What is another word for a roadside trench used drainage?

General terms:

* Drainage ditch: This is the most common and straightforward term.

* Roadside ditch: This emphasizes the location.

* Swale: A shallow, grassy channel designed to collect and convey stormwater.

* Gutter: A channel along the edge of a road, often paved, for collecting stormwater.

* Culvert: A pipe or structure that allows water to flow under a road.

More technical terms:

* Stormwater management system: This is a broader term that refers to any system designed to manage stormwater runoff, which could include roadside ditches.

* French drain: A type of drainage system that uses gravel and perforated pipe to collect and redirect water.

* Subsurface drainage system: This refers to any drainage system that is installed below ground level, which could include roadside ditches.

The best word to use will depend on the specific context and the level of formality you need.