Accurate Rapid In-Situ Measurement of the Microbiological Impact of Pollution Sources

Advances in Field Sampling, Measurement, and Sensor Technologies
Oral Presentation

Prepared by , J. Wong
Phenomenex Inc, 411 Madrid, Torrance, CA, 90501, United States


Contact Information: d.angelescu@fluidion.com; 626-765-5580


ABSTRACT

We present a novel field methodology for the accurate and rapid in-situ determination of the microbiological impact of both localized and diffuse pollution sources. Understanding how various types of microbiological pollution may affect recreational waters usually relies on hydrodynamic models coupled with rough estimates of source concentrations. Such models can provide reasonable insight into the dynamics of a pollution event but are specific to a given area, which is uniquely affected by local tides, currents, wastewater infrastructure etc. The logistics required to probe the predictions of such models in-situ is particularly complex and costly, and therefore rarely implemented in practice. The methodology presented in this paper represent, in our opinion, a major step forward towards accurately assessing the actual microbiological impacts for a wide range of pollution events, using novel automated sample collection and measurement technologies that greatly simplify the complexity of such field studies.

Multiple monitoring campaigns will be presented, both from the Greater Paris area and from Southern California. Dilution factors of known discharges (e.g. stormwater outflow, wastewater treatment plant effluent, boat sewage etc.) as well as E.coli concentrations were measured in the receiving water body using fluorescent tracer concentration measurements on sample time series collected manually and using an automated aquatic drone. The remotely-controlled drone was capable of acquiring grab samples to be returned to shore for analysis, or of performing autonomous on-board measurements. Rapid E.coli concentration measurements were performed using ALERT instrumentation from Fluidion, using both portable and in-situ sensors installed upstream and downstream of the pollution source under study, to quantify both the source term and the actual impact over the existing E.coli background. All instruments operated autonomously on battery and with data transmission to the cloud, thus obviating the need for an actual laboratory.