Complex sentence: The "W.T. Preston" is a specialized sternwheeler that operated as a snagboat, removing log jams and natural debris that prevented river navigation on several Puget Sound-area rivers from Olympia up to Blaine, including the Skagit, Stillaguamish, and Snohomish rivers.
Split into simpler sentences: The "W.T. Preston" is a specialized sternwheeler that operated as a snagboat, removing log jams and natural debris that prevented river navigation on several Puget Sound-area rivers. The W.T. Preston operated from Olympia up to Blaine, including the Skagit, Stillaguamish, and Snohomish rivers.