Tokyo building $26b toll expwys much in tunnel

Tokyo's Metropolitan Expressway Public Corp (MEPC) has 5 toll expressways under construction within the Japanese capital totalling 54.4km and costing $26b. Another 24km of inner city expwys to cost approx $10b are going through the permits process to add to the 248km in operation, and over 6 more routes of more than 100km length are under study. One major elevated interchange is also being rebuilt to reduce congestion from weaving. And MEPC has a seismic strengthening program to improve earthquake resistance to existing structures. Other state corporations are building tollway facilities peripheral to Tokyo in what is in total perhaps the world's most extensive and elaborate contemporary urban highway construction program.

MEPC's operating toll expwy network is 4/5 elevated and 1/5 underground, but the new construction is 1/3 underground and 2/3 elevated. Projects under way are:

(1) Shinjuku section of the Central Circular route, the most expensive current construction project at $9b, 11km in length and almost entirely underground, it is being constructed underneath existing Metro Road #6, an overcrowded surface arterial. This construction is located about 8km out from the 25 year old Inner Circular expressway, a complex tight, often double-deck elevated structure in the center of Tokyo.

(2) Oji section of the Central Circular is almost contiguous with the Shinjuku — a 7km new roadway costing $4b that has one underground and two elevated sections. It extends counter-clockwise from a portion of the Central Circular opened in 1987.

(3) Section 5 of the Bayshore Expwy is the longest bit of construction work presently going on consisting of 14.6km of new roadway costing $4.4b. Entirely elevated it extends southward toward Yokohama the recently opened Bayshore route that was built on reclaimed harbor land and with a spectacular series of long bridges and immersed tunnels to cross shipping channels.

(4) Trans-Kawasaki: The beginning of a third circular route is a $4.8b 7.9km long road that heads west from the portals of the soon-to-open Trans-Tokyo Bay tunnel along the southern bank of the Tamagawa river. Parts of this are underground and other parts elevated, some double-deck.

(5) the Omiya route: a northern radial 13.8km and $4b in cost has a 3km tunnel with the rest elevated on huge steel Y-sections

Individual underground highway projects somewhat similar to those in Tokyo are currently under construction in Boston MA, Melbourne Australia, Lyon France and Stockholm Sweden but none we know have so many complex projects going at once. Hong Kong has 8 highway toll tunnels and a ninth under construction.

These new Tokyo expwys are being built with 3.5m lanes compared to earlier 3.25m, mostly 4 lanes, a few 6, and accept trucks up to 25t weight — lighter shorter trucks than are common in Europe and N. America. MEPC uses a ticket toll system with tolls taken exclusively on ramps with use of coupons, coin machines and attendants. There is no electronic tolling yet. Revenues are quite similar in total to those collected in the New York/NJ area, $2.6b last year. Tolls for cars average 35c/km and about 1.2m vehicles enter the system each day.

MEPC maintains traffic flows on its mainline system with comprehensive video surveillance and a management center that controls ramp meters. It regularly closes some entry ramps entirely for periods of 20 to 30 minutes in rush hours to avert mainline stop&go. It has some of the world's fanciest variable message signs and other traveller information services. (Contact Mariko Takahashi MEPC fax 81 3 3503 1806)