The next stage of the West Seattle-Ballard Light Rail extension is underway, as Sound Transit has identified alignment options for environmental studies.
The Interbay/Ballard alternatives to be included in the Draft Environmental Impact Study are as follows:
- Movable bridge with 15th elevated station – From elevated Interbay station, continues along 15th Avenue W and crosses Salmon Bay via a movable bridge west of the existing Ballard Bridge. Continues in an elevated guideway along 15th Avenue NW. Terminates at an elevated Ballard Station on 15th Avenue NW near NW Market Street.
- High fixed bridge with 14th elevated station – From elevated Interbay station, continues over 15th Avenue W, crosses Salmon Bay via a fixed bridge east of the existing Ballard Bridge and continues in an elevated guideway on 14th Avenue NW. Terminates at an elevated station on 14th Avenue NW at NW Market Street.
- Tunnel with 14th or 15th tunnel station – From Interbay station, descends into a tunnel beneath Salmon Bay. Terminates at a tunnel Ballard station with station options beneath 14th Avenue NW or east of 15th Avenue NW at NW Market Street.
- Tunnel with 20th tunnel station – Scoping comments suggested interest in a station farther west in Ballard with a tunnel crossing under Salmon Bay and tunnel station at 20th Avenue NW.
Sound Transit will work with the Federal Transit Administration (FTA) to prepare the DEIS. After the environmental evaluation and public/agency engagement, the Sound Transit Board will confirm or modify the preferred alternative. The Final Environmental Impact Statement (FEIS) is expected in 2020.
As a summary for each of these options, no one on the board wants to pursue the movable bridge for reliability reasons, but since that’s what was on the original ST3 Ballot they have to study it so they can have a baseline to show that the other options are better.
The high fixed bridge would be the better option from the movable bridge, would be a negligible cost increase (2% project cost) and would end at 14th. It would be a very tall bridge, would make the 14th Ave streetscape very different (think downtown Seattle monorail) and would be hard to continue the line North beyond market in future expansions, as they’d likely have to run right through the new gemanskap park. 14th is rather far from old Ballard, though they think that they could get bus integration to work
The better option is the tunnel to market/15th though now it’s +$350M (+7% increase) which seems doable funding wise if it’s worth it. 14th would not be disrupted, and the underground station could even be at 15th which is closer to old Ballard. My guess is this is the option they go for if they can find the $250M over the fixed bridge
The arguably best option for Ballard is the tunnel with a station on 20th/56th. That hasn’t been studied much, but the main issue is that with all the underground utilities below Ballard it looks very challenging to find a spot to sneak two tunnels through. It would likely be more in the +$700M range. But it would provide a walkshed that includes historic Ballard which is the center of the urban village. This would be awesome, but may not be technically feasible and would certainly be expensive.
Let’s hope the studies are fruitful!
the city of seattle will do whatever it chooses, no matter the harm or expense. replace who you can this upcoming council election. leave no one. it will be a start.
Why do you say “two tunnels” in your last paragraph?
They use separate tunnels for the Northbound and Southbound trains as that’s the most efficient way to do it. The tunnels are generally right next to each other, but if needed they can squeeze or go apart a bit in order to avoid hitting something. One big tunnel to fit both trains (like how Bertha did one tunnel for SR-99) requires a much larger tunnel boring machine and is less efficient space wise and requires more excavation.
Here’s a pic for a visual.
https://static.seattletimes.com/wp-content/uploads/2015/12/e9b26ecc-9ae7-11e5-8151-eebcb9f54b0e-780×432.jpg
How refreshing. An actual human, not a troll, providing useful, factual information that is helpful. Raising a glass to that!