On October 10 of the same year, the Tianjin Underground Railway was opened to traffic. In 1981, Miyun Reservoir was built on the upper reaches of the Hai River and is used to supply water for Beijing, however the reservoir stopped the river from supplying water to Tianjin, resulting in difficulty in the use of water in Tianjin. In the same year, the State Council of the People's Republic of China decided to initiate a project to solve the problem of water use in Tianjin and attract talented individuals to the city's academic centers.