As Sound Transit steps up planning for I-405 BRT, WSDOT is preparing to extend managed HOT lanes from Bellevue south to Renton. Meanwhile, a political consensus in favor of tolling has solidified. After an unsteady start, managed lanes have grown more popular with the public. Eastside cities are recognizing both the benefits in managing traffic and the need for toll revenue to fund future capacity expansion. Eastside cities have joined with transit agencies and local employers to lobby for continued tolling and an expansion of toll lanes at the north end.

Current and planned express toll lanes on I-405 and SR 167 (image: WSDOT)

The first HOT lanes (high-occupancy toll) in the region opened on SR 167 in 2008. In 2015, another 15 miles of HOT lanes opened on I-405 between Bellevue and Lynnwood. Throughput on the lanes is maximized with a combination of free HOV-3 and tolling for other vehicles. The former HOV-2 lanes were badly congested as too many vehicles qualified to use the lane, but HOV-3 alone would leave the lanes under-used. Tolling balances traffic by allowing just enough other cars into the HOT lane so it is used efficiently, but not overwhelmed. Raising the HOV limit to three occupants at peak hours, however, did make the lanes unpopular with former two-person carpoolers.

In Renton, construction is underway on HOV-to-HOV ramps between I-405 and SR 167. Those will open for traffic in 2019, enabling higher occupancy vehicles to avoid the weave across several lanes of general purpose traffic. Construction then begins on widening I-405 to create two HOT lanes in each direction between Bellevue and SR 167. A fifth of the $1.175 billion cost is funded from future tolls. Completion of the Bellevue-Renton HOT lanes in 2024 will enable Sound Transit to operate BRT on this corridor.

Between Bothell and Lynnwood, the highway narrows to just one HOT lane and two general purpose lanes in each direction. Demand for the HOT lanes is so high that they often fail to clear even with tolls at the statutory maximum of $10. Toll revenues funded a shoulder lane between SR 527 and I-5 that opened in April 2017. That significantly improved operations in the northbound direction, increasing vehicle throughput in the general-purpose lanes and reducing toll rates. The cost was a low $11 million. Future planned improvements in the I-405 Master Plan have higher price tags and currently lack state funding, but could be paid for by future tolling.

It is against this background that the continued operation of managed lanes is being debated. All the major Eastside cities, the transit agencies on the corridor, and many large employers, have joined in lobbying the Legislature. They seek continued tolling along the corridor and an expansion of the HOT lanes north of Bothell. Two recent joint letters lay out the interests of local stakeholders.

Transit providers joined in one letter with King and Snohomish Counties and several of the major cities on I-405 (Bellevue, Kirkland, Renton). The letter describes at some length the improvements in traffic operations in the corridor from tolling, and the need for tolling to operate BRT. Signatories emphasize their continued support of the I-405 Corridor Program and asks that the Legislature extend and establish authorizations for operation of tolling along I-405. Because operation of express toll lanes offers the most effective throughput for all highway users, they support toll operations to Renton with the added HOT lane, adding a second express toll lane in both directions through the 405/522 interchange and north to SR 527; and use of managed lanes to serve Sound Transit BRT.

A second letter is from the North I-405 Stakeholder Group. The group comprises nine cities (including every city on the highway from Bellevue to I-5) and several local legislators along with major employers in the Bothell area. They are seeking an acceleration of WSDOT’s construction of a second HOT lane in each direction from SR 522 to SR 527. Pay-as-you-go toll revenues can fund an added southbound HOT lane by 2028 and northbound by 2033. WSDOT could feasibly deliver both by 2024 if funding were available. The Stakeholder group emphasizes the demand to accelerate delivery of the extra HOT lanes so that they are open before BRT operations commence in 2024.

The miss on speed standards has been an easy talking point for tolling opponents, but stakeholders in the corridor recognize they need tolling revenues to fund a second HOT lane in that area. A reversion to the failed HOV-2 lanes would mean losing the traffic management benefits of tolling and no more capacity. Even as some legislators make noises about the miss on the speed standard, the Legislature funded preliminary engineering to expand the lanes north of SR 522, and the Renton-Bellevue work is funded and proceeding without interference. Legislators from outside the region are unlikely to support statewide taxes to replace foregone toll revenues. Bonding of toll revenues could accelerate work on the Bothell lanes if legislators commit to tolling for the duration of the bonds.

HOT lanes between Bellevue and Lynnwood are handily meeting speed performance standards except soutbound into Bothell. (image: WSDOT)

The lanes face one more hurdle in the Legislature. The enabling legislation specified two performance standards to be met to continue operations. One, generating enough revenue to cover operating costs, was easily exceeded. The second, maintaining vehicle speeds in the lanes above 45 mph during 90% of peak hours, was easily met in the dual HOT lane section, but has been challenged by inadequate capacity southbound between I-5 and SR 522. In the southbound single-lane section where demand is too high for a single tolled lane, the speed standard is met just 63% of the time.

Improvements at the north end of the corridor would improve transit performance too by improving speeds and allowing greater transit use of the HOT lanes. Adding a second HOT lane would allow direct access to the HOT lanes at SR 522 and SR 527, greatly reducing the time Sound Transit’s BRT operates in general purpose lanes.

Peter Rogoff made explicit, at the October meeting of the I-405 Executive Advisory Group, how legislators would prevent BRT from operating if they undermined the managed lane system. “If the traffic’s not going to move, there will be no rapid in bus rapid transit, there will be no high in high capacity transit, and we would have to completely rethink the investment as a Board. So I hope to be able to communicate that to those that want to revisit the regime at this point because frankly our whole plans for the I-405 BRT are premised on the facts that the lane has got to move.”

The theoretical benefits of tolling have been validated by two years of experience. Legislators took some lumps from constituents as tolling was introduced, and WSDOT made some significant concessions including dropping tolls on nights and weekends. But the experiment has largely worked as designed. With high travel demand in the corridor powered by the boom in residential growth in South Snohomish County, the north end of I-405 remains very congested. Both transit users and the drivers paying up to $10 each way will benefit from expansion of the HOT lane system.