It’s common to describe the causes of water pollution generically, by directly blaming specific categories of pollutant – fertilisers, pesticides, or petroleum derivatives, for example.
Another popular approach is to describe the point of origin of the water pollution in spatial terms.
This approach distinguishes surface run-off (water flushing out pollutants from a wide area) from point-source water pollution (pollution from an industrial discharge pipe, for example).
An alternative terminology for non-point and point source is direct and indirect water pollution.
Some analysis focuses on the direct threat to human health from disease-causing agents or soluble toxics in polluted water.
Finally, a few descriptive resources list human activities such as mining, forestry, construction and farming as causes of water pollution or may acknowledge that pets are a source of water pollution.
Sometimes these activities are described, interchangably, as sources of water pollution.
Of course, it’s helpful to categorise pollutants and their sources in a number of ways to enable detailed discussion about what to do about the problem of water pollution.
However, few answers to the question ‘what causes water pollution?’ explicitly acknowledge the fact that people cause water pollution.
Human agency may be the most understated cause of water pollution. Of course we pollute passively on a large scale, merely by using the systems set up for us to exist and thrive.
But it’s only rarely that a case turns up and gets sufficient publicity to remind us that we are also capable of repeated, conscious, large-scale water pollution.
We just don’t know how many one-off acts of conscious water pollution go undetected. And the names of convicted corporate defendants largely remain outside the public consiousness.
In the Chemetco case, executives made a series of conscious choices over a period of many years, to support mulitple conspicuous acts of water pollution.
There’s no way to prove exactly why they did this. Perhaps one of them will come forward one day and offer an explanation.
But it’s worth documenting exactly what they did, how many times, and how mindfully they did it.
Alistair Siddons is the editor of the tripflare and a member of the society of environmental journalists.