rjw4law, you say to watch for when there is "repaving of streets". I think you meant strictly re-doing of sidewalks. Because when they grind out streets (ie.: pavement verses sidewalks), it's rarely ever any good. Only sidewalk demos are good, not street demo's. The reason is, that the asphalt is usually only ground out (to make depth/space for the new incoming asphalt) down to a depth of 3 to 5". They do not grind out down to the terra-firma level (with few exceptions). They re-pave on the existing base-rock DG compacted level only.
As opposed to sidewalks, which as you allude to, are typically laid right on top of the yester-year dirt or wooden sidewalk level, with no fill-layer involved (or very minimal fill, at best). This is because sidewalks only need be engineered to carry pedestrian weight/traffic, while streets carry car/truck heavy weight/traffic.