Kid’s Riddle: What kind of fish can’t swim? (Answer at the end.)
In 1969, record numbers of fish kills were reported - 41 million fish died. Problems like this spurred passage of the Clean Water Act in 1972.
The Clean Water Act (CWA) is the cornerstone of surface water quality protection in the U.S. It is also one of the nation’s most successful environmental laws. The statute has prevented billions of pounds of pollution from spilling into our waterways. In 1972, only 36% of the country’s lakes and rivers were safe for swimming. After thirty years, more than 66% of waters are safe enough for fishing and swimming. (Sources: EPA, Sierra Club, PBS) However, water pollution remains a serious threat.
The CWA requires a variety of measures to reduce polluted discharges, finance municipal wastewater treatment facilities, and manage runoff. (Runoff is water that travels over the land before entering water bodies like streams and lakes). These controls are designed for "the protection and propagation of fish, shellfish, and wildlife and recreation in and on the water.” In other words, the goal to keep water clean enough for wildlife to live in, and for human aqua-fun. Two of the CWA criteria are whether water is considered ‘fishable’ or ‘swimmable.’
When is water considered un-fishable? Two categories are when (1) fish have so many toxic substances in them that they are unsafe to eat, or (2) water quality is so bad that fish populations are significantly reduced or absent.
For example, in certain sections of the Housatonic River in western Connecticut, PCBs levels in fish tissues are considered unsafe for eating. PCBs are man-made chemicals once used in electrical transformers by companies like General Electric in Pittsfield, MA. Once released into the river, PCBs get into sediment. Then they can bio-accumulate in fish tissues, when big fish eat little fish that eat critters that live in the sediment. Because PCBs can cause cancer in humans, eating fish caught in the Housatonic River is not advised by the CT Department of Public Health. Likewise, a similar warning is issued about eating fish caught in Versailles Pond, Paper Mill Pond and connecting section of the Little River in Sprague, due to past industrial discharges. (Not to be confused by the Little River in Woodstock and Putnam – there are many different ‘Little Rivers’ around.) For more information, see the CT DPH website at www.ct.gov/dph.
Un-fishable also happens when physical and chemical conditions in the river are altered so they no long support aquatic life that should be there. Some fish, like trout, are sensitive to water temperature. If the water gets too warm, as it can when all the shade trees along banks are cut down, trout do not survive. When too many nutrients get in the water, algae can flourish. As the dead algae decomposes, it uses up dissolved oxygen in the water. Without enough oxygen to breathe, fish die, as do underwater insects they feed on.
A ‘rapid bio-assessment” can be done to help figure out whether water quality is impaired for aquatic life. Certain insects are used as indicators, since it is easier collect insects that fish feed on than it is to catch the fish themselves. The Quinebaug-Shetucket Heritage Corridor supports a volunteer water quality monitoring program in our area. Every day people are trained to sample their neighborhood streams for these ‘indicator’ insects.
In 2007, 18 samples were collected by volunteers and sent to the CT DEP. The results will be used in their water quality assessment program. While the technique does not tell us everything we need to know about river health, it does send up a red flag if key indicator species are missing, so follow up investigations can be conducted. If you are interested in volunteering for the water quality monitoring program, contact Jean Pillo at 860.928.4948. It is a fun way to relive your childhood by playing in the brook, but with a noble purpose.
A long list of “impaired” waters that do not meet water quality standards can be found on the CT DEP website. The list is updated every two years. For example, Muddy Brook and North Running Brook in Woodstock are on the list for habitat for fish, other aquatic life and wildlife. Next week’s column is about swimmable waters.
Riddle Answer: A dead fish!
See Part II