Water Testing & FAQs


The E. coli and fecal coliform levels in Crystal Lake are within normal limits, according to the most recent test results. Samples are collected weekly, usually on Wednesdays. Results will be posted when available -- usually on Fridays.

A previous water sample taken Wednesday, July 1, exceeded acceptable bacteria levels at a freshwater beach. We test for E. coli and fecal coliform. The accepted level of E. coli for a single sample is 235 cfu/100 ml or below. The accepted level of fecal coliform is 200 cfu/100 ml or below. (CFU stands for colony-forming units, the unit of measure used for samples like this.)

Marine and freshwater beach guidance (MDPH)

Updated July 31, 2020



Crystal Lake

July 1

Crystal Lake

July 3

Crystal Lake

July 8

 Crystal Lake July 15

 Crystal Lake

July 22

 Crystal Lake July 29

E. coli

235 cfu/100 ml

Above 1600 cfu/100 ml

72 cfu/100 ml

136 cfu/100 ml

 10 cfu/100 ml  20 cfu/100 ml 108 cfu/100ml 

Fecal Coliform

200 cfu/100 ml

Above 1600 cfu/100 ml

88 cfu/100 ml

128 cfu/100 ml

 15 cfu/100 ml  48 cfu/100 ml  128 cfu/100 ml



Frequently Asked Questions Coming Soon 

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