Digging up metropolitan streets involves heavy political lifting.
Some web sites:
City Net,
CableRunner North America,
Metromedia Fiber Network
More technical & nuts and bolts info here.
This emphasizes the disadvantages of retrofitting.
At the very end of the 20th century many companies had the business plan of putting glass fiber into any trench that they could find. In particular owners of rights of way for railroads and pipelines put down fiber any time that had to dig a ditch along their right of way. Most of the fiber was dark in the sense that there were no specific plans then to use it when it was laid. Most of it remains dark. About 120 years ago there was a glut of railroad lines, most of which became useful before they rusted, but not without ruining many original investors. I think most of the activity of putting fiber in any ditch is one of the casualties of the .com debacle.
Today, in early 2002, Los Trancos Woods is planning to lay sewers. It is probably impossible to find someone who will lay fiber, or even conduits for fiber on pure speculation. The community might, however, or the ILEC might. (ILEC = “Incumbent Local Exchange Carrier” = SBC = PacBell) There are several approaches I can think of.
One big question in my mind is whether it is strategic to lay conduit just between man holes or also to houses as ditches are dug for the “last 100 feet” of the sewers. Would such local conduits lead to a man-hole? Does anyone know how this works in Palo Alto where there is some municipal fiber to the home?