Thermal Pollution And Its Causes

By Author: Rushing RIvers Institute
Total Articles: 2
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When someone is asked to define the kinds of pollution they are aware of, rarely will one of their answers be heat. In reality heat, human-induced heat to be exact; is one of more common and lethal types of pollution by which our rivers are threatened.

Many of us never take the time to examine how our electricity reaches our houses and businesses. The very computer you're reading this article on is powered by an unseen, and unquestioned source of energy that you just assume will be there when you plug your device into the wall. In many locations, that energy is directly powered by nearby rivers donating their water to our devices such as dams and biomass structures to power turbines and generate electricity.

The tradeoff is not equal, however. A drastically lower percentage of the water which is removed for cooling or powering purposed is replaced, and the water which is put back can be lethal to the river's inhabitants. When the water is removed and, as in the case of the proposed Russell Biomass plant, is used to cool industrial equipment, its temperature drastically increases, and this heat is then ...
... carried back into the river. This is known as thermal pollution.

Coupled with this, removing the naturally occurring trees and other vegetation in the river's watershed area to make room for a power plant or dam, or to remove materials necessary for its perpetuation, also contributes to thermal pollution. As the shade and river cover decreases the direct amount of sunlight a river will catch increases, turning pools in the now much shallower river into perfect solar heat receptors, thus dramatically raising the temperature of the water.

Unfortunately, our rivers are already getting warmer due to global warming and decreased flows caused by increased human use. Adding intentional and easily avoidable thermal pollution to this already tenuous situation is simply irresponsible.

Fish, as well as other aquatic organisms, are highly sensitive to changes in water temperatures; their bodies have evolved to require certain characteristics of the surrounding environment to remain relatively stable. Not only are they accustomed to a specific habitat heat, but their source of oxygen can also become compromised. Higher levels of oxygen will exist in cooler water temperatures and as it warms, the available oxygen significantly drops for the dependant creatures.

Fish, after recognizing that the surrounding environment can no longer support their species, will migrate elsewhere if it is possible to do so, or they will simply die off. A sudden drop in biodiversity can shock the food web of an area and drastically lower its health.

Rivers, such as the massive Colorado River, have felt the effects of this pollution. Other less known rivers, such as the Westfield River in western Massachusetts, will potentially face these issues in the near future. On the Westfield River specifically, there is a potential biomass project under consideration. While the Russell Biomass Plant is intended to provide the area with greener energy, all of the consequences of its construction have not been fully explored.

As with the examples explained above, the biomass plant will be using the river to cool its equipment while only replenishing approximately 15 percent of the water which is taken. This is unfortunate and unnecessary as there are presently other technologies available that utilize air instead of water in industrial cooling processes which could easily prevent the removal and subsequent heating of the river water.

Additionally, Russell Biomass has proposed using wood-chips a primary source for fuel, which leads to further questions of the ability of Massachusetts to be able to sustainably provide the resources necessary to power the plant without endangering other, non-water resources.

The biomass plant is a noble endeavor; any advocate of nature can see its positive proposals. The devil, as they say, is in the details. Further investigation should be conducted in order to smooth over some of its rougher edges in order to make this proposal one that we can all get behind. In the case of the biomass on the Westfield River, opposing points of view have been silenced by its proponents in the form of refusing to hear legitimate, expert testimony from scientists in related fields. Collectively we must agree to hear all relevant facts and data in order to make an informed decision that will impact our lives in the very near future.

Yes, as environmentalists we support the development of cleaner and more efficient energy technologies, but we cannot sacrifice some of our resources to spare others. It is simply not a sustainable solution to cause a different kind of pollution while reducing another. Green energy production must be holistically created to provide the lowest impacts possible on our environment, or it will not be green at all.
Rushing Rivers Institute is an environmental non-profit organization dedicated to stopping river degradation. For ways to help, visit their website about river conservation.