Two Lower 48 midstream heavyweights are set to join forces in a $7.1 billion, all-equity merger between Energy Transfer LP and Crestwood Equity Partners LP.

The transaction, expected to close in the fourth quarter, would see Energy Transfer acquire Crestwood’s multi-basin natural gas, natural gas liquids (NGL) and crude oil infrastructure portfolio, and assume $3.3 billion of its debt.

“Over the last few years, Crestwood has been a staunch proponent of consolidation within the midstream space,” CEO Robert Phillips said Wednesday during a conference call to discuss the deal.

He highlighted that Energy Transfer’s network would connect Crestwood’s gathering and processing (G&P) systems in the Permian Delaware, Powder River and Williston basins with end users in the...