Learn More: Turbidity

What does this mean?

The amount of solid particles that are suspended in water and that cause light rays shining through the water to scatter. Thus, turbidity makes the water cloudy or even opaque in extreme cases. Turbidity is measured in nephelometric turbidity units (NTU).

How are the data collected? (Methods)

Real-time water quality stations are located in 6 different locations throughout Seminole County. The instrument used to collect these data is the YSI 6600 EDS sonde. The sonde is mounted such that the bottom of the unit is located approximately 1 to 3 feet below the water surface. The instrument is either mounted to a fixed pole system or a fixed buoy that is moored within the lake or river. The units are under a maintenance schedule to ensure proper functioning of each sensor.


Not Applicable. Instrument range, resolution, and accuracy can be found under external links.

Caveats and Limitations

Because the real-time water quality data presented on the Seminole Watershed Atlas goes through a series of transfers before becoming available, there can sometimes be a time delay in presenting the data. Additionally, if the water quality stations or computers transferring the data are tampered with, this may cause problems in being able to present the data in 12 hour increments. In addition, the data do not undergo the same level of quality control as other data sets prior to being presented on the Atlas. A caveat of using near-real time data is the possibility of error. Near-real time has not undergone as many quality control procedures common to our other data sets. Therefore, occasionally due to equipment malfunction there may exist errors within the data. Every attempt is being made to mitigate these errors before they occur.