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I'm performing OSM clean-up work in and around Morgan Hill, California. I'm finding many problems that appear to be the fault of inaccurate data imported from TIGER — misspelled names, imaginary names where none exist, and imaginary streets where none exist. Since the TIGER import there has been considerable residential construction in my area and I'm adding street data wherever feasible, even without the benefit of GPS coordinates or satellite imagery, on the theory that it is better to have something in the database, even if it is not entirely correct, than nothing at all. Much of my work consists of aerial tracing and alignment. I also am improving the database by adding address data, points of interest, and so on.