Resurrecting Ross Creek - An innovative security of supply strategy for Dunedin

In Dunedin, on 9 December 1867 the private Water Works Company commissioned the Ross Creek Reservoir. This was New Zealand’s inaugural major urban water supply, fuelling the rapid expansion of the City during the Otago gold rush and today is New Zealand’s oldest surviving large dam.

The city was soon on the search for new catchments and expanded to take water from the remote Deep Creek and Deep Stream catchments. These pipelines weave for over 60km through ‘tiger country’ and cross the Taieri River together on a 1936 steel arch pipe bridge spanning 70m in a steep sided gorge before reaching the City. Today these systems are still the only means to supply Dunedin’s high levels, accounting for at least 40% of the City’s daily water demand.

With the Deep Creek Pipeline showing advanced signs of deterioration a ‘lifelines’ study was initiated for the replacement of these $110m assets. A long term, risk based strategy was required for determining the optimum timing; alignment; and configuration for renewal of the pipelines.

Learn about this award winning project where the surprisingly affordable risk mitigation for this ‘critical’ infrastructure was right on our doorstep and how Dunedin City Council aim to realise potential savings of up to $11.2m on existing LTP budgets and significantly reduce risk by augmenting existing systems and resurrecting New Zealand’s first major urban water supply.