The case of the city employee who tripled her salary to $161,000 by working the equivalent of 71 additional weeks in a single year raises urgent questions about the oversight of Philadelphia's finances.

The city is rightly reviewing how the juvenile detention center worker could amass so much overtime. But why did this money not raise red flags until a report about the overtime by Inquirer staff writer Claudia Vargas? The fact is that in fiscal 2018, the city blew its overtime budget by $40 million. It spent $175 million from the general fund on overtime, a figure that doesn't include higher pension payments, since employees' overtime pay is used to calculate pension payments. It was the eighth year in a row the city blew through its overtime budget.

City Hall has no problem asking taxpayers to dig deeper to fund its growing budget of more than $4.7 billion. But less attention is paid to ensuring that precious tax dollars are well-spent, or that departments are expected to adhere to budget discipline or efficiency.

Many homeowners were walloped with an increase in property-tax assessments this year of as much as 47 percent. That's on top of water rates that have increased by 70 percent since 2007 and gas rates that were hiked by almost 7 percent last year.

In addition, Mayor Kenney increased the already-high real estate transfer tax and slowed the already tiny reduction to the onerous wage tax. The mayor tried to increase property taxes by 6 percent this year, but City Council wisely rejected that idea.

Council members Cindy Bass, David Oh, and Allen Domb developed alternative budget plans that included the practically unheard-of idea in Philadelphia of cutting spending. Recall that during previous Mayor Michael Nutter's tenure, Council went along with four property-tax hikes.

Philadelphia already has one the highest overall tax burdens in the country — the biggest impediment to the city's growing its job base and reaching its full potential.

To be sure, there are increased revenue demands to fund the schools and cover the growing pension costs. But the city can't keep asking the already overtaxed to shoulder the higher costs without seeing more efficiencies, especially given the stagnant wages.

That is why Kenney and Council need to focus more on annual spending. The story of the city employee who tripled her salary with overtime signals the city is not keeping a close eye on its purse strings. (The fact that she is in line to receive a $387,055 DROP payment and an $88,495 annual pension that is 79 percent higher than her salary underscores the need to end DROP and implement further pension reforms.)

As a candidate for mayor, Kenney talked about implementing zero-based budgeting, which would require each department to justify its annual spending and not just seek steady increases. We're still waiting for that good idea to take hold.

Montgomery County, which has a much smaller budget, has saved tens of millions of dollars through zero-based budgeting. Philadelphia could find similar savings and signal to residents that its tax dollars are being well spent.