Extract Irregular Channels in SewerGEMS in to Civil 3D

Hello,

I'm designing a open channel storm network in SewerGEMS platform. I'm having irregular channel sections and Trapezoidal channels sections in the network.

I want to export my network to Civil 3D. what is the way to do that? (I tried exporting to landxml and then to Civil 3D. but it does not create the correct profile in Civil 3D.).

Thanks 

Sumedha