A White Wagtail (Motacilla alba, 白鹡鸰). We have had steady rain for a couple weeks and expect rain for a few weeks more, but yesterday morning we were inundated with heavy downpour, drastically flooding parts of the city.
This is the season for heavy rain in this part of the world. 100 years ago in 1924, Changsha also experienced severe flooding; I cannot find much about what parts of the city were then affected but there are some (sadly low resolution) photos available from the University of Bristol's online Historical Photographs of China collections.
Image courtesy of George Trobridge Collection, University of Bristol Library (www.hpcbristol.net). C. July 1924.