Central Interceptor, Earth Filter Bed 3 & 4 Removal and Reinstatement

Mangere Auckland


Seipp Construction is working with international Construction Company Ghella Abergeldie in a Joint Venture at Mangere WWTP. Work begun in April 2021.
The scope of works consisted of:

  • Removal and reinstatement of Earth Filter beds 3 & 4, 1220m2 & 1378m2 x 950mm deep
  • Supply and mixing of the media material
  • Zero compaction placement
  • Removal and reinstatement of the Earth Filter drainage, uPVC air ducting and irrigation systems
  • Construction of 125m x 1.4m blockwork wall

Project Description

Earth Filter beds 3 & 4 act to remove odours produced by the treatment of Auckland’s wastewater. The new Twin riser main passes directly below each bed, as a result compromising the capacity of the already deficient system. The existing drainage, irrigation and air pipework/ducting was also at the end of its life, requiring a full replacement.

Seipp were engaged to remove and reinstate Earth Filter beds 3 & 4, at the Mangere Wastewater Treatment plant (WWTP). Including the buried pipework and ducting servicing the Earth filters. Bed sizes 1220m2 & 1378m2, respectively, with a depth of 950mm.

A new and improved media composition was proposed to increase the longevity and effectiveness of the Earth filter beds. We further provided suggestions on the media recipe, refining, and improving the original design.