Under the joint action of climate–human activities the use of runoff data whose mathematical properties have changed has become the key to watershed management. To determine whether the data have been changed, the number and the location of changes, we proposed a change-point detection framework. The problem of determining the parameters of wavelet transform has been solved by comparing the accuracy of identifying change points. This study helps traditional models adapt to environmental changes.

With the aggravation of the global climate change，using reasonable methods to study changes in precipitation is very important for planning and management of water resources. Based on the time series of precipitation in Beijing from 1951 to 2015, the multi-scale features of precipitation are analyzed by the Extreme-point Symmetric Mode Decomposition (ESMD) method. The results show that the precipitation series have periodic changes of 2.6 years, 4.3 years, 14 years and 21.7 years.

The time-varying design flood is a dynamic design flood, which considers the shortage of water resources and followed the law of flood evolution in reservoir operation. Compared with the traditional design flood, time-varying design flood can make full use of the measured data, reflect the actual situation of the reservoir and so on. Using time-varying design flood to develop a reservoir operation plan not only ensures reservoir safety but also effectively improves water resource utilization.