You almost have to be an expert to recognize it, but there was a significant event this week in the effort to bring high-speed rail transportation to Texas.The Federal Railroad Administration filed a “Notice of Intent to Prepare An Environmental Impact Statement” for a privately financed high-speed rail line between Houston and Dallas.What that does is start the process of gathering information and public input on the proposed project. The line itself is expected to be financed entirely by Texas Central High-Speed Railway, which has ties to the company that runs high-speed rail in Japan.Tarrant County has a stake in this proposal, and it’s not just the ability of local residents to drive to Dallas and take a 90-minute ride to Houston.A separate effort, spearheaded by Bill Meadows, a former member of the Fort Worth City Council and the Texas Transportation Commission, has been put together to study extending the Houston-Dallas high-speed line through Arlington to downtown Fort Worth.Meadows is upbeat about the federal notice filed Wednesday.“This is good news,” he told the Editorial Board on Thursday. “It’s a formal step forward.”Progress on the Dallas-Arlington-Fort Worth link will take longer. The good news there, Meadows said, is that a $15 million federal grant to enable the state to study high-speed rail will be devoted entirely to the Metroplex link.That’s more than enough to launch the necessary separate environmental study for the local link, Meadows said. That work is expected to be launched this fall, he said.It’s important for Tarrant County to keep pace with forward movement on high-speed rail. That will be difficult, because private financing for the Houston-Dallas route might help it move fast.The Fort Worth-Arlington-Dallas link will require public financing, which is a long way from being figured out.Still, an environmental study of the route from Houston to Dallas covers much more territory and potential for delays.The Metroplex link is expected to follow the Interstate 30 corridor, an environment that’s already mostly concrete.Solid planning will be crucial. Tarrant County could benefit greatly from this expansion of Lone Star State transportation.