Rivers begin wherever water touches the earth. Because rivers do not have a point source, they may become polluted anywhere throughout the hydrologic cycle from ocean to air to soil. The integrity of rivers begins with the integrity of the earth itself. Air and ocean and land pollution are not separate ecologic problems. They are but the parts of the same problem and the seam that joins them is rising, falling, moving water.
Rivers spring up from the oceans, fall from the sky, and seep through the earth.
Rivers are the threads that run through our world, and there is nothing that is not part of rivers.