If I believed taxing carryout bags in Montgomery County would improve local water quality and protect our waterways, I would be the first to sign on. But the five-cent tax on both paper and plastic bags proposed by County Executive Ike Leggett won’t save the Chesapeake Bay. What’s worse, it would have unintended consequences — some silly, some serious.

And if the tax wouldn’t save our streams, then it better save our equally stressed budget. But it wouldn’t do that, either. It would give Montgomery County residents nothing while leaving them, well, holding the bag.

A study by the Alice Ferguson Foundation, an environmental and education group working to clean up the Potomac River, showed a drop in bag use after the District’s bag tax went into effect last year, but it’s important to note that the effect on city waters has not yet been quantified; a reduction in bags does not necessarily mean a reduction in litter.

As a dog owner, I put my old grocery bags to good use a second time, and that makes me one of the 90 percent of consumers who reuse their grocery bags at least once. Taxing people who already exercise good judgment isn’t going to change the attitudes of rogue litterbugs.

My larger concern, though, is that this tax — which will come up for a public hearing on March 31 — is regressive, placing the heaviest burden on those with the lowest incomes. The added expense of paying the tax or buying reusable bags may not be much of a problem for the wealthy; not so for families already having a hard time making ends meet. I foresee scenes in which residents, perhaps senior citizens, overload their shopping bags to save money, only to spill groceries all over the sidewalk on the walk home. That’s not saving anybody’s environment.

And speaking of environments: The one inside a reusable bag is perfect for growing bacteria and cross-contaminating food, so if you opt against paying for disposable bags, you had better remember to wash your reusable ones. Do you really want to carry home unwashed chicken or seafood in a bag you might be carrying apples in later?

But most important, this proposal is a distraction from the fiscal crisis we must face right now. To literally nickel-and-dime residents this way might bring in $1.5 million in revenue under the best-case scenario, but that’s a drop in the bucket compared with the huge shortfall Montgomery County is confronting.

Don’t get me wrong. I have real concerns about the environment, and I agree we should look at viable solutions to our pollution problems. That might mean reexamining the Water Quality Protection Charge that residents already pay as a part of their property tax bill and which has a proven track record of success.

Right now, though, we need to focus our time and attention on how we can maintain needed services, treat employees fairly and invest in our future, all while slashing spending. That’s our real mandate.

I say, bag this tax.

The writer, a Democrat, is an at-large member of the Montgomery County Council.