The Effects of River Contamination During Gravel Mining

Gravel mining disturbs the earth and may release toxic chemicals into the environment. Gravel mining has the potential to contaminate ground water and river water when it is close to the source. The effects of the contamination are evident in fish, wildlife, plant and human populations. Gravel mining is a controversial practice that is used to meet the human demand for resources.

Riparian Zones

• River contamination during gravel mining has a direct impact on aquatic plants and riparian zones along the river banks. The chemical pollution will contaminate the tougher plants and kill the sensitive plant species. Contaminated plants are also associated with the chemical spread to wildlife populations that rely on the plants as a food source. The death of the plants also reduces forage for insects and destroys habitat for wildlife. Gravel mining in a drainage where water is used for agriculture will directly affect human populations by adding chemicals to crops and livestock.

Fish and Insects

• Aquatic species are especially affected by mining contamination in rivers. Fish, insects and other aquatic invertebrates will absorb the chemicals and potentially die. Survivors of the chemical poisons are less likely to reproduce and genetic mutations may spread throughout any successful offspring. Gravel mining also alters the natural movement of sediment and spawning areas in associated rivers are often destroyed. The reduction of plant matter also affects the success of insect populations that fish rely on as a food source. Dams associated with gravel mines also contribute to blocking fish migrations and raising the overall water temperature in the ecosystem.

Ground Water

• River water cycles into underground aquifers that are used by human populations as drinking and household water. Shallow aquifers with a constant cycle of river water will not settle the contaminants to the bottom. Households with wells are affected if the water is not properly treated. The well may test as a clean water source before heavy mining in the region, but it is not immune from contamination as the level of mining and contaminants increase. Contaminated public water sources will respond by increasing the level of fluoride in water system.

Channel Destruction

• Gravel mining leads to channel destruction in rivers. The increased sediment changes the natural course of the river. The contaminants also kill vegetation that is essential for bank stabilization. The de-stabilized banks and extra sediment are ineffective for holding heavy flows between the banks. The chances of heavy flooding drastically increase and the extended flood plain risks property damage outside of the normal river course.