USA Volunteer Water Monitoring Network

Bacteria Monitoring


Question 1: Does anyone know of an easy to use bacteria sampling protocol that could be used by trained volunteers?

Question 2: Is anyone using enterococci as an indicator species for monitoring ambient water?

Question 1

Date: Thu, 18 Sep 2008 10:58:41 -0400
From: Gracia O’Neill


Does anyone have any recommendations for an easy to use bacteria sampling protocol that could be used by trained volunteers?

We run an advanced volunteer benthic sampling program in western NC, that partners with a university-run chemical sampling program, which provides date directly to our state water quality agency. Therefore we are looking for an inexpensive and easy to use, yet accurate protocol. We have access to e-coli (not total coliform) incubators, but no other supplies at this time.

Are there any recommendations on whether to sample for e-coli vs. total coliform?



Gracia O’Neill
Assistant Director
Clean Water for North Carolina
29 1/2 Page Ave.
Asheville, NC 28801
(828) 251-1291

Responses to Question 1

Date: Fri, 19 Sep 2008 02:24:19 -0700 (PDT)
From: Kimberly Rinard


Check out the 9223 Collilert Total Coliform methods. It requires minimum labor/training regarding staff as you collect your sample in a sterile 125ml bottle then add a packet. Mix the packet in the sample according to directions, then incubate for “x” hours(pretty sure it is 18hrs) The QT method is typically used for “raw” waters such as surface waters(lakes, streams, ponds etc) or untreated drinking water wells(pre chlorination) The QT method will also allow you to get a colony count.

The 9223_PA method is typically used for chlorinated waters(drinking water) where the only result needed is absence/presence . The PA method will also allow you to do E Coli on the same sample.

Any bacteria present in your sample will generate a gas thru a fermentation process as they react/consume the stuff in the packet that is added to the sample. Total Coliform Results are determined by the presence of a color change. The Collilert method will also allow you to do E Coli on the same sample as, a sample positive for E Coli will change color under UV light.

I know many town beaches/state programs require the 1103.1 Beach method for E Coli but I am not familiar with how it is run. The other methods out there are 9222B Membrane Filtration for Total Coliform, and 9222D Fecal Coliform, 9215(E?) Heterotrophic Plate Count

Pay careful attention to samples that are turbid/cloudy as this will affect the interpretation of the color change after incubation. Dilutions should be run whenever necessary, especially during times of high runoff, to avoid the “colonies too numerous too count” results.

Good luck and feel free to write back!

Kim Rinard
Granby, Mass


Date: Fri, 19 Sep 2008 08:41:24 -0400
From: Ann Reid

Check the Volunteer Monitor issue on bacteria…

Date: Mon, 22 Sep 2008 13:58:08 -0400
From: Kirk Barrett

We use coliscan easygel (see )

in our program ( ).

They are easy to use. it will give you both e coli and total coliforms.

Sometimes it’s hard to tell whether to classify a colony

as purple (e coli) or not. The other problem is that you don’t know exactly how much

inoculum to use a priori, so you probably should try multiple volumes.

If you use 3, it comes out to be ~$5/test.


How are you going to get the samples to the incubators?



Kirk Barrett


Dr. Kirk R. Barrett, PE, PWS, Director, Passaic River Institute

Montclair State University, 1 Normal Ave. ML 116, Montclair, NJ 07043

phone: 973-655-7117 email:



Date: Mon, 22 Sep 2008 13:30:38 -0700
From: Eleanor Ely

Hello Gracia,


Sorry for the delay in responding; I have been out of town. Hopefully by now you have found the Winter 2006 issue of The Volunteer Monitor, with many articles on bacteria testing. The Summer 2008 issue has a follow-up letter to the editor on one of the methods (MI agar). Both can be found


Good luck!



Eleanor Ely

Editor, The Volunteer Monitor Newsletter

50 Benton Avenue

San Francisco, CA 94112


Date: Tue, 07 Oct 2008 16:27:35 -0500
From: Kris Stepenuck

Hi Gracia

We did a three year study in six states in the upper Midwest and came up with a few methods that were particularly volunteer-friendly – some of which have already been mentioned (i.e., Coliscan Easygel), but there’s also 3M Petrifilm.  66% of our volunteers liked that method over the Coliscan Easygel because they had a hard time differentiating between blue and teal colonies in the Easygel method.  Though, the 3M method isn’t EPA approved for water testing, it did have the statistically strongest relation to state lab methods for assessing E. coli bacteria in streams in our study.

Here’s a website with our methods manual and other project information:

Kris Stepenuck

Question 2

From: Eleanor Ely
Sent: Tuesday, January 17, 2006 4:24 PM
To: Volunteer water monitoring
Subject: [volmonitor] enterococci, anyone?

Dear friends,

I would be interested in hearing from anyone who is using enterococci as an indicator species for monitoring ambient water (including recreational waters). What analytical method are you using? Is the analysis done by volunteers, by program staff, or at an outside laboratory?

Thanks a lot!


Eleanor Ely
Editor, The Volunteer Monitor Newsletter
50 Benton Avenue
San Francisco, CA 94112

Responses to Question 2

From: Sumner, Sara []
Sent: Wednesday, January 18, 2006 5:55 AM
Subject: RE: volmonitor digest: January 17, 2006

Hello Ellie,

I was forwarded your message by our Volunteer Lake Assessment Program
Coordinator.  I coordinate New Hampshire’s Beach Inspection Program.
Currently, we use Enterococci as our recreational water standard for
marine waters.  We use EPA’s 24 hour Method 1600 for Enterococci.  This
is also a membrane filtration method.  See the link below.

Previously, we employed the 48 hour method.  We receive funding from EPA
based on the Beaches Environmental Assessment and Health Act (BEACH)
Grants.  Due to the funding and quality assurance requirements, we now
use the 24 hour method mentioned above.

We also have purchased the IDEXX Enterolert equipment.  The problem we
have is ordering media and assuring the media will be delivered on time.
Our QAPP will soon go back for review so we have the option of using
IDEXX when we are waiting for media delivery.  Right now, we are not
making an official switch to the IDEXX method.

Our standard operating procedure for the analysis of Enterococci
includes the 48 and 24 hour methods, as well as the IDEXX method.  The
IDEXX Enterolert instruction brochure and MPN chart are referenced in
the SOP.  I do not conduct the analyses myself, so I’m not sure if our
laboratory made modifications to the method.  We use our in-house state
laboratory for all analyses.  They are NELAP certified.  We do not use
volunteers for analysis, but do use volunteers for sample collection.

As I mentioned previously, we receive BEACH Act grant funding.  Many
states use Enterococci as indicators for recreational waters.  You may
want to contact the Grant Coordinators or Regional Coordinators.  See
the link below:

I hope this has been helpful.  If you have additional questions, please
let me know.

Thank you,

Sara Sumner
Beach Program
New Hampshire Department of Environmental Services
Watershed Management Bureau
29 Hazen Dr., PO Box 95
Concord, NH 03302-0095
Phone:  603-271-8803
Fax:  603-271-7894
Subject: RE: enterococci, anyone?
From: “URI Watershed Watch”
Date: Tue, 17 Jan 2006 17:33:00 -0500
X-Message-Number: 2

We have been running enterococci analyses for a couple of years in the
URI Watershed Watch laboratories on volunteer collected samples using
Standard Method 9230 C – Membrane filtration for members of the enterococci. This
requires a 48 hour incubation, in comparison to our membrane filtration
for fecal coliform and E. coli, which leads to scheduling and reporting. In
addition as many of these samples have also been analyzed for fecal
coliform and E.coli, it has been interesting figuring how to answer the question
“is it safe to swim in my lake/river/beach?” Often that has depended on
which indicator you wanted to use – ugh!

We just purchased an IDEXX sealer and accessories, and are about to
embark on the Rhode Island Department of Health preferred method Enterolert
method, which promises reduced labor along with only a 24 hour incubation, but
will also mean amending our laboratory quality assurance project plan
(another ugh!)

I am very interested in the experiences of others with the IDEXX system
– and particularly interested in receiving copies of SOPs for those

Thanks, Elizabeth Herron
Program Coordinator
URI Watershed Watch
Phone: 401-874-4552
Fax: 401-874-4561


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