HOUSTON (KTRK) -- Even as a large number of Southeast Texas roads and highways are closed Tuesday, Monday saw countless thoroughfares deep underwater. So many of the spots we travel in and around Southeast Texas were impassable. Among them was the Grand Parkway at FM 2920, a brand new road."The reality of it is we had an excessive rain event," said Texas Department of Transportation Raquelle Lewis. She said that the road performed as designed for a 100-year flood, not the 500-year event we experienced Monday."We don't have the resources or the capability to design to a level that would allow for a facility to stay dry under such an extreme rain event," Lewis said.Still, they are investigating the parkway's performancs as they will roads that have flooded before, such as Westpark. It flooded this week as it did 11 months ago in the record flooding then. Both times people died. TXDOT says it has installed flood gauges to warn drivers of water levels since last May.The county, which pre-stages resources ahead of a flood, says responding to an emergency is a two-way street, especially when it's under water."The public needs to listen to those messages," said Harris County Emergency Operations Spokesperson, "Stay off the roads when we tell them to stay off the roads."For its part the city has installed 19 high water flashing lights since last May. They plan another eight and will look at ways to improve now as it did then."We certainly will be in conversation with TXDOT," said Mayor Sylvester Turned during a press conference Tuesday afternoon. "There are a lot of lessons to be learned in any incident of this kind. I think we have to learn from it and I think additional things that we can do or should be doing we are going to do to."