The Portage Lake boat ramp, located in Onekama, Manistee County, Michigan, is a concrete boat ramp that provides access to Portage Lake, which then leads to Lake Michigan. According to the Michigan Department of Natural Resources website, the ramp is 36 feet wide and can accommodate boats of various sizes.

The body of water that the Portage Lake boat ramp services is Portage Lake, which is a large inland lake located in Manistee County. Portage Lake is connected to Lake Michigan through a narrow channel, which is located at the eastern end of the lake.

According to the Michigan Department of Natural Resources website, a variety of watercraft are permitted on Portage Lake, including powerboats, sailboats, kayaks, canoes, and paddleboards. However, it is important to note that all watercraft must comply with the state's boating laws and safety regulations.

It is always important to check for updates and changes to information regarding boat ramps, as conditions can change due to weather or other factors.