Urban drainage and water quality modeling at Pattaya beach | |
| Author | Bui Thi Khanh Chi |
| Call Number | AIT Thesis no.WM-03-15 |
| Subject(s) | Water quality--Thailand--Pattaya Drainage--Thailand--Pattaya |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science |
| Publisher | Asian Institute of Technology |
| Abstract | The purpose of this research is to develop integrated modeling for evaluating bathing quality condition at Pattaya beach. The study is based on modeling of the impact of the wastewater and stormwater emissions from Pattaya city on the water quality in the sea. One of the indicators of pollution, the total coliform bacteria, is chosen for modeling at Pattaya. This integrated modeling consists of two modelings which are linked together. The dynamic pollution transport is simulated by using of a deterministic transport model for urban drainage networks- Mouse and Mouse Trap. The water quality together with tidal forcing is conducted by Mike 21. Field work is carried out to measure rainfall, water level and bacteria concentration during October 2003. The data receiving and transmission system was tested by transferring hydrological real time data every 5 minute from Pattaya to server at AIT. From the result of data analysis, it shows that approximately 92% of data bulk is successfully transferred in real time by using Internet. Mouse and Mouse Trap model is calibrated and verified to quantify appropriate set of model parameters for this specific area. Calibration for Mouse model reveals good agreement between model calculation and observed data. Sensitivity analysis is conducted and manifested in the fact that impervious area, time concentration and Manning's number are the most effective parameters at station 1. Meanwhile, impervious area contributes significant sensitivity at station 2 in Mouse model. For Mouse Trap, it shows that only advection-dispersion decay parameter plays an important role in calibration. Storm handling capacity of sewer system is tested with 5-year return period rainfall. The result shows that some flooding locations occur about 5 to 60 cm with 1.2 km during 15 to 70 minute at Pattaya First Road. Result of hydrodynamic calibration in Mike 21 shows good agreement between calculated and observed current. Result of bathing water quality in Pattaya bay shows that the negative impact of seawater pollution has been reduced after the WWTP was built and tidal forcing plays role in dispersion and spreading pollution. Nevertheless, bacteria concentration along the seashore is still greater than standard from 5 to 16 times in dry day and from 9 to 50 times of standard in rainy day. It is also indicated that the effected area and contaminated length of seashore in spring tide is greater than those in neap tide. High fluctuation of water level and current contribute to spreading and increasing unsafe area for swimming. These areas in dry day are approximately 1.7 km2 with 1.7 km of seashore length in neap tide and 2.4 km2 with 3.5 km of length during spring tide. |
| Year | 2004 |
| 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 Singh ;Sutat Weesakul |
| Examination Committee(s) | Mark, Ole ;Gupta, Ashim Das |
| Scholarship Donor(s) | Government of the Netherlands |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2004 |