If it took Hurricane Katrina to improve New Orleans' failing public school system, one shudders to think what it will take to improve Washington's. A recent study by the DC Fiscal Policy Institute underscores this grim reality.

Between 2008 and 2012, while the District was spending record amounts of money on its traditional public school system under former Chancellor Michelle Rhee's widely heralded "reforms," a third of the city's schools "saw a notable decline in proficiency" in reading and math as measured by the DC Comprehensive Assessment System test. The declines were concentrated east of the Anacostia River, which were already far below basic proficiency levels.

"Schools in Wards 4, 5, 7 and 8 face declining proficiency levels," the FPI report noted, while "typical school proficiency level grew the most in Wards 1 and 3." So the achievement gap between affluent and high-poverty neighborhoods has actually widened.

In contrast, charter schools as a whole posted solid gains in reading and math at almost every grade level, with the exception of high school reading, which stayed about the same. But DC Public Schools saw losses in both reading and math across all age levels, with the only bright spot being a slight increase in middle school math scores. And despite $10,000 teacher bonuses and other inducements, a worrisome drop in reading proficiency at the elementary level is a harbinger of future failure.

When CBS reporter Scott Pelley asked New Orleans Mayor Mitch Landrieu about the condition of the Big Easy's school system the day after Katrina hit, Landrieu replied that not only was every school under water, but "in terms of governance, it just disappeared." The state-run Recovery School District made a conscious decision to replace the old public school system -- which like D.C. had a graduation rate below 50 percent -- with mostly charter schools.

"Chartering is the replacement system for the failed urban system," Andy Smarick, author of "The Urban School System of the Future," pointed out during a panel discussion in the District in January. The chartering process is dynamic, he says, and creates "a continuous improvement cycle" that replicates high-performing schools and closes failing ones.

So seven years after Katrina, New Orleans "has nearly caught up with the state average in student proficiency," and its high school graduation rate last year exceeded both the state and national average. Meanwhile, DCPS students continue to lose ground.