With China’s rapid progress in marine engineering, a breakthrough has recently attracted widespread attention—the launch of two ultra-large trailing suction hopper dredgers (TSHDs).
The domestically developed vessels Tongjun and Junguang have officially entered service, marking a new milestone in China’s dredging capabilities.
Even Western experts admit: “China’s infrastructure power is frightening—two more giant dredgers have just been launched!”
This raises a critical question: could these technological marvels help solve the long-standing problem of silt accumulation in the lower Yellow River, where “suspended river” conditions pose major flood risks?
Ultra-Large Trailing Suction Hopper Dredgers
The launch of Tongjun and Junguang represents a leap forward in dredging technology.
Compared to traditional dredgers, these new vessels offer significant advantages:
- Size and Capacity: Each vessel measures 198 meters long and 38.5 meters wide, with a maximum dredging depth of 120 meters—roughly the height of a 40-story building.
- Hopper Volume: Each can hold up to 35,000 cubic meters of silt, equivalent to 18 Olympic swimming pools.
- Efficiency: Their hoppers can be filled in just 90 minutes, far outpacing conventional dredgers.
Unlike cutter suction dredgers, which grind through seabed rock with rotating cutters, trailing suction hopper dredgers loosen silt with high-pressure water and suction it into onboard hoppers, then sail to deposit the material elsewhere.
This makes them particularly suited for large-scale land reclamation, deep-water dredging, and channel maintenance.
The Yellow River “Suspended River” Problem
The lower Yellow River has long faced the unique challenge of being a “suspended river,” where the riverbed lies above surrounding land due to centuries of silt accumulation.
In some parts of Henan province, the riverbed is 23 meters higher than nearby ground, creating severe flood risks. The river’s mouth widens to 1,500 meters, where silt buildup further complicates the situation.
Roughly 300 kilometers of the lower Yellow River are suspended, threatening agriculture, industry, and the safety of millions along its banks. Heavy rains can quickly raise water levels, overwhelming levees and triggering disastrous floods.
But direct dredging poses risks: destabilizing the riverbed, altering flow patterns, or even causing breaches.
Can Dredgers Solve the Problem?
Using Tongjun and Junguang alone cannot fully resolve the issue. The scale of silt is enormous: the Henan section alone holds an estimated 3.072 billion cubic meters of silt.
Even with a 35,000 m³ hopper, over 87,000 full dredging cycles would be needed—requiring at least 15 years of continuous operation under ideal conditions. In reality, weather, maintenance, and transport delays would stretch this timeline even further.
Moreover, the lower Yellow River’s complex hydrology—where main channels and inner levees form “double suspended rivers”—means careless dredging could destabilize the riverbed, worsening flood risks.
Toward a Comprehensive Solution
Experts argue that the Yellow River’s silt challenge requires a scientific, phased approach rather than brute-force dredging. Recommended measures include:
- Phased dredging to gradually reshape the riverbed without destabilizing flows.
- Levee reinforcement to protect against sudden floods.
- Tributary dredging to improve water distribution.
- Soil and water conservation upstream to reduce silt inflow.
Only through integrated management—balancing dredging, ecological protection, and flood prevention—can the suspended river threat be sustainably managed.
Conclusion
The launch of Tongjun and Junguang is a landmark achievement in China’s dredging technology. These vessels not only strengthen the country’s marine engineering capabilities but also provide new tools for addressing the Yellow River’s pressing challenges.
Yet, advanced technology alone cannot solve the problem. Only through comprehensive planning, cautious implementation, and ecological balance can China achieve both effective silt management and long-term river safety.
As challenges continue, innovation combined with sustainability will remain the guiding principle for China’s water engineering future.
References:
- China Communications Construction Group technical reports
- Ministry of Water Resources, Yellow River management data
- International dredging industry publications
