We’re back at the Alaskan Way Viaduct project HQ in the Wells Fargo building downtown for another of what’s become nearly weekly briefings on more data from ongoing analysis of the options under study for replacement of the Viaduct’s “Central Waterfront” section. A final scenario is supposed to be settled on by year’s end. The data that’s coming out today involves analysis of “open space” created by the various scenarios, and economic impacts. We’re reviewing the material handed out in advance of the briefing – the “open space” information includes significant analysis of the “integrated elevated” option, Scenario E (above), that’s gained a lot of buzz (in no small part because of support from State House Speaker Frank Chopp) – the handout says that option “is the least desirable option from an urban design and open space standpoint and, in some respects, is worse than the existing Viaduct. While (it) has the most open space overall, it provides a lower quality of public space and compromises the historic identity of the waterfront and access to it from the downtown.” That’s just part of what we’ll hear about shortly, when state, city and county reps join us media types for the briefing. We’ll add any major points as it continues, as well as links to these presentations when they are up on the Viaduct project website (alaskanwayviaduct.org) – meantime, here’s the “open space” presentation, from the media disc that’s just been provided, and here’s the “economics” presentation. All this comes out in advance of the Stakeholders Advisory Committee meeting later today (4 pm, City Hall). UPDATE: The presentations are all on the Viaduct website now too – under Dec. 4 meeting materials – find them here. Here’s the news release summarizing what’s being presented today:

SEATTLE – WSDOT, King County , and the City of Seattle released information on the final set of evaluation results for the eight scenarios under consideration for the Alaskan Way Viaduct and Seawall along the central waterfront. The newly-released results factor how each scenario and its construction might affect the local and regional economy. The agencies will use this information to create two to three hybrid scenarios which they will announce a week from today. A final recommendation is expected by the end of the year from Governor Gregoire, King County Executive Ron Sims, and Seattle Mayor Greg Nickels.

The analysis conducted by EcoNorthwest included case studies from other regions, interviews with local businesses, and economic modeling.

Results released today showed no significant economic differences among the scenarios after construction. All scenarios replace some of the viaduct’s capacity and where travel times increase, the number of trips affected represents a small percent of the total regional trips. The economic model found that industries such as professional services and tourism are unlikely to move outside the four-county region due to the viaduct scenarios.

Land value increases ranged from $50 to $250 million near the Seattle waterfront, depending on the final scenario chosen. The increase in open space with some scenarios also increased the development potential along that corridor.

The biggest differences were due to permanent reductions of on-street parking and increases in some travel times for several scenarios. This is felt mostly by trips from neighborhoods north and south of downtown Seattle that use SR 99 as a through route. While increased travel times result in higher costs for businesses, the economic analysis predicts this will result in less than one percent loss of jobs or economic output.

The larger issue was business disruptions during construction when access and amenities are restricted. The report showed that construction disruptions are not substantial enough to threaten regional economic vitality, but local businesses will be affected.

“Construction on the central waterfront is going to be challenging, but we’re adding additional hours of transit service in key corridors to ensure that residents have as many options as possible to get around,” said Harold Taniguchi, Director of King County DOT.”

Freight trucks and others going from Ballard to points south of downtown will face increases in travel times during intense construction periods, although through trips on SR 99 account for a small percentage of all trips within the study area. Major construction on the central waterfront is expected to last approximately four to six years, depending on the scenario chosen. Those businesses near the waterfront will face greater challenges getting customers around the construction zone during major construction.

“We know how important our waterfront businesses are to us and the local economy, and we are committed to reducing construction time and mitigating disruption as we prepare to take down this vulnerable structure,” said Grace Crunican, SDOT Director. “The good news is that when construction is complete, we’ll have an improved waterfront that will benefit those businesses.”

A report by ROMA released today found that all scenarios increased open space on the downtown waterfront. The public promenade would increase anywhere from 20 to 105 feet in width. In addition, a new 12 to 20 foot sidewalk would be provided on the east side of Alaskan Way . Only the integrated elevated structure does not provide the optimal promenade width of 70 feet of promenade space on the street level.

“We’re pleased that all of the options provide additional open space for public uses along the central waterfront compared to today’s conditions” said Paula Hammond, Secretary of Transportation.

Information on noise levels, traffic safety, and bicycle and pedestrian connections was also shared today with the Stakeholder Advisory Committee.