On February 25, the construction site of the westward water-diversion tunnel of the Oujiang River Water Diversion Project echoed with the rumbling of machinery, as "Fenjin" (Striver), the first 6.5m-class TBM in Zhejiang Province's water conservancy system, worked at full capacity, boring through the mountains and determined to "chew through" the most perilous section of the tunnel.

The double-shield TBM "Fenjin" is a 150-meter-long hard-rock boring machine. In tunnel excavation, its unique double-shield design enables it to overcome extremely hard strata along the construction route and reduce the impact on existing tunnels. In the Oujiang River Water Diversion Project, only the westward water-diversion tunnel uses this "diamond drill," because although this tunnel is only 3,429 meters long, it is the section with the most complex terrain and the greatest construction difficulty in the entire project.

According to reports, the route of the westward water-diversion tunnel passes beneath existing structures including the Zhaoshandu water-diversion tunnel, the No. 1 and No. 2 tunnels of the Wenzhou Ring Expressway, the No. 1 and No. 2 tunnels of Fuzhou Road, and the Yuanyanzhai tunnel of the Hangzhou-Shenzhen Railway. It can be said that for every meter advanced, the construction workers proceed with extreme caution, because the slightest carelessness could lead to unimaginable consequences.

It is understood that the Oujiang River Water Diversion Project is the "dual lifeline" of Wenzhou's urban water supply, undertaking the important functions of emergency standby water supply for the city, ecological water replenishment of the river network, irrigation, and flood control and drainage. It is also currently Wenzhou's water-diversion project with the largest diversion flow, the longest water-conveyance tunnel, the largest investment scale, and the most simultaneous work faces. The total length of the project's water-conveyance route is about 81 kilometers, consisting mainly of newly built tunnels. Once put into operation, the average annual total water diversion volume can reach 743 million cubic meters, benefiting 4.2 million people in Wenzhou and meeting the city's medium- and long-term water demand for development.