California State Route 161 is a nineteen mile State Highway aligned along State Line Road between US Route 97 and California State Route 139. California State Route 161 bisects what remains of Lower Klamath Lake and is one of the easier ways to access Lava Beds National Monument. The entirety of California State Route 161 is part of the Volcanic Legacy Scenic Byway
Part 1; the history of California State Route 161
The development of modern California State Route 161 ("CA 161") is tied heavily to that of the Klamath Reclamation Project within the Klamath Basin. Historically Lower Klamath Lake and Tule Lake were an interconnected fresh water marsh fed by waters seeping from the Cascade Range. Lower Klamath Lake, Tule Lake and Clear Lake can be see seen obstructing direct overland access along the California/Oregon State Line on the 1873 Bancroft's Map of California and Nevada.
In 1905 the Federal Government announced it would fund the Klamath Reclamation Project which would drain much of the Klamath Basin for agricultural use. The A Canal was constructed during 1906 and began delivering diversions from the Klamath River and Upper Klamath Lake in 1907. The Southern Pacific Railroad plotted a line through the Klamath Basin in 1909 which tied many of the existing communities such as Klamath Falls and Merill. In 1910 Clear Lake Dam was completed which was followed by the Lost River Division Dam in 1912. Anderson-Rose Dam and the Link River dam was completed by 1921 which was followed by the Malone Division Dam on the Lost River in 1923. The early development of the Klamath Reclamation Project led to a population boom in the Klamath Basin which lasted until the onset of the Great Depression.
Klamath Basin can be seen on the 1924 Rand McNally Map of California and Oregon. Despite the infrastructure developments via the Klamath Reclamation Project the existing road network still had to diverge around Lower Klamath Lake and Tule Lake.
"near Canby to the Oregon State Line near Merrill" "to the state highway system, provided that the United States Government, through its agencies the Bureau of Public Roads and Forest Service construct or reconstruct with highway funds or any other funds made available by congress for highway purposes within the state of California."
LRN 210 and 1939 Legislative Chapter 338 is referenced in the October 1939 California Highways & Public Works. LRN 210 is described as a new highway under construction by the Federal Government in Modoc National Forest between Canby (US Route 299) north through Modoc County to the Oregon State Line near Merrill. This new highway was to be assumed by the California Division of Highways upon completion.
1943 California Legislative Chapter 964 repealed the 1939 stipulations of LRN 210 leaving only the route definition. This action was taken upon the completion of the new highway through Modoc National Forest which subsequently was turned over to the California Division of Highways. CA 139 appears for the first time on the 1944 Division of Highways Map aligned over LRN 210 from the Oregon State Line through Modoc National Forest to US Route 299 near Canby. The numbering of CA 139 seems to have been chosen to provide route continuity with OR 39. CA 39 was not available for use given it was among the original Sign State Routes defined in the August 1934 California Highways & Public Works. The completion of the new highway through Modoc National Forest by the Bureau of Public Roads likely was a priority during World War II due to the internment camp located at Tulelake.
Returning to CA 161 westbound the highway intersects Malone Road at Postmile SIS 17.20. Malone Road is signed as access to Merill, Oregon and Oregon Route 39.
CA 161 westbound terminates at US Route 97 four miles north of Dorris.