Cover slide of the Sodo arena presentation by Chris Hansen’s team to the city council Tuesday.

Nearly four years after after he made a five-year commitment with the city to build an arena in Sodo and find a team to occupy it, developer Chris Hansen finally scored. He won a city council subcommittee vote 4-1 Tuesday afternoon to advance his project to a full council vote May 2.

Enhanced by a PowerPoint presentation from Hansen’s team with a dazzling array of previously undisclosed public amenities as well as capital improvements such as a parking garage and a pedestrian overpass, all funded by Hansen, the decision to advance the vacation of a one-block stretch of Occidental Street was supported by transportation committee chair Mike O’Brien, along with members Tim Burgess, Bruce Harrell and Rob Johnson.

Hansen’s PP presentation can be found here.

Sally Bagshaw was the lone dissenter, saying vacating Occidental was “a seriously bad idea.” She needs all of the remaining council members — Lisa Herbold, Kshama Sawant, Debora Juarez and Lorena Gonzalez — to agree with her May 2 to stop the process.

Perhaps the most unexpected bit of information came from Burgess, who was a signatory to the 2012 memorandum of understanding among Hansen, the city and King County that provided the framework of the arena deal.

Burgess explained the council regularly considers street vacations from developers whose proposals claim a public good that requires council verification and approval. Then he flashed a slide of the Seattle map.

The Port of Seattle, which has been the most vigorous opponent of the Occidental vacation, claiming that a third sports venue in Sodo would seriously bind freight traffic and cost many jobs, had 32 approved requests from the council for street vacations.

The drop-the-mic moment passed quietly in the chamber, because many of the pro-and-con speakers in the earlier public-comment period had departed. But there was no mistaking that some wind escaped the port’s sails.

The 32 requests granted don’t reflect on the arguments about Occidental, but they do suggest that the port’s long-held belief that the city has been dismissive of port positions was a tad overwrought.

Another primary opponent, the Mariners, were similarly granted a vacation in 1996 for the same street, Occidental, a little farther north, to make room for Safeco Field.

Nearly as much a milestone in the process was a vote on nine amendments to the Seattle Department of Transportation’s conditions for approving the vacation. Council members and staff, hearing from opponents recently as the vote approached, tightened and clarified language and responsibilities in the documents. Bagshaw abstained, while the other four council members voted to pass on the amendments to the full council.

Perhaps the most important among them was an amendment to strengthen the event-scheduling requirements to reduce the number of days with multiple large crowds. The Mariners, as well as the Seahawks, wrote lengthy, detailed complaints to the council saying that they had no substantive meetings with Hansen’s company, ArenaCo, prior to the Tuesday vote to advance the vacation.

Apparently some heavy, hasty negotiations among all parties, including the Sounders, took place in the last several days, because Burgess remarked that the meetings “were the first in a long while.”

One item that will draw further scrutiny leading up to the May 2 vote is this stipulation:

No arena event on a non-holiday weekday or weeknight may be scheduled to begin or end within one hour of the scheduled start or end time of any scheduled event at Safeco Field, or CenturyLink Field, or both, if 1) the reasonably anticipated attendance at the arena and one or more of those fields is more than 45,000 attendees, or 2) there would otherwise be three scheduled events starting or ending within an hour of each other at the Arena, Safeco or Century Link.

Harrell said that one-hour rule was a “non-starter” with the Seahawks, who called him and apparently insisted on more time between events. The amendment passed, with the understanding that the next two weeks would provide time for further changes.

Before the vote, O’Brien signaled some optimism, saying, “I believe there’s a path where this arena could be built. We get significant benefits and would continue to make the other investments where we continue to make our port and maritime industrial sector a thriving sector.”

Hansen agreed to pay for a pedestrian bridge ($15 million to $18 million) along Holgate Street to keep fans away from the nine railroad tracks near the proposed arena in Sodo.