Chalillo Dam: Don't Drink that Water!

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Toxic water being released from the Chalillo Dam in Belize


See that horrible, dirty water flowing out the Chalillo Dam on the Macal River in Belize? Environmentalists in Belize took these photographs last week after seeing the color of the water in the Macal River. Scary stuff, considering that the Macal River directly or indirectly supplies water for one third of the country.

But don't worry, BECOL, the Belize Electric Company Limited, says that it's harmless silt that is being pumped down the river, and that their tests show no elevated levels of heavy metals in the water. BECOL's Operations Vice President Stephen Usher blames heavy deforestation in the watershed for excessive silt build-up in the reservoir, which is in turn being pumped downstream.

Toxic sludge in the Macal River, Belize


Not so fast, says water quality expert Dr. Guy Lanza, Professor of Environmental Sciences at the University of Massachusetts, Amherst, whose first reaction upon seeing the photos was "Don't drink that water!" According to Dr. Lanza, the water turbidity in the photos is alarmingly high and the result of both organic and inorganic dissolved and suspended material in the reservoir.

Says Dr. Lanza, "The release is a major concern with regard to use of the water for drinking and the overall water quality and ecology in both the impoundment and downstream in the Macal, Mopan, and Belize rivers."

The dirty Macal River meets the Mopan River, Belize


According to Dr. Lanza, the turbidity levels in the river are thousands of times higher than acceptable levels considered safe for drinking water. High turbidity protects disease-causing waterborne microbes such as bacteria, viruses and protozoa by masking their presence and by interfering with the effectiveness of the chemicals used to purify the water for drinking purposes. Also, the materials producing the turbidity will clog the filtration systems used to pre-treat drinking water before using chlorine (or other disinfectants).

"In short," says Dr. Lanza, "you cannot disinfect water with the turbidity levels clearly evident in the photos."

What's even more disingenuous is that BECOL is blaming Guatemalan settlements and Xateros for the deforestation in the watershed. According to Jean Cormec, a geologist who has studied the area, the problem is really the geological make-up of the Maya Mountains, which are made of materials that during the normal tropical weathering process break down into very large amounts of clays, silt, sand and pebbles. Says Cormec, "this is a big mess which is likely to last."

No wonder that BECOL is trying to blame others for the mess: the Challilo Dam was the subject of a huge campaign in the late 1990s and early 2000s by environmentalists who were concerned about the project's impacts on the Macal River. BECOL – which is 100% owned by Canadian company Fortis – claimed the project would have minimal impacts on the environment. Now it looks like BECOL's chickens are coming home to roost, let's hope its not the Belizean citizens that suffer the consequences.