I plan to remove US 50 Alternate (Pollock Pines) from the usausb route set, in my next batch of California updates. I would also move the Forest Service part of the route, the Mormon Emigrant Trail, into the usanp route set. Most of the rest of US 50 Alternate is also in the preview usaca route set.
US 50 Alternate was established circa 1997,
not as a conventional permanent alternate route, but rather than as a long-term but temporary detour around prolonged US 50 landslide closures, over a mix of county, Forest Service, and state highways. It was never officially part of the state highway system, except two segments concurrent with parts of CA 88 and CA 89.
US 50 Alternate signage remained, but usually covered up except when US 50 traffic had to be detoured again (though it was left uncovered in July 2011, when traffic was not being detoured off US 50). When Caltrans had to detour traffic around US 50 bridge reconstruction for two weeks last year,
Caltrans designated different and longer detours, rather than resume use of US 50 Alternate, so US 50 Alternate may have outlived its usefulness as an alternate route.
I was reluctant at first to deep-six US 50 Alternate, in part because I went through a lot of trouble to clinch the Mormon Emigrant Trail (took me three tries, the first two foiled by snow closures, one of them in early July -- the Forest Service seems to prefer "solar snow removal" to calling in the snowplows). But it uncomfortably resembled designated detour routes in other states, including a lot of signed alternate Interstate routes in Wisconsin, that we don't include in TM.
As neroute2 and Si suggested, I'll add the Mormon Emigrant Trail part of US 50 Alternate to the usanp route set. The Trail is a scenic route maintained by the U.S. Forest Service. The rest of US 50 Alternate would be left out of usanp, because it's covered by the preview usaca route set (CA 88 and CA 89), or is a county road.
