Think about backpacking in the Sierras or our coastal range. How may bears, horses, deer, birds, etc. urinate and defecate around water? Who has used this water for swimming, washing, cooking, and drinking.
The rivers, lakes, and ocean also have birds and mammals doing their thing nearby or in it.
Does the fecal coliform or enterococcus groups differentiate between humans, sea lions, birds, harbor seals?
Did the person sampling just take one sample using a pole to dip. Perhaps getting some surface water where a sea lion has just pooped nearby?
I wonder sometimes. I know if it is over the limit they resample. But is just one near shore grab once a month good enough for a representative water sample. If they sampled tomorrow, would it still be elevated?
