If your catch basin is at an odd height, there’s an easy way to fix that. Just dig out a little deeper and add a riser. FDM's 6 in. Catch Basin riser adds 1.5 inches of height. If you need more than 1.5 inches of lift, simply stack the risers on top of each other and build to your desired height. We also sell a 6 in. Riser with 5 in. of lift at the link below. 6 in. Catch Basin Stackable Riser with 5 in. Lift Both of our 6 in. risers are interchangeable. For example, if you need to lift your basin 6.5 inches, you could stack one Riser with 5 in lift and one Riser with 1.5 in lift, as opposed to stacking 4-5 of the shorter risers.