How did Tanggu’s salt fields expand between 1969 and 1974?

Between 1969 and 1974, the salt fields in Tanggu underwent significant expansion and modernization. The project involved two primary efforts:

• Infrastructure Improvement: Workers straightened the sides and leveled the bottoms of approximately 10,600 acres (4,300 hectares) of channels, shallow ponds, and crystallizing pans.1
• Land Reclamation: An additional 4,450 acres (1,800 hectares) of land were reclaimed from the Bo Hai.1

These improvements were part of a broader effort to increase the production capacity of the fields, which remain a vital source of salt for China’s food and industrial sectors.1