HEC-2 data conversion

Hey Chris,

Couldn't let you go a whole week without a question..

I have a HEC-2 data file called Belwilow.dat (attached). The waterway is called Willow Creek, which is a tributary to our East River. It was produced by a neighboring engineering firm up here in Green Bay around 1992.

Through the use of HEC-2, the 100-year profile was computed and the floodway/floodfringe was delineated. Results were then mapped. Since the 1992 flood study, a certain amount of fill material was placed in the floodway zone and has been called into question by our county and the WDNR.

In order to determine the effects of the fill, I'm trying to establish a "baseline model and profile" to which I can add the 'fill' and compare against. I've been given the above mentioned HEC-2 file and paper copies of the accepted profile table.

My problem is that I can't get any sort of geometry, flow, encroachment, IFE data combination to add up to the attached profile table. I have tried to import the data into Boss's HEC2 and HEC-RAS modules as well as trying to use the Army Corp HEC2 with no luck. I think it's understood that the computations differ at bridges and culverts but I thought that I should be able to get a portion of a reach, between bridge sections, to match. Hydraulically speaking, is this a bad assumption? In this case I've been working on XS 10.0 to XS 20.0 and used 590.36 as my downstream boundary condition at XS 10.0. (That # isn't on the scanned sheet.)

Can you tell me if this data file and table are associated? or am I being given bad info?

Once again, thanks for the help.

Pete Diemer
Coastal Planning & Design, Inc.

Dear Pete :

I looked at your data, and it seems that there are quite a few problems with it. For
example, there are negative ground stations defined. However, HEC-2 does not
support these. Also, there are bank stations defined, yet no corresponding ground
station that matches this. This, again is not supported by neither HEC-2 nor
HEC-RAS.

I have enclosed the ASCII text file from RMS that lists the problems that it
encountered in importing the data that you were provided.


Note that we use the original HEC-2 program with RMS. However, you were unable
to get our software nor the standard HEC-2 program to match the results that you
were provided. It seems that you were given bad data from the supplier of this data.
The old axiom "Garbage In = Garbage Out" would apply here.

If you have any additional questions or need any further information, please contact
me again.

Sincerely,

Chris E. Maeder, M.S.
Senior Technical Engineer