Adaptive Consenting and its Application to Stream Works

Urban streams form part of an important dynamic environment that needs to be protected. They are constantly required to adapt and change to meet the constant pressures placed on them by the surrounding environment these changes can occur slowly or sometimes rapidly. When implementing stream enhancement projects sometimes streams have changed so much that what was designed one to two years ago is no longer the best outcome when the contractor establishes onsite; or sometimes streams are covered by such dense bush that the full extent of the issues cannot be evaluated without clearing the vegetation. To minimise these issues an adaptive management approach was adopted whereby a “toolbox” of best practice soft and hard engineering solutions was designed. The consenting authority was engaged to develop the approach that allowed the different “toolboxes” to be utilised on different sections of the stream. Once the contractor established onsite and cleared the unwanted vegetation, the consenting officers, designer, ecologists, Iwi, the contractor and the Engineer met and agreed what “toolbox” options should be utilised to resolve the different issues along the length of stream to be remediated. This flexibility was allowed for in the consent. The outcome; consenting officers, ecologists and Iwi were involved in the process, the designer was more confident that the best “toolbox” was utilised to address the different issues, the engineer was more assured that any variations due to changes were minimised because these were allowed for in the contract documents and the client had more certainty that the best value for money was being achieved.

In this paper and presentation, two case studies will be presented that will explain the process through the consenting phase and the implementation of the physical works onsite.