This document discusses several types of water pollution. It begins by noting that as the human population grows, we are putting increasing pressure on water resources. This leads to poorer water quality and pollution of oceans, rivers and other bodies of water. It then discusses specific types of pollution, including arsenic pollution, and mentions the wide-ranging effects pollution can have on living organisms. The document also discusses surface water pollution, noting that surface water sources like reservoirs, rivers and lakes in the US are vulnerable to multiple sources of pollution including runoff from land.