Kid’s Riddle: Why did the teacher jump in the lake? (Answer at the end.)
In 1969, bacteria levels in the Hudson River were at 170 times the safe limit. After 30 years of regulation, water pollution is still a serious problem in the U.S.
Back in the day when Doug Zimmerman played Little League for Cy’s Parking Lot in East Hartford, fans had to hold their noses and no one would retrieve fly balls that landed in the Hockanum River because of the floating sewage. Fortunately, today most of the water in northeastern CT today is good quality. Last week’s column talked about conditions that impact the “fishable” (aquatic life support) functions of water. Now let’s look at the “swimmable” part of the Clean Water Act.
Under this law , water is considered safe for recreational contact or “swimmable” (activities in or on the water likely to result in some of it getting in your mouth) if the water is tested and the number of colonies of certain bacteria are below a specified threshold.
One common type of bacteria used as an indicator is E. coli. These bacteria are a normal thing in the intestines of warm-blooded animals like humans. As a matter of fact, we can’t live without them. E. coli feeds off the food we eat, and then produces a waste product more commonly known as Vitamin K, which we absorb through our intestinal walls. This type of bacteria is also found in dogs and other mammals, as well as waterfowl like geese.
Most strains of E. coli are harmless, but there are some that can cause serious illness like diarrhea and food poisoning. People can be exposed to raw sewage by swimming and boating in contaminated water. When E. coli is found in the water, it may indicate that there is sewage treatment plant malfunction or a faulty septic tank. Besides being yucky, raw human sewage can contain many other human pathogens like viruses and intestinal worms that can cause serious illnesses like cholera, dysentery, infectious hepatitis, and gastroenteritis. Sensitive populations such as children, the elderly, and those with weakened immune systems are at a higher risk of illness. This is why you should never drink untreated river water.
While there is no easy way to check for all these awful disease vectors, E. coli is fairly easy to measure. Water is collected and brought to a lab, where it is carefully applied to a glass dish containing stuff the bacteria grows best on. In a matter of hours, individual bacteria multiply into colonies that can be seen under the microscope and counted. If the number of E.coli are below a certain standard, the water is classified as safe to swim in. Above that number, and beach closure signs go up. (Signs are required at swimming beaches, but not on rivers.)
This testing method requires special equipment and is somewhat labor intensive. Therefore, it is not routinely done unless the water is used as a swimming beach. It is also only done during the time of year when swimming is common. The State Dept. of Public Health tests the water at the beaches managed by the State. Towns hire the local health department (like the Northeast District of Health in Brooklyn) to test local public access beaches. Some private lakes are tested, others are not - contact your local lake association for more information.
The CT DEP collects water quality data on rivers, including bacteria sampling. With about 6000 miles of rivers in the State, they must focus their limited resources on one part of the State each year. Random samples are taken outside focus areas, but the amount of information is limited. Simple E. coli testing can not tell the difference between human and other animal sources. For example, Mashamoquet Brook State Park in Pomfret sometimes has too much E.coli at the swimming beach. The source of this bacteria is listed as “source unknown.”
A list of “impaired” waters can be found on the CT DEP website. For example, Roseland Lake in Woodstock and Mashamoquet Brook in Pomfret are on the list as impaired for recreation (due to nutrient or eutrophication biological indicators at Roseland, and E.Coli at Mashamoquet Brook.)
Riddle Answer: Because she wanted to test the waters!