Wastewater Treatment In Kathmandu: Management, Treatment And Alternative : Bacherlor's thesis Enviromental Engineering

Abstract

Main aim of this thesis was to understand the wastewater situation in Kathmandu, Nepal and its impact in natural water stream, how it is managed and treated. After understanding the scenario of wastewater treatment in Kathmandu, a suitable alternative wastewater treatment system is recommended for future use. Technical as well as managerial problem exists in Kathmandu, thus from my experience in Mikkeli, Finland I came up with the model that is handled by the municipality itself because skill and managerial problem to protect the city can be found in municipal level only. New models are always interesting for people, thus increasing efficiency along with interest. Bagmati River, partially operating activated sludge Guheshwori wastewater treatment plant and low energy using system to treat wastewater known as constructed wetland wastewater treatment system was studied in detail. Artificial wetland is constructed to treat wastewater through natural method as it happens in natural wetlands. Though this system has huge potential in a country where energy scarcity exists but technical and managerial problem and lack of awareness hampered the success of this system too. Analysis of physical, chemical and biological parameters that indicate the characteristics of wastewater was done by collecting samples and by reviewing secondary data. Result showed that Kathmandu is in need of development in wastewater management and treatment because the situation has degraded dramatically in the past decade. Therefore, a new method sequencing batch reactor was recommended. It follows the same method as activated sludge but all the treatment processes happens in the same basin. This system proved to be more viable for Kathmandu because it uses less space, energy and money compared to continuous flow system. Compared to constructed wetland wastewater system also this system has high lifespan and can treat large amount of wastewater in less space. Comparison of this system and current status of existing wastewater treatment plants in Kathmandu demands implementation of this new and attractive model.