Wetlands and constructed lakes are often seen as the 'fix all' for water quality. Indeed, they are often constructed to offset water quality impacts from new developments. The overarching aim is to reduce nutrient impacts and stop harmful algal blooms. But are they designed effectively?

In this new open-access paper, led by PhD student Shuang Liu, UNSW Sydney researchers examined all of the existing global design guidelines for constructing shallow waterbodies and tested the effectiveness of each design factor against over 200 lakes in Victoria, Australia.

The conclusion is that the application of design guidelines based on a few simple factors does not stop a waterbody from forming harmful algal blooms. However, it was found that macrophyte cover makes a significant difference.

This research was supported by Melbourne Water through UNSW’s Nuisance and Harmful Algae’s Science-Practice Partnership.

Read the full paper.