Bridge widening issue

[Drew]

I am working on a Bridge widening Hec Ras run. The bridge is being widened to the down stream side. The widening is in the shadow of the bridge and in reality should not effect the water surface profile. But when I do an existing condition vs proposed condition, because I have widened the bridge, the internal cross section for the downstream section of the bridge causes the water surface grade under the bridge to start sooner than the existing condition and continue for a longer bridge width, thus causing the upstream proposed water surface to be higher. How do you resolve an issue like this?

[MattZ]

You can modify the internal bridge cross sections, if that is what you need to represent in the model. In the Bridge Culvert Editor, select Options and Internal Bridge Cross Sections.

You can also make sure that all of your river cross sections are in the same location for existing and proposed conditions.