Mayor Mitch Landrieu isn’t giving up on his effort to install Cedric Grant, one of his top deputies, as the new executive director of the New Orleans Sewerage & Water Board, despite a state Ethics Board decision saying the move would be illegal.

The Louisiana Board of Ethics last month narrowly voted to advise the Water Board that Grant could not take the job because a state law bars members of public boards from stepping down and then taking a job with that same board within a two-year period.

But a bill pending in the Legislature would give Grant an exemption from the law, clearing a path for one of Landrieu’s top lieutenants to take charge at one of the city’s biggest agencies.

Such exemptions are relatively routine, and the one Landrieu is seeking for Grant passed out of the Senate and Governmental Affairs Committee on Wednesday by a 6-to-1 vote after just a few minutes of discussion.

Sen. Ed Murray, D-New Orleans, cast the lone vote against the measure. Murray said he has nothing against Grant but typically votes against such exemptions, arguing that it makes no sense to have an ethics code if the Legislature is going to continually allow individuals a pass.

“I just don’t think it’s the right thing to do,” Murray said. “We have an ethics code for a reason.”

Sen. J.P. Morrell, another New Orleans senator who co-sponsored the bill, backed the mayor’s argument, noting that Grant — Landrieu’s deputy mayor for facilities and infrastructure — served on the Sewerage & Water Board only as a stand-in for the mayor, not as an independent or permanent member. The mayor automatically serves as the board’s president but can designate someone to attend meetings in his place, and Grant attended most of the board’s meetings over the past three years.

“I think the individual in question is more than qualified for the job,” Morrell said, adding that the Ethics Board’s advisory opinion might have an undue chilling effect on future appointments were Grant not to get the position.

Landrieu’s push for the exemption this week came with relatively little notice. After the Ethics Board’s advisory opinion came out, the Mayor’s Office said only that it was considering its options.

The Senate committee fashioned the exemption for Grant out of an unrelated bill filed months ago, inserting language just before the vote that would waive the relevant portion of the ethics code for mayoral designees in any municipality with a population of 300,000 or more. No one from the Mayor’s Office spoke before the committee voted.

In an email, Landrieu spokesman Tyler Gamble said the exemption would only clarify the law, passed in 2011, that allowed the mayor to appoint a designee for board meetings in the first place. “It was never our intent that this local bill would have the effect of making his staff designee a full-fledged, independent member of the board,” he said.

The next public update on Grant’s appointment could come Friday morning, when the Sewerage & Water Board’s Executive Committee is scheduled to hold its regular monthly meeting.

The board is in the midst of a major transition. A bill that passed the Legislature last year restructured the board’s membership, cutting the number of directors and for the first time setting professional qualifications as a prerequisite for most board seats. Meanwhile, the agency is in the midst of a major effort to replace decrepit sewer and water pipes, as well as an aging power plant.

Last month, Landrieu nominated eight candidates — including three holdovers from the sitting board — to serve four-year terms. The City Council is slated to vote on their appointments May 22.