U.S. Coast Guard puts a fork in Ballard light rail plans

Sound Transit’s plans for the future Ballard light rail will need reconsideration in light of the U.S. Coast Guard’s height determination for bridges along the Lake Washington Ship Canal. 

This determination would require fixed bridges along the Ship Canal to have a vertical height clearance of at least 205 feet; bridges like the one that will have to be built to connect the future Ballard Link Station to Interbay Station. 

Rendering of a fixed bridge over Salmon bay extending from 14th Ave NW. Its current design plans put it at 136 feet, nearly 70 feet below the Coast Guards’ height requirement. (Photo Credit: Sound Transit)

The Coast Guard’s reasoning behind this requirement stems from comments that documented a current and verified future need to support vessels with a mast height greater than 136 feet (i.e., superyachts) east of the current Ballard Bridge. 

Currently, there are four alternative plans for the construction of the Ballard Link Station, two of which require a bridge to be built along Salmon Bay. None of these plans would meet the 205-foot height requirement; current designs place the bridge height at 136 ft. 

A map of these alternatives can be seen below (provided by Sound Transit):

(Credit: Sound Transit)

The four alternatives plans for Ballard Link Station include the following: 

  • Elevated 14th Avenue Station (Prefered alternative)
    • Elevated station on the east side of 14th Avenue Northwest straddling Northwest Market Street (highlighted above in pink)
  • Tunnel 14th Avenue Station (Preferred alternative with third-party funding)
    • Tunnel station beneath 14th Avenue under Northwest Market Street (highlighted above in brown on 14th Ave NW)
  • Tunnel 15th Avenue Station (Preferred alternative with third-party funding)
    • Tunnel station beneath the east side of 15th Avenue Northwest south of Northwest Market Street (highlighted in brown on 15th Ave NW)
  • Elevated 15th Avenue Station
    • Elevated station on the east edge of 15th Avenue Northwest south of Northwest Market Street (highlighted in blue on 15th Ave NW)

Last August, in an effort to curb an affordability gap of $6.5 billion exacerbated by the pandemic, Sound Transit adopted a hybrid plan. This plan would push back the construction of the Ballard Station from 2037 to 2039 if greater funds cannot be acquired from the local, state, and national levels. A reduction in costs is also something Sound Transit hopes will alleviate this gap. 

The construction of the Ballard Station currently has projected costs ranging above a billion (seen below). However, with additional design work needed to fully understand how the Coast Guard’s height determination would affect current bridge concepts, this affordability gap may change. Alternative bridge concepts are also being considered.

“Potential revised bridge concepts could possibly include moveable bridges or higher fixed-height bridges,” said Sound Transit public information officer, Rachel Cunningham in an email to My Ballard.

(Credit: Sound Transit)