upper water level for flood control

例句：

1. 1.The upper water level is critical for flood control.
   上水位对于防洪至关重要。
2. 2. The engineers are working on raising the upper water level to prevent flooding.
   工程师们正在努力提高上水位以防止洪水。
3. 3. The city has implemented a system to monitor the upper water level for early warnings.
   该市实施了监测上水位的系统以进行早期预警。