The original Technical Publication 10, “Stormwater Treatment Devices Design Guideline Manual” (TP10), was developed in the early 1990s by the Auckland Regional Council to assist stormwater treatment designers. It has been in use in the Auckland region since October 1992 and in the past five years has been used as the design basis for a number of other New Zealand regions.

A large number of devices installed in Auckland in the mid-to-late 1990s and early 2000s are difficult to operate and maintain, primarily due to poor design and construction. As time has elapsed, many practices in relation to the design and construction of treatment devices have been learnt and applied, and as a result stormwater treatment devices have improved.

Council has obligations under the Resource Management Act (1991) (RMA) for the maintenance and enhancement of the quality of water in waterways and coastal waters. This is done in part by controlling the discharge of contaminants into water, or onto or into land. To assist in this requirement the council has developed plans and guidelines for the management of stormwater. This operation and maintenance technical report forms part of the toolbox of information available for those maintaining stormwater treatment devices in the Auckland region.

TP10 has been subject to only one revision incorporating changes in the philosophy and approach in relation to stormwater treatment devices. The manual provides information on the operation and maintenance of these devices; however its focus was primarily on their design and construction; it was not tailored specifically for operational inspection and maintenance. Consequently, the day to day operation and maintenance of stormwater devices required additional information of relevance to network managers, device owners and maintenance contractors.

The objective of this report is to assist the stormwater industry by providing details and advice on the operation and maintenance of stormwater treatment devices commonly used in the Auckland region. In particular it attempts to provide advice on how to overcome operational and maintenance issues, and how to implement good maintenance schedules that prolong the life and performance of each device.

Auckland Regional Council technical report, TR2010/053

August 2010