dredge

to remove unwanted things from the bottom of a river, canal, lake, etc. using a sucking or other device ขุดลอก

When the water is pushed by the propellers, it helps dredge the canal bed, sweeping out rubbish and clay.

The Irrigation Department should dredge and improve the networks of existing waterways and canals in the central region.

A project to dredge a huge canal parallel to the river – called the Chao Phraya II, in order to hasten the flow of runoff water into the Gulf of Thailand and keep the Central Plains from inundation – was proposed many years ago but has been implemented