Ameren writes different length limits for coves and for the main channels. Naming the arm, and saying whether you are in a cove or on the channel, is the difference between a drawing that fits and one that does not.
Lake Ozarks Dock & Lift is operated by Blake Reitnauer as a referral service. It is not a dock builder, not an Ameren-certified dock builder, and not affiliated with Ameren Missouri. Requests are referred to one independent Ameren-certified dock builder, not to a list of contractors.
Appendix B measures docks shore to shore, perpendicular to the channel, at the dock. It then applies one set of limits in coves and another on the main channels. The channels it names include the Osage, Gravois, Grand Glaize, Niangua, and Little Niangua.
Gravois Arm, with Sunrise Beach, Laurie, and Gravois Mills
Niangua Arm, the mid-lake arm many Camdenton owners actually have a dock on
The numbers themselves live on the size-limit page. These arm pages are about which number applies to you, and which town page to read next. The permit guide is the paperwork either way.
Questions
What about the Grand Glaize?
FERC lists the Grand Glaize as a major arm too. It is covered with Osage Beach, where that arm meets the lower lake. The same cove and channel measurements apply. Name Grand Glaize on the form if that is your water.