Identification of trend and probability distribution for time series of annual peak flow in Tapi Basin, India

Abstract

This study deals with trend analysis of observed annual peak flow time series data at four stream gauging stations in the Tapi Basin. Innovative trend analysis, recently proposed by Şen, and Mann Kendall test are used to ascertain the trend in extreme annual flow (flood) at aforesaid gauging stations in the Tapi Basin. Also, the time series of extreme flow data have been checked for their serial correlation and, subsequently, flood frequency analysis is undertaken to obtain floods of different return periods. The fitted probability distributions are also used to predict extreme flow into the Ukai Reservoir on the basis of information from upstream gauging stations. The methodology has also been used to predict runoff into the reservoir from the unguaged catchments.

Keywords:

• annual peak flows
• innovative trend analysis
• serial correlation
• flood frequency analysis
• return period
• ungauged catchment
• Tapi Basin

Acknowledgement

Authors are thankful to the All India Council for Technical Education (AICTE), New Delhi, for providing financial support to collect the data for the present study under the Nationally Co-ordinated Project (NCP) on ‘Development of Water Resources and Flood Management Centre at SVNIT–Surat’. The authors are also grateful to the Central Water Commission, Government of India, for providing data under the said scheme. Additionally, the authors are also grateful to Shri K.B. Rabadia, Superintending Engineer, Surat Irrigation Circle, Narmada Water Resources, Water supply and Kalpsar Department, Govt. of Gujarat for providing data under said scheme.