Point source pollution can be directly traced to a particular source, such as a sewage pipe leaking wastes into a body of water, or a factory discharging wastes in the same manner. Nitrogen is the by-product of human and animal waste (sewage).
Nitrogen makes up about 78 percent of our air. Humans and other organisms cannot use the nitrogen in the air known as free nitrogen, but we need nitrogen in order for us to carry out our bodily processes. We obtain this nitrogen through the foods we eat. How this nitrogen is converted to nitrogen we can use, known as fixed nitrogen, is by lightning that fixes free nitrogen, or by nitrogen fixing bacteria found on the plant roots of legumes such as clover and alfalfa. We eat the plants or the animals that eat the plants and obtain the nitrogen that way. When we die and decompose or produce waste, the nitrogen is returned to the soil by bacteria that decomposes dead and decaying organisms. When it precipitates, runoff from the land washes into rivers and streams and eventually makes it to the Sound. Fertilizers, either from natural sources such as manure, or manmade, in the case of synthetic fertilizers add to the increase of nitrogen to an environment. Fertilizers are used on farms and lawns. This type of pollution is nonpoint source of pollution. Efforts are being made to reduce the amount of nitrogen load to the Sound.
Oil spills have destroyed thousands of seabirds and millions of sea creatures. For our dependence on oil, our thirst for it has put our waterways in danger. The first disaster happened in 1967 when the tanker, the Torrey Canyon hit a reef and cracked open spilling oil on the shores of the British Isles. There have been many accidents since such as the Exxon Valdez which hit a reef in 1989 and spilled oil on one of the most productive and scenic coast along the Pacific Ocean. Of course the disaster of the oil rig that spewed gallon and gallons of oil into the Gulf of Mexico.