While most in Congress grapple with the imcomprehensible number 792 billion, Rep. Joe Knollenberg, a visionary Republican from Michigan’s 11th District, is tackling a much smaller figure of much more immediate importance to the average American — 1.6.

Not dollars, but gallons; the gallons contained in those water-conserving low-flow toilets mandated by federal law since 1992. The water-conserving low-flow toilets that don’t work.

Nor do they conserve water. Rep Knollenberg bases his attempt to repeal the law and to start over on this unassailable logic that millions of mopping and moping homeowners can verify: The toilet has one specific, all-or-nothing function; 1.6 gallons doesn’t get the job done; when these new commodes don’t clog, they often require two or three flushings to accomplish their specific function, thereby exceeding the old 3.5-gallon standard. Therefore, they don’t save water.

Rep. Knollenberg is opposed in his heroic quest by colleagues, likely at the behest of the powerful plunger lobby, who maintain that theorectical water conservation is better than the real thing. It is, after all, easier to saddle the citizenry with ineffective fixtures that it is to address serious water-conservation issues, like the federally subsidized migration of millions to sun-drenched states that don’t have enough water to support themselves.

One would think the country that can put a man on the moon could, through diligent scientific inquiry, determine just how much water — maybe 1.9 gallons, perhaps 2.3 — it takes to produce an effective flush. NASA’a not doing much these days and it certainly appears that loose-lipped researchers at the nation’s nuclear labs have a lot of time on their hands.

Alas, there are no rocket scientists at work here. The Plumbing Manfacturers Institute is opposed to the repeal because its constituents’ assembly lines are set up for the 1.6-gallon model. A hint to the PMI: the opportunity to market a product that actually works and that millions of people want usually is a good thing. Try it sometime.