How is turbidity measured and reported?
Turbidity, which is measured and reported in nephelometric turbidity units (NTU), is an optical measurement of water’s ability to scatter and absorb light rather than transmit it in straight lines. Turbidity levels can range from less than 1 NTU to more than 1,000 NTU. At 5 NTU water is visible cloudy; at 25 NTU it is murky.