×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

*
*
*
*

Thanks. We have received your request and will respond promptly.

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Sources on Area relationship between watersheds

thread162-437498

Sources on Area relationship between watersheds

Sources on Area relationship between watersheds

(OP)
Hey there,

I am working on an update for a hydrologic study of a big catchment, which was originally studied in the 90s. In the original studies, the mean daily flows for some subcatchments (e.g between river junctions or between dam site alternatives along the main river) are calculated using simple area relationships. in the style:

Qsubcatchment2 = Qsubcatchment1 / Asubcatchment1 * Asubcatchment2

I guess there is some kind of law or source where this propotionality between catchments and subcatchments is referenced or explained. Can someone recommend a source?

Anybody around here familiar with this kind od calculations? or did these guys just simplify the calculations a bit too much?

Thanks for any help!

RE: Sources on Area relationship between watersheds

Assuming that each area has the same Curve Number, the runoff volume will be proportional to the area. But getting a full hydrograph (or even the peak flow) is not a simple ratio, and will depend on other factors, especially the time-of concentration. As you suggest, they simplified the calculations a bit too much!

Peter Smart
HydroCAD Software
www.hydrocad.net

RE: Sources on Area relationship between watersheds

runoff volume and peak flows are also related to length of flow path, time of concentration, elevation and to aerial reductions among other things, so this method is only suitable for very rough / feasibility level analysis. It might be suitable to develop an envelope curve for minimum and maximum runoff as a function of area. These sorts of envelopes do exist, for specific regions and are useful for checking how reasonable the runoff estimate is. For instance:



Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login

Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now
Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close