I apologize, but there seems to be an error in the question. Boardman Avenue Sterlington boat ramp is not located in Missouri, but in Louisiana. The correct location is Sterlington, Louisiana, USA, with the coordinates 32.69937515, -92.0842514.

According to the latest information available, the Boardman Avenue Sterlington boat ramp is a concrete ramp with a single lane. It is approximately 20 feet wide and has a moderate slope. It services the Ouachita River, which is a popular destination for fishing and recreational boating.

The Ouachita River is navigable by a variety of watercraft, including motorboats, pontoons, kayaks, and canoes. However, there are certain regulations and restrictions in place. For example, all boats must have proper registration and safety equipment, and there are specific speed limits in certain areas of the river.

In summary, the Boardman Avenue Sterlington boat ramp is a concrete ramp located in Sterlington, Louisiana, USA, with coordinates 32.69937515, -92.0842514. It services the Ouachita River and is approximately 20 feet wide with a moderate slope. The Ouachita River is navigable by a variety of watercraft, but there are certain regulations and restrictions in place to ensure safety and compliance.