A boat-access only beach area with forested upland, the Spillman Beaches marine site has one of the better quality beaches on Adams Lake, popular for fishing and boating. No facilities are provided at this site. This park protects an alluvial fan and the lower reaches of Spillman Creek. This park also contains mixed Douglas-fir/lodgepole pine forest with birch and cottonwoods as well as western red cedar in the north. There are small pockets of grassland, shrubs and forbs on the drier sites.