Optimx Report - an abstract.

The Optimx Report - Future Directions for Alexandra Strategy Study" commissioned and adopted by the Alexandra Community Board 30 June 2000.  

Alexandra Future Directions Strategy Study

The town of Alexandra is located at the confluence of the Clutha and Manuherikia Rivers within the Central Otago District of the South Island of New Zealand. The headwaters of the Clutha river flow from the glaciers of the Southern Alps. The river has a heavy bedload, including the gold which funded the early establishment of the district in the 1850-1880s.

In 1956 the government built the Roxburgh hydro dam 30 km downstream of Alexandra to harness the power of the Clutha. Immediately after Lake Roxburgh was formed, there were concerns that inadequate account had been taken of the effects of trapping the suspended bedload in the newly formed lake, and the risks of flooding this would impose on Alexandra and the surrounding Earnscleugh District. This concern was dismissed by the dam operators but was proven to be valid with the area experiencing three major floods since 1994. As a result of the last flood in 1999, the Alexandra Community Board sought financial assistance from the government, Otago Regional Council, Contact Energy Ltd (the current dam owners), and the Central Otago District Council to commission the Alexandra Future Directions Strategy Study. Optimx was appointed to lead the study and find solutions that met the needs of the four principal stakeholder groups.

The principal task of this project was to prepare a Strategy Study that assembled all of the necessary information in liaison with the Alexandra Future Directions Steering Committee. The Committee was made up of representatives from the Central Otago District Council and the Alexandra Community Board, and was formed to resolve issues on the future of Alexandra in response to frequent flooding.

Optimx undertook a comprehensive consultation process in order to gain a full understanding of the community's requirements for a possible solution. A proposed scheme of flood protection and property purchase was put forward, supported by a preliminary assessment of the situation of risk.

The nature of the work included strategic planning, consultation, and the generation of risk profiles and flood damage assessments.
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Optimx based their work on the Australia/New Zealand Risk Management Standard AS/NZS 4360 as it establishes guidelines for undertaking a risk analysis of this scope, and provided a framework to work with the Steering Committee.

This study led to the government and Contact Energy agreeing to fund $22 million for flood investigation and community development works

This project provides a good example of how Optimx can provide expert advice on floodplain management and assist in preparing solutions that address the needs of quite diverse stakeholders.