Mist Underground Gas Storage

Meeting the demand for natural gas for our customers

NW Natural’s underground storage is located near Mist, Oregon, 60 miles northwest of Portland. In 1979, Oregon’s first commercial quantities of natural gas were discovered in that area. Since then, the storage field has been actively developed.

How is Mist Utilized?

By 2009, a total of 51 reservoirs had been discovered and 71 billion cubic feet (bcf) of natural gas, or about 667 million therms, had been extracted. This gas, called production gas, continues to flow in NW Natural’s system each day.

Once natural gas was extracted from two of the larger reservoirs, the Flora and Bruer Pools, NW Natural found that it could use them as underground storehouses. Large amounts of natural gas could be injected into these empty reservoirs—which are located in a large body of buried sandstone—and could then be withdrawn as needed.

Benefits of Mist

Underground storage at Mist and associated pipelines are the least costly way to meet the growing demand for natural gas in Oregon. The ability to store natural gas allows the company:

  • To reduce the amount of expensive pipeline capacity it buys during the heating season, keeping down consumer cost.
  • More flexibility in long-term planning for gas supplies.
  • Less reliance on the volatile spot market for gas purchases.
  • A tool for balancing supplies with demand on a real-time basis.
  • Diversification of its supply portfolio.