The MPCA has been monitoring water quality for five decades. While digging through old newsletters, we unearthed an interesting water monitoring relic.

Then
Circa 1970 – MPCA’s newest water monitoring machine
The custom-made equipment monitored temperature, conductivity, pH, and dissolved oxygen in a lake or river. It was able to do this by pumping lake or river water through tubing located in the bottom drawer. Then the electronic sensors continuously displayed data both on the needle gauges set in the middle drawers and on the graph paper (top drawer).
If the machine sensed something, it would draw a bottle of water for laboratory analysis and (assuming there was a phone hook-up) call for someone in the office to come and get it.
“They were used in Cedar River south of Austin and one on the Red River,” says Marvin Hora, retired MPCA manager. “Quite advanced for the time with the automatic sampler and telephone call in. However, they required a lot of maintenance and kid glove care for the probes and sensors,” Hora added.
Now
Today we use a hand-held device, known as a Sonde. “It weighs about 10 pounds,” says Jordan Donatell, MPCA Water Quality Monitoring Unit. The device is placed in a lake or stream for two weeks where it continuously collects data every 15 minutes. “When the Sonde is retrieved, the information is transmitted via blue tooth to a handheld device which is then connected to a desktop computer for efficient analysis.” Donatell added.
Monitoring our lakes and streams is tied to the 1972 Federal Clean Water Act. The act requires states to adopt water quality standards to protect their water resources. The MPCA provides information to assess — and ultimately to restore or protect — the integrity of Minnesota's resources.
Learn more about our water monitoring efforts.
