Environmental consciousness is one of the great developments of the last decades of the 1900s.
Before the 1960s, pollution was like that famous quip about the weather: Everybody complained, but nobody did anything about it. That began to change slowly in the 1960s.
Thirty years later, visible pollution is much less severe in the United States and other wealthy countries, though concerns about global warming and loss of biodiversity remain.
Most voters are concerned about environmental matters, and politicians of both parties pay at least lip service to their concerns. But even a genuine interest in protecting the environment does not always make correct policy choices simple to discern. Ongoing controversies illustrate that fact.
Take the environmental costs and benefits of genetically modified organisms. The most widely grown are varieties of soybeans that have been genetically altered to make them tolerant of a specific chemical weedkiller. When a farmer plants such soybeans, he can avoid using traditional herbicides.
Instead, the herbicide, which the soybeans are tolerant of, can be sprayed over the entire field after soybeans and weeds both have sprouted and emerged from the soil. The herbicide kills the weeds but leaves the genetically modified soybeans alone.
Many environmentalists oppose growing such plants, claiming the possibilities of yet-to-be-determined effects on humans or animals that eat the crops.
There are also concerns that the genes could spread to other plants, eventually producing “superweeds” that are impossible to kill or making other plants toxic to human or animal life.
These are important concerns that should not be dismissed lightly.
But environmentalists should acknowledge the potential for the environmental benefit from the use of contact herbicides.
Not being incorporated into the soil, contact herbicides are exposed to sun and atmosphere and generally break down more quickly with fewer residues in soil or water. Moreover, genetic modification promises the development of plants that will thrive with less use of insecticides and synthetic fertilizers. Fighting their introduction does not mean preserving pristine, organic food production, but rather the continued use of higher levels of crude chemicals.
The best alternative for the environment is not clear. Two people can have equally acute ecological concerns and reach different conclusions as to whether we should press ahead with genetically modified crops or put every obstacle in their path.
To build or not build improvements to barge facilities on the Mississippi River constitute a second example of a policy choice where the trade-offs are complex.
The Mississippi River was long navigable as far north as St. Paul using shallow-draft steamboats. But it took construction of a set of 26 locks and dams from Alton, Ill., to Hastings to develop a 9-foot channel for use by modern barges. Most of those facilities were built in the 1930s, and many need repair or partial replacement.
The existing locks and dams certainly have damaged some plant and animal life. Changing the Upper Mississippi from a fluvial ecosystem that had annual floods and periods of low water to one in which a uniform depth was maintained year around, made it impossible for some plants and animals to survive where they had thrived before.
Periodic dredging to maintain a 9-foot channel also means that backwaters and other areas are filled with dredged materials. Many environmental groups oppose spending government funds on lock and dam overhauls. They fear such a program may be a Trojan horse for changes that would involve an even deeper channel, 10 or 12 feet instead of 9, which would in turn require even more annual dredging and spoil dumping, as well as more numerous and larger barge tows.
But shipping bulk products by barge is generally friendlier to the environment than trucks or trains. Fuel burned by towboats pushing barges is substantially less than that needed by locomotives pulling an equal amount of cargo. If the river were not used for barge traffic, substantial increases would be needed in highway and railroad construction, which also damages ecosystems and wildlife habitat.
There is great opposition by urban residents across Minnesota and South Dakota to proposed increased traffic on the DM&E railroad.
But the proposed traffic on that line would pale in comparison to that needed if rail transport were to supplant barge use of the Upper Mississippi. Again, the best choice for the environment is not inherently clear.
Economic analysis can point to a best policy when all the costs and benefits of all alternatives are known and quantifiable. That is seldom true in the real world.
In the end, citizens and their elected representatives must reach decisions based on information that is actually available and their gut estimates of the possible importance of unknown factors. Inevitably, not all will reach the same conclusion.
© 2000 Edward Lotterman
Chanarambie Consulting, Inc.