Dam Remediation
Completed in November 2005 for Alpine Energy, this $240,000 project involved rebuilding the Lake Ophua Dam in South Canterbury, making it stronger and safer.
Overview
The project involved removing a section of the dam crest and rebuilding it with new materials allowing water to filter through. The eight week contract was completed in only four weeks.
- Overview showing removed section.
- View looking along the dam.
- Removing the dam crest.
- Rebuilding.
Health + Safety Management
Removing a section of the crest weakened the dam, making it vulnerable in the event of heavy rain. This sensitive situation was addressed with a series of emergency plans and staff training specifically for the project.
Environmental Management
Resource consent specified the restriction of sediment discharge to the air or ground and a fuelling ban on the dam.
The moisture content of the material involved was high enough to prevent dust or sediment entering the lake. However, the fuelling ban had a significant effect on the project. A methodology was established, in which a section of the crest would be opened in the morning and back filled it by the end of the day, allowing plant to exit for fuelling.
During the project, the hydraulic pump of an excavator blew, spilling hydraulic fluid onto the dam crest. The accident was responded to quickly with an on hand oil spill kit and the machinery was replaced, allowing work to continue almost immediately.
More Information
If you would like to find out more information about our work on the Ophua Dam remediation, please contact us.