The dredger winches itself backwards and forwards along a cable strung across the lake, dredging in both directions.
A driven helical cutter feeds dredgings to the powerful suction pump which discharges then through a floating pipeline to a disposal area. This can be as far as 2,000 metres from the dredging operation.
The dredged material is allowed to settle out and the cleared water is then returned to the river or lake system. This residue is either removed, or left to reclaim the area for nature conservation or other purposes.
Sometimes, on private estates for example, only small lakes or pools require clearing. For these a simplified easily transportable suction system is used in place of the MudCatTM dredger. (Mud Cat is a registered trademark of Ellicott international, see www.dredge.com and www.mudcat.com)
The discharge pipe is suspended from floats in the water and continued overland by the most suitable route, surmounting obstacles where necessary.......
.......to the point of discharge at the disposal area.
The dredgings settle out, permitting the cleared water to be returned to the lake system.
20th century techniques and equipment help to restore and preserve the beauty of moats often used in the middle ages to protect livestock from the dangers of night marauders