|Keeping our waterways and coastal environments free of wastewater contamination is a growing problem causing many universities, governmental agencies and facilities to take notice. There is a detectable increase in wastewater dumping corresponding to the increase in human populations and densification of coastal, lake and riverine areas. An important step in mitigating or predicting harmful situations is to monitor and decrease the amount of wastewater dumped into aquatic habitats. Unfortunately, wastewater isn’t a specific material; rather, it is composed of multiple materials sometimes making it difficult to distinguish from other water types.
However, wastewater does have certain components with fluorescent characteristics and if configured correctly, fluorometric instrumentation enables users to detect wastewater even in complex mixed water systems. Optical brighteners and tryptophan can both be measured and are proxy indicators of wastewater contamination. There have been many studies correlating coliform bacterial counts with optical brighteners and tryptophan-like fluorescence can be linked to anthropogenic DOM inputs from sewage and farm wastes. Because bacterial counts are often tedious and take longer to determine, a quick measurement using fluorescence will provide real-time data on the potential contamination of a given system.
Wastewater also has certain characteristics such as high organic loading, which can result in rapid decay and production of pCO2 upwards around 10,000 ppm, for certain holding ponds. Those CO2 levels are 20x the typical CO2 levels found in natural water. If leaked into natural waterways such as estuaries, rivers, or lakes, these systems and the organisms contained within can be greatly impacted changing the dynamics or the productivity of that aquatic habitat.