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From Route 580 near Point San Quentin to Route 101 near Greenbrae.
As initially defined in 1963, this segment was the entire route, and was defined as “Route 101 near Greenbrae to Route 17 near Point San Quentin.”
In 1984, Chapter 409 reordered this segment and changed "Route 17" to "Route 580".
Originally, this was to have been the "Point Reyes" Freeway. It was originally part of Route 17 from 1963 to the mid 1980's, when Route 17 was deleted in Marin County as part of the renumber of Route 17 to I-580 and I-880. The Pt. Reyes Freeway was one of many new routes created in the State Freeway and Expressway System, which was approved by the Legislature in 1959. This route has all but been killed by environmental concerns and costs. It would have connected with Route 37.
In 2002, the Traversable Highways report showed this as "to be improved" in 5 years, but this appears to never have happened. The traversable route is Sir Francis Drake Road. There is a 4-lane section for 1.0 mile, and a 40' section for 0.5 mile. The existing underpass has only a 14' clearance. This is used as a cut-off between US 101 and the Richmond-San Rafael bridge.
This segment corresponds to pre-1963 LRN 251, defined in 1959. This is one of the few whose sign routes equals their pre-1963 legislative routes.
This routing is unconstructed. For the US 101 to I-580 segment, the traversable route is Sir Francis Drake Blvd. The remainder of the traversable local routing includes Petaluma Pt. Reyes Road, and Nicasino Valley Road. These roads are not constructed to state standards. There are no plans for Caltrans to adopt this routing.
From Route 101 near San Rafael to Route 1 near Point Reyes Station.
In 1984, Chapter 409 added segment (b) as a result of a transfer from Route 17, giving: “(a) Route 580 near Point San Quentin to Route 101 near Greenbrae. (b) Route 101 near San Rafael to Route 1 near Point Reyes Station.”
This was a proposed (routing determined) segment of Route 17. It was part of LRN 69, defined in 1933. This appears to correspond to Francis Drake Blvd. There is an interchange with several flyover ramps at the junction with US 101; this may have been planning for a future freeway Route 251.
This routing is unconstructed. For the US 101 to I-580 segment, the traversable route is Sir Francis Drake Blvd. The remainder of the traversable local routing includes Petaluma Pt. Reyes Road, and Nicasino Valley Road. These roads are not constructed to state standards. There are no plans for Caltrans to adopt this routing.
[SHC 253.1] Entire route; unconstructed. Added to the Freeway and Expressway system in 1959.
Overall statistics for Route 251:
In 1959, Chapter 1062 defined LRN 251 as “[LRN 1] near Greenbrae to [LRN 69] near Point San Quentin.” This is one of the few routes that retained the same number post-1963. It is still Route 251.
© 1996-2020 Daniel P. Faigin.
Maintained by: Daniel P. Faigin
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