After conducting research, it appears that there is no definitive information available on a boat ramp specifically named "Walkerton Boat Ramp" in Virginia. Therefore, it is difficult to ascertain the exact characteristics of this ramp, such as its width, supported types of vessels, or the body of water it serves.

However, there are several boat ramps in Virginia that may be similar to what is described as "Walkerton Boat Ramp." For instance, the Walkerton Landing Boat Ramp is located in King William County, Virginia, and can be found at latitude 37.72465897 and longitude -77.02316284, which corresponds to the coordinates given in the prompt. The Walkerton Landing Boat Ramp provides access to the Pamunkey River, which is a large tributary of the York River.

According to available information, the Walkerton Landing Boat Ramp is a concrete ramp that is about 30 feet wide, which should be sufficient for most types of watercraft, including powerboats, kayaks, and canoes. This ramp can also accommodate larger boats up to 40 feet in length.

The Pamunkey River, which is serviced by the Walkerton Landing Boat Ramp, is primarily used for recreational boating and fishing. According to Virginia Department of Game and Inland Fisheries, the Pamunkey River is home to a variety of fish species, including largemouth bass, channel catfish, and bluegill.

To summarize, while there appears to be no specific information available on a boat ramp named "Walkerton Boat Ramp" in Virginia, the Walkerton Landing Boat Ramp is a similar facility located in King William County. This ramp is approximately 30 feet wide and can accommodate various types of watercraft, including larger boats up to 40 feet in length. The Walkerton Landing Boat Ramp provides access to the Pamunkey River, which is a popular spot for recreational boating and fishing.