The Ash Way direct access ramp is open only to transit because allowing carpools and vanpools to use the ramp would create safety hazards and building the ramp to safely accommodate both transit and carpools/vanpools was prohibitively expensive. Sound Transit provided funding for these new ramps. WSDOT managed its design and construction but did not provide funding.
Sound Transit's direct access ramp program
The Ash Way Park-and-Ride Direct Access Ramp project was entirely financed by Sound Transit as part of its transit improvement program. The primary goal of Sound Transit's direct access ramp transit improvement program is to improve bus speed and reliability by eliminating congestion points along transit service routes. To achieve this goal, they are financing construction of numerous direct access ramps throughout the Puget Sound region. These ramps directly connect transit centers and park-and-ride lots with freeway HOV lanes. They eliminate the need for buses to weave through lanes of traffic to enter and exit HOV lanes.
Carpools and vanpools on direct access ramps
The primary goal of Sound Transit's direct access ramp transit improvement program is to improve bus speed and reliability. Sound Transit will fund direct access ramp improvements that also accommodate carpools and vanpools where the ramps can be built to do so safely, economically and while preserving the benefits to transit. Direct access ramps in Bellevue and Lynnwood are open to transit, carpools and vanpools. Direct access ramps currently under construction in Federal Way and Totem Lake will also be open to transit, carpools and vanpools.
Why would including carpool/vanpool access have diminished transit benefits and significantly increased the cost of the Ash Way ramp?
• Ramp access to the Ash Way park-and-ride lot
The existing park-and-ride lot provides parking for transit customers and a transit center. The parking lot and the transit center are physically separated to eliminate conflicting movements between buses and other vehicles and to provide safe pedestrian access to the bus bays. Since the primary purpose of any new direct access ramp funded by Sound Transit is to provide a connection for buses to the HOV lanes on the freeway, the ramp at the park-and-ride had to connect to the bus loop in the transit center. If carpools and vanpools were also allowed to use this ramp, they would need to exit the parking lot and then enter the bus loop at the transit center. The introduction of this traffic to the bus loop would increase the likelihood of conflicts between buses, pedestrians, carpools and vanpools, thereby impeding the safe and efficient operation of the transit center.
• Separate ramp access for carpools and vanpools considered
Because the introduction of carpool and vanpool traffic to the bus loop was not desirable, other alternatives were considered during planning and design that would have provided separate access from the parking lot portion of the facility to the direct access ramp. Each of these alternatives would have added to the cost of the project.
The most feasible and least expensive of these alternatives would have eliminated a significant number of parking stalls. Since demand for park-and-ride stalls in Snohomish County south of Everett exceeds the supply, elimination of any stalls was undesirable. Safety concerns would not have been entirely eliminated with separate access because pedestrians would have had to cross the separate access ramp from the parking lot to get to the transit center, and carpools and vanpools would still interact with buses on the on-ramp.
• Preventing traffic from weaving across I-5
Because the park-and-ride is very close to the exit from I-5 to I-405, WSDOT and the Federal Highway Administration had serious concerns that carpools and vanpools using a direct access ramp from the park-and-ride would attempt to leave the HOV lane in the center of the freeway and cross multiple lanes of I-5 to exit to I-405.
At direct access ramps in Bellevue and Lynnwood, Sound Transit was required to provide a four-foot-wide painted barrier area on the pavement to separate the HOV lane and the general purpose lanes. This discourages drivers from making hazardous movements to I-405 and SR-520. This same barrier area would have been required on southbound I-5 for the Ash Way Direct Access Ramp and could have been created by widening the freeway.
Installing four feet of additional roadway adjacent to the new southbound ramp would have required 4,100 feet of new pavement, the acquisition of additional wetland mitigation property, construction of the additional environmental mitigation, and additional drainage collection and treatment facilities. This would have significantly increased the project cost.