EARTH MOVING CAN BE DANGEROUS TO OUR HEALTH

As the most ideal locations for human activities are occupied, population pressures necessitate the use of more marginal landscapes. We commonly try to modify these landscapes to better serve our purposes. In so doing, we move tremendous amounts of earth.

Much of this earth moving is relatively benign, but some is hazardous to our well being, and some of the hazards may not materialize until long after the earth has been moved. Two objectives of this symposium are to make people aware of potential effects of their activities on future generations, and to encourage planners to consider long term consequences of their actions.

Road building, an activity that is responsible for a substantial fraction of human earth moving, is a good example of both the hazard and the mitigation achieved by careful planning. Good roads allow travel at higher speeds and thus increase the potential for serious accidents, and indeed traffic deaths are increasing. Furthermore, paving increases runoff, thus wasting water, damaging wetlands, and exacerbating flooding. On the positive side, however, modern engineering has substantially increased the safety of our highways.

We have been less successful in mitigating hazards resulting from earth moving in attempts to control nature. Jetties constructed decades ago to make a harbor are still resulting in losses of homes due to shoreline erosion. Levees designed to prevent flooding have exacerbated flood damage. Leaching of toxic chemicals from 19th century mine tailings are polluting waterways today. Dams built a century ago deprive us and our children of the spiritual enrichment that could be derived from the splendid landscapes the waters now cover. Even more worrisome is the rate at which earth turned by the plow is being lost from agricultural lands, reducing our ability to feed the expanding world population.

While many hazards resulting from our earth moving could be mitigated by careful planning and engineering, it is clear that a key element is population pressures that encourage use of land subject to disaster. Given the added benefits of a higher and sustainable standard of living for all, a long term goal of stabilizing Earth’s human population at ½ to 1/3; of the present 6 billion should be part of any plan to reduce our vulnerability to hazards resulting from our earth moving activities.