Veresen Midstream is a 50/50 limited partnership of Veresen and affiliates of Kohlberg Kravis Roberts & Co (KKR).
Under the terms of the agreement, Encana will sell its 500km pipeline and 675 million cubic feet per day of compression facilities.
Encana executive vice-president of midstream, marketing & fundamentals Renee Zemljak said: "We are unlocking value from our midstream infrastructure that we can redirect to strategic upstream opportunities while ensuring reliable, efficient midstream service to support our ongoing operations and development in the Montney."
Encana will receive about C$412m ($354m) from the sale and actual costs accrued in 2015.
Veresen Midstream will also undertake up to C$5bn of new midstream expansion to support development within the Montney.
Encana and CRP plans to invest between $600m to $700m in the play in 2015.
The transaction, which is subject to regulatory approval, is planned for completion in the first quarter of 2015.
