Although Seattle Mayor Mike McGinn has urged a public vote as soon as May on funding for a sea-wall replacement, the City Council on Monday began looking at other options.

One approach would be for the City Council to issue the bonds, and forgo a ballot measure. But there isn't enough cash coming in to support such bonds, said Ben Noble, of council staff. The solution? If the city increased parking taxes and imposed a $20 car-tab fee, that might support the bond, Noble explained, citing one scenario.

Councilmember Tom Rasmussen, chairman of the council's Special Committee on the Viaduct and Seawall Replacement Project, wants to look further. Voter-approved bond measures need a supermajority, he points out.

And in a troubled economy, "I would be concerned about making a 60 percent vote; that will be very tight," he said.

The old sea wall is deteriorating and anchored in weak soil. McGinn wants to accelerate sea-wall replacement to 2014, from the state's original 2016 timeline.

But Rasmussen said a vote -- if it happens -- could wait until November, since the sea wall won't need a big cash flow until 2012.

Meanwhile Councilmemember Nick Licata suggests pushing harder with the Army Corps of Engineers to declare sea-wall protection to be in the national interest, and to provide federal grants, even if that means losing two years.

Licata and others point out a downside to boosting on car-tab fees and the parking tax. Those are the potential sources for millions in bike and pedestrian projects the city promised a few years ago and isn't fully funding. Beyond that, the city has over $1 billion in unfunded capital proposals: a broadband network, Harbor Patrol station, Magnolia Bridge, Rainier Beach community center, King Street Station restoration, to name a few.

Earlier this month, in a letter to the council, McGinn urged members to take the sea-wall funding to voters, so the city would have a freer hand to fund other wants and needs without direct voter approval.