Challenges of Stormwater Treatment for a High Risk Heavy Industry Site

Establishing a heavy industrial site where the activity was in a high risk category for stormwater discharge presented a unique challenge when the combination of treatment, site constraints and consent factors were considered. The subject site was constrained by existing infrastructure including shallow stormwater connections, a largely impervious runoff area, live surface stormwater storage to provide pre and post development peak flow neutrality and the in-ground structures needed to be designed to withstand very high wheel loadings.

Limited approved treatment options were available to treat the key contaminants present including a high hydrocarbon and heavy metal loading. Contaminant design loading rates for such activities were not well defined. The design process at the time was prescribed by ARC TP10 as a physical treatment train sized to store and treat the resulting design storm water quality volume from the catchment area.

These challenges were successfully overcome through a collaborative approach to design and development of the stormwater treatment train between consultant and supplier.

This paper presents the options assessed for the stormwater treatment train, design issues that were addressed to integrate the stormwater treatment train with the site and compliance constraints, and reports on the treated water quality.