Abstract
For thousands of years, the broad expanse between Sumas and Vedder Mountains east of Vancouver lay under water, forming the bed of Sumas Lake. As recently as a century ago, the lake's shores stood four miles across and six miles long. During yearly high water, the lake spilled onto the surrounding prairies; during high flood years, it reached from Chilliwack into Washington State. Then, through the 1920s, a network of dykes, canals, dams and pumphouses was erected and the lake drained - "reclaimed" in the words of projects supporters.