000			03719nam a2200385 4500
005			20260818114052.0
008			210598 th eng
035			_a.b10285659
099		9	_aAIT Thesis no.WA-86-16
100	0		_aKhanate Sakulyong
245	1	0	_aFlood study of Nam Pong river at Pong Neeb gorge
260			_aBangkok : _bAsian Institute of Technology, _c1986
300			_a53 p.
490	1		_aThesis ; _vno. WA-86-16
500			_aA thesis submitted in partial fulfilment of the requirements for the degree of Master of Engineering, School of Engineering and Technology
502			_aThesis (M.Eng.) - Asian Institute of Technology, 1986
520			_aThe main objective of this study was to verify to what extent heavy deforestation within Nam Pong river basin during the recent decades or retention of the Pong Neeb gorge explains the changes in the observed floods of the basin. The deforestation effect was detected by statistical analysis on annual maximum runoff data from Yorn, Nan and Pasak river basins, where extensive forest destruction has taken place. Results of the study show, that the three basins have no any significant systematic changes on the flood peaks. This indicates that for big basins with gradual deforestation over a number of years the long-tenn effect of deforestation on the flood peaks is so small that it has no practical impact, particularly when compared to the natural climatic variations. The mathematical m:xlel, a combination of hydrological storage routing and hydrodynamic river routing, was developed to simulate the flood flows of Nam Pong river including the retention storage upstream of the gorge in pre-dam period and to verify the effect of the retention on flood peaks. The hydrological storage routing was based on the continuity equation for a single reservoir. The hydrodynamic river routing consists of the unsteady free surface flow equations which were solved numerically by using the finite difference approximation of the implicit scheme. The various flood inf low hydrographs to Ubol Ratana reservoir were used as the input of the combined m:xlel. Results of this simulation show, that the peak discharges downstream of the gorge were reduced considerably by the effect of the retention storage. The peaks were reduced by 35% upto 63% for a 2-yr flood and a 10,000-yr flood respectively. The Manning's roughness coefficient was also considered to be a factor affecting the flood flow in the river channel downstream of t he gorge. However, the changes of flood flow influenced by the value of Manning's roughness coefficient was insignificant compared to the peak reductions affected by the retention storage of the gorge.
650		0	_aFloods _xNam Pong River
700	1		_aNielsen, Steen Asger, _eChairperson
700	0		_aTawatchai Tingsanchali, _eExamination Committee
700	1		_aBogardi, Janos J., _eExamination Committee
710	2		_aThe Australian Government, _eScholarship Donor
810	2		_aAsian Institute of Technology. _tThesis ; _vno. WA-86-16
856			_3Full-Text _uhttp://203.159.5.9/ait-thesis/detail.php?q=B19792
907			_a.b10285659 _bmnait _cs
902			_a240401
998			_b2 _c951012 _dm _ea _fs _g0
945			_lmnait
945			_lmnarc
942			_c22
942			_c40
909			_aBarcode : 30050120573539 _bCREATED : 2014-02-04 _cRECORD # : i12785453 _dLPATRON : 0 _eLCHKIN : - _f# RENEWALS : 0 _g# OVERDUE : 0 _hIUSE3 : 0 _iTOT CHKOUT : 0 _jTOT RENEW : 0
909			_aBarcode : 30050160034921 _bCREATED : 2016-09-02 _cRECORD # : i12879083 _dLPATRON : 0 _eLCHKIN : - _f# RENEWALS : 0 _g# OVERDUE : 0 _hIUSE3 : 0 _iTOT CHKOUT : 0 _jTOT RENEW : 0
999			_c45654 _d45654