So here is the problem: About five years ago (on an account I have had for the last year), the previous LCO built 3 tiers of large stone retaining walls. He then back filled them with fill. They look pretty good and have not moved, but because he only used very large rocks there are sizable holes in between. During a heavy rainstorm the water runs behind the wall and washes fill through the wall and onto the turf. The customer is definitely interested in mitigating this in some way, but short of tearing down the walls and rebuilding them with smaller rocks, drainage and landscape fabric, I cannot come up with a quick fix. So my question is has anyone else ever run into a situation like this, and what have you tried to fix it?