In 1914, this small concrete pump house was built on the 600 foot Treadwell Wharf. Two 2,700 gallon per minute centrifugal pumps supplied salt water for milling operations and fire protection during the winter months. The pump house and surrounding pilings are all that remain of the wharf, where supplies for the Treadwell mines were landed and from which the gold bullion was shipped south. Warehouses, coal bunkers, and a machine shop stood on the wharf.
