TACOMA NARROWS WA:New investor toll suspension bridge likely

After a long period of uncertainty and little movement United Infrastructure’s suspension bridge at the Tacoma Narrows in Washington state seems on the way to construction. Earlier this year the WA state DOT selected the second suspension bridge as the preliminary preferred alternative for solving congestion problems on WA-16 which is the only real fixed crossing into the greater Seattle metro area from the Kitsap or Olympic peninsula (pop 350k) immediately across the Puget Sound.

The twinning project has to complete the environmental impact process and an advisory popular ballot in November. But signs are there is clear majority support for the project. Surveys shows majority support for construction of the bridge, some very strong majorities. 47% say it should be funded with tolls to 25% who favor tax money and 18% who want some mix of tolls and taxes. $3 has been publicized as the proposed round-trip toll and this is considered acceptable by 64%.

Support for enhancing capacity coexists with a great deal of anti-growth sentiment and even fatalism about traffic.

The current Tacoma Narrows bridge carries over 80k-90k veh/weekday on 4 substandard 3m (10’) lanes with no median or shoulders. Backups and slow moving traffic are 3 hrs eastward mornings and 3 to 4 hrs westward afternoons. The first Tacoma Narrows bridge which opened in 1940 was famous for its rolling movement in light winds and was nicknamed “Galloping Girtie”. Four months after it was opened however the joke ended when in just 40mph winds it was torn to destruction, everything but the towers falling into the waters of the Sound. A famous film clip of its end was shot. Wind effects in suspension bridges were studied intensively after the collapse of the first Tacoma and many existing bridges strengthened. The present bridge was opened in 1950.

Keewit slinks away

United Infrastructure submitted its proposal to design, finance, build and operate a to-be-selected enhancement of WA-16 across the Tacoma Narrows in 1994 and was selected for a toll franchise. It was one of a dozen investor road proposals which included plans for a metropolitan-wide network of HOT lanes and several turnpikes. They were submitted under a 1994 Public Private Initiatives in Transp law which had been widely supported in the state legislature. But the next year a new generation of politicians gutted the law and aborted most of the projects in a storm of anti-toll and anti-highway political demagoguery from the right (“Wee alreddy paid fur it, ain’t we?” stuff) plus enviro/NIMBY protests. The only major project to survive the fiasco was the WA-16/Tacoma Narrows project. United Infrastructure at the time was a joint venture of Bechtel and Keewit. UIC based in Chicago was run by Gerry Pfeffer of Keewit, who also was the major figure in Calif Private Transp Co which developed 91-Express.

Keewit dropped out of UIC without announcement last year and the Chicago office closed. It is now run as a Bechtel subsidiary out of its San Francisco offices but its major operation is in Tacoma WA. UIC was quite advanced in negotiating a franchise late 1995 when the government bailed out. Instead it said it would use taxpayers money on the Tacoma Narrows project to advance the selection and design process. UIC got contracts worth $7m to manage the project selection and design process, obtain the permits and conduct the public involvement.

Hot air balloons & solar powered bathtubs

Tom Horkan, the UIC project manager, says the company still hopes to negotiate with the state a franchise to do the detailed design, construction and operation of the facility but that has to wait on completion of permitting and the popular ballot in Nov.

22 alternates were considered in the selection process including a direct bridge across the east Sound from the northern edge of the Seattle-Tacoma airport, enhanced ferries, rail, tidal flow reversible lanes, pricing, a tunnel... The US Govt required “No build” alternate was rejected in one sentence as “not meeting the primary objectives of improving personal and freight mobility and safety in the WA-16 corridor.” TSM/TDM, tidal flow, ferries etc didn’t hack it. Rail couldn’t get significant ridership and had no measureable impact on road traffic. A new direct bridge (WA-518 West) would be too long, too contentious and too expensive. It was a choice between doubledecking the existing bridge and a parallel bridge.

The parallel bridge is about the same cost ($300m) but it has many advantages. It can be built to higher seismic standards and 2 bridges offer greater earthquake security than one. It is less disruptive of traffic during construction. The new bridge with a main span of 853m (2800’) is being built wider 21m (69’) vs the old bridge’s 14m (46’) and stronger so a second deck can be installed in the future. The old bridge will be redecked and restriped to 3x3.6m (11’8”) lanes, one being designated HOV, plus shoulder from the existing 4-lanes. The existing bridge lanes begin to slow at 1.7k veh/lane/hr because of their substandard width and the generally tight conditions, engineers say, whereas full standard lanes should not do this until at least 2.1k to 2.2k veh/lane/hr. They put the capacity of 3-lanes one way of the new format as 6.4k to 6.8k veh/hr compared to the existing 2-lanes 3.8k veh/hr. On the new bridge there will be room for pedestrians and cyclists as well as full breakdown shoulders both sides. Left unspelled-out is the fact that there is probably room by reducing shoulders for a 7th reversible lane on the new bridge within that 21m cross-section.

The proposal also involces $100m of widening and other upgrades to 15km (9mi) of WA-16 on both sides of the Narrows. Much of it is presently only 4-lanes and it will be increased to 6-lanes and a couple of interchanges will be modernized.

Toll collection is proposed to be easterly only from a conventional barrier plaza on the north side with cash collection and electronic toll (ET). (Contacts Tom Horkan Tacoma Narrows Project Office and United Infrastructure 253 564 1616 and for a film clip of “Galloping Girtie” too www.wsdot.wa.gov/solve16/)

First new suspension for 34 yrs

No major new suspension span has been built in the US since the later of the two Delaware Memorial Bridges which link the Delaware and NJ turnpikes over the tidal Delaware River 45km downstream from Philadelphia. Opened in 1968, like its twin it has 4-lanes and is owned and operated by the Delaware River and Bay Authority, a bistate agency of the states of DE and NJ. The 8-lanes over the Delaware River carry an average daily traffic of 80k, less than half the per-lane load of the present Tacoma Narrows bridge. Another similar-sized suspension bridge (728m main span, but 4-lanes) is planned as a replacement for the older twin of two cantilever truss girder Carquinez bridges in the Bay area CA. The two Carquinez bridges carry c110k veh/day on 8-lanes of I-80 a major fwy between the San Fran Bay area and Sacramento the state capital, and the east via Salt Lake City, and Chicago ending in New York City. The Carquinez pair are owned and tolled (one way) by Caltrans. They are the locale for one of the US’s most protracted electornic toll conversions.