CHSRA says it will be a "few months" more before construction begins, but no date has formally been set for the groundbreaking ceremony. Initial preparatory works, including surveying and soil testing, began last month.

CHSRA says it has the all the necessary permits and acquired land to begin construction on the 47km stretch between Fresno and Madera, but further land acquisition still needs to be completed, and the project faces two imminent lawsuits, one of which is due to start next week and the other in November.

"We could be out there this week if we wanted to just knock down one building," said CHSRA CEO Jeff Morales. "But that doesn't make economic sense."

Morales says CHSRA is still on target to spend $US 3bn in federal funds allocated to the project before the September 2017 deadline.