This post has been updated.

The city council just sent a sternly worded letter to Mayor Mike McGinn, questioning his proposal to send a $241 million bond measure to voters in May to pay for replacing the deteriorating downtown waterfront seawall.

As first reported on PubliCola last week, the city council was blindsided by McGinn's surprise proposal, which he announced without giving any prior notice to most council members. (The council has the ultimate authority to put any bonding measure on the ballot).

The council's letter, which every council member except Mike O'Brien (a fellow tunnel opponent and longtime ally of McGinn's) signed, calls for a "comprehensive project plan" for replacing the Alaskan Way Viaduct and the seawall, and notes that the city's department of transportation (SDOT) has already put out a call for design teams to replace the seawall, with construction to be completed by 2015. (McGinn's plan would move that date up a year).

"Have you received recent information that causes you to recommend modifications to the sewall replacement schedule presented by SDOT? If so, please provide Council with that information," the letter says.

Council transportation committee chair Tom Rasmussen, who drafted the letter last week along with freshman council member Sally Bagshaw, says he doesn't understand why the city would want to "take this question to the voters in May, at a cost of a million dollars [the cost of running a special election], and fund it with property tax dollars? The project is already underway. We need to think this through and stay on schedule."

"He has to provide answers to these questions before I would vote yes or no," Rasmussen says. "He certainly doesn’t have a 'yes' vote from me at this point."

The letter also points out that the council just requested an analysis of three potential funding sources—an increase in the parking tax, a local tax on businesses around the viaduct, and a transportation benefit district. "We are open to considering other ideas, such as a bond issue or levy, but the Council feels that it is very important that we have a comprehensive plan so that the public and elected decision makers are fully informed about what to expect over time."

Finally, the letter points out that off-cycle elections (i.e. a special election in May) are expensive, and that there are other city programs and projects that need funding. "The City has asked its citizens for a great deal these past few years and the people of Seattle have been very generous. Voters expect and deserve predictability and a sound financial strategy before we ask again."

O'Brien, the only council member who didn't sign the letter, says he believes the seawall should be separated from the question of viaduct replacement. "There's a series of big questions that need to be answered on the tunnel before it moves forward, and I don’t think the seawall project should be held up in that debate." And he worries that the push by the rest of the council for a "comprehensive funding plan" is code for building the seawall as part of viaduct replacement; "I would not be supportive of going to voters with a billion-dollar package with a bunch of different things that some people want and some people don’t," he says.

In an email, McGinn's spokesman Aaron Pickus said, "The mayor will be speaking with councilmembers on Monday and looks forward to answering their questions and engaging on this topic then."