Testimonial by customer "I used the product to dry out some very soggy lawn areas, and the results have been nothing short of spectacular. We live on a plateau in Western Washington that is the remnant of a 30,000 year old glacier, so the soil is extremely hard and full of rocks (it's actually called "glacial till" because of this). The soil is mostly clay and the rocks are the size of softballs, so nothing drains past whatever topsoil is brought in. My back yard couldn't be used for almost 6 months out of the year, and my front yard couldn't grow grass because it was so wet.
I dug 42" deep main trenches for the collector pipe and 18" deep trenches for the Smartdrain belting. I encased the belt with sand and then covered the entire yard with 8" of golf course mix (20% sand, 20% loam, 60% topsoil). The collector pipes drained into underground drywells filled with tons of excavated rock. My neighbors all thought I was nuts when I put it in (except for the civil engineer next door -- he understood the technology completely), but they are all converts now. Many had previously spent thousands and had the typical French drain systems put in several years ago and they either don't work very well or don't work at all today. My yard is now the envy of the entire neighborhood."
Kevin D. Sammamish, WA 2010