The current system, she said, stymies potential buyers and developers, and frustrates efforts to turn vacant lots into green spaces.
The bank would be allowed to dispose of land at reduced or nominal prices for "projects that demonstrate beneficial community impact," such as affordable housing and community gardens.
Rick Sauer, executive director of the Philadelphia Association of Community Development Corporations, said his group's members had been dealing with the bureaucratic tangle of city ownership for years.
"If you have a number of properties on one block you're trying to acquire, you can't just go to one place," he said. "If you had a single agency . . . that would really streamline the process and get that land back into productive use much quicker."
Vacant properties - whether empty lots or abandoned homes - long have been blamed for dragging down neighborhood property values, spreading blight and fostering crime.
About 40,000 parcels sit vacant in Philadelphia, concentrated in the poorest neighborhoods, including parts of Sánchez's Seventh District.
The city spends about $20 million a year to maintain its stable of vacant properties, and 17,000 private owners are delinquent on their taxes, owing $70 million, according to a 2010 consultant's report.
Councilman Bill Green, who cosponsored the Sánchez bill along with Bobby Henon, introduced companion legislation Thursday to address the city's delinquent tax collection system.
His bill would set up an installment payment plan for back taxes that would abate penalties and interest, but require foreclosure on owners who do not make the effort to get back on the tax rolls.
Mayor Nutter also established a Vacant Property Working Group that has been studying and working on the problem of empty parcels for more than a year.
The group has worked to boost code enforcement and created a master list of city-owned properties, now available online. The Department of Licenses and Inspections recently won a national magazine award for its vacant land management strategy.
The mayor also is expected soon to release his "front door" strategy, setting up the Philadelphia Redevelopment Authority as lead agency for the disposition of properties.
The working group, to which Sánchez was a recent addition, is in the final stages of drafting a policy for disposing of properties.
The land bank, which would be governed by a seven-member board appointed by the mayor, would require the city agencies to transfer over their land.
The front door strategy has been referred to as a "virtual land bank," said city Deputy Managing Director Bridget Collins-Greenwald.
"We think having a real land bank is probably a good idea. We're at the beginning of these conversations with Council," she said. "I think we all have the same goal - get this land back into the most productive use."
Creating a land bank requires state authorization. State Rep. John Taylor (R., Phila.), has submitted a bill in the House to do that.
Also in Council Thursday, Councilwoman Blondell Reynolds Brown introduced a bill to allow advertising on city school buses.
She says the measure could raise up to $1.2 million for the cash-strapped schools. Alcohol, tobacco, and political ads would not be permitted.
The State of New Jersey authorized its school districts to sell ads in 2011. Bucks County's Pennsbury School District was believed to be the first in Pennsylvania, when it signed a $424,000 advertising contract last year.
Contact staff writer Troy Graham at 215-854-2730, tgraham@phillynews.com, or @troyjgraham on Twitter.