Four Papers Accepted to the 2017 Water NZ Stormwater Conference

3 April 2017

Four members of the Stormwater360 team (Mike Hannah, Troy Brockbank,  John Cheah & Kevin Jonathan) have been involved in writing papers for the upcoming stormwater conference;

Are Quality Control/Assurance Procedures Needed for Bioretention Treatment Devices?

John Cheah, Troy Brockbank & Michael Hannah

Bioretention treatment systems have high pollutant removal potential and are a common BMP to use in water-sensitive urban design. However, many bioretention systems do not perform to their design specification due to poor device design and installation, uncontrolled media manufacture, exposure to construction site waste and catchments with unstable soils, and lack of maintenance.

The focus of this paper is on stressing the need for QA/QC throughout all stages of a bioretention devices life to ensure long-term treatment objectives are continually met. The paper will have an emphasis on device design, media manufacture, installation and commissioning and finally maintenance.



When Grey Meets Green - A Hybrid Story

Troy Brockbank & Kevin Jonathan

A hybrid system is an integrated treatment approach that blends innovative engineered stormwater management technologies with more traditional land-based water sensitive design practices and/or conventional landscaped areas to overcome space and cost constraints. There is also an opportunity to design each device, in a hybrid treatment train, to target different contaminants for challenging sites or retrofitting devices on existing site. This paper will present case studies of projects where hybrid treatment systems has been applied. It will provide further discussion in regards to the benefits of using a hybrid design. In particular, performance, space constraints, and costs.


Innovative Stormwater Treatment Asset Conversion at Auckland Motorways.

Troy Brockbank (Co-author)

This paper outlines details of a NZ Transport Agency “Think Outside the Box” award winning, innovation project. The project involved the conversion of an unsafe and inefficient Stormwater treatment device, from a Sandfilter into a StormFilter. This project is a great example of how a project team can ‘innovate’ to achieve ‘resilient’ and ‘future ready’ outcomes. This innovative project also involved retrofitting hydraulic & operational enhancements to the existing infrastructure and partnered design and construction to deliver functionally successful and innovative outcomes.



Permeability of Raingardens – Field Measurements and Observations in Auckland.

John Cheah (co-author)

Raingardens are a popular Water sensitive design (WSD) practice for at-source pollution control and have been used in Auckland for the last decade and a half. This paper presents research on the hydraulic performance of raingardens over time. Six Auckland-based raingardens were selected for permeability testing based on the availability of historical data. Additionally, the state of maintenance and factors affecting the performance were assessed. If results of this small study are indicative of the performance of similar devices across the Auckland region, there is the reason for concern regarding hydraulic performance in achieving objectives for stormwater treatment.



Stormwater360 are proud to be premier sponsors of the annual New Zealand Stormwater Conference for the 13th consecutive time. Feel free to swing by the Stormwater360 booth for a general chat about all things stormwater.

This years 2017 Water New Zealand Stormwater Conference will be held In Auckland at the Pullman Hotel between 3-5 May 2017.

For more information on the conference or to register visit: