| Author | Budhathoki, Nisha |
| Call Number | AIT Thesis no.WM-05-14 |
| Subject(s) | Watershed management Nepal Baghmati River Basin
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of
Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | Environmental issues such as soil erosion and land degradation, and water quality deterioration due to population growth, urbanization and industrialization are main challenges to improve water resources protection and management. To address these issues and problems, a basin-wide approach is essential for regulating pollution originating from point and diverse sources. Watershed scale water quality models are being widely used in assessing the environmental conditions and developing mitigation measures to combat point and non-point source pollution (NPS) in a watershed. The objectives of this research are to apply a watershed scale model to predict sediment and pollutant loads in the Bagmati River Basin in Nepal and to investigate several alternative management practices to control pollution from point and non-point sources. The Soil and Water Assessment Tool (SWAT) model used in the study requires data and information on climate, topography, soil and land use, cropping pattern, water use, and wastewater quality. The model is calibrated and validated for flow, sediment and selected water quality parameters - Nitrates (NO3), Total Phosphorus (TP) and Dissolved Oxygen (DO) using the observed data at Khokana and Paneradovan. The flow predictions are satisfactory for both calibration and validation whereas sediment predictions are at acceptable level. The results indicate inability of SWAT to accurately simulate the extreme single events. The model performance in simulating TP and DO is satisfactory, but NO3 could not be simulated well by the model. Agriculture is found to be the major contributor of pollution, generating highest sediment and nutrient loads. Point sources are also contributing to a significant amount of Phosphorus and Nitrogen. The model is applied to simulate sediment, NO3 and TP loads under different management scenarios - Conservation tillage (non-point source control) and effluent discharge limit for TP and NH3-N (point source control). The results suggest that combination of point and non point source controls are required to attain pollution reductions in the Bagmati Watershed. SWAT model is found to be a promising tool to predict sediment and pollutant loads in the Bagmati Watershed. The model could provide critical areas requiring immediate focus for remediation measures, and could serve as a rational decision-making tool for watershed planning and management to evaluate the impact of alternative land management practices and effluent loadings to the river water quality |
| Year | 2006 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Babel, Mukand S. ;Gupta, Ashim Das |
| Examination Committee(s) | Clemente, Roberto S.;Tawatchai Tingsanchali;Aramaki, Toshiya |
| Scholarship Donor(s) | AITAA and AIT Fellowship |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2006 |