Public Relations Officer of the Ghana Water Company Limited (GWCL) in the Central Region, Nana Yaw Barima Barnie, has disclosed a shift in the chemicals used to treat water from the Pra River for public consumption.

According to Mr. Barnie, aluminum sulfate, commonly known as alum, is no longer being used by the GWCL due to its ineffectiveness in producing clean water. This development is attributed to the heavy pollution of the river caused by the activities of illegal miners in the area.

In a media interview, Mr. Barnie stated that the GWCL has now resorted to using polyelectrolyte, which has significantly increased the company's financial burden.

“River Pra has been polluted to the extent that aluminum sulfate is no longer effective in treating water from River Pra. But we need to treat the water anyway, and so we have gone in for another chemical called polyelectrolyte or polymer,” he explained.

The Public Relations Officer further noted that using polymers for water treatment is four times more expensive than using aluminum sulfate. “It means that our treatment cost has gone up,” he added.

Aluminum sulfate is a chemical compound that is primarily used in water treatment due to its ability to cause impurities to clump together, making it easier to remove them from the water.

How Aluminum Sulfate works in water treatment

Research indicates that when aluminum sulfate is added to water, it reacts to form a gel-like substance called aluminum hydroxide. This process lowers the water’s pH and helps coagulate or flocculate suspended particles, dirt, bacteria, and other impurities. These impurities bind with the aluminum hydroxide to form larger particles, or flocs, which are easier to filter or settle at the bottom for removal. This essential process is known as coagulation and flocculation and plays a vital role in water purification.

Polymers, which are large molecules made of repeating structural units derived from smaller molecules (monomers), are commonly used in water treatment. Synthetic polymers, in particular, enhance the purification process.

Recent videos on social media show the water from the Pra River appearing deep brown, signaling extreme contamination levels.

In related news, four individuals believed to be responsible for the severe pollution of the Pra River through illegal mining activities have been apprehended.

The consequences of the river's contamination extend beyond the destruction of the water source and the lack of potable water for surrounding communities. Recent developments indicate that the contaminated water is now being used for irrigation, posing a significant public health risk.