There is a federal government manual that guides decisions for transportation engineers regarding roads. While it is notable that it is going to be revised for the first time in eleven years, there is also a process for public comment:

The Federal Highway Administration released a draft of proposed changes late last year. The last time the manual got an update, a few thousand people, mostly transportation professionals, submitted comments. This year, 26,000 comments poured in from all over the country.
Some arrived from big companies, including the ride-hail and mobility company Lyft, the Ford-owned scooter-share company Spin, and the Alphabet company Sidewalk Labs. Each asked for a major rewrite that would, as Sidewalk Labs put it, “more closely align with the equity, safety, and sustainability goals of American cities, as well as those of the Biden administration.”
Others came from individuals. “There’s a broader set of people who see that these streets don’t work, that there are too many people getting killed, that they’re too unpleasant. It’s not consistent with what a place or a community should be,” says Mike McGinn, a former mayor of Seattle and executive director of the group America Walks. He credits those everyday activists with the new interest in the design document—and his own group, which urged thousands of people to submit comments to the federal agency…
The last time the manual got an update, the process took more than a year; with the volume of comments this year, it may take longer. A spokesperson for the Federal Highway Administration says the agency “needs to carefully consider all comments before determining next steps and the timetable for updating the manual.” Given the interest, that might take a while.
One of the reasons Americans like local government is that it is easier to interact with the officials who are making the decisions. For example, in a small town to a moderately sized suburb, a resident who has feedback on a municipal decision can probably even convey this face-to-face or in a public meeting. As the size of the municipality grows, it becomes harder to meet with local officials.
At the federal level, some might feel that decisions are made by an abstract group of people in a place far away. This idea has been expressed regularly in recent years: Washington D.C. is out of touch with the rest of the country.
However, this process of public comment described above offers an opportunity for people around the United States to comment on federal guidelines for roads. In the age of the Internet and social media, this is even easier to do: people can hear about it through email or social media feeds and submit comments online.
How exactly the federal agencies in charge here work through all of these public comments would be interesting to examine. Assuming they are all read or analyzed, do they look for the most common themes? Or, are some comments weighted more than others? This sounds like an important qualitative research process in order to find the patterns in all of the comments, discuss, and then incorporate (or not) into a revised manual.