This is the old railway bridge we cycled over about three weeks ago (the one that leads directly into the 1km long tunnel). The Ohinemuri River runs through the gorge and a few days ago, part of this river turned bright orange with some sediment from a disused mine shaft. There was a scuffle to quickly get water samples to check for contaminants. The river seemed to run clear a couple of days later, so hopefully there has been no long-term damage to the ecosystem.
