Flow path issue

Question

Hi 
 Aqua checking in ORD is great, gives a very good presentation and save a lot time definitely. 
 However, to have it working the flow path need to be right in the first place. 
 In my model, the contours looks good and the flow arrows shows right, but the flow path just stop at nowhere. 
 You could see only one is right, the left of them are all wrong. 
 Same surface I tried it in Inroads / openroads / civil 3d, the flow path all wrong. 
 Anyone got any idea on this? I really want to use this function in ORD. Thanks.

Mark Marnell · Answer

Alex 
 It looks like there are two very thin triangles in the surface, which probably create a little ridge across the surface. As you can see in the attached image, the flow arrows for these triangles are pointing away from the 'centreline', meaning the flow lines are correct - if not what was expected.

Mark Marnell · Answer

Look at the Drawing > Curve > Facet tool. There are several options there which may get you what you want. I am assuming that your data is delivered in 3D DGN/DWG format. 
 If you were working with the Survey module and proper survey data, there is a configuration variable for DWG data (normally contours are curved and contains loads of points). Below is taken from the Help file.

CIVIL_DTM_LINESTRING_FILTER_TOLERANCE

Not enabled by default. Only enable when required, on a project by project basis that has terrain data in DWG format. Filtering looks at 3 points. The Filter max gap is the distance between points 1 & 3. If the distance is within the max gap then point 2 is checked to see if the filter tolerance is within the range. If it is then it is removed.