That's the problem with living in an autocratic system with no property rights, no need for the government to justify taking your land. In fact, 150,000 is actually a pretty small number compared to the 1.4 million evicted for the Three Gorges Dam, the 1.5 million they evicted from Beijing alone for the 2008 olympics or tens of thousands in 2017 to clear profitable land for local developers (almost 1/2 the budget of local governments come from land sales).
The idea that the government would be willing to move another 150,000 in a rural area for a major propaganda boon seems to be the most likely option in my mind.