Revision of hydrographic layer of CRIM Basemap. This layer was constructed based on Digital Elevation Models, and the most recent imagery (IKONOS, 2001-02) and aerial photography available (USDA, 2004).
Completion of hydrograhic layers from CRIM basemap. From a sample of five quadrangles, it was estimated that original CRIM hydro data lacked about 45 to 60 percent of linear waterbodies. This layer is of extreme importance for Emergency Management and Mitigation, Resource Management and Watershed Management and Planning Programs among many other purposes.
ground condition
None
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Numeric coding information comes from CRIM basemap project which was performed by mapping contractors. Several classification and coding errors were found and corrected when doing the QA over all map tiles. Intermittent waterbodies and hydrographic names were taken from USGS Quadrangles (1948 to 1982).
All data layers were revised twice for logical consistency. Visual tests were conducted over all tiles using symbologic representation for visual recognition and differentiation.
Fortunately all Puerto Rico and nearby islands were completely covered. Data on linear or areal features were removed in cases of: housing developments, road developments using 2004 USDA orthophotos. Original data needed revision and completion due to tree canopy coverage. Updates were performed over areas recently developed (October 2004) using USDA & CoE Color Orthophotography. Waterbodies were interrupted at roads and bridges sides, following the original basemap procedure.
Positional Accuracy report is currently needed.
Centro de Recaudación de Ingresos Municipales (CRIM) provided original hydrographic data that needed to be completed.
Puerto Rico Office of Management and Budget performed linework completion and the integration of related attribute information using USGS Quadrangle data as a guide.
For this completion we needed to use the following data sources: Digital Elevation Models Orthoimagery and Orthophotos Software for surficial water network modelling.
The first evaluation of CRIM Basemap Original Data reflected that almost 50 to 60 percent of linear waterbodies were missing. We used available DEMs taken from CRIM basemap (10 meter resolution cells) to come up with flow accumulation maps. DEMs were devised using very detailed available topographic sources from CRIM data: mass points and breaklines (scale 1:2,000). Flow accumulation maps derived from that detailed topographic data were used as the first information source for stream location for future digitizing over more than 70 map tiles. These tiles correspond to the area covered by a USGS 7.5 min quadrangle.
Strems and waterbodies were digitized using Flow Accumulation maps (ArcInfo GRID). FA maps were symbolized to match a network similar very dense original CRIM hydro data found at some small places over Rincón and Humacao Quadrangles. We used a standard deviation representation method for FA GRIDs (0.25 std devs). The purpose was to cover the linear features present on USGS Quads and present a more detailed surficial water network layer. In addition and where available, topographic breaklines were used as a guide for stream digitalization using specifying snapping to these features and road bridges. We used IKONOS imagery for the first run (digitizing) to compensate for areas in which FA GRIDs were not reliable: flat areas near coasts or housing developed areas. The second run involved the determination of intermittent waterbodies and their names as present over USGS Quadrangles. Alternatively, we found some unnamed linear waterbodies that had names on TIGER line files. They were used only when USGS data was not present. When USDA orthos were available (2005) we used them to check other developed areas. At the same time we performed topological checking of these data. Topological corrections involved breaking lines when two or more lines met, checking for multiple overlaid lines and removal of unnecesary nodes. Some small islands (and Mona, Desecheo, Caja de Muertos islands) that were not present on CRIM basemap data were added using IKONOS imagery. The Eastern part of Vieques was also added using IKONOS because CRIM data does not cover that area. This work was done at an approximate scale of 1:5,000.
Dataset copied.
Internal feature number.
ESRI
Feature geometry.
ESRI
CRIM Basemap Original CAD Numeric Feature Coding
CRIM
CRIM Basemap Original Numeric CAD Feature Coding
CRIM
Feature description
PR OMB, Based on CRIM CAD Feature Codes
Determine if the linear waterbody is intermittent or perennial
USGS
Feature Name
USGS Geographic Names as laid over Quadrangles
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These data were prepared by an agency of the Commonwealth of Puerto Rico Government. Neither the Commonwealth Government nor any agency thereof, nor any of their employees, make any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the Commonwealth Government or any agency thereof. Any views and opinions of authors expressed herein do not necessarily state or reflect those of the Commonwealth Government or any agency thereof. Although all data have been used by PR OMB, no warranty, expressed or implied, is made by PR OMB as to the accuracy of the data and/or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by PR OMB in the use of these data or related materials.
Contact: isantiago@ogp.gobierno.pr
Contact Distributor
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