Recent testing along the Muddy Branch

Saturday, November 9, 2013 - 11:42pm

Here are the results of our recent bacterial monitoring on the Muddy Branch.  Dennis drew samples on three different dates from three different locations on the stream:

"9/10/13 - from a site roughly 150 meters south of Rt 28;  the air temperature was 90 degrees; 5 ml of stream water mixed with bottle of Coliscan Easygel solution, plated and incubated at room temperature for 48 hours; photo attached as "Coliscan 1";  I counted 9 blue colonies and 2 large red and many small red growths; there were also roughly 25 brown or opaque colonies; and a distinct odor;  not sure how to interpret the red spots - they were definitely red and not pink; according to Coliscan, general coliform bacteria should appear as pink and fecal coliform as blue;"
Coliscan 1
9/18/13 - NOTE - there was a locally heavy rainstorm in the area on 9/12/13;  the sample site was at the point where the Muddy Branch crosses under Quince Orchard Road (RT 124); the air temp was approximately 72 degrees; 5 ml of sample water mixed with Coliscan Easygel and incubated at room temperature for 48 hours;  photo attached as "Coliscan 2"; I counted 3 blue/green colonies, 2 large pink and over 30 pink growths with 6 large brown/opaque colonies;  again a distinct odor was noted; "
Coliscan 2
9/20/13 - the sample site was at the boat ramp at Pennyfield Lock, just off the parking lot;  air temperature was 80 degrees; 5 ml of sample mixed with Coliscan Easygel, plated and incubated at room temperature for 48 hours;  photo attached as "Coliscan 3"; many large pink and many more small pink colonies were counted as well as 5-6 blue colonies;  distinct odor;"

Coliscan 3

We can now say that the Muddy Branch tests positive for bacteria.  What's interesting is that the level of contamination was relatively constant before and after the downpour on 9/12 and was present at all three sample sites.  The dramatic increase in general coliform bacteria followed the rainstorm and was still very high more than a week later.  We are going to continue this effort and start sharing the results with those interested.