A Baltimore delegate plans to introduce legislation to create an authority to oversee a new stream of school construction money that the city would get under a plan envisioned by schools CEO Andrés Alonso.

Del. Keiffer J. Mitchell Jr. said his bill would trigger a referendum in which city voters would be asked to create the Baltimore City Schools Construction Authority. If voters approved, the authority would administer a lump sum that the state would provide to the city each year to meet school construction needs.

Mitchell, a Democrat, said the new agency could issue school construction bonds to leverage the money it would get from the state and to increase the amount available to replace and renovate aging city school buildings.

Alonso has said he would like to borrow $1.2 billion to pay for an overhaul of the city's school buildings. That would be six times the school system's current bonding authority. As part of that idea, Alonso is asking the state to provide a guaranteed revenue flow of $32 million a year to apply to construction projects.

Mayor Stephanie Rawlings-Blake, who has proposed raising the city's bottle tax to help pay for school repairs, said she has not decided whether to back Alonso's plan. And she said "it's too early to say" whether she would support Mitchell's proposal, though she said she is "intrigued by the notion."

Mitchell, a former city councilman and mayoral candidate, said he sees his bill as a companion to a separate measure, sponsored by Del. Keith E. Haynes and Sen. Verna Jones-Rodwell, that would convert the current system for funding city school construction from project-by-project financing to a block grant. Both are Baltimore Democrats.

Mitchell said the ballot question envisioned in his bill would set up a system in which the mayor would name the majority of the authority's seven-person board, which would also include the schools CEO and two members of the school board.

"There is at least some accountability because it is in the mayor's office," Mitchell said.

Mitchell said his bill does not call for a state role on the authority board but indicated he would consider such an amendment.

But Mitchell said it makes sense to give the mayor ultimate responsibility for how the grant is administered.

"The city owns the schools, the city owns the land, the city's on the hook," he said.

Baltimore Sun reporter Julie Scharper contributed to this article.