Self contained towable underwater system for environmental monitoring

To fulfill the need for environmental data required for the establishment of rational water quality standards, an integrated underwater environmental monitoring system has been designed and tested. This system consists of a vehicle that houses a number of electrochemical and electrophysical sensors and a recording system. The environmental parameters measured by the monitor are: depth, temperature, conductivity, dissolved oxygen, pH, oxidation-reduction potential, sulfide ion activity and ambient light. The vehicle can be 1) towed behind a boat at different depths or at constant distance from the bottom or 2) operated by a diver. The entire monitor is self-contained and does not require any external power supply during operation. The data are recorded on 16 mm film in alphanumeric form. The computer-performed data reduction consists of 1) correcting each parameter value for electronic and sensor drift and for temperature, 2) transforming these values into more manageable units by means of calibration curves or definition formulae and 3) presenting the data in plotted form as a function of location for easy interpretation.