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Diavik's dike of distinction
How an innovative project in the Canadian Arctic has bought plaudits from the civil engineering industry.

May was a special month for Diavik Diamonds. Its 4km dike, built to keep the waters of the Lac de Gras at bay so that mining could begin, was named as the most significant Canadian engineering achievement for the year 2002.

The need for a dike was identified in the mid 1990s, when the Diavik team discovered four diamond bearing ore bodies just offshore of a 20sq.km island, under the water of Lac de Gras, a 60km arctic lake 300km northeast of Yellowknife, capital of Canada's Northwest Territories.

Engineering feasibility studies showed that the only way the diamonds could be recovered was by open pit mining. This would require the design and construction of a structure that could safely keep off the waters of Lac de Gras - something never achieved before under such difficult conditions. Without a safe, dependable, economically feasible structure, there would be no Diavik Diamond Mine.

Diavik's team began investigating how this could be done, including collecting bathymetry data of the Lac de Gras lakebed, geological and geotechnical investigation of the foundation, sediment movement and dike alignment studies, cross section analysis, and a search of the world's dam technologies.

Through 1998 to 2000, the Diavik engineering team designed what would become called the A154 dike, surrounding the A154 South and North ore bodies.



Diavik's dike of distinction How an innovative project in the Canadian Arctic has bought plaudits from the civil engineering industry. May was a special month for Diavik Diamonds. Its 4km dike, built to keep the waters of the Lac de Gras at bay so that mining could begin, was named as the most significant Canadian engineering achievement for the year 2002. The need for a dike was identified in the mid 1990s, when the Diavik team discovered four diamond bearing ore bodies just offshore of a 20sq.km island, under the water of Lac de Gras, a 60km arctic lake 300km northeast of Yellowknife, capital of Canada's Northwest Territories. Engineering feasibility studies showed that the only way the diamonds could be recovered was by open pit mining. This would require the design and construction of a structure that could safely keep off the waters of Lac de Gras - something never achieved before under such difficult conditions. Without a safe, dependable, economically feasible structure, there would be no Diavik Diamond Mine. Diavik's team began investigating how this could be done, including collecting bathymetry data of the Lac de Gras lakebed, geological and geotechnical investigation of the foundation, sediment movement and dike alignment studies, cross section analysis, and a search of the world's dam technologies. Through 1998 to 2000, the Diavik engineering team designed what would become called the A154 dike, surrounding the A154 South and North ore bodies.
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