Private-equity investors think they have found a goldmine in wastewater management.

The Wall Street Journal writes, “Sensing an opportunity for an enormous return, private-equity corporations have invested greater than $500 million into wastewaterdisposal firms [such as] Solaris Water Midstream, WaterBridge Assets LLC, and Oilfield Water Logistics. There are roughly a dozen of those waterfocused firms that analysts mentioned might every be value lots of thousands and thousands of dollars.”

KKR & Co., the enormous private-equity corporation, is believed to be looking to get in on the action.

The Permian is expected to produce 5 million barrels of oil a day by 2023. Along with that comes a lot of briny water from the fracing opera tions. Analysts say the Delaware Basin has a water-to-oil ratio about 5 to 1. Handling wastewater can cost a driller up to 25 percent of operating costs. So, the question is how to deal with all that wastewater. Some companies are building pipelines. Others are going into production-water reuse. And that takes money for which the private-equity players are opening their wallets to finance.