Study finds arena would have modest impact on SoDo traffic

SEATTLE — A new basketball arena would have a modest impact on traffic in the SoDo area, a study released by the Seattle Department of Transportation says.

The study, by Parametrix, was released on Wednesday.  See the complete study here.

The study says that on days with an event at the new arena, there would be about 6,000 additional vehicles in the area, which the study said is "well within the existing parking, traffic, and transit capacity" there. The number of days each year with events drawing more than 40,000 people would increase from three to nine on weeknights and from 22 to 33 on weekends, assuming attendence at Mariners games of 30,000 on weeknights and 37,000 on weekends.

"The vast majority of events at the new arena would not occur on the same day as other events at Safeco Field or CenturyLink Field. The majority of events occurring on the same day would not occur at the same time, even with the addition of the new arena. The probability of same-day events is slightly higher in the Spring when the Mariners and Sounders FC seasons are starting and NHL and/or NBA teams could be in the playoffs," the study said.

The study was paid for by Chris Hansen, the developer who wants to build an 18,000-seat facility that could house an NBA and an NHL franchise near where the Mariners and Seahawks play.

John Persak, a representative for ILWU Local 19, the local Longshoremen union, said Wednesday evening that the study was "inadequate and woefully incomplete."

"A comprehensive study would have considered the impacts of traffic  on the viability of the Port of Seattle," Persak said in a statement. "The study only seems to be concerned about the impact that the additional traffic would have on the other sports venues in Sodo, but it gives little attention to the added pressure it puts on port and industrial users in the area."

The study found that a total of 20,100 existing, planned, and dedicated arena parking spaces would be available within a 15-minute walk from the proposed arena's location and Safeco Field, and that 19,000 would be needed to handle parking for a sold-out Mariner's game and an event at the arena.

The study noted that events at the arena -- which would start at 7 or 7:30 p.m. -- would not coincide with normal daytime operations at the Port of Seattle, which closes operations at 4:30 p.m.

And it said most of the traffic for arena events would be on First Avenue and roads to the east, while freight operations to and from the port would be on roads west of First Avenue South.

The Port of Seattle and the Mariners both say a new stadium could hurt businesses in the area.

Last week, the city, King County and Hansen announced a memorandum of understanding laying out the financial responsibilities for the proposed venue. The agreement now goes before the Seattle City Council and King County Council for review.

A new local poll out Wednesday indicates though most voters approve of an arena, the majority don't want any public funds used for the project. Whether the city issuing $120 million in bonds is considered public money is not clear in the poll, but voters may still to be convinced an arena deal is worth it, Francis said.

Nearly half of poll respondents said SoDo was a good location for an arena. The same number of people said paying to improve the roads in the area was also worth it.