RE: Swimmers should take E. coli warnings seriously

["Alm, Elizabeth Wheeler" <alm1ew@cmich.edu>]

I think the situation is probably unique for each beach. You have to consider the beach geography, hydrology, prevailing wind directions, currents, surrounding land use, what the potential sources may be,  whether or not there are point sources, etc. It's not a one-size fits all.  And with respect to E. coli as an indicator, also understanding that E. coli is a very diverse species and not all strains have the same source, correlation with gut pathogens, potential for persistence, etc.  I think E. coli probably works as an indicator when there is a point source in a nearby location. As the situation for each beach is likely unique, controlling fecal contamination, mitigating health risks, remediation solutions, etc. will also be beach specific. Not an easy solution as many would hope for.
 
Elizabeth Alm, Ph.D.
Professor, Microbiology
Central Michigan University

________________________________

From: Kuntz, Joseph [mailto:JKuntz@ci.stamford.ct.us]
Sent: Wed 7/18/2007 11:57 AM
To: Alm, Elizabeth Wheeler
Subject: RE: Swimmers should take E. coli warnings seriously



Still more info concerning all of this ...
perhaps the most difficult thing to deal with is the universal standard, 256 colonies/ 100 ml for E. Coli and 104 Colonies/ 100 mL for enterococcus, especially when you see all the ways an indicator organism can proliferate in the environment.
We have a database that contains fecal coliform data from 1985 and enterococcus data from 1989.  Using that as a tool, I can safely say that for us on the shores of Long Island Sound, the standards work.  Without any environmental / weather issues the water quality is exceptional.  Wind and rough seas (okay it is only the sound so it is not that bad) might resuspend some bacteria, but not over the standards set.  A good 1 inch rain, without much wind will through the counts over those limits for 24 hours.  This is because Stamford is urban and run-off is not treated.  When the rains become greater than 2 inches we can expect problems in the form of sewage grease from CSO's of neighboring towns within a few days depending on the wind direction.  It is only when this stuff washes on shore do we find a problem at the beach.
Taking bacteria counts as a straight number is not okay unless you have a good history of what they mean.  Check out some of our history
http://www.cityofstamford.org/content/25/52/140/214/364/402/443/1384/1388/default.aspx



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