M.4 Terrain Submittal Standards
Summary of questions/comments received for the Terrain section on DHS Interactive and responses provided through October 10, 2008.
| Topic | Comment | Response |
|---|---|---|
| Accepted File Formats | Will the terrain data type be supported with the ESRI geodatabase? If so, a submittal location in the folder structure should be added. | The terrain data type is acceptable. The next revision of the document will reflect this change. |
| Certification of Work | Certification of terrain data by an ASPRS Certified Photogrammetrist should be optional. Engineers or Surveyors for the Study Contractor should not have to seal this certification. The mapping contractor requiring the terrain data should be responsible for certification. | Agreed. The revised document now states, "This form must be signed by a registered or certified professional from the firm contracted to perform the work, or by the responsible official of a government agency." |
| Directory Structure | Frequently supplemental data, such as as-built drawings of dams or GIS representations of culverts exist and are helpful. There is currently no location to add these data in the file structure. It appears that 2D and 3D breaklines will be required, as well as bathymetric files. These files are not previously described and may not be needed. |
A directory was added for as-built data to the revised version posted late September. The breaklines are not required unless they are a component of the terrain data utilized for the analysis. Either 2D or 3D breaklines must be submitted depending on the type created for terrain data used in the analysis. If both are available, both must be submitted. 2D breaklines can represent something like the edge of a tennis court and keep data from mixing with the elevation calculations. 3D breaklines have elevations associated with the line and are integral to elevation calculations. Submittal of bathymetric files are only required when those are used for a study, such as a coastal study or large riverine analysis. |
| Metadata | Metadata from data providers should be included in the data documentation, in addition to the FEMA Terrain Metadata Profile. | FEMA will look into adding that to the text in the next revision. |
Last Modified: Tuesday, 04-Nov-2008 15:01:24 EST