The ST Stride/ WSDOT I-405 Problem

The previous posts detailed how the May 8th System Expansion Committee meeting video showed they didn’t recognize the folly of attempting to use the ST3 extensions of light rail to reduce congestion into Seattle. This post details why the committee video, and subsequent approval by the Sound Transit Board, of their plans for Stride BRT won’t reduce I-405 congestion.

A Sound Transit July 1, 2016, ST3 Map detailed Sound Transit's Prop 1 plan for reducing the congestion.  The 11-station, 38-mile route bretween Lynnwood and Burien was costed at $812--$869M (2014$) and projected to have 15,000—18,000 riders when completed in 2024. The ST3 plan details were included as “Key Attributes”.

 

The recent May 8th video showed the Baseline Stride BRT Program had devolved into four projects costing $2,350 million to be completed in Q2 2029.  The1st project was a Bus Base North costing $499.5M starting construction this summer, with completion Q4 2027.  Despite the Key Attributes including the following as one of the 10 “Not Included” projects: 

 

Operations and maintenance facility not included

 

Sound Transit didn’t need a 120-capacity bus maintenance facility for the 48 Stride buses.  They certainly didn’t need to spend additional funds for battery powered buses requiring conductive charging along the route, whose design was started in Q1-2024.

 

The I-405 BRT portions S1&S2 cost $1,269M with the following July 2023 announcement as part of the cost: 

 

                 Sound Transit board members approved a $287 million deal Thursday to                       fund a unique triple-decker interchange on I-405 

 
 Yet the I-405/NE 85^th In-Line Freeway Station has no parking within walking distance for access.   Another concern was the following:

 

Relies on WSDOT to maintain adequate speed and reliability of I-405 express toll lane system

 

The problem being the WSDOT I-405 express toll lane system requires 2-person carpools transfer to GP lanes, or like SOV drivers, pay HOT fees to travel on one of two HOV lanes.   The increased GP lane congestion increases the number of those willing to pay the fees. 

 

During peak commute, the large numbers of those willing to pay the WSDOT's maximum $15 fee will increase HOV travel times for those paying the fees and those riding BRT buses. Especially between Bellevue and Renton (and presumably to Burien) where the WSDOT 2-lane HOT lanes will leave only 2 GP lanes. 

 

During peak commute,  the increased HOT travel times will dwarf any savings from Sound Transit improving access to stations as well as those paying the fees. During off peak commutes, imposing HOT on the 2^nd lane wastes the lane's capacity.

The bottom line is, Sound Transit is funding a bus base north that was precluded in ST3 Key Attributes. That until WSDOT decides to impose whatever HOT fee is needed to limit traffic on a single HOV lane, the benefits from Stride I-405 BRT are limited at best.