Have you ever had the visibility in a swim drop to a few centimeters? Has it ever gone a bit brown? Perhaps you've ended up swimming through sewage!

This happened to Dr. Ian Wright in the 90s, and is likely to have happened to any ocean swimmer who was swimming off the coast of Sydney in that period. Ian is a keen ocean swimmer and a senior lecturer in the School of Science and Health at Western Sydney University, whose research interests include freshwater ecology, water chemistry and water pollution. We chatted about the poo problem at Sydney's beaches.

Songs in this episode - all licensed under a Creative Commons License:

• Plume - Kubbi

Image from eutrophication&hypoxia

There's also a quick Kath and Kim clip in there at the end #lookatmeme