H2NOW is evaluating the Proteus multiprobe technology for measuring fecal coliform levels in an urban waterway setting. This device uses a novel tryptophan-like fluorescence (TLF) sensor, along with already proven temperature and turbidity sensors to estimate microbial levels in real-time. Proteus Instruments applies an algorithm that compensates TLF readings for the effect of changing temperature and uses turbidity as a model input to estimate the number of either total or fecal coliform bacteria. The model parameters are calculated on the basis of observed correlation of sensor readings to microbial test results and entered directly into Proteus software.

The multiprobe itself is made with stainless steel to ensure durability and utilizes a wiper arm to clean the optical sensor surfaces before each reading is taken. In H2NOW, Proteus sensor readings are obtained every 15 minutes and transmitted immediately.