The Oak Savannah Trail boat ramp in Merrillville, Indiana is a public boat ramp that provides access to Deep River. According to the latest information available, the boat ramp is approximately 20 feet wide and provides ample space for launching small to medium-sized watercraft.

The body of water serviced by the Oak Savannah Trail boat ramp is Deep River, which is a popular location for boating, fishing, and other recreational activities. Deep River is a slow-moving river that stretches over 16 miles through Lake County, Indiana, and is home to a variety of fish species, including largemouth bass, bluegill, and channel catfish.

As for the kind of craft permitted on the water, the latest information available suggests that the Oak Savannah Trail boat ramp is open to all types of watercraft, including kayaks, canoes, fishing boats, and small motorboats. However, it's essential to note that the use of personal watercraft such as jet skis is generally prohibited on Deep River.

In summary, the Oak Savannah Trail boat ramp in Merrillville, Indiana, is a public boat ramp that provides access to Deep River. The boat ramp is approximately 20 feet wide and can accommodate small to medium-sized watercraft. Deep River is a slow-moving river that is open to various types of watercraft, excluding personal watercraft such as jet skis.