Reduced water faecal contamination

Impact

In this context, faecal contamination refers to the presence of wastewater containing faecal matter (either animal or human).  Contaminated water often contains high levels of harmful micro-organisms and bacteria, such as faecal coliform, that may cause adverse effects in living organisms.  The decay of faecal contaminants uses dissolved oxygen and releases nutrients.  These nutrients stimulate the growth of aquatic organisms, particularly plants and algae, which in turn die and decay using oxygen.  Thus the presence of faecal contamination is often associated with a decline in dissolved oxygen levels that impacts aquatic fauna, e.g. fish kills.       

Suggested indicators: Faecal coliforms in water+
Reduced water faecal contamination may be associated with:
Potential associated impacts Suggested indicators+
Reduced water nutrient load
  • Nitrates in water
  • Phosphates in water
Reduced potential for algal blooms
  • Microalgae in water
Increased dissolved oxygen levels
  • Dissolved oxygen
Changed abundance fish and invertebrates
  • Fish
  • Aquatic macro-invertebrates

Changed health of terrestrial fauna that rely on water source
  • River & wetland fauna
  • Native land fauna
  • Exotic pest fauna
Changed vegetation (aquatic and terrestrial) composition and condition
  • In-stream habitat
  • Impacts on native vegetation
Reduced shellfish contamination

+ Descriptions of indicators (PDF, 76K)* provides a brief description of each indicator including techniques and purpose.

* Requires Adobe Reader

Last updated 7 September 2010

Land Manager's Monitoring Guide