There appears to be some confusion in the question, as the coordinates given are actually located in Memphis, Tennessee, not Illinois. Therefore, I will provide information on the boat ramps named Memphis in both states.

Memphis Boat Ramp in Tennessee:
According to the Memphis Riverfront Development Corporation, the Memphis Boat Ramp is a public boat ramp located at 740 Mud Island Road in Memphis, Tennessee. It provides access to the Mississippi River for boating and fishing. The ramp is reportedly 25 feet wide and can accommodate boats up to 30 feet in length. No specific information on permitted types of watercraft was found.

Memphis Boat Ramp in Illinois:
I was unable to find any information on a boat ramp named Memphis in Illinois. It's possible that such a ramp exists, but without additional information or clarification from the questioner, I cannot provide any further details.