After conducting online research, I was unable to find specific information about boat ramp named County Road 31 51047 in Otter Tail County in Minnesota. However, I can provide some general information about boat ramps in the area.

Boat ramps in Otter Tail County are typically concrete or gravel and can vary in width. They service a variety of bodies of water in the area, including lakes, rivers, and streams. The type of craft permitted on the water can also vary depending on the body of water. Some lakes may have restrictions on the size or speed of boats allowed, while others may permit all types of watercraft.

It's important to note that regulations and restrictions may change over time, and it's always best to check with local authorities or park rangers for the latest information before using a boat ramp or getting out on the water.