Greylock Midstream was formed in 2017 by ArcLight Capital Partners, who initially acquired the gathering and transmission assets of First ECA Midstream.  Our continued growth is supported by healthy cash flows and an enduring financial equity commitment from ArcLight.


Our customers experience:

  • a creative, professional engineering and construction team that guides them through challenges

  • our unique commercial flexibility and imagination

  • projects that are completed on time

  • incredible value with our best-in-class construction management practices