According to the official website of the Washington Department of Fish and Wildlife, the Green Lake Road 50-374 boat ramp is a concrete single-lane ramp that provides access to Green Lake. The ramp is approximately 10 feet wide, and there is a small parking lot adjacent to it that can accommodate up to 10 vehicles.

Green Lake is a small, shallow lake located in Okanogan County in north-central Washington. It is known for its abundant population of Largemouth Bass, as well as Yellow Perch, Black Crappie, and other warmwater fish species. The lake is also popular for boating, swimming, and other recreational activities.

According to the same source, all types of watercraft are permitted on Green Lake, including motorized and non-motorized vessels. However, there are some restrictions on the use of motorized watercraft. Specifically, boats with motors exceeding 10 horsepower are not allowed on the lake, except for boats used by the Washington Department of Fish and Wildlife for fishery management purposes.

Based on this information, it can be concluded that the Green Lake Road 50-374 boat ramp is a small, single-lane concrete ramp that provides access to a shallow lake that is primarily used for freshwater fishing and non-motorized boating. The ramp is suitable for small boats and non-motorized watercraft, and there are some restrictions on the use of motorized vessels.