Twice a year, we clean a 15-mile portion of the Contra Costa Canal with a giant radio-controlled sled.
Pushed by the current in the canal, the sled acts like a giant squeegee, pushing mud and grim ahead of it. At gates or drops, the sled is lifted out of the canal, and then placed back on the other side. A day later, the accumulated mud and grime is scooped out of the canal.
The sled's speed is controlled by lifting or lowering the huge blade. There are also adjustable flaps on its sides.
The sled cleans the canal from Antioch to Clyde (see map). Downstream of Clyde, the District is able to drain the canal in the winter and clean the canal.