Lake Waikare rarely looks blue. It often looks orange, red or, like today, purple and brown. The twin towers of Huntly Power Station can be seen to the left of the tree in the foreground.
The colours in the lake are due to the poor quality of the water. It's poor quality for a variety of reasons. Despite having a surface area of 34 km² the lake is very shallow at less than 2m deep. The level of the lake was lowered by a metre in the mid 1960s to help with local flood control. As a result of this, and erosion from a local catchment area, there is a lot of suspended sediment so light levels are low and aquatic plants can't grow. There are also high levels of nitrogen and phosphorous in the lake.
@rob24 Thanks. It's quite sad about the lake but we have a very important wetland and conservation area nearby which has been undergoing major restoration works since the 1960s. The lake feeds into the wetland area so if its level was raised it would flood that area and be terribly damaging.
I like that large sky.