Water is life. That may be a cliche, but it is also a fundamental truth. Without water nothing can live, and certainly not human beings. We depend on it directly to keep our bodies functioning but we also depend on it in indirect ways: To water our crops and to provide rivers in which goods may be shipped. And -- and this is no small thing itself -- because they provide beauty to our lives. However, despite the fact that water is vital, we (as humans) are all too often disinclined to care for it.
All environmental preservation must include an aspect of protection for watersheds. Indeed, protection of watersheds must often be at the center of a sound environmental policy. This paper examines the state of two Italian watersheds and what their future may be. That future, of course, will be determined in large measure by how the humans charged with the care of our blue planet carry out their stewardship.
Before looking at the specifics of two watersheds in Italy it will be useful to provide a general definition of what a watershed comprises. The United States Environmental Protection Agency defines a watershed in the following precise and neutral way: "A watershed is the area of land where all of the water that is under it or drains off of it goes into the same place" (United State Environmental Protection Agency, 2012).
However, a more poetic -- and because more poetic more accurate -- definition of a watershed is the explorer John Wesley Powell's definition of a watershed: "that area of land, a bounded hydrologic system, within which all living things are inextricably linked by their common water course and where, as humans settled, simple logic demanded that they become part of a community." A watershed is one of the most fundamental and important ways in which a community is defined. Indeed, a watershed often connects a series of communities over time: The watersheds that are centered on the two Italian lakes discussed here have been at the nexus of human settlements for millennia, for the geography of the lakes have again and again attracted people to live along their shores.
Given the importance of watersheds, the fact that they are imperiled in both the present and the future must be of dire concern. This paper examines the potential fate of two of Italy's watersheds. The first of these is the watershed that centers on Lake Como, long considered one of the most beautiful sites in Italy but now under attack from a number of fronts.
The lake's water is often bright green, a shade that is inherently lovely but that in fact indicates that the water is very far from healthy. Bright green lake water indicates a flowering of algae. While creating a lovely color, these algae rob the lake water of oxygen and so starves all of the other native organisms that would normally call the lake home. Not all life is equally a sign of a healthy lake. Such algal blooms are common in lakes throughout the world and are especially common where agricultural run-off pours phosphates into the lake's water supply.
Like every lake, Lake Como is affected by its shape as well as its underlying lithography. Lake Como is shaped more or less like the letter "Y" with small to moderate sized towns at various points along its shores. The lakebed exists thanks to glacial activity and the lake is currently fed by the Adda River. Because of the way in which Lake Como is structured in its southwestern end, the rivers that flow into the lake can back up and cause flooding.
While flooding can be inconvenient (and even, of course, dangerous) for humans, when it is a natural part of a lake's hydrological cycle any steps taken to reduce or entirely eliminate floods will prove to be detrimental to the lake's ecology. Despite the fact that this fact is well-known, humans continue to alter the course of rivers and the shape of lakes.
This is one of the problems that this watershed will face in the future: As the region becomes more heavily populated there will be more and more pressure to alter the shape of the lake and its sources to reduce the possibility of flooding.
Reducing the amount of water that flows into a lake is a sure way to decrease the water quality. With less water circulating, the basic biochemistry of the lake will be altered, which is likely to be to the detriment of many species. Some species may benefit, but if they do (and if they are native species) their success will come at the cost of the lake's complex biotic balance.
The above map provides an overview of the lake's shape and human habitation along its shores. The lake's long shoreline has been a boon for real estate over the millennia but it also makes the lake singularly fragile: Destructive human activity has a very long periphery to damage the lake.
The lakefront beaches of Lake Como bear signs telling people not to swim in them, although this is a caution that is often ignored (Popham, 2007). The reason for the warning signs is the high level of bacteria and other micro-organisms in the lake. Laglio, one of the lakefront beaches on Lake Como, has a truly horrifying level of bacteria:
Bacteria is measured in terms of "colony-forming units"(cfu), a measure of viable bacterial numbers per 100 millilitres of water. The upper permitted limit of cfu for lake water that is safe to bathe in is 100. But at Laglio the figure is 6,800-68 times too high. (Popham, 2007)
While the current state of Lake Como's watershed is already bad, its future is likely to be far worse as it will be affected by a range of factors, each one of which would individually be enough to do significant damage to the lake.
The fact that each of these factors could be deadly on its own does not have simply an additive factor but rather a multiplicative one. In other words, when these factors co-occur the combined effect can be many, many times worse than might be expected if one simply added the force of all of these factors together. For Lake Como, the most significant perils to the future health of te watershed are: "ever-more intensive agriculture that produces toxic run-offs, illegal housing and industrial developments that discharge effluent into the lakes, global warming which means there is less rainfall to replenish them" (Popham, 2007). And, exacerbating all of these other factors is the fact that more and more people will make more and more demands on the lake's water each year.
The challenges that face Lake Lugano are similar to those that face Lake Como. The following map of Lake Lugano show that it has the same basic shape as Lake Como, a fact that should not be a surprise given the fact that the entire country has been shaped by the same basic geological forces. Lake Lugano, however, is important in one highly significant way: It was created through human intervention. The lake, which crosses the Italian-Swiss international boundary, was created when the Melide dam was constructed between the towns of Melide and Bissone. The dam is anchored on a moraine, one of hundreds in the area of the area that bear evidence to the area glacial past. The lake is, therefore, both new and settled over an ancient foundation.
Lake Lugano is one of the most polluted lake in Italy and is unlikely to see any significant improvement in the near future, although it has improved to some extent since the 1960s (Belfast Telegraph, 2007).