Help with Design Resources for Small Overflow Weir Design - Hydropower & Microhydropower

[Dersnerman]

Hello All,

I'm working on a feasibility study for an approximately 300kW microhydro site. Design flow is about 200 l/s. For the weir, we are of course interested in flood flows. Let's assume flood flows are 2m3/s (2,000 l/s).

I'm looking for design resources or sample drawings / images for simple overflow weir designs. I'm not looking to complete a detailed design at this stage but I am looking to come up with some well thought out concepts that optimize cost. Most of my previous work has been on larger scale hydro where we had the budget to design everything custom Cast In Place concrete and optimize hydraulics. However for this application, I am trying to think more economically. To perhaps complete the smaller volume intake box/forebay structure using CIP, while using other methods for the larger overflow wier such as gabions, lock blocks, earthfill embankment, or combination. Proper hydraulic sealing would of course be required. I don't like the idea of gabions but I know others have used them for weirs.

Has anyone ever seen lockblocks used for something like this? They would be a particularly economical materials since it's quite easy to truck in lockblocks, but CIP concrete is difficult and expensive, in this particular location.

Any help with resources or just comments / thoughts appreciated!

Cheers,

 

[fel3]

The US Bureau of Reclamation published a book in 1978 titled Design of Small Canal Structures. You can download a PDF of the book here:

https://www.usbr.gov/tsc/techreferences/mands/manuals.html

(it's partway down the page). Chapter V, Part E covers weirs. I haven't read this section of the book in ages, but I just finished skimming it and it looks like it might be helpful.

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"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill

 

[Dersnerman]

Thank you fel3 for the resource!

 

[gbam]

Another great resource is the Handbook of Hydraulics 7th Ed. (Brater, King, Lindell, Wei)