Water treatment: We now use polymer instead of alum due to galamsey – GWCL
The Ghana Water Company Limited (GWCL) has disclosed that they have been compelled to switch from alum to polymer for water treatment due to galamsey activities.
According to the Communications Director of GWCL, Stanley Martey, the turbidity levels in the water bodies have exceeded 10,000 NTU(Nephelometric Turbidity Unit) as a result of galamsey, rendering alum ineffective in the treatment process.
Mr. Martey said, “Initially we were using alum but now the alum is almost ineffective and we are now using polymers.”
According to him, the use of more dangerous chemicals to treat water is affecting the staff health-wise as they inhale the chemicals.
This comes after illegal mining activities polluted several water bodies in the country.
GWCL in October 2022 noted that the cost of producing water has increased tenfold as a result of illegal mining activities, hence management has resolved to pass the cost to the consumer.
In March 2023, GWCL bemoaned the high cost of water treatment, particularly in the Western Region.
The company said it is spending extra money on the treatment of water for residents of Sekondi-Takoradi and its environs as a result of pollution of the River Pra.
It is burdened with spending huge sums of money on chemicals to treat high turbidity levels of raw water at various extraction stations.
The official added that given the surge in the cost of processing water for public consumption, the company has no choice but to pass on the cost to the consumer.
“They (PURC) might not give us full cost but a lot of activities have changed. All those parameters would have to be considered in reviewing the tariff as long as we continue to carry out some of these activities.
“Let the quality of water get to the level the Ghana Water Company will take, then the cost will be taken out, your tariff will come down, then the other ones we cannot control, we maintain them. But if the ones that you can control are the self-inflicted ones, the cost must be passed on”, he explained.
Water treatment with alum and polymer
Alum (aluminum sulfate) is a nontoxic liquid that is commonly used in water treatment plants to clarify drinking water.
Its use in lakes began in the early 1970s and is used to reduce the amount of phosphorus in the water.
On the other hand, polymers are mostly used in wastewater treatment. Besides separating solids from liquids, they also help thicken sludge and dewater contaminated material for easier handling and disposal.
Removing the water content from a waste sludge can change the waste properties from liquid to solid waste.