ADS 18410020 18" x 20' Single Wall Perforated Highway Pipe. The Single Wall corrugated HDPE pipe is ideal for drainage projects where flexibility, light weight and low cost are important. Homeowners find that this corrugated pipe is an economical, easy–to–install solution to common residential storm water drainage problems. These may include downspouts run off, foundation and window well drains, driveway culverts and wet spots on the lawn.