Under the agreement, DBP will have rights to use the BEP for up to 60 years.
The BEP runs about 23km from the North West Shelf gas plant through the environmentally and culturally sensitive Burrup Peninsula.
DBP said this approach allows it to defer any requirement to expand the capacity of the section of the DBNGP which runs through the Burrup.
The use of the BEP to supplement the capacity of the DBNGP is an important component of DBP's proposed Stage 5B Expansion Project, and reduces the total costs of the project, DBP added.
DBP is currently securing funding for Stage 5B of the pipeline, which will help meet the lease payments for BEP.
DBP executive chairman Stuart Hohnen said the term of the lease agreement will begin within 12 months, subject to the satisfaction of third-party approvals.
DBP is majority-owned by Duet Group, with Alcoa and Babcock and Brown Infrastructure as minority owners.