billion people without access to safe drinking water. Thus, there is a need for a cost-effective solution to provide safe drinking water for a large proportion of the world's population currently lacking safe drinking water. AguaClara is a unique project in the School of Civil and Environmental Engineering at Cornell University that utilizes design, laboratory and field research, as well as extensive community outreach and working partnerships to provide cost-effective community-scale water treatment plants for the Global South. Of the 2 billion people without access to clean drinking water, a quarter could utilize turbid surface waters. A quarter of those utilizing untreated surface waters are estimated to live in communities between 1000 and 50,000 people. Thus, an estimated 125 million people could be potentially served by AguaClara technology. AguaClara water treatment plants utilize a gravity-driven treatment process train of rapid mix, flocculation, sedimentation, and disinfection.
This thesis presents the evaluation and optimization of effluent performance in an upflow sedimentation tank with floc blanket and lamellar sedimentation. Optimization of effluent performance in this system is crucial for achieving low turbidity water for disinfection to be effective.