The unsurfaced 35-mile Rim Road was completed, with the exception of eight miles that required further widening and grading, and opened to the public on August 2, 1918. By an Act of Congress of July 19, 1919, the road engineering work in Crater Lake National Park was transferred from the Corps of Engineers to the National Park Service. All property and equipment of the corps that had been purchased with park funds were delivered to the Park Service, and anticipating the transfer the corps placed the direction of the improvement work under Superintendent Sparrow at the beginning of the 1919 summer season. With the transfer of this engineering work the National Park Service, according to Mather "gained complete control of the last national park in which authority was divided between it and the War Department."

In 1926 National Park Service engineers revised the road program for the park that had been devised by army engineers some years before. The new plans were coordinated with the Bureau of Public Roads, which took over road construction in the park on January 1, 1926, with District Engineer C.H. Purcell of Portland in charge. The revised plans provided for improvement of existing roads by regrading, resurfacing, and realignment."

Credits and Sources:

Unrau, Harlan D., “Crater Lake National Park: Administrative History,” U.S. Department of the Interior National Park Service, http://www.craterlakeinstitute.com/online-library/administrative-history/adminhistory.htm#A._DISCOVERY_OF_CRATER_LAKE_BY_JOHN_W._HILLMAN:_1853,Accessed June 29, 2015.