Peter wrote: I recently moved into a new house, and the builder put in a drainage swale at the bottom of my backyard. Since I am at the end of my street, whenever it rains I get all the runoff through my backyard to the street. The drainage swale runs across my back fence as you can see in the pictures. I would like to put in a path of some kind across the back fence, but don't know how to maintain the drainage. I'm thinking of a PVC pipe covered with gravel. Any Suggestions?.
I would dig down a bit and put in a plastic sheet, like a pool liner, much like you have in the photo. Then several inches of clean 3/4 inch gravel, the stuff they use to put around the drainage tiles at the foot of the foundation. Then a geotextile filter cloth and then topsoil. Right at the both ends of your property do not use any top soil but bring the gravel, and perhaps decorative rocks, right up to the surface. This will give the "underground diversion ditch" a way in and out. If you want to put a pipe into all of this ok, but more water will probably go around the pipe than through it. Since water always follows the path of least resistance, the idea is to create a clear flow under your grass that can get both in and out.
Another way I deal with serious run-off is to make it decorative with stones and patio blocks on a deep gravel bed to look like the Japanese garden idea, but in fact it is a diversion ditch. No top soil sometimes makes it all easier. Follow this link for more information on water runoff control.