NEW ORLEANS (AP) — The man who oversees the National Flood Insurance Program is visiting Louisiana for a tour of the state’s flood protection infrastructure as members of the congressional delegation fight the possibility of skyrocketing flood insurance premiums.

At issue as David Miller visits Thursday are flood insurance bills for homeowners who have historically been “grandfathered” at lower rates since they followed the rules in place at the time they bought or built their home.

Under a bipartisan overhaul of the flood insurance program last year, many of these homeowners face higher premiums when new flood maps are issued.

Democratic Sen. Mary Landrieu and a likely challenger in her re-election bid next year, Republican Rep. Bill Cassidy of Baton Rouge, both are set to attend a Thursday evening news conference with Miller.