This pasts weekend I took California State Route 89 over the 12 mile routing from CA 88 in Alpine County over the 7,740 foot Lurther Pass to US 50 in El Dorado County.
CA 89 through Luther Pass was first proposed as a State Highway in 1909 on a bond measure that was approved in 1910. Eventually the State Highway through Luther Pass was assigned to Legislative Route Number 23. More information can be found here regarding the actual legislative acts on CAhighways.org.
CAhighways.org Early Highway History
CAhighways.org on CA 89
LRN 23 can be observed south of Lake Tahoe on the 1918 State Highway Map over Luther Pass as a special appropriations road.
1918 State Highway Map
The original alignment of LRN 23 and CA 89 through Luther Pass was on Upper Truckee Road. The original alignment through Luther Pass used part of the modern CA 89 alignment but was on the west bank of the Upper Truckee River as opposed to the east bank. This alignment can be seen clearly on the 1935 California Division of Highways Maps of Alpine and El Dorado Counties.
1935 Alpine County Highway Map
1935 El Dorado County Highway Map
I prepared the below graphical illustration showing the original alignment of CA 89 through Luther Pass. The map also includes the original alignments of US 50 over the south route of the Lincoln Highway over Johnson Pass and the original south terminus of CA 89 at CA 8/89 which was located at Picketts Junction.
CA 89 wasn't signed south of CA 88 until 1957 which can be observed by comparing the 1956 and 1957 State Highway Maps.
1956 State Highway Map
1957 State Highway Map
By 1960 CA 89 was shifted east of the Upper Truckee River.
1960 State Highway Map
By 1961 the modern route CA 89 takes over Luther Pass to CA 88 was complete.
1961 State Highway Map
From the West Fork Carson River at CA 88 the routing CA 89 northbound over Luther Pass has an ominous appearance but is actually a fairly tame grade.
Heading northbound on CA 89 the El Dorado County Line is quickly encountered at Luther Pass.
Most of Upper Truckee Road is still maintained but the grade south of Luther Pass to CA 88 has been abandoned. The abandoned portion of Upper Truckee Road is easily found at Luther Pass and is generally known as a local hiking trail.
As noted above in the Luther Pass photo the downhill grade on CA 89 is 6% downhill for the next 6 northbound miles. Upper Truckee Road is encountered again twice on the downhill descent.
As CA 89 is descending from Luther Pass US Route 50 can be seen above descending Echo Summit.
CA 89 soon enters Meyers where it meets US 50. CA 89 multiplexes US 50 to South Lake Tahoe before splitting away towards the southwest corner of Lake Tahoe.