Eastern Selwyn Sewerage Scheme - Planning for Growth, But Planning it Wisely

The Eastern Selwyn Sewerage Scheme (ESSS) was developed to meet the existing and future needs of the towns of Prebbleton, Lincoln and Rolleston. The purpose of this scheme is to ensure a staged and managed approach to the development of wastewater bulk conveyance, treatment and disposal infrastructure while providing equality in the scheme costs for existing residents, new developments and future generations. 

A structured approach was taken to define the limitations of the options considered, and to develop an equitable approach for each of the communities. Considerations were made on how best to use existing assets to offset the capital expenditure of the scheme. These are investments already made by existing ratepayers and, if used appropriately, could benefit the final solution.

A balance was made between the need to accommodate immediate growth and develop infrastructure required to cater for the future flows expected from the changing needs of the communities. Components of the scheme were staged to either allow upgrading without compromising ongoing operations or developed in a modular fashion to minimise the impacts of future construction. 

This paper examines the processes considered, approach taken and the option developed to meet the Council’s challenges.