The second problem: there was weed in Lake Rotoaira in the Tongariro scheme. Now, ordinarily, it's kept clear of the intake in that scheme, but, as it happened, there was a south-east gale all that day, which pushed the weed into the intake. As it even turned out, the workers in that scheme actually had it under control until about, alas, just before the evening peak, just exactly when we needed it to be clear. So something went wrong with the way that the weeds are controlled—normally it's OK, but it couldn't cope that particular day.