Performance monitoring of artificial wetland· constructed/or contaminant removal from urban stormwater and agricultural runoff has not been comprehensively undertaken, particularly in Western Australia. Evaluation information from constructed wetland in a variety of settings is required to allow informed decisions to be made on the effectiveness of’ their design and operating principles.
A performance monitoring program has been established at a rural constructed wetland receiving runoff from 150 ha of beef grazing land between Albany and Denmark on the south coast of Western Australia. The performance monitoring program aims to scientifically determine how effectively the wetland retains the contaminants it is designed to treat, whether design modifications may be required and to assist informed decisions on whether constructed wetlands are an appropriate strategy to treat rural runoff in this area. In addition, the program will enable development of a cost-effective long-term monitoring program for the wetland generic monitoring programs based on manual grab sampling suitable for other constructed wetlands.
The overall wet/and monitoring program has several components and this paper will concentrate on detailing the inflow, outflow and storm-event-bypass nutrient and sediment flux monitoring. This data will allow determination of the wetland’s Contaminant Removal Efficiency (CRE).
Flow rates are measured using either calibrated weirs or an acoustic Doppler depth-velocity logger. Water quality variations are determined by a combination of grab sampling, flow stratified autosampling and continuous turbidity sensing.