LETTER: Call for Sound Transit Board to re-consider aerial transit-gondola systems in new EIS
From Martin Westerman, Joyce Hengesbach, Martin Pagel, et al., West Seattle / 206-427-9039
We ask for a new study of aerial cable transit (ACT) as an option for linking West Seattle with SoDo & International District light rail trunk lines. We want Sound Transit to use the best mobility option for the purpose, and ACT is best for hilly topography. But ST’s 2014 High-Capacity Transit Technologies Issue Paper rejected ACT, based unfortunately on many inaccuracies and omissions.
Omissions and elements not considered:
- State law: RCW 81.104.015 (2) and (4) define aerial as HCT if it is integral to a rail fixed guideway system. So ST 2014 paper views ACT as the best circulator option
- Comparative cost: $64M /mile for ACT, $500M-$600M /mile for light rail
- Seismic safety. Rigid, closely-spaced light rail pylons supporting rigid guideway may be considered less seismically sound than widely-spaced aerial pylons supporting flexible cable
- Successful urban ACT systems in Singapore, Vietnam, Europe and South American cities, and proposed systems for Edmonton, Miami, Oakland, Los Angeles and San Diego
- Equity (social & business) impacts: Aerial –
- requires fewer rights of way purchases and eminent domain takings,
- creates a smaller footprint than light rail, displaces fewer people, and leaves more space on the ground for housing, businesses and parks, and
- delivers faster “return to normal” with less construction time and disruptions,
- Safety record: excellent worldwide. If necessary, “rescue” of stalled gondolas can be handled with ground (fire dept.) or on-system (tow unit) resources
- More terrain appropriate.
- Light rail is designd for level and moderate slopes, and requires elevated structures and tunnels in hilly and water areas; gondola is designed for hilly and water area geography.
- Passenger capacity: the Paper lists “Low to Moderate” (2000 passengers per hour (pph)); RCW 81.104.015 says aerial systems are HCT (and deliver 5000-6000 pph)
- Operating speeds: report lists 10-15 mph; actual speed can reach 20 mph
- Headway: report states “as low as 40 seconds”; actual headways – as low as 30 seconds
- Implementation risk: report states “high”; actual risk — moderate to low
- “...gondolas/aerial trams ...are more appropriate for local travel over shorter distances”
- According to ST 2014 paper, ACT is best option to link W. Seattle with SoDo & I.D.
- ACT can extend up to eight miles, the distance from Fauntleroy to downtown, and from Golden Gardens and Northgate to downtown Seattle.
- Suggested West Seattle system route would extend four miles
- Aerial “lacks regional applications,” and each application would require new supporting facilities and services.”
- ACT is proposed as a link to light rail trunk lines, not as a regional system
- ACT requires a much smaller maintenance base and stations than light rail
- Metro buses need supporting facilities & services; electrics will need upgrades
The report was accurate around:
- infrastructure requirements — ACT does require ROW purchases and eminent domain takings, but far fewer, and needs much less support infrastructure than light rail
- system integration — transfers are required between all different mode stations
- schedule reliability — excellent