as we let you know on Sep 20, CHSRA will hold the first of three Alignment Analysis Open House sessions in the SF peninsula this evening.
Wednesday, September 30, 2009
1250 San Carlos Avenue – San Carlos
6:00 – 8:00 pm
The other two will be held on Oct 9 in Sunnyvale and on Oct 13 in San Francisco, respectively.
The general process of how Alignment Analysis works is explained in this primer. CHSRA has also published exhibits, a set of slides detailing the alternatives under consideration in the SF-San Jose segment. These will be explained in more detail during the Open House sessions.
- Slide 1 shows an overview of the segment. In sections with more than one colored line, multiple options are still being considered at this stage. Obviously, only one will be implemented.
The slide does not show which - if any - rectifications of tight curves in the corridor are planned, nor the track order, nor the location of UPRR freight spurs. The freight rail operator has - unreasonably, IMHO - asked for full grade separation of the associated turnoffs against the HSR tracks.
- Slides 2, 3 and 4 describe variations of how Transbay Terminal Center and 4th & King facilities in SF could be utilized for HSR (focus on bottom 1/4 of each slide). For example, slide 4 shows the option of an HSR station either at or below grade at 4th & King only.
- Slide 5 shows the option of a Beale Street terminal instead of the TTC train box, with a tunnel not under but north of Embarcadero (i.e. under lots of buildings), apparently to avoid an 18 foot box sewer (PDF p42) identified by TJPA (h/t Andy Duncan).
The map below shows a staggered variation of my own that would cross under it twice but avoid tunneling under any buildings. Two full-length platform tracks would be intermodal with Embarcadero BART/SF Muni, another three would terminate within 300 feet of it. The thick red line indicates a two-track tunnel under Main Street, the TTC building would reduce to just a regular bus terminal, connected by pedestrian passages either above or below ground. This is just intended to illustrate one of many possible refinements of the Beale Street terminal idea - assuming it will be refined at all.
View SF Main St station in a larger map
Note that under CEQA, CHSRA is required to study a reasonable range of options, though it could be argued it already did so at the program level. The Beale Street terminal option was included in response to a comment received during the public comments period for the program level EIS/EIR, but the Transbay Terminal was eventually retained as the preferred option. CHSRA evidently considers it close enough to the TTC building to satisfy the AB3034 mandate that the SF station must be at the "Transbay Terminal".
It's not immediately clear if a station anywhere other than in the TTC train box would invalidate the Record of Decision that TJPA has already secured or its $400m application for HSR stimulus funds. Perhaps CHSRA ought to seek a compromise rather than invite the wrath of an entire city.
- Slide 6 shows the option of dedicated HSR tunnels all the way from 4th & King to Bayshore. Since HSR trains will be traveling at modest speeds in this section of the PCJPB corridor, it's worth asking if they shouldn't share tracks with Caltrain in tunnels #1 and #2 in the interest of saving money - even if that means modifying or closing Caltrain's 22nd Street station. UPRR's northernmost turnoff toward the mighty port of SF is at Oakdale Ave, just north of tunnel #3. An agreement to limit freight traffic north of Bayshore to nighttime operations would mean HSR and Caltrain could share all four of the old but serviceable existing tunnels, resulting in additional savings.
Sharing just two tracks north of Bayshore would be contingent on regulatory relief and high throughput signaling/timetable integration. It would not be possible further south, where the speed differential between Caltrain locals and HSR express trains is high.
- Slide 7 does not show UPRR's South San Francisco yard, where consists are assembled/disassembled during the day for transport down to San Jose and Fremont in the evening/at night.
Note that FRA-compliant heavy freight trains are limited to gradients of 1% whereas non-compliant HSR trains and Caltrain EMUs can tackle up to 3.5%. That makes a huge difference in the run length required for vertical transitions.
- Slide 8 appears to imply four tracks side-by-side through downtown San Mateo, either above or below grade. The PCJPB is currently just 51.5 feet wide between 2nd and 3rd Streets. Widening would require acquisition of adjacent land via voluntary transactions or eminent domain.
It's not clear to me if the expensive(!) potential alternative of two elevated plus two tunnel tracks is being considered as well. Including legacy tracks in elevated grade separation works that are will be used for HSR makes a lot of sense, but CHSRA arguably has no mandate to construct completely separate works for Caltrain alone.
- Slides 9 through 12 show that tunnel options are being considered for Redwood City, Atherton, Menlo Park, Palo Alto, Mountain View and even Sunnyvale. Several underground Caltrain stations are shown, implying tunnel sections with not just two but 3-4 tracks. Christmas must be coming early and very often this year.
Note that Mountain View is in the running for the mid-peninsula HSR station. The VTA light rail tracks already there are not shown as a potential conflict.
- Slides 13 and 15 illustrate the options of extra-high aerials and extra-deep tunnels in Santa Clara and north San Jose, to clear existing road overpasses and the future BART alignment, respectively. Because absolutely everything has to make way for BART, of course.
The massively cheaper at-grade option would probably require elevating the Santa Clara and College Park stations, though that option is not articulated. There are already
sixfive tracks under I-880 right now, it's not clear the support columns there would permit a sixth even if the others were moved. Caltrain's CEMOF facility would need to be scaled back to make room for HSR tracks at grade.
Fwiw, the right of way maps for mile posts 44 through 47 indicate that 95-100 feet of width are already available in most places.
Confusingly, the option for an at-grade HSR station is shown but tracks leading to it are not. Slide 15 indicates the option of a deep underground HSR station at San Jose Diridon is also now under consideration.