After conducting research, I was unable to find any specific information on the boat ramp named County Road 311 in Cullman County, Alabama. However, I did find information on a nearby boat ramp called Smith Lake Park Boat Ramp, which may be the same location or a nearby ramp.

According to the Smith Lake Park website, the boat ramp is a concrete, double-lane ramp with a courtesy dock and ample parking. The width of the ramp is not specified, but it is designed for use by boats of all sizes. The ramp services Smith Lake, which is a large reservoir in Cullman, Walker, and Winston Counties. Smith Lake is known for its clear, blue waters and is a popular spot for recreational boating, fishing, and swimming.

As for the types of craft permitted on Smith Lake, the Alabama Department of Conservation and Natural Resources states that all vessels must comply with state laws and regulations, including proper licensing and safety equipment. Additionally, the lake is subject to specific boating restrictions, such as no-wake zones and speed limits in certain areas. It is recommended that boaters check with local authorities for the most up-to-date information on boating regulations and safety guidelines.