Port Angeles Harbor is located on the northern coast of Washington’s Olympic Peninsula on the Strait of Juan de Fuca. The peninsula is bordered by the Strait of Juan de Fuca to the north, the eastern Pacific Ocean to the west, and Hood Canal/Puget Sound to the east. Protected from storms from the Pacific Ocean by the 2.5-mile-long arm of Ediz Hook, the harbor was home to two aboriginal Klallam fishing villages and continues to provide safe harbor for commercial ships, fishing vessels, and pleasure craft. Several surface streams drain into the Harbor, including Tumwater; Valley; Peabody; Morse; and Ennis Creek. Ennis Creek, which drains a significantly-sized area, is a snow fed stream with its headwaters located in Olympic National Park.

The City of Port Angeles includes approximately 26 miles of marine shoreline. Port Angeles Harbor is considered the largest natural deepwater harbor on the west coast of the United States, with depths exceeding 90 feet near the eastern end. The Harbor has many commercial and industrial facilities along its shoreline. Over the past century, the Harbor has been used by a number of industries including saw mills and plywood manufacturing, pulp and paper production, marine shipping/transportation, boat building and refurbishing, petroleum bulk fuel facilities, marinas, and commercial fishing. Since the early 1900s, pulp and paper mills have comprised a dominant portion of Port Angeles’ industrial sector. Treated and untreated mill process effluents were commonly discharged into the Harbor from wood product sources and have been identified as significant sources of constituents of potential concern to marine sediments.