The joint Sound Transit/WSDOT Environmental Impact Statement (EIS) defined the need for I-90 improvements with statements like “Transit demand across Lake Washington is expected to nearly double in the next 30 years” and to “Meet growing transit and mobility demands by increasing person-moving capacity across Lake Washington on I-90 by up to 60 percent”.
Neither organization apparently recognized the only way to provide the needed capacity was to move non-transit HOV to a 4th lane on each outer roadway and divide the center roadway into two-way bus only lanes. Both changes could have been easily implemented ten years ago. The bus lanes could easily accommodate not only current bus routes but also the bus rapid transit (BRT) service between every eastside P&R and Seattle needed for future growth.
East Link problems will begin in 2016 when ST (finally) completes adding the 4th lanes (the R8-A configuration) to the bridge outer roadways and closes center roadway to install light rail. A 2004 FHWA study concluded the single lane would not have the capacity to accommodate both non-transit HOV and buses. The likely result will be the 4th lanes will be reserved for transit buses; increasing congestion for vehicles on the 3 general-purpose lanes.
What’s “remarkable” is the fact I-90 commuters after enduring years of ever increasing congestion on the outer roadway will face increased not decreased congestion when light rail begins operation (2023?).
First of all East Link light rail will never have the capacity for “up to 24,000 riders per hour” ST promised in the EIS. East Link operation will likely consist of one 2-car train every 8 minutes. It will provide up to 4440 rph. While a 4-car train is feasible, the capacity will never attain promised capacity. (ST chose to demonstrate Light rail/1-90 Bridge compatibility with only a 2-car train)
ST plans to use whatever light rail capacity is available by transferring all cross-lake bus riders to light rail at either the South Bellevue or Mercer Island stations. They claim 40,000 of the 50,000 projected riders will come from terminated bus routes.
The 20,000 transit riders who previously had relatively direct rides into Seattle on the outer roadway will be forced to exit their bus at one of the two stations and join others waiting to get on light rail cars. Light rail’s limited capacity (2220 rph for 2-car train in each direction) and the fact the 2 stations are the last of 8 on the east side will likely result in “crowded” cars. Even 4-car trains would take nearly 5 hours to accommodate the 20,000 riders.
Return commuters, rather than an easy bus ride from Seattle to their P&R or other destination will be forced to exit the train and wait at the light rail station for their return bus. This “transfer scenario” will undoubtedly result in fewer rather than more transit riders with East Link.
Only time will tell how many commuters will eventually choose to drive rather the ride. Those with longer commutes may be more willing to accept the inconvenience. Those using Eastgate or Issaquah P&R lots may be more likely to drive. Whatever the final number, every terminated bus will likely result in an additional 5, 10, 20, or more additional vehicles on an already crowded outer roadway. Especially in view of ST projected increase in cross-lake commuters.
Sooner rather than later, cross-lake commuters, sitting in gridlocked traffic on the outer roadway, will recognize the insanity of using the center roadway to allow 2 or 4-car trains to cruise pass every 8 minutes. Once that happens, it’s only a question of time before commuters demand light rail be torn out and replaced by two-way bus only lanes.
Surely by 2030, commuters will be able to leave their cars at a P&R near where they live and have a non-stop bus (BRT) ride into and out of Seattle. The additional transit riders will ease congestion throughout the east side. The tragedy will be it wasn’t done 25 years earlier, saving billions and years of cross-lake congestion as well as avoiding devastation to Bellevue.