District residents and business owners will be subject to fines if they don’t swiftly clear snow from the public sidewalks in front of their property under a bill given final approval by the D.C. Council on Tuesday.

Property owners have long had a duty under city law to clear walks of snow within eight daylight hours of a snowfall. But enforcing that duty has been difficult, if not impossible.

The current statute, on the books since 1922, allows the city to clear walks and then sue the property owner to recover the cost. Asked by the council whether such lawsuits had ever been pursued, the D.C. attorney general could not identify any case.

The bill that passed Tuesday would allow city employees to write $25 tickets for a residence and $150 for a business not cleared within 24 hours of a snowfall. Seniors and those with disabilities are exempt from residential fines.

The measure won approval after several years of attempts from Mary M. Cheh (D-Ward 3) to create a workable snow-shoveling enforcement regime. The fine structure is based on similar laws in New York, Boston and Philadelphia, as well as in Arlington and Prince George’s counties.

Cheh called shoveling a “safety issue” that demanded effective enforcement. “The law’s been on the books for 90 years,” she said Tuesday. “And now, finally, there will be a practical way to enforce it.”

It remains unclear how widely the fines will be enforced.

The District’s chief financial officer refused to certify any revenue from the bill, citing “difficulties with enforcement and lack of historical record of sidewalk related complaints.” The city employees who would be empowered to issue the fines — in the police, transportation and public works departments — would almost certainly have other duties to fulfill after a snowstorm, the CFO’s office noted in its analysis.

Mayor-elect Muriel E. Bowser (D-Ward 4) was one of three members to oppose the bill, arguing that enforcing the fines would “spread resources thinner and not accomplish anything more.”

“This is causing more of a problem than it’s meant to solve,” she said.

Jim Graham (D-Ward 1) also voted against the bill, although he said he recognized the problems with the existing law. “There’s a reason we’ve had this goofy law for as long as we have,” he said. “It’s virtually unenforceable.”

He predicted “a lot of irritation” from residents, much like the objections he has encountered from those written tickets for the seemingly ubiquitous practice of jaywalking. Marion Barry (D-Ward 8) was the third member in opposition.

But most members voted to support the bill, particularly after Council Chairman Phil Mendelson (D) moved an amendment to streamline what had been a system of graduated fine into flat fines for each violation.

No fines will be levied this winter; the bill will not be effective until Oct. 1 — and after the mayor’s office writes the rules on how the fines will be levied and adjudicated, a process that could be complicated by Bowser’s opposition.

In other business Tuesday, the council gave initial approval to a bill banning “conversion therapy” for minors — that is, counseling that seeks to turn gay individuals straight. Major medical policy groups have taken positions against the practice, also known as reparative therapy or “reorientation,” but bans passed in the California and New Jersey legislatures have faced court challenges.

Also winning support in the first of two votes was an anti-human-trafficking bill that, among other things, removes criminal penalties for minors who engage in prostitution. Anti-trafficking advocates have pushed for the measure, saying criminal prosecutions only compound the complex problems that victims face.

A council report on the bill said that the change reflects “the view that children being sold, or selling themselves, for sex is a form of abuse that victimizes the children.”

Action, meanwhile, was delayed on a bill that would restrict the ability of city correctional agencies to restrain pregnant women with handcuffs, leg irons or shackles. Mendelson moved to delay consideration after raising concerns that the measure could be overbroad.

Bills receiving final approval included a measure setting a minimum funding level of $100 million for the city’s main affordable housing program and another requiring paint manufacturers to set up a recycling program and authorizing them to charge a fee to fund it. In states that have implemented similar programs, the retail price of a gallon of paint has risen by about 75 cents, a council report said.

The council also voted to hire a former member, Kathy Patterson, who represented Ward 3 as a Democrat from 1995 to 2007, as the new District of Columbia auditor — a post meant to assist the council in its government oversight role.