I have a city that I would like to divide up by its streets with the end result being polygons that are the blocks divided by its streets. In the original data that I have, the city boundary should be the outside boundary. It is a polygon. The city should be divided up by its streets. I have those in two files, I could use either - one is the road right of way which leaves space for the streets, the other is the road centerlines. Those are polylines.
Again, what I would like to do is subdivide the city into blocks. I have tried Union and then polygonize, which yielded an error message. When I checked the geometry the entire boundary came up invalid. When I try to convert lines to polygons, almost the entire city disappears leaving only a couple of blocks.
It's become rather circular at this point. I try one way, run into some problems, and someone tells me to try the other. I try the other way, someone tells me to try the first way. and on and on.
And here is a conceptual image (not from GIS, only for illustration). In the concept image, the thick blue line would be the polygon corporate boundary and the thin orange lines the road centerlines/rights of way.
What I would like to do is to merge the geometries so that each subdivided segment is its own polygon. In other words, in the end there would be five polygons from the conceptual image.
How can I do this?
Just to be clear I want the result to be polygons not polylines.