I have quickly reviewed the above document, and have forwarded it to my Director
and Assistant Director, with the following comments.
Overall, I did not find cause for much concern in regards to the Guidelines'
effect on bridges, EXCEPT:
The stipulations restricting the maximum running grade to 6% could become quite
problematic for many bridge applications. It seems that this criteria was
intended for structures made specifically/only for "pedestrian" use (including
those with disabilities), and is not intended to be applied to vehicular
transportation structures such as bridges that may have sidewalks included in
their superstructure.
Perhaps a specific exception should be included to allow the sidewalk maximum
running grade to match that of the adjacent roadway, providing the vehicular
bridge incorporates the sidewalk. Any separate pedestrian bridge (NOT attached
to and NOT a part of the vehicular bridge) would still be required to meet the
6% maximum running grade stipulation.
Please feel free to contact me if you have any questions or if you need
additional information.
Regards,
Mark W. Richardson, P.E.
NHDOT, Administrator, Bridge Design Bureau