Mile markers on U.S. interstates are maintained by the federal government. President Franklin Roosevelt was the first to appoint a committee to focus on the nation's roadways.
The Federal-Aid Highway Act, as well as mandates that were later put into place by the federal government, initiated funding to maintain and build public roadways like the interstate system in the United States. Through this, there were requirements set forth in terms of how the roads should be cared for. Ensuring the signs on the roadways are maintained is set up through this act in order to keep the roads safe and at optimal conditions for drivers. The work is funded through sources like taxpayer money.