To be precise, that would give you 17″ of adjustability in the upward direction and even more in the downward direction. Most folks want their leg-tops to line up nice and neat, so they are happy to measure their water depths. Some are less concerned about that, and only provide the water depth at the end of the pier, letting us interpolate the intermediate lengths. Still others guestimate or prefer to cut their legs after installation. The downside of that is that it’s more work to cut the legs “in situ” than it is to measure the water depths. We leave the preference to the customer. The minimum height that can be achieved from the footpad to the top of the deck is about 21″. There is no maximum leg length/water depth that can be achieved, however, from a practical standpoint, you certainly don’t want to put your pier into 50ft waters (unless you’re really tall). For deeper water we offer additional, easy-to-install crisscross bracing.