Now, there is another route, along a major roadway, with a higher speed limit and more lanes. But its not a direct route and is 0.8 miles longer. I doubt that the quality of life of this new community would be severely impacted if they were "encouraged" to take this existing route.
Anyway, take a video of people barreling down the hill and send it to a city council member. Newspapers also like this sort of thing when it's egregious enough.
When should it be resolved?
It's definitely the case that most drivers gain a bit of speed going down a hill, but it's been that way forever and it's not something you're going to change. So if one of your main concerns is the speed of traffic outside, don't buy a house at the bottom of a freaking hill.