Highlights of Burlington Storm Water Runoff Data 2003

Bacteria results in MPN per mL
MPN = most probable number of colonies

Real-time data on Burlington runoff is available from an autosampler located in the College St. storm drain. In addition, samples are collected from this site for later analysis (as shown in the tables above). Also check out the data on total suspended solids (TSS) and volatile solids and total phosphorus.

What do these numbers mean?

Each number in the table above is the most probable number of coliform colonies or E. coli organims per 100 mL of storm water. According to Vermont standards for E. coli, when the test result at a public swimming area is 77 or less, it means that the water is considered suitable for swimming. A result greater than 77 means that the water is not suitable for swimming. The results above are only representative of the storm runoff at each site. The swimmability of the lake can not be determined from these results since the runoff water is diluted when it is mixed with the lake water.

Total coliform bacteria are a collection of relatively harmless microorganisms that live in large numbers in the intestines of man and warm- and cold-blooded animals. A specific subgroup of this collection is the fecal coliform bacteria, the most common member being Escherichia coli. These organisms may be separated from the total coliform group by their ability to grow at elevated temperatures and are associated only with the fecal material of warm-blooded animals. If E. coli bacteria are detected in the water, other disease-causing microorganisms may be present as well.

The presence of coliform bacteria in aquatic environments indicates that the water has been contaminated with the fecal material of man or other animals. At the time this occurred, the source water may have been contaminated by pathogens or disease producing bacteria or viruses which can also exist in fecal material. The presence of fecal contamination is an indicator that a potential health risk exists for individuals exposed to this water. Fecal coliform bacteria may occur in ambient water as a result of the overflow of domestic sewage or nonpoint sources of human and animal waste. This is a good reason to Scoop the Poop.