Adaptation Strategy: Secondary Dikes

Secondary dikes work in conjunction with primary dikes to reduce the impact of a flood if the primary dike is breached.¹ Several secondary dikes designs may be similar to that of a primary dike but on a smaller scale. For example, in the city of Winnipeg, and secondary dike is simply defined as (any permanent dyke or other flood control work within the City of Winnipeg which has been, or is, constructed between a primary dyke and the channel). Hence, secondary dikes are classified based on their position and the role they play in flood mitigation. In the Netherlands, secondary dikes were historically known as ‘sleeper dikes’: a backup dike which is located between the main dike and the land.² Today, secondary dikes are still a viable adaptation strategy and are usually placed behind the main dike to protect high-value residential land in the case of a breach. In between the main dike and secondary dike are the least sensitive assets such as parks and open spaces that can withstand flooding.