PETALING JAYA: Unscheduled water disruptions caused by pollution could pose health risks to consumers, say water conservation groups.
Referring to such water cuts which had happened of late in the Klang Valley, Association of Water and Energy Research Malaysia (Awer) president S. Piarapakaran said there were several ways pollutants could enter the human body, with the highest risk of exposure being through the inhalation of chemicals.
“Ingestion can also occur through drinking polluted water or even consuming contaminated food given how pollution to the environment also affects our food chain,” he said.
Although chemicals could be excreted from the body (at low dosages), Piarapakaran said other chemicals such as heavy metals could accumulate in the body.
“There are also chemicals that can cause cancer, disrupt endocrine systems, harm certain bodily organs and other health implications.
“These pollutants can be absorbed by the soil, leaving them exposed to the flora and fauna of the area, causing the food chain to be contaminated,” he said.
He said a crucial part of understanding pollution was knowing what chemicals were involved.
“In odour pollution, for example, such instances are measured through the Threshold Odour Number (TON) value, but this (value) does not indicate the chemical’s harmfulness.
“Instead, the value only indicates the strength of the odour which can be caused by animal farm wastewater or worse, toxic industrial waste. Its impact, however, is world’s apart,” he said.
He said there were two forms of pollution, namely one involving water intake points for drinking water and the other involving rivers that were not part of water intake purposes.
“When a water treatment plant operator at consumption rivers sees oil spots or detects criteria of pollution, the treatment plant will be shut.
“Many instances of pollution go unnoticed at rivers that are not part of water intake for drinking purposes,” he said.
He questioned how some cases of pollution were resolved through diluting the polluted water with more water to flush the pollutants.
“There were (odour pollution) instances in Sungai Selangor that received such a response but the question is where do these pollutants end up? Kuala Selangor is a seafood zone and that is where Sungai Selangor ends its journey,” he said.
Water and Energy Consumer Association of Malaysia president Saravanan Thambirajah said a water enforcement unit or agency was required to look into potential pollution issues.
“The Federal Government currently has no control over rivers given how they fall under state authorities. State governments must take extra effort on this,” he said.
Illegal dumping also tend to occur during the rainy season, he said.
“The perpetrators’ modus operandi is to dump them during downpours as they think the rainwater can flush away the materials easily without any consideration for the waterways and the ecosystems.
“There have also been instances where hazardous materials were disposed of into sewerage manholes,” he said.
Pengurusan Air Selangor Sdn Bhd (Air Selangor) acting chief executive officer Abas Abdullah said there were various pollution indicators that would result in unscheduled water disruption.
“This includes high raw water turbidity due to land clearing activities or slope failures at the upstream of water intake, and objectionable odour originating from various sources such as illegal industrial and domestic discharge,” he said.
He noted that the duration of water supply recovery to areas affected by unscheduled water cuts varied depending on several factors.
“This includes the filling of reservoirs alongside building up water pressure at the said distribution systems.
“The topography of supply areas alongside distances of impacted water treatment plants to consumers premises are also factors affecting the duration (of water supply recovery),” he said.
He said Air Selangor was continuously monitoring raw water quality entering water treatment plants through an online analyser and manual two-hourly testing, among others.
“We also have a dedicated river surveillance team that works closely with Lembaga Urus Air Selangor (LUAS) to ensure raw water supplies are safe to be treated.
“This is done through continuous river surveillance and raw water quality assessments at various locations in catchment areas,” he said, adding that these parameters were manually monitored up to four times daily.
