It's whoa boy (meaning "slow down mate"). They are a bump put the road and adjoining gutter to stop water from running down the road and to direct it off down hill. When properly placed they are an effective erosion control.
Those big concrete pads that form the tower foundation are back filled with several metres of soil, there is a small ring of high strength concrete placed around the tower base but the rest is a level site that actually infiltrates more water than the previously sloping area. At the Macintyre wind farm on traprock country there is more vegetation growing around the tower base than on the surrounding ridge.
