On August 21, the national development and reform commission (NDRC) issued an official reply on the construction plan of the fourth phase of Chengdu urban rail transit (2019-2024).In principle, it agrees with the construction plan of the fourth phase of Chengdu urban rail transit (attached), including the construction of the 2^nd phase of line 8, the 3^rd  phase of line 10, the 1^st phase of line 13, the 2^nd phase of line 17, the 3^rd phase of line 18, the 2^nd phase of line 19, the 1^st phase of line 27, and the 1^st phase of line 30. The planning period is 2019-2024.