catchwork

from The Century Dictionary.

• noun An artificial watercourse or series of watercourses for irrigating such lands as lie on the declivities of hills; a catch-drain. Also called catchwater.
• noun Any mechanical appliance used to arrest motion by means of ratchets, pawls, dogs, and friction gripping-surfaces.

from the GNU version of the Collaborative International Dictionary of English.

• noun A work or artificial water-course for throwing water on lands that lie on the slopes of hills; a catchdrain.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A simple irrigation system, used on sloping land, in which water from a stream or spring is fed in at the top and allowed to trickle down over a number of artificial terraces.