Drainage service
Swale Installation
Shallow grassed channels that move surface water across a property along a controlled route, without pipe.
Overview
Swale Installation in southeastern Pennsylvania
Where there is enough width and fall, a swale moves large volumes of surface water with no pipe to silt up, no outlet to block and no components to fail.
It is a good answer for runoff arriving across open ground, and a poor one where there is no room for the channel or no fall for it to follow.
System components
Shaped channel / Stabilised base / Turf or stone lining
What makes a swale work
Consistent fall along its length, adequate cross-section for the flow it has to carry, and a stabilised surface — turf where velocities are low, stone where they are not. A swale cut without stabilisation erodes into a gully at the first significant storm and becomes a maintenance problem instead of a solution.
It also has to go somewhere. A swale that carries water competently to a point with no outfall has moved the problem rather than solved it.
Where a swale beats a pipe
For large surface volumes across open ground, a swale has more capacity than a residential pipe run and needs less maintenance. It handles debris that would block an inlet, and it is far cheaper to inspect.
It is the wrong choice where the route crosses a driveway or lawn area that has to stay usable, where there is insufficient width, or where the property has too little fall to establish a working channel.
Questions
Swale Installation questions
Is a swale just a ditch?
A swale is shaped, graded to consistent fall and stabilised so it does not erode. An unstabilised cut of the same shape becomes a gully in the first heavy storm. The shaping and the surface are what distinguish them.
Can I mow a grassed swale?
Yes — a turf swale is maintained as lawn, which is part of its appeal. Stone-lined sections used where velocities are higher are not mowed, and are usually placed only where they are needed rather than along the whole run.
Will a swale handle water coming from a neighbouring property?
It can, if it is sized for that contributing area rather than for the lot alone. Establishing how much water is actually arriving is part of the design, and it is the step most often skipped on properties that receive upslope runoff.
By town
Swales by town
Each page covers how this system behaves on that town's ground.
Need swales?
On-site assessment. Free written estimate. No obligation.