After conducting research, it appears that there is no boat ramp named Powder House Cove located in Oregon with the provided latitude and longitude coordinates. Therefore, it is not possible to provide accurate information about the boat ramp's characteristics, including its width, the body of water it services, and the types of craft permitted on the water.

It is essential to ensure the accuracy of location information when conducting research to avoid misinformation. It is recommended to use reliable sources and double-check the information's authenticity before relying on it for any purpose.