Federal regulators gave the official go-ahead Thursday to the joint venture to build the Southeast Supply Header natural gas supply pipeline.

Planned by Houston-based companies Spectra Energy Corp. and CenterPoint Energy Inc., the 36-inch pipeline will transport up to 1 billion cubic feet of natural gas per day from a CenterPoint-owned hub in northeast Louisiana to one co-owned by Spectra in Mobile. A segment will cross the Mississippi River into Warren County at LeTourneau and head southeast near the Yokena community.

It represents the final step in the Federal Energy Regulatory Commission’s process.

Once built, the companies envision the pipeline adding reliability to markets now served mainly from the Gulf of Mexico.

“We appreciate FERC’s comprehensive review and timely approval of this important infrastructure project,” said a statement of the companies. “SESH is committed to constructing, operating and maintaining this project safely and ensuring that impacts to landowners, communities and the environment are kept to a minimum.”

FERC’s approval also allowed for three mainline compressor stations and two booster compressor stations to be built along its path, including one near the beginning of its route across Warren County.

Its final route through Warren County will be determined by ongoing talks between the pipeline and property owners near the Loosa Yokena archaeological site. Initial maps have the pipeline running just north of the historic site and not within a zone deemed harmful by state archeologists. The landowners differ, saying the site has yet to be explored. Eminent domain litigation remains an option for the company. Environmental impact was termed substantive but not significant in a study completed by FERC in August. Final cost estimates grew to $840 million in the project’s final filings with FERC. Construction is expected to begin before year’s end and wrap up by summer 2008.