The sale of commonly used phosphate detergents would be banned in the region under a proposal endorsed by the Metropolitan Washington Council of Government's water board.

Although the board -- which includes representatives from all local governments -- approved a smiliar proposal three years ago, local jurisdictions declined to act on it at that time.

This time, the board's action is backed up by more evidence that the ban would produce savings in sewage treatment.A ban also now has the support of more public officials and utilities, and the Virginia State Water Control Board will drop its longstanding opposition if COG can prove it would not cost consumers more than would be saved in sewage treatment costs.

Before a ban can go into effect, local jurisdictions have to approve it.

COG staff have estimated that a ban on phosphate-based detergents -- whose pollutants add to the volume of sewage sludge -- would save $2.8 million a year in sludge disposal costs. The savings would increase as area treatment plants move toward full capacity and could reach as much as $3.3 million.

Disposal of sewage sludge has become a major environmental and fiscal problem in the area. As the Blue Plains regional treatment plant in the District and other facilities have improved their ability to clean up waste water, they have generated thousands of tons of sludge, a byproduct of the process, every day. The cost of disposing of this sludge has increased dramatically in the last five years because of inflation and the enormous increase to volume.