The River Thame Conservation Trust (RTCT) are looking for volunteers to help them assess the health of Aylesbury's waterways.
They have launched a campaign to clean he rivers and streams in Aylesbury, called the ‘Outfall Safari’.
Tim Longstaff, the project manager, said: "Did you know the drainage system in Aylesbury is formed of two sewers?
"One is the Surface Water Sewer - conveying rainfall from roofs, roads and other hard surfaces straight into the nearest river.
"The second is the Foul Sewer - transporting wastewater from toilets, showers, washing machines etc. to a sewage treatment works to be treated before being released into a watercourse.
"Unfortunately, sometimes appliances, such as a toilet, can end up misconnected - meaning they have been incorrectly plumbed into the surface water drainage system. This means that foul water is flowing straight in to rivers untreated, instead of to the sewage treatment works.
"These misconnected outfalls often go unnoticed and can become a chronic source of pollution.
"The Outfall Safari method involves systematically surveying the entire length of a river to identify and locate these misconnected outfalls. This allows the pollution to be reported to Thames Water and the Environment Agency so that it can be tackled."
RTCT are hosting a training day for those interested in helping out on Monday March 18 at the Bedgrove Community Centre
The training event will fully explain what's involved with taking part in an Outfall Safari, how to identify misconnected outfalls and how to record and score pollution.
For more information, and how to register, visit: https://www.eventbrite.co.uk/e/outfall-safari-training-tickets-56498772349?aff=efbeventtix&fbclid=IwAR0cn-bV-IbSgxwpw_mvvOlxYrHDOJ67P1UuogBDaF-7MuF-wQSETO5g_v4
Tim added: "We don't know is Aylesbury's waterways are clearn or dirty, but we do know we need your help to find out!
"Once you've been trained, you can get out investigating using the app we will train you how to use.
"Refreshments will be provided but please bring a note pad and pen with you to take notes.
"We hope to see you soon!"