Causes of Oil Pollution
Down the Drain: 363 Million Gallons
Oil is used regularly in daily life, for example in household machines such as lawnmowers and in the daily running of cars. Traditional industry, transportation, and spills from fuel depots and underground petrol tanks are the main culprits. Waste from our usage can end up in our water system, which eventually flushes out into the sea. The effect is actually much greater than a major oil spill, but is less publicised because it is a regular flow building up over time rather than a huge visible slick. Over the course of a year, just the oil left on the roads (based on a city of 5million people) that find its way into the drainage system is equal to one large tanker spill.
Routine Maintenance: 137 Million Gallons
Every year, bilge cleaning and other ship operations release millions of gallons of oil into navigable waters, in thousands of discharges of just a few gallons each. Bilge is a mixture of waste oil and water that ships should dispose of correctly. There is usually a cost for this disposal, for example in Canada it is about $6,000. Instead it is often released into the sea, despite this being illegal, punishable by quite large fines. Release of bilge oil is difficult to track so this figure can only be estimated.
Up in Smoke: 92 Million Gallons
Cars and industry create pollution in the air. This forms into particles that can wash into the ocean from the rain.
Natural Seeps: 62 Million Gallons
Release of oil is also a natural process. Oil is released through rock erosion and also seeps up from the ocean floor.
Offshore Drilling: 15 Million Gallons
The day to day process of offshore oil production causes oil pollution through general discharges and accidental spills. The North Sea is becoming increasingly polluted by spills from drilling.
Big Spills: 37 Million Gallons
Only quite a small amount of oil pollution is through spills or disasters (approximately 5%). This does not mean that the spills are any less serious as most of the other causes are gradual but oils spills are a huge almost immediate impact on the environment. Damage to wildlife and coastline can stretch for miles and miles. This damage is controllable.
One of the areas that we can control oil pollution is to stop the spills. Spills occur in a number of ways, usually accidentally whilst being transported. Spills can be caused by
Statistics analyzing the spill size and causes of the spills, demonstrate that most spills (92%) are under 7 tonnes and are generally related to routine operations for example when loading or unloading. The remaining 8% of oil spills mostly relate to accidents whereby a large quantity of oil is dumped into the ocean. 20% of these accidental spills involve quantities of oil in excess of 700 tonnes, a huge quantity of oil to pollute the sea.