China Pinglu Canal Mangrove Protection Project

The Pinglu Canal is a strategic infrastructure project in China and the first major river-sea canal constructed since the founding of the People's Republic of China. The canal, stretching 134.2 kilometers, begins at the Pingtangjiangkou in Hengzhou, Nanning and ends at Qinzhou Port. Built to Class I inland waterway standards and accommodating vessels up to 5,000 tonnes, it required nearly 400 million cubic meters of excavated earth and rock. Section HD15, located at the southernmost section of the canal's estuary, stretches approximately 22 kilometers. Construction primarily involves dredging, reef blasting and bank protection. Due to the sensitive ecological environment in the area, particularly near the mangroves and estuarine ecosystems at the estuary, environmentally friendly construction was highly demanding.

To reduce the turbidity and suspended matter caused by dredging operations in the canal, which can lead to the suffocation of mangroves, this project employs a multi-layered anti-fouling curtain deployment strategy. This includes semi-enclosed curtains, 1.5–2.5 meters deep, deployed around the dredgers and fully enclosed curtains at the outfall and mangrove areas. Key features include a 20-meter monolithic permeable round-filament filter fabric, buoys and weighted sandbags. The design is optimized for tidal patterns and a maximum flow velocity of 0.79 m/s.

HOKBG provides design and customization services for anti-fouling curtains, including a 20-meter integrated round-filament permeable filter cloth, buoys, weighted sandbags, anchoring systems, reflective strips and connection accessories. HOKBG also provides on-site guidance for installation, curtain transfer and technical support for deployment plans and environmental standards. A total of 20,000m of water-permeable anti-fouling curtain was used.

Water quality outside the anti-fouling curtain met functional zone standards. The dispersion range of suspended solids was reduced from 197.5 meters to below 39.5 meters, achieving a control efficiency exceeding 80%. No turbid water intrusion was observed in the mangrove area. This deployment method ensured both flexible construction and environmental protection.