This recently discovered drainage pipe, likely dating back to the 1880s, was constructed to channel a creek beneath an earth bridge that conceals the old water race (pipeline/culvert). Without this drainage pipe, the earth bridge would act like a dam by causing water to accumulate and exert unnecessary pressure on the wall of the earth bridge.
The earth bridge itself was once part of Maintenance Road, that provided access to the water race and later to the Orongorongo pipeline. The road was also widened to allow vehicles access to the Orongorongo pipeline. While this road remains to this day, this end section of road was abandoned years ago and has since been reclaimed by the bush. Consequently, the drainage pipe is now hidden in dense bush.
