Re-use of Effluent

What should you know?

This level of treatment currently allows less than 1% reuse, through a number of restricted uses. These include nurseries, vineyards, hydroponic uses, market gardens, silverculture, dust control, public reserves and aquaculture. The EPA set Guidelines for Wastewater Irrigation that cater for conditions that people must abide by if they are going to re-use treated effluent. These guidelines are in place as a result of the National Reclaimed Water Guidelines, Agriculture and Resource Management Council for Australia and New Zealand, Australian and New Zealand Environment Conservation Council and the National Health and Medical Research Council. Coming into contact with treated effluent presents a risk that needs to be reduced, or mitigated by setting guidelines that will reduce someone's exposure to the contaminants. The main concern with using recycled effluent are the health of the people and the health of the earth that receives the effluent. Secondary treated effuent contains bacteria and viruses contaminating the food chain and water sources. Contamination to land via runoff also has to be managed. Recycled effluent of Class C standard cannot be used on leaf vegetables but can be dripped into the roots of plants, such as at vineyards. The current guidelines recommend that access by humans to land irrigated with secondary treated effluent should be restricted during, and for at least 4 hours after irrigation. Signwritten notices must be installed stating that the water being used is not safe for drinking.

Volume of Re-use

Given the constraints of reuse, the percentage the demand for the water is currently very low. In Victoria only 1% of effluent from Eastern Treatment Plant is recycled each year. In relative terms, that is 34 million litres per year, the equivalent to 164,250,000,000 litres, which is less than 4 days flow. 

This is an alarming figure given the exorbitant consumption of freshwater, the recent water shortages in Victoria and the damaging effects this has on rivers and land with the decreased flow. After 25 years of discharge, the people of Melbourne would expect that the statutory water authority would have had a more efficient solution for reuse of effluent and managing our natural resources.

Powered by Taten webevolve™