M.5 Survey Submittal Standards
Summary of questions/comments received for the Survey section on DHS Interactive and responses provided through August 31, 2008.
| Topic | Section | Comment | Response |
|---|---|---|---|
| Photographs | M.5.2.1.3 | Many of the structures that are surveyed are obscured by underbrush and therefore makes it difficult to take one clear photograph of a structure's face. Multiple photos are necessary, so provide guidance as to the preferred method of naming these files. Would it be preferable to "stitch" these photos together? | Stitched photos are preferable in locations where a single photo would not allow clear depiction of an obscured structure, which would match the naming conventions. |
| Length of Cross Sections | M.5.2.1.3 | Required distances are not provided for extending surveyed cross sections beyond either the channel bank or end of the structure. | Surveyed cross sections must be extended a minimum of 15 feet beyond the channel bank or the end of a structure. |
| EOP (Edge of Pavement) Code | M.5.2.1.4 | Is the EOP code required or optional? Should an EOP shot be taken on the edge of an unpaved road or parking area if the edge is well defined? | The EOP code is optional. The shot is taken at the edge of the pavement or gravel road on the roadside of the transition. This is used to help in defining Manning's roughness coefficients for hydraulic modeling. |
| EOB (Edge of Bridge) Code | M.5.2.1.4 | Although shown in Figure M-4 "Typical Bridge Sketch," the EOB code is not listed in Table M-2 "Survey Codes." Does "EOB" also shift to the side along with RDCL on a superelevated road, or is it intended to remain on the centerline of the structure? | The EOB code should be added to Table M-2. The EOB should be surveyed at the high point in the road, rail, etc. However, interstates are surveyed in the emergency lane and railroads at the outside edge of the ties when centerlines cannot be safely surveyed. |
| Pipelines | M.5.2.1.4 | Neither the current Appendix N nor the proposed Appendix M provides codes or guidelines for surveying pipelines. | If surveying of a pipeline is needed, the existing codes for crown and invert, or for top of deck and low chord, could be used to define the structure. A sketch is critical to communicate the survey information to the engineer. |
| Culvert Codes | M.5.2.1.4 | Table M-2 "Survey Codes" does not list and describe all of the culvert codes shown on the subsequent photograph and sketch, such as CULINV, CUL, CULCL, USCR, and DSCR. | The CUL code needs to be added to Table M-2. The CUL code is used to define the shape of non-typical structures. |
| Arched Bridge Codes | M.5.2.1.4 | "Survey Codes" has been amended to reflect codes for arched culverts, but not for arched bridges. A code or other guidance for defining these openings is needed. | The LC (Low Chord) code can be used to define non-standard shapes such as an arch. By using multiple LC codes, the LC and the top of the arch and bottom of the arch can be defined. A sketch should be provided to describe the location and description of this code for various shots taken. |
| BM vs. ERM | M.5.2.1.4 | "Survey Codes" lists BM as Bench Mark and does not list the current code ERM as Elevation Reference Mark. In addition, some of the figures, as well as the dam and cross-section photos and the cross-section sketch do not reflect a BM/ERM. Does this mean it is no longer required to establish a BM/ERM at these locations? | “Survey Codes” will be revised to include “ERM.” ERMs must be set at any structure. While not visible in the dam example, one must still be set. ERMs at cross sections depend on the distance between them and/or the closest structure. If it is more than 0.5 miles to the nearest ERM location, then an ERM should be set at the cross section. |
| Dam Crests | M.5.2.1.4 | There is no clear statement regarding how we are to survey (or ignore) sluicegates, crest gates or flashboards. | The surveyor is responsible for collecting field data to define the limits of operation for the structure, and must also shoot the existing condition. Multiple weir codes may be used to collect data for the gates, flashboards, and other operable type structures with an explanation of the multiple shots noted in the sketch. |
Last Modified: Thursday, 04-Jun-2009 13:41:02 EDT