Port Mann Main Water Supply Tunnel –
Ground Freezing the TBM face under the Fraser River
During tunnel mining operations under the Fraser River in Vancouver, the Tunnel Boring Machine (TBM) was damaged and required immediate repair. Liquid nitrogen was used to freeze the soil at the cutter head so that repairs could be completed. Refrigeration pipe drilling and freezing operations were completed from a platform near the middle of the river. Liquid nitrogen was transported from the shore with barges that were being refilled by tanker trucks.