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Human Impacts

Point Source Pollution

Single source that discharges pollutants into the environment.

  • Smokestacks
  • Drainpipes
  • Chimneys
  • Effluent pipes from industry or wastewater treatment facilities
  • Generally easy to identify and control (cost not considered)

Non-Point Source Pollution

Discharge of pollutants into the environment over a large area from a dispersed source.

  • Fertilizer applications
  • Pesticide applications
  • Manure from domestic livestock
  • Automobile exhaust
  • Air pollution from metropolitan and industrial areas
  • Sediment from land use practices (grazing, urban development, agriculture, forestry)

Air pollution from urban or industrial areas:

  • Acid deposition
  • Nutrients (NOx) fertilization of oligotrophic ecosystems


  • Nutrients (N & P)
  • Pesticides
  • Toxic pollutants
  • Generally more difficult to identify sources and consequently control
  • May have origin outside the boundary of watershed of concern

Impervious Surfaces

Coming Soon

Land Uses and Natural Events

Land Uses Char