Who manages the system of changeable message signs in coordination with local governments?

The Texas Department of Transportation (TxDOT) is responsible for managing the system of changeable message signs throughout the state, which includes coordinating with local governments to ensure that these signs provide relevant and timely information to drivers. TxDOT's role encompasses the planning, implementation, and maintenance of these signs, focusing on traffic safety and effective communication of road conditions, traffic disruptions, and event information. The collaboration with local governments is essential because it allows for updates that align with local traffic events, improving the overall traffic management strategy in the area.

This coordination ensures that the messaging on these signs is not only relevant but also enhances public safety, helping to facilitate smooth traffic flow and assist drivers in navigating roadways efficiently. Other organizations mentioned in the other choices may have roles in broader transportation regulation or local governance but do not directly manage these specific systems of signs in coordination with local authorities.