Dave,

Yes, there is not perfect overlap between these guides - and we may have failed to make it perfectly clear about where there is overlap, and where there is not. So, for actual stream crossings, the DOT Core includes elevation data (outlet/inlet inverts, road elevation, etc.) if it is possible to collect the data. But for 'Drainage' crossings, as you have pointed out, elevation data (outlet/inlet inverts, road elevation, etc.) is not something that we suggest gets collected.

I hope this clears up the confusion?

Thanks,

Tom

Tom,

Not needing to know invert angles for Drainage structures, I guess I can see, but I am curious as to why structure length and depth of substrate in the structure and not Drainage measurements.

Also, Structure Slope (%) (p.7) seems different from #44 Structure Slope compared to Channel Slope but I am not clear on which attribute this matches up with. Can you clarify? ***Update - Just discovered that Structure Slope is on iPad, apparently just not on numbered attribute list.

Thanks,

Dave

Dave,

Per the slope question - Structure Slope (%) should have been hidden on the iPad - Chris just informed me he was going to do this. It will be calculated on the backend using structure length, and the outlet and inlet invert elevations. It is something we care about for stream crossings, but not for other crossing types (wetlands and drainages), at least for the moment, as it is something we use in our Hydraulic Capacity modelling.

Parameter # 44, Structure Slope compared with Channel Slope, is used in the Geomorphic Compatibility algorithm, and is simply the visual classification of whether the slopes match - with the options being: higher, lower, about the same.

For the other question, related to structure length, I am asking the DOT.