I was hoping to concentrate on surveying rural roads in the Shire of York which are not currently in the database, since nearly all of the streets within the town have already been mapped. I checked the streets against a local town map to see what needed to be done within the urban area and noticed one street (Seabrook Street) was mapped south of Balladong Street and not north, where it actually is. Decided to GPS survey up and down these and nearby streets in order to make a correction.

Discovered that there's something quite amiss with the mapping of York's town streets. They are mostly all there but some distances are wrong, meaning some streets are too short and some too long. Some areas are accurate (Langford Crescent, Andrews Road and Camfield Place in the York Estates, for instance) and the section of Balladong Street I surveyed is fine. But the more I look at other areas, such as the CBD around Avon Terrace, the more inaccurate it is.

I also surveyed Pioneer Drive up to the Mt Brown Lookout and the junction with Herbert Road was way out.

Before uploading my GPS traces to OSM I open them in GPX format in Google Earth and they are perfect, matching up exactly with the Google Earth image and the Google streets, so I'm sure this isn't a problem with my surveying. My traces also match up with other ones going up Pioneer Drive.

Looks like I have no choice other than to survey all of the streets in York to see how widespread the errors are and make the corrections. I'll do a framework of main streets first to see what parts of town are OK and which bits are inaccurate, then fill in the problem areas. Existing rural roads outside the town seem fine.

I wonder where the current mapping came from? It doesn't have a "source" tab.