ESTABLISHMENT OF A CONSTRUCTED WETLAND AT VICTORIA MILL

摘要

Victoria Mill has four shallow ponds known collectively as Lake Harry, into which effluent from the activated sludge plant is passed for polishing prior to discharge. A section of about 5500 square metres of Pond 3 was separated from the rest by an earth bank. This section was planted with various wetland plant species in November 1993 to establish a pilot scale constructed wetland for the tertiary treatment of mill effluent. Some difficulty was encountered in establishing the plants, resulting in supplementary planting in June 1994. Influent and effluent water samples were collected for water quality analyses. In addition, preliminary microbial population data were collected prior to the initial planting, and regularly since, to monitor the gross changes in population as the wetland becomes established. The vegetation dynamics were also monitored during establishment. Preliminary results indicate that the wetland is successfully reducing the concentrations of various water quality parameters such as BOD, nutrient levels and total suspended solids.