Go to Site Index See "Articles" main page
10th June 2016
Continued from Part 1...

Dam reservoirs can bring spike in earthquakes

Hydroelectric reservoirs themselves can and do induce earthquakes. After the massive Three Gorges Dam was built in China, for example, more than 3,400 earthquakes were recorded in seven years after the dam's reservoir began to fill in June 2003. The frequency of earthquakes was 30 times greater than before the dam.

A network of groundwater testing wells would help people in the region understand what might occur as the Site C dam goes from concept to potential reality over the coming years.

The reservoir that would be created by the dam would flood nearly 110 km of the Peace River valley and side valleys.

Should the dam be completed, rising waters are expected to cover ground vegetation that will react with the water to contaminate it with methylmercury, a substance that continues to poison fish in the massive Williston Reservoir nearly 50 years after the first dam on the Peace River, the W.A.C. Bennett Dam, was completed in 1968. First Nations people and anglers are warned not to eat fish from the artificial lake. Meanwhile, its shores continue to erode and slide into the reservoir, causing further contamination.

Johansson worries that other landslides like those at Brenot Creek could occur in future years, leading to a steady increase in the amount and variety of other waterborne toxins that could one day accumulate in the Site C reservoir.

Toxic water impounded by the dam would have to be released to power its hydroelectric turbines, meaning the water would then flow downstream toward the wildlife rich Peace-Athabasca delta, one of the world's largest freshwater deltas and a critically important staging area for migrating birds.

Meanwhile, as Site C construction activities accelerate, members of UNESCO's World Heritage committee are about to conduct a study into the impacts that the dam could have on Wood Buffalo National Park, a World Heritage Site. The investigation was prompted by a petition from Alberta First Nations concerned about the potential downstream impacts of the $9-billion hydroelectric project. The committee has asked the federal government to ensure that no irreversible work on Site C takes place until it has completed its report. [Tyee]