Water Quality Monitoring

Water quality measurements are performed for water in streams, rivers, lakes and in groundwater systems. There are different parameters that can be measured and used as indicators of water quality, for example electro conductivity (EC), acidity or alkalinity of a solution (pH) or dissolved oxygen (DO). Water depth, flow and temperature can add valuable insight into water quality. For that purpose 6542 hydrostatics depth probe or 6526 Starflow instrument can be added to a water quality measurement station.

Application Detail

Unidata supplies a wide range of water quality systems. In the example shown in the illustration, water conductivity, temperature, pH, dissolved oxygen and water depth are measured and data stored and wirelessly transmitted by a Neon Remote Logger.

The water conductivity probe 6536P-2 is connected to the 6536E Water Electro Conductivity instrument via an SDI-12 bus. The 6536E Conductivity instrument runs local scheme to collect conductivity reading every 5 minutes. Neon Remote Logger is set up to collect / log readings from conductivity instrument, pH probe, dissolved oxygen probe and hydrostatic depth probe every hour and to transmit this data to central Neon server every 4 hours.

Ultra-low-power consumption of this system set up is ideal for remote, unattended operation. These instruments and logger will operate for up to 2 years using a small lithium battery package. Installing the Neon Remote Logger enables you to monitor and modify / change data acquisition and check the health of the site, all from a remote location using a web browser anywhere in the world.

The choice of telemetry option would be based on cellular coverage in the measurement area and costs associated with reporting the data back. Satellite services for these applications have reduced in price over the last 5 years, so satellite services are a reasonable option for such measurement stations.

The systems can be powered using lithium battery packs, or a small solar panel and battery. Like all Unidata systems you can connect many other sensors to the standard system. If water quality measurements are done in relatively shallow waters, 6542 hydrostatic water depth probe can be replaced by 6526 Starflow instrument. Starflow will measure depth of water as well as velocity and rate of flow.