According to the Nebraska Game and Parks Commission, Keller Park SRA is a boat ramp located on the west bank of the Valentine National Wildlife Refuge. The boat ramp provides access to the Middle Loup River, which is a popular destination for kayaking, tubing, and fishing.

The commission states that the boat ramp at Keller Park SRA is a concrete ramp that is 12 feet wide and 100 feet long. This should provide ample space for the launch and retrieval of most watercraft.

As for the type of watercraft allowed on the Middle Loup River, the commission notes that it is a shallow river with tight turns and obstacles, so it is best suited for smaller boats and canoes. Kayaks, tubes, and other non-motorized watercraft are also permitted on the river. However, the commission does specify that motorized boats are not allowed above the Highway 20 bridge.

Based on the latest information available from the Nebraska Game and Parks Commission, it appears that Keller Park SRA is a suitable boat ramp for those looking to access the Middle Loup River with smaller watercraft.