E. coli pollution in rivers is primarily caused by faecal contamination from sewage, agriculture, and urban runoff. Its presence signals a risk to human health and aquatic ecosystems.

Here’s a concise summary of the causes and impacts:

💩 Causes of E. coli in Rivers

• Sewage discharges: Treated and untreated sewage, especially from combined sewer overflows (CSOs), can release high levels of faecal bacteria into rivers during heavy rainfall or system failures.

• Agricultural runoff: Manure from livestock and slurry spreading on fields can wash into rivers, particularly after rain, introducing E. coli and other pathogens.

• Urban runoff: Stormwater drains can carry pet waste, bird droppings, and other contaminants from streets and parks into waterways.

• Septic tanks and private treatment systems: Poorly maintained or leaking systems can leach bacteria into nearby streams and rivers.

⚠️ Impacts of E. coli Pollution

• Human health risks: High E. coli levels indicate faecal contamination, posing a risk of gastrointestinal illness to swimmers, paddlers, and others in contact with the water.

• Bathing water quality: Rivers with elevated E. coli often fail to meet the standards for designated bathing waters, limiting recreational use and public trust.

• Ecosystem stress: While E. coli itself doesn’t harm aquatic life directly, its presence often correlates with broader pollution issues (e.g., nutrient overload, low oxygen) that degrade river health.

• Regulatory and reputational consequences: Poor water quality can affect local economies, tourism, and community wellbeing—especially in areas seeking bathing water designation or river restoration.