Aqueduct
From Eco - English Wiki
Aqueducts are built by using a special type of Brick.
Aqueducts must be built in a V-Shape and will then allow water to flow over vast distances, instead of the default 8 Blocks water flows if surrounded by any other material.
The aqueduct was bugged, causing them to be ineffective, as of v. 0.8. However, they appear to be working in 0.9.
When carrying Bricks and selecting the Hammer-Tool, you can find the Aqueduct-Blocks in the Selection shown as three green Bricks.