Historical Plat Maps of Dane County Digitized and Converted to GIS (1962-2005)

We constructed a time-series spatial dataset of parcel boundaries for the period
1962-2005, in roughly 4-year intervals, by digitizing historical plat maps for Dane County
and combining them with the 2005 GIS digital parcel dataset. The resulting datasets enable
the consistent tracking of subdivision and development for all parcels over a given time
frame. The process involved 1) dissolving and merging the 2005 digital Dane County parcel
dataset based on contiguity and name, 2) further merging 2005 parcels based on the hard copy
2005 Plat book, and then 3) the reverse chronological merging of parcels to reconstruct
previous years, at 4-year intervals, based on historical plat books. Additional land use
information such as 1) whether a structure was actually constructed (using the companion
digitized aerial photo dataset), 2) cover crop, and 3) permeable surface area, can be added
to these datasets at a later date.