Why has it become a common practice for factories to pollute streams and rivers?

Answer 1

This question should have been "Since factories polluted water since their startup in the industrial revolutions, why have they now initiated massive pollution control programs?"Initially there was a tremendous problem with mills, blood boilers, smelters, rendering plants, abattoirs, knackers shows and others. This was caused by their locations (generally in the middle of residential areas and in cities), the lack of pollution control systems, and a disregard for the impact on receiving streams and groundwater. Air pollution was also evident from the smells related to the processes and the massive amount of sulphur dioxide released from the coal used for fuel.

Since that time zoning has regulated where the factories may operate, what waste disposal and water treatment must be in place and what mitigation for other emissions must be employed.

There e has also ben a development of a vocal public, based by scientific findings, to require the industrial sites to reduce pollution and the subsequent impact on people and the environment.