What causes E. coli in water?

It's caused by poo! While some areas have sewer overflow that has issues with human waste getting into the waterways, other areas have problems with geese, ducks, and other animals, all of which can have an effect on e.coli levels. You can get very sick if you consume water that's contaminated.

How is it measured?

Ecoli is usually measured in a lab. It usually takes 24 hours to get your results, since the culture needs time to grow. The lab gives you special containers and teach you how to make sure your sample isn't contaminated. They're measured in Colony Forming Units per 100mL (CFU/100mL).

UK: What do results mean?

  • 0 - 1,000 = Go, relatively safe for human contact
  • > 1000 = Caution, increasing risk as it increases

CANADA: What do results mean?

  • 0 - 200 = Green (go, relatively safe for human contact)
  • > 200 - 600 = Yellow (caution, increasing risk)
  • Greater than 600 = Red (stop, relatively unsafe for human contact)