Thank you for the…

Thank you for the opportunity to comment on this draft Technical Bulletin. Our comments (Transportation and Engineering, Town of Oakville) are listed below. We agree that the content of this document provide recommendations and is not intended to be mandatory instructions to be applied in all circumstances. We are also very interested in the hydrologic and hydraulic modeling approach documents should they become available.

Comments:

Section 3.2.1 Horizontal Datum
- In addition to the NAD83 CSRS version 6 and version 7 discussion. There is also a NAD83 (original) system that is still found in the Town of Oakville’s dataset. Could this system be included in the discussion as well?
- The vertical datum section (Section 3.2.3) has more details on transformation between the different systems, could similar discussion be included for the Horizontal Datum section?

Section 3.4.1.2. Data Collection at Cross sections
- Hydraulic structures such as bridges and culverts can have significant impact to model results. Please consider including more guidance on collecting data for these structures. One suggestion is to collect at least four cross sections in the vicinity of bridges and culverts: one at the start of the contraction zone upstream of the structure, one at the end of the expansion zone downstream of the structure, and two cross sections at the upstream and downstream face of the structure.
- Suggest including a figure similar to Figure 3-2 to show cross sections locations at hydraulic structures.
- Suggest including a figure similar to Figure 3-3 to show cross section survey of hydraulic structures

Section 3.4.2 Buildings and Structures
- Suggest indicating the survey codes for hydraulic structures in Table 3-3 in a cross section figure.

Section 5.5.2 Map Features
- Suggest including example figures of Ortho-Photo and Line base maps.
- Please confirm if flood hazard/risk maps can be plotted on Ortho-Photo basemaps or are line basemaps still required

Section 5.5.4 Flood Hazard Mapping Details
- Suggest including a map that meets the requirements setout in this section.
- If Ortho-Photo basemaps can be used for floodline mapping, suggest showing examples of flood hazard maps on a Ortho-Photo basemap and a line basemap.