These lakes are particularly prone to strong north westerly winds which create large waves travelling across the lakes. In the case of Lake Pukaki the waves can reach a similar size to those expected in the coastal area. These waves can scour the fine sediments on the lakeshore causing lakeshore erosion. In areas where it is necessary to protect assets such as roading infrastructure, Meridian Energy uses erosion protection techniques to mitigate the effects of erosion and protect the state highway and other local roads. Such techniques include lining the shores of the lakes with large rock material which is strong and is not affected by wave action and placing structures on the shoreline to deflect waves and their energy which cause erosion.