SPATIAL DATA LINEAGE REPORT ------------------------------------------------------------------- LAYER NAME: Topography 1-foot (polygons and lines) DISK LOCATION: /disk5/elev01/ FEATURE TYPE: Line/Poly MAP UNIT: SPARSE SOURCE SCALE: 200 PROJECTION: UTM Zone 17 meter HPGN GRS80 DESCRIPTION: Topography 1foot (contour) LAST UPDATE: 05/23/00 SOURCE: This data layer was digitized from the District's set of one foot contour mylar maps. These mylar maps were developed from stereo models based on aerial photographs. All of the approximately 1100 maps were digitized under contract #92W289. For more information, see the SJRWMD Water Resources Department, Division of Engineering, contact: Kristina Hickey. DISTRICT COVERAGE STATUS: Sparse, see graphic NOTES: Data development - All contours and spot elevations were plotted on mylars with an aerial photograph backdrop. Horizontal control, bench marks, and vertical control were plotted as points on the mylars. The contours and points from the mylars were hand digitized. The data was then trans- formed into state plane coordinates using the horizontal control points. ACCESS TO DATA: An assembled one-foot contour layer for all the available sections is complete and GIS users can access the data in coverage, shapefile, and SDE formats all of which were reprojected to UTM Zone 17 HPGN compatible with all District data. This compilation and mapjoin was done inhouse and here is some brief info for data access and as processing procedures. For SDE access, follow the instructions in GISDOC to connect to SDE in ArcMap, ArcCatalog, and PC ArcView (note Unix Arcview connection to SDE is not available and it will NOT be available). The SDE layer names are as: topo_1ft_poly -- for polygon topology topo_1ft_line -- for line topology Also, a coverage with both polygon and lines is located at: /gislib/covs/contours/sjr1ft/sjr1ft In addition, shapefiles are created based on the SDE layer and they are located at: /gislib/shapefiles/sjr1ft_poly /gislib/shapefiles/sjr1ft_line Please note that these shapefiles will be replaced regularly by the corresponding SDE layers. For this reason, changes to the shapefiles will be lost. The 1-foot contour layer is very large even though it covers a very small area. It is comparable to the entire 1995 land use/cover dataset. For this reason, one should attempt to use the SDE layer if possible. HOW COMBINED LAYER WAS CREATED: A. Scanned through /englib/covs/one_ft_topo/... directories and identified all those section-size coverages that satisfied the following conditions: 1. Contain polygon topology 2. Contain line topology 3. Coverage name did NOT contain utm There were 1008 sections that satisfied those conditions. B. For each of all those 1008 section-size coverages, the tolerance values were set to: Fuzzy 0.001 Verified Dangle 0.001 Verified Tic Match 0.001 Edit 0.001 Verified Node Snap 0.001 Verified Weed 0.001 Verified Grain 0.001 Verified Snap 0.001 Verified Database ID 0 Transaction ID 0 before a clean and/or build. C. The 1008 small coverages were mapjoined to four larger coverages due to the fact that there is a limit (max 400 coverages at a time) to mapjoin. In addition, an item EDGE was added all those sections that did not contain one, and this item was set to (-9) to distinguish it from 0 or 1. D. The larger coverages were each projected from the existing "SP" to the UTM Zone 17 HPGN system (/gislib/amls/projection_files/sp27- utmhpgn.prj), then reset all the tolerance values to minimum or zero before a clean and build. E. A final mapjoin was carried out from the larger and reprojected UTM coverages to create a master coverage sjr1ft. F. Then the lines and polygons in the UTM coverage were inserted into SDE as separate layers of lines and polygons. ------------------------------------------------------------------------------- PAT ITEM DEFINITIONS: COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME INDEXED? 1 AREA 8 18 F 5 - 9 PERIMETER 8 18 F 5 - 17 A192508T# 4 5 B - - 21 A192508T-ID 4 5 B - - 25 P_ELEV 3 3 I - - 28 P_TYPE 1 1 C - - UNIQUE PAT ITEM VALUES AND DEFINITIONS: ITEM VALUE DESCRIPTION ---- ----- ----------- P_ELEV <variable> Elevation in one foot increments P_TYPE Type: D Depression I Intermediary P Peak AAT ITEM DEFINITIONS: COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME INDEXED? 1 FNODE# 4 5 B - - 5 TNODE# 4 5 B - - 9 LPOLY# 4 5 B - - 13 RPOLY# 4 5 B - - 17 LENGTH 8 18 F 5 - 25 A192716T# 4 5 B - - 29 A192716T-ID 4 5 B - - 33 C_TYPE 1 1 I - - 34 C_DESC1 1 1 I - - 35 C_DESC2 1 1 I - - 36 C_ELEV 3 3 I - - 39 C_LOW 3 3 I - - UNIQUE AAT ITEM VALUES AND DEFINITIONS: ITEM VALUE DESCRIPTION ---- ----- ----------- C_TYPE Contour type: 0 ? 1 Normal 8 ? 9 ? C_DESC1 Contour Description 1 0 ? 1 Approximate 4 Best estimate 5 ? 9 ? C_DESC2 Contour Description 2 (may not always be used) 0 ? 2 ? 6 ? 9 ? C_ELEV Elevation in one foot increments: 0 Bounding box, closure arcs <variable> C_LOW Low elevation for carrying contours 0 Contact Engineering staff for further information. ------------------------------------------------------------------------------- ANNOTATION: None Level#: Notes: