California High-Speed Rail Authority members will learn more this week about long-awaited environmental and engineering reports for high-speed trains in the San Joaquin Valley.

The authority's board meets Thursday in Bakersfield, where its staff will provide updates on complex environmental-impact reports for segments from Merced to Fresno and Fresno to Bakersfield.

The two Valley sections are planned to be the first pieces built in a proposed system of 220-mph trains linking Northern and Southern California.

The EIRs, being prepared by engineering consultants working for the authority, are required under both state and federal law for the massive transportation project. Draft versions of the reports likely will be issued this month for 45 days of public comment. Comments from residents, businesses, city and county officials and state and federal agencies will be evaluated by engineers; any changes that make their way into final reports will be considered late this year or in early 2012.

The draft reports are expected to offer the first formal recommendations for a preferred route for high-speed trains to zip through the Valley between Merced and Bakersfield.

North of Fresno, two potential routes have been in play -- one that generally runs along Highway 99 and the Union Pacific railroad tracks, and the other near the Burlington Northern Santa Fe freight rail tracks now shared by Amtrak passenger trains.

South of Fresno, the only major option generally follows the Burlington Northern tracks through Fresno, Kings and Kern counties, veering east from that line to avoid going through Hanford -- a route that has riled farming and dairy interests in Kings County.

Also on Thursday's agenda are: discussions of route sections from San Francisco to San Jose and San Jose to Merced; hiring consultants to handle right of way purchases; how to hire contractors for design and construction; and the search for a new public relations consultant.