Seattle's narrow north to south geography will create a major challenge in keeping traffic flowing when the Alaskan Way Viaduct is torn down in 2012.

"It's an hour glass. A lot of people are pushed through it," said Ron Pannanen, project director for the viaduct, with the Washington State Department Transportation.

Pannanen made the comments during a Ballard Rotary Club luncheon. He said the state is looking at traffic solutions from Interstate 5 to the waterfront once the viaduct is torn down. The viaduct was built in the 1950s and was damaged during the Nisqually earthquake in 2001.

An average of 400,000 trips are made through downtown each day. Those trips bring carry 500,000 people, according to Pannanen.

Viaduct and I-5 traffic has doubled in 33 years.

During weekdays, well over 100,000 cars travel northbound and southbound on the viaduct.

Transit and surface options are all part of the discussion between city and state agencies to divert traffic.

Some of the strategies according to the Washington State Department of Transportation website include: message and travel time signs on I-5 to maximize safety and traffic flow; funding SR 519 Phase II to improve freight connections from I-5 and I-90; widening the Spokane Street Viaduct to include a Fourth Avenue loop ramp for West Seattle drivers; more bus service in the West Seattle, Ballard/Uptown and Aurora Avenue corridors; upgraded traffic signals; and education on travel alternatives and incentives to use car pools, transit and vanpool programs.

"All alternatives are on the table," said David Dye, deputy secretary for the Washington State Department of Transportation.

Dye said the seawall from pier 48 to pier 70 at Broad Street is in poor condition. It is weakest in the central waterfront to the aquarium where the soil can liquefy in an earthquake.

"If the seawall fails, the viaduct is jeopardized," said Dye.

The state has shored up four columns from Columbia Street to Yesler Way with 80 cubic yards of concrete in the foundations. The columns have settled 5 inches since the earthquake.

As part of the department of transportation's $915 million "Moving Forward Projects," involving the viaduct, a number of things are planned or in the works.

Electrical lines from South Massachusetts to King Street are being relocated and a $20 million contract bid on the work is going out later this year.

Fire and safety systems in the Battery Street Tunnel are being upgraded. The viaduct will be stabilized from Lenora Street to the tunnel.

From south Holgate to south King Street the viaduct will be replaced. Transit enhancements and other capital improvements are being planned.

One of the questions asked at the Rotary gathering was about a possible retrofitting of the viaduct.

Dye said it does not seem to be an option because of the overall condition of the structure. The decks of the bridge and the beams, which are cracked, all need repair.

Dye pointed out, there is no measurable benefit to retrofitting the viaduct. It would only mean "chasing problems" from one spot on the bridge to another.

A Stakeholder Advisory Committee continued a series of meetings on April 24. The group of 30 people has members from community organizations, business, neighborhood, freight, commuter, environmental and other interests. The committee is lead by the Washington State Department of Transportation, King County Department of Transportation and Seattle Department of Transportation.

The next Stakeholder Advisory Committee meeting is May 8 at the Seattle Center's Fidalgo Room from 3:30-5:30 p.m. These meetings are open to the public. See the website below for a complete list of stakeholder meetings. Upcoming Central Waterfront Open House public meetings are scheduled. On May 15, from 5:30-7:30, a meeting is at Adams Elementary School, 6110 28th Ave. N.W. Other meetings include: May 8, Seattle Center Northwest Rooms, Lopez room, 5:30-7:30; May 13, Madison Middle School, 3429 45th Ave., 5:30-7:30; Visit http://www.wsdot.wa.gov/projects/viaduct or e-mail viaduct@wsdot.wa.gov. The program information line is 1-888-AMV-LINE. The mailing address is: Alaskan Way Viaduct and Seawall Replacement Program, c/o Washington State Department of Transportation, 999 Third Ave., Suite 2424, Seattle, WA 98104.