Depending on your objective, phosphorous can be a good or bad substance with which to treat water.

On the positive side, it can help deal with heavy metals, such as those that have found their way into Lake Coeur d’Alene and the Spokane River as a result of mining activities in North Idaho. On the negative side, it can promote algae growth and diminish the level of oxygen to levels that inhibit fish life.

To learn more about the pros and cons, and to make known your feelings about the use of phosphorous to clean up heavy metals and PCBs in the Spokane River, you can attend a public hearing from 6:30 to 9 p.m. next Thursday in the Barbieri Courtroom at Gonzaga Law School, 721 N. Cincinnati St.

The program, which will include speakers from the U.S. Environmental Protection Agency, the Washington Department of Ecology and the Idaho Department of Environmental Quality, plus the University of Idaho, is presented by the Washington Citizens Advisory Committee.

The WCAC is a grant-funded nonprofit organization charged with raising public awareness about river cleanup issues on the Washington side of the state line and collecting public feedback.

The meeting will give audience members a chance to present their opinions, which will be reported back to the respective agencies for their consideration as policy decisions are made.

People who want to be more involved can attend the WCAC Board of Directors’ regular monthly meetings from 6-9 p.m. on the second Wednesday of each month. Meetings take place in the conference room of the Spokane Water Department, 914 E. North Foothills Drive.