State and federal officials are working to document...the submerged remains of the Gold Rush era steamship Clara Nevada. The vessel was destroyed in an explosion 20 miles south of Haines [in the sea inlet in the Alaska Panhandle] in 1898.

Before being purchased by speculators and renamed, the steamer had spent more than 20 years charting southeast coastal waters as the U.S. Coast Survey vessel Hassler. The cause of the explosion that sank the vessel is a mystery...

Plans call for conducting an underwater investigation of the site in Lynn Canal this week. They hope to use the information gathered from that investigation to nominate the wreck to the National Register of Historic Places.

Alaska State Archaeologist Dave McMahan says the shipwreck is closely related to the Eldred Rock Lighthouse. The lighthouse was built after the wreck partly because of the incident. The lighthouse itself is already on the national register.