The best way to cope with Africa's water pollution problems is through prevention, says a senior expert with the United Nations Environment Program.

"There are very strong indications that in a number of areas (in Africa), the water quality is deteriorating," Dr. Thomas Chiramba, head of the UNEP Freshwater and Ecosystems Unit, told Xinhua during an interview Thursday.

"My strong suggestion is prevention. I am saying so is because that prevention is the easiest and cheapest way of doing it," Chiramba said after giving a speech during a seminar at the ongoing World Water Week.

A main source of pollution, Chiramba said, is urbanization that is gathering pace without a corresponding growth of sanitation facilities, particularly waste water treatment measures.

He said that about 80 percent of the sewage discharged into rivers is untreated except in a few countries like South Africa, Namibia and Botswana.

Even in some areas that have treatment facilities, the equipment might not function properly, he said, adding that there is a severe lack of infrastructure for treating waste water from urban and industrial areas.

Chiramba said that some industrial pollution is moving from industrialized countries into Africa where environmental laws are less stringent and poorly enforced.

Another threat of pollution comes from the increased use of fertilizers in agriculture because it could result in more nitrogen and phosphor in the water, he said.

"The third part I would like to raise is there are chemicals from pharmaceutical products... Those present a very serious source of contamination of water," Chiramba said.

Illegal damping of waste also contributes to the threat, he said.

"The biggest threat is that all these threats are there, but we don't seem to monitor them," he said, "The water might be in good condition, but the threats are increasing and what makes it a serious issue is the fact that we don't have an effective monitoring mechanism."

A big barrier is that water management does not focus sufficiently on water quality while there is a lack of understanding of what is happening to water resources, Chiramba said.

He suggested that monitoring systems need to be established to safeguard Africa's waters.

His second suggestion is to teach farmers to properly use fertilizers and pesticides so that agricultural pollution can be minimized.

Consumption behavior is also important in pollution prevention, he said, adding that if people are aware of the problem and refrain from dumping waste into the water, it will be a good prevention.

Meanwhile, Africa's governments have to prioritize the water management issue and allocate relevant resources to it, Chiramba said.

"I think the political will is better, but it becomes a challenge to translate the political will into reality with more investment," he said. "The political will is handicapped due to lack of awareness, financial resources and human resources."