The Seattle Times Editorial Board questions the value of the traffic study issued by the developer of the proposed Seattle basketball arena.

THE traffic “study” for the proposed basketball arena in Seattle’s Sodo District was sure done quickly. Investor Chris Hansen is in a sweat to let his deal flow to its desired conclusion before anyone sandbags it.

His spokesman said he had no control over the study; the city required it and he paid the $70,000 for it.

The capsule summary is that the traffic will be fine.

Actually the study does not quite say that. It says the traffic will be bearable most of the time, providing fans are willing to park as far away as the western edge of Interstate 5 and walk through Sodo, and providing the Mariners aren’t winning big. If the baseball team has a big season, it will conflict with basketball, and there will be days of traffic hell.

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The study says this can be handled with “added parking supplies,” “future road improvements” and “a major expansion of Link light rail.” That’s not quite saying traffic will be fine.

The study didn’t look at how traffic behaves in the hours before a game, though critics said the buildup begins hours earlier. As for the effect of future stadium traffic on the trucks going from the Port of Seattle’s container terminals, the study said it “would be minimal.”

Maybe it would be, at first. But the Port wants to grow. Over the next 10, 20 or 50 years, container volumes are bound to increase — and they will conflict with basketball traffic.

Probably they will conflict with baseball and football traffic whether the new arena is built or not. A basketball arena will make congestion worse, hastening the day when Seattle maxes out on waterborne trade.

That is not a limit Seattle ought to place on itself.