Muriel Bowser is seen during a D.C. mayoral debate on Thursday in Washington. (Linda Davidson/The Washington Post)

Facing criticism from opponents, Democratic mayoral nominee Muriel Bowser released a platform Thursday that adds depth to her education plan, lays out new public safety and transportation initiatives and makes other concrete pledges for her potential mayoralty.

The 41-page platform — released shortly before the election season’s first debate — appeared timed to blunt attacks, particularly from independent rival David A. Catania, that Bowser has been deficient in laying out her vision for the city. But Bowser barely mentioned the document during the debate, which featured sharp exchanges over ethics reform, education, housing and other issues.

An NBC4/Washington Post/Marist poll released this week found Bowser with a 17-point lead among likely voters but leading Catania only slightly — 33 percent to 30 percent — on the question of which mayoral candidate has the clearest vision for the city’s future.

On Monday, Catania released his own “Vision to Secure Our City’s Future,” pitching himself as the most substantial candidate in the race; fellow independent Carol Schwartz has also issued a lengthy education paper.

Bowser’s platform contains a number of specific proposals, a few of them mildly controversial.

For instance, on education, she pledges to “increase collaboration” between charter schools and traditional public schools. She would empower her deputy mayor for education to “make recommendations” in that area — including around “efforts to locate charter schools and provide a neighborhood preference,” prospects that most charter school advocates have resisted. Bowser also pledges to raise $50 million in private funds to supplement school funding, a practice that has generated some discomfort in the past.

Most of the platform’s planks, however, are widely palatable proposals that involve bringing new focus to ambitious but uncontroversial goals.

On education, she proposes to “completely transform” the city’s middle schools by 2020, intensify efforts to make school budgets more transparent and expand the “SchoolStat” data-driven accountability system used by the D.C. public school system.

The platform also reiterates her support for keeping Kaya Henderson as schools chancellor. “Continuity in leadership at DCPS is the best way to ensure the District’s reform efforts move forward uninterrupted,” the document reads.

To promote employment and economic growth, Bowser proposes to “elevate” the city’s small-business agency above its current mission of certifying local businesses for government contract opportunities, refocusing it on helping local businesses grow. She pledges to “enable a new business owner to obtain a business license in less than one day — and renew it quickly online” — and make the city’s capital-gains tax rates and licensing fees more competitive with neighboring jurisdictions’.

Bowser also pledges to create an Office of Public Private Partnerships, similar to agencies developed in Virginia and elsewhere, to help fund large-scale infrastructure projects — including school modernizations, Metro expansion and sewer system updates.

On housing, Bowser pledges to devote at least $100 million a year to the city’s Affordable Housing Trust Fund, its main mechanism for financing low-income housing; require “at the very least” that 20 percent of housing units built on public land be affordable to low-income households; and pursue a “multi-pronged approach” to end family homelessness by 2018.

She proposes to close the city’s troubled family homeless shelter at the former D.C. General Hospital but does not commit to a specific timeline.

Public-safety proposals include hiring a new fire chief with a “strong EMS background” to address problems with the city’s emergency medical response; establishing a “crime and violence prevention hotline” to be promoted in schools in hopes of preventing incidents before they spiral out of control; and expanding the police force beyond 4,000 officers “when it becomes necessary.”

On transportation, Bowser says she will “lead a comprehensive assessment” of the District’s streetcar project, saying residents “have been rightfully concerned about the project’s excess costs and delays” — a stance that separates her from Catania, who committed in his own platform to a full build-out of two streetcar lines. Bowser also proposes to appoint an “innovative leader” atop the city transportation department, complete the Metropolitan Branch Trail and convene a “parking and congestion task force.”

Other proposals include hiring a “chief innovation officer” for the city, who would “find more open and accountable ways to create government efficiencies”; establishing a Board of Health “responsible for advising the Mayor and the agencies under her lead . . . on policies and regulations that best serve the community”; launching a new citywide health-and-wellness campaign; and making new commitments to environmental programs and strategies.