California State Route 281 exists as a mostly unbuilt State Highway along Soda Bay Road of the southern shore of Clear Lake.
Present California State Route 281 ("CA 281") is a 3 mile State Highway which follows Soda Lake Road northward from CA 29 towards Konocti Bay of Clear Lake. In terms of scale only 3 of the 17 planned miles of Soda Bay Road have been assumed under Caltrans maintenance as CA 281.
The current scale of CA 281 is observable in the Caltrans Post Mile Tool. The 3 constructed miles of CA 281 appear
in the Caltrans Post Mile Tool as Post Mile LAK 14.0-17.0 on Soda Bay
Road. Soda Bay Road northwest to CA 29 more or less is the implied
connection of CA 281 beyond State Maintenance.
Part 1; the history of California State Route 281
The genesis of CA 281 as a State Highway is somewhat recent having been given a Legislative description in 1970 according to CAhighways.org. The the definition of CA 281 was given during 1970 Legislative Chapter 1473 as:
Most Legislative Routes adopted under 1970 Legislative Chapter 1473 were contingent upon a local authority building an existing highway up to State Standards before maintenance would be assumed. CA 281 appears in it's current configuration on the 1975 Caltrans Map which suggests that Lake County was only able to fund 3 miles of building Soda Bay Road to State Standards.
To that end Soda Bay Road has been around for a significant period of time as it can be seen on the 1917 California Automobile Association Map.
Soda Bay Road can be seen in detail as a minor highway on the 1935 California Division of Highways Map of Lake County.
Part 2; a drive on California State Route 281
CA 281/Soda Bay Road begins from CA 29 between Kelseyville and Lowerlake.
CA 281/Soda Bay Road initially jogs north 2 miles and passes through Clear Lake Riviera at Postmile LAK 15.00.
The final mile of CA 281 follows Soda Bay Road northwest towards a vista of Clear Lake and Konocti Bay.
CA 281 terminates at Postmile LAK 14.00 and has a well placed "end" placard. There is a visible contract in Soda Bay Road as it transitions to Lake County Maintenance.