Signature Projects

This project encompasses the turnkey design, manufacturing, and installation of hydraulic mechanical, electrical, instrumentation & control, and monitoring systems for the Nanhua Reservoir Sediment Bypass Tunnel, covering the emergency/maintenance gates (fixed-wheel vertical lift gates) and control gates (radial gates) that form the tunnel's safety gate system. The control gates feature the deepest design head of any radial gate in Taiwan at 60 metres, demonstrating advanced technical capability in the design and manufacture of large-scale, deep-head gate structures. (Note: The overall Nanhua Reservoir Sediment Bypass Tunnel project also encompasses tunnel excavation, intake cofferdam construction, and civil works, which are carried out by RSEA Engineering. Nan Dao Engineering's scope is focused on the planning, design, manufacturing, and installation of the hydraulic mechanical, electrical, and monitoring systems.)

Nanhua Reservoir is a critical water supply facility serving the Tainan region. Due to progressive siltation, its effective storage capacity has been reduced to 62% of the original design capacity. As the reservoir previously lacked bottom-level sediment discharge facilities, flood releases could only be managed through the spillway — resulting in an unfavourable operating condition in which turbid inflow was stored while clear water was discharged, gradually undermining the reservoir's storage and flood control functions. To address this, a sediment bypass tunnel was planned to enable the timely discharge of density currents and turbid water through the tunnel to the downstream river channel, transitioning the operating mode to one in which clear water is retained and turbid water is discharged. This approach slows the rate of siltation, extends the operational lifespan of the reservoir, and ensures stable water supply and sustainable water resource management for southern Taiwan. The gate systems delivered by Nan Dao Engineering are indispensable to the safe operation of this sediment bypass tunnel.