1. The Intersection of Cadastral Surveys and Floodplain Maps in GIS Daniel Dean Yates Undergraduate Department of Civil Engineering The University of Texas at Austin

2. The Cadastral Map Cadastral – adj., showing or recording property boundaries, subdivision lines, buildings, and related details. Commonly used for tax purposes Often referred to as plat maps Source: The Cadastral Map in the Service of The State, Kain and Baigent, 1992

3. The Yates Parcel Plat map with delineated property parcels “A plot rightly drawn by true information, describeth so the lively image of a mannor, and every branch and member of the same, as the lord sitting in his chayre, may see what he hath, and where he lyeth, and in whole use and occupation of every particular is upon suddaine view.” Surveyor’s Dialogue by John Norden, 1607 Source: The Cadastral Map in the Service of The State, Kain and Baigent, 1992

4. Travis County Parcels Close up of Travis County Parcels and Structures Source: Lower Colorado River Authority

5. Travis County Parcels and The LCRA 100 Year Floodplain

6. Fun with Databases

7. Joining the tax appraisal roll database with the parcels

8. Organizing the Data Separating the parcels by city

9. Taking a closer look at Lago Vista Selecting by attribute and exporting data as a shapefile

10. Taking a closer look…

11. Spatial Join

12. Improvement Values by City 3176 structures intersecting the 100 yr Floodplain

13. Del Valle Neighborhood

15. Thanks Lower Colorado River Authority –Wes Birdwell, John McLeod, Sunny Simpkins The University of Texas at Austin –Dr. David Maidment

16. Questions ? Boathouse going over Austin Dam, 1935 Flood