After crude oil is refined into gasoline, propane, and other petroleum products, the products must be transported to consumers. Over 2/3 of crude oil and its refined products, such as gasoline, are transported through the more than 200,000 miles of petroleum pipelines in the U.S. Pipelines are the typical mode of choice due to their high levels of safety and cost effectiveness. Gasoline and other products are sent through shared pipelines in “batches.” Since these batches are not physically separated in the pipeline, some mixing or “commingling” of products occurs. This is why the quality of the gasoline and other products must be tested as they enter and leave the pipeline to make sure they meet appropriate specifications. Whenever the product fails to meet local, State, or Federal product specifications, it must be removed and trucked back to a refinery for further processing.
As the vast majority of Michigan’s petroleum products come from outside the state, Michigan receives a large amount of its petroleum products via pipeline. Two major crude oil pipelines from western Canada, part of the Enbridge (Lakehead) Pipeline System, enter Michigan from the northwest and southwest and supply both Michigan and eastern Canada. Several petroleum product pipeline systems supply Michigan, including the Wolverine Pipeline system, which runs from Chicago area refineries to the Detroit metropolitan area.
In addition to pipelines, Michigan imports large quantities of crude oil and other petroleum products through tankers on the Great Lakes. Detroit, Port Huron, and Sault St. Marie are Michigan’s main oil seaports. Michigan also receives crude oil imports from the Gulf Coast
Propane naturally occurs as a gas at atmospheric pressure but can be liquefied if subjected to moderately increased pressure. Because propane is 270 times more compact as a liquid than as a gas, it is transported and stored in its liquid state. Propane returns to a gas when released from its pressurized container where it is utilized for space heating and a wide variety of other purposes. Simply stated, propane is always a liquid until it is used. Although propane is non-toxic and odorless, an identifying odor is added so the gas can be readily detected
The primary mode of transporting propane within the United States is by approximately 70,000 miles of interstate pipelines. The pipeline system is most developed along the corridors between production areas and petrochemical consumers along the Gulf Coast and the agricultural-industrial consumers in the Midwest. The Northeast and South Atlantic States each are served by a single pipeline. The upper Midwest also is served by two lines from Canada. Other modes of transport include about 22,000 rail tank cars, 6,000 highway bulk transports, 18,000 local delivery trucks, about 60 inland waterway barges and several ocean-going tankers.