For Seattle’s Next Light Rail Route, Sound Transit Weighs Short-Term Impacts Against Long-Term Gains

The plans show a deep Westlake station, similar to the new U District station pictured here.

By Lizz Giordano

The massive draft environmental impact statement (DEIS) for the West Seattle-Ballard Light Rail Extension landed on the Sound Transit website in late January. It lays out the pros and cons of a variety of elevated routes and tunnels as the agency attempts to weave light rail routes through some of the densest parts of Seattle.

Seattle’s second light rail line will begin at the current SoDo station and cross the Duwamish Waterway before skirting the northern edge of the West Seattle Golf Course toward Alaska Junction. The Ballard Spur will begin in Chinatown-International (CID), then head north through a new tunnel under Downtown toward Seattle Center, through Interbay, and above or below Salmon Bay to at its terminus in Ballard.

This extension will add a second transit tunnel through downtown to handle increased train volumes (including the new extension to Everett, also part of Sound Transit 3) and new stations near existing ones in Westlake , the CID and SoDo, which will become transfer points between the two light rail lines.

Some options offer better bus connections or greater potential for transit-oriented development. Other alternatives mitigate construction impacts by moving stations to the edge of the neighborhood or deep below ground.

While transit-oriented development isn’t the complete answer to Seattle’s housing crisis, building transit around train stations is a must. in south Seattle, where Sound Transit did not plan housing two decades ago, the sparsely populated light rail line represents a series of missed opportunities.

As Sound Transit’s board of directors makes a final decision on the route, expected in 2023, board members will assess the impacts of near-term construction versus building an easy and transparent that users can use for decades. These decisions might be a little easier now that the costs of elevated roads are similar to those of tunnels. But metro stations don’t always mean a better experience for users.

To keep some tunnel routes on the table for West Seattle and Ballard, as requested by many residents of those neighborhoods, Sound Transit board members representing King County offered a last-minute compromise by 2019. It stipulated that while agency staff would continue to study the more expensive tunnels, they would not move forward without third-party (non-Sound Transit) funding.

A few years later, the relentless increase in property values ​​made building above ground just as expensive as building a tunnel under the city for third-party financing.

In Ballard, where there are basically four options – an elevated or underground station at NW Market Street and 14th or 15th Ave. NW – the price of elevated options is now almost identical to the estimated cost of the tunnel: Between $1.5 billion and $1.6 billion, compared to $1.5 billion to $1.7 billion for tunnel variants.

As the cost difference has evaporated, Seattle Subway, a transit advocacy group, hopes to persuade the agency to revive an old proposed route along 20th Avenue Northwest that would bring passengers together in the heart of the neighborhood rather than several blocks to the east. Serving dense neighborhoods (rather than more car-centric areas on their outskirts) is a fundamental urban planning principle: high-capacity transit works best when it serves a dense core of ridership, and easy access to transportation in common can stimulate greater density in urban areas.

To completely resurrect this option, however, Sound Transit would have to create an entirely new environmental impact statement, which is no easy task and could add time to the project.

If this does not happen, the routes along 14th avenue NO could offer the best combination of public transport connections and development potential. The 14th Avenue location provides better transfers between buses and trains than the alternatives on 15th Avenue, while avoiding the need to build a drawbridge over Salmon Bay.

A buried road along 14th would also create opportunities for transit-oriented development on land owned by Sound Transit after construction – up to 450 homes and 70,000 gross square feet of retail space. While transit-oriented development isn’t the complete answer to Seattle’s housing crisis, building transit around train stations is a must. in south Seattle, where Sound Transit did not plan housing two decades ago, the sparsely populated light rail line represents a series of missed opportunities.

A similar price convergence is also occurring between above and below ground options in West Seattle, where stations are planned for the Junction, the Avalon area and North Delridge.

While a long requested tunnel route to preserve the views and “neighborhood character” of the West Seattle Golf Course at Alaska Junction – estimated cost: $1.7 billion – is still significantly more expensive than the two elevated options, which cost $900 million and $1.3 billion respectively. But a shorter tunnel route that would head underground past Avalon Station now costs $1.1 billion, less than even one of the above-ground routes.

Locating a station here at Alaska Avenue and Fauntleroy, one of the two preferred alternatives identified in the DEIS, offers less potential for transit-oriented development than building at 41st or 42nd, while also displacing a Safeway.

At Alaska Junction, future transit-oriented development depends more on the location of the station than on whether the line is elevated or buried. The 41st or 42nd Avenue SW stations have the potential to create slightly more residential units and commercial space on the remaining Sound Transit lands than if the station is farther east. Any type of station on 41st Avenue provides the best bus connection to what will become a terminus station, according to DEIS.

Although laying underground pathways minimizes construction impacts on the surface and generally displaces the fewest businesses and residents, it does not always lead to a better experience for future users. This is especially true if the journey out of these deep stations or between lines becomes its own stage of the journey.

At the new Westlake station downtown, Sound Transit plans to bury the train platform 135 feet below the surface, whichever alternative the council chooses, more than twice the depth of the existing station. The agency estimates that it would take most passengers three to six minutes to get from the street to the train platform – two escalators or two elevators, or a mix of the two (plus a staircase option on the last stage), depending on the agency.

Expect another long ride to the Midtown station platform on Fifth or Sixth Avenue in downtown Madison St., which will likely be buried even deeper: between 140 and 205 feet.

A proposed station in the Chinatown-International District would be 190 feet underground. That’s an estimated 3.5-minute elevator ride to the surface, which could get longer depending on the size of the crowd waiting at either end. By 2042, shortly after the station opens, these lines could become quite long during peak hours, with between 30,100 and 34,200 riders expected each day. For comparison, Beacon Hill station, also accessible only by elevator, is buried about 160 feet underground.

With deep tunnels too come longer transfer times. Westlake, CID station and SoDo will be the main transfer points between the lines.

Opportunities for shallower stations are limited, said Sound Transit spokeswoman Rachelle Cunningham, due to the composition of the ground and existing infrastructure.

“We need more explanation from them why this is so profound,” said Ben Broesamle of Seattle Subway. “Light rail has to be competitive with driving, and deep stations only add to travel time.”

The Chinatown-International District is keeping a close eye on route placement as the area faces a messy, years-long construction for the second station built to serve the new light rail extension. The underground station could run under Fourth or Fifth Avenue, and Sound Transit is investigating deep (190 feet) and shallow alternatives.

According to CID and Sound Transit executives, placing the station under Fourth Avenue would reduce the impact on the neighborhood during construction, instead of building one block to the east. It would also provide better integration with Sounder and Amtrak trains and with the main bus corridor along the avenue.

However, this option would take the most time and is also the most expensive alternative, as it would require rebuilding an overpass just east of Centurylink Field, causing the street to be closed for years. On the other hand, rebuilding the overpass now could save the neighborhood from future mess by replacing aging infrastructure as part of the light rail project.

Rebuilding the viaduct to accommodate the light rail would also reduce the roadway from six to four lanes, according to current plans. This redesign of the wide avenue between Union and King Street stations could be a catalyst to activate the space around the two stations.

While a station on Fifth would be the fastest transfer between light rail lines, it would also grab land in historic Seattle Chinatown. An entrance to the station would be a few steps from the Chinatown gate, according to the plans.

Sound Transit is accepting comments on the DEIS at [email protected] through April 28. The West Seattle segment is scheduled to begin operating in 2032, followed by the Ballard route in 2037 or 2039.

Jose P. Rogers