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Rapid Waterborne Contaminant Sensing and Reporting

Published Nov. 20, 2012
ERDC Geospatial Research Laboatory researchers prepare to deploy AQUAPATH.

ERDC Geospatial Research Laboatory researchers prepare to deploy AQUAPATH.

Civil and military communities rely on potable water supplies. Besides contaminants, environmental factors along with land development practices can have significant impacts on the availability and safety of a water supply for producing potable water. Only accurate testing and monitoring and rapid reporting of waterborne contaminants can help keep communities and their potable water supplies safe.

Detects and Reports Contaminants Faster Than Any Other System

The ERDC Fluorescence Remote Sensing Lab, part of the ERDC Geospatial Research Laboratory (GRL), developed the AQUAPATH (Autonomous Querying Threat Agent Sensor for Potable Water Handling) system to source track, monitor and locate sources of water for producing potable water supplies for both military and civil communities.

AQUAPATH detects water quality parameters, including pH, conductivity, luminescence dissolved oxygen, turbidity and internal buoy temperature. It also detects waterborne pathogen indicators, such as coliforms and E. coli.

Although AQUAPATH system capabilities include reporting of water quality parameters, the unique aspect of the system is the ability to collect bacterial measurements in the field and transmit a rapid response of geo-referenced data.

Other benefits include:

  • Opto-electronic sensor in floating buoys with wireless network transmission
  • Low power, threat-agent specific, near-real time response
  • Fluorescence-based sensor with laser diode technology for contaminant detection
  • Geospatial modeling of the environment and recovery of potable water supplies by remote sensing
  • Geo-enabled data collection and storage for on-site analysis and sensor network sharing

Adapts to All Water Environments and Contaminant Concentration Levels

AQUAPATH is a biosensing system comprised of a cluster of water quality buoys. It reports in a geospatial wireless network. It uses fluorescence-based biotechnology and optical reporting as the sensor modality for detection. AQAUPATH operates in fresh water, brackish water and saltwater environments.

AQUAPATH can detect the presence (or absence) of high level contaminant concentration in less than 30 minutes. For normal traditional bacterial testing, researchers must transport water samples back to a laboratory. The reporting of results typically takes 18-48 hours or longer depending on the test methods used.

Success Stories

  • In 2009, the ERDC Fluorescence Remote Sensing Lab, in collaboration with TARDEC and Sporian Microsystems, Inc., demonstrated the first AQUAPATH waterborne pathogen detection and monitoring system in the field at Lake St. Clair, Michigan. AQUAPATH detected coliforms and E. coli in situ and reported the data wirelessly in 30 minutes.
  • As part of field testing in 2010, researchers used AQUAPTH to test a particular area of the Potomac River and Pohick Bay in Virginia downstream from a wastewater treatment facility. AQUAPATH, staged on four buoys, detected general coliforms and E.coli O157:H7 in 20 minutes at 850 CFU/100ml (concentration numbers reported from Colilert-18 Tests) and remained consistent after 2.5 hours. AQUAPATH detected the presence of contaminants 16 hours quicker than the fastest Environmental Protection Agency (EPA) test currently available (the Colilert-18 Test). There was no stormwater activity prior to running tests.
  • In 2012, AQUAPATH was field demonstrated in collaboration with the Marine Forces Pacific Experimentation Center (MEC) at Exercise Cobra Gold and Exercise Balikatan.
  • Other recent work includes biological agent detection, characterization of the systems in the field at various test and evaluation centers for environmental water quality sensing, and third-party evaluation associated with the biotechnology of the AQUAPATH system.


AQUAPATH Prototypes

Researchers can apply AQUAPATH prototypes to test fresh water or salt-water environments, wells and water supply storage systems. The latest integration of the AQUAPATH biosensing biotechnology also incorporates an in-line water treatment system.

Novel Wireless Network Capabilities

Military, intelligence and civil operations can use AQUAPATH for value-added monitoring for remote sensing. From a geospatial standpoint, AQUAPATH users can readily augment current monitoring capabilities of water supplies. GRL researchers continuously investigate new targets of interest for sensing and monitoring within current infrastructures, including increased sensing range in the field and in actual water treatment systems.


Support technologies for AQUAPATH at the ERDC Fluorescence Remote Sensing Lab include development, bacterial target characterization/evaluation, and wireless test and evaluation of the various prototype systems. Currently, the systems have been tested to perform functionally at a distance of up to 2000 meters. Future upgrades will extend the reporting distance and will allow data reporting through cellular phone applications to the operator. The AQUAPATH system is adaptable for total coliforms, salmonella, E. coli O157:H7, Vibrio cholera and any pathogen for which an antibody is available. Other specifications include:

  • Detection response time approximately 20 minutes to 2 hours
  • Signal conditioning circuits and sensor control firmware/hardware allows sensor to act autonomously
  • Submersible custom housing for optical sensors, including a pump for stagnant water applications
  • Communications buoys capable of reconfigurable local sensor networking and satellite data transmission


Future Efforts for the AQUAPATH System

AQUAPATH is currently being tested and evaluated for methods compliance with the EPA Standard Methods and the Army Test and Evaluation Command Methods. It is also being developed into a biosensing system for monitoring water quality via an in-line water treatment insert and in conjunction with portable reverse osmosis systems used in military and civil applications. Based on AQUAPATH’s architectural wireless network design, future efforts will focus on adapting additional sensory modules for monitoring of additional environmental contaminants in air as well as water from a geospatial remote sensing perspective.

For more information on AQUAPATH, visit the ERDC Fluorescence Remote Sensing Lab online.

 ERDC Points of Contact
Questions about AQUAPATH?
Contact:  Dr. Clint B. Smith
Phone:  (703) 428-6789
Updated 25 August 2020