You’ve probably seen “disposal wells” in big, bold print in just about every Oklahoma publication over the last few years. And by now, you’ve probably read enough to know that Oklahoma is home to nearly 4,000 disposal wells. But do you know why we need them?

Disposal wells are necessary for the oil and natural gas industry to dispose of a thing called “produced water.” Most people don’t know it, but here in Oklahoma the earth actually produces more water than it does oil. Thus the term “produced water.” In fact, in some parts of our state, 10 barrels of water are produced for every barrel of oil.

This “produced water” is basically ancient seawater that has been trapped in rock formations thousands of feet below the earth’s surface for millions of years. This water, because it is so old and so far below ground, is impossible to drink, or use for anything on the surface without proper filtering and treatment.

So, disposal wells are used to put the untreated water back into the areas where it was originally found. Disposal wells have been used in Oklahoma for nearly 60 years and are heavily regulated and monitored by the Oklahoma Corporation Commission.

There’s been a lot of confusion between this produced water and the water that is used during hydraulic fracturing, which is called “flowback” water. Mike Paque, the Executive Director of the Ground Water Protection Council, explains the difference in this quick video.