Your request is quite general. I feel that you should restrict your request to unusual weir designs. In that spirit, I wish to make a small contribution.

In Queensland (Australia), we have some unusual weirs. Built in timber crib, these are able to sustain very large head above crest. For example, Cunnigham weir passed safely 7.3-m of head above crest.

I have a Web article on the topic at the following address :
    {http://www.uq.edu.au/~e2hchans/tim_weir.html}

Further photographs of these timber crib weirs are listed on the Internet at :
    {http://www.uq.edu.au/~e2hchans/photo.html#Historical structures}
The story of one failure case is given at :
    {http://www.uq.edu.au/~e2hchans/photo.html#Failures and accidents}

Overall the timber crib weirs have had an excellent reliability record. Some are still in use 80 years after completion. Timber crib weirs were built up to the early 1960s in Queensland.

Since the typical design standards were concrete weirs (with stilling basin), steel-sheet-pile & concrete weirs and RCC weirs. There is anexample at :
    {http://www.uq.edu.au/~e2hchans/photo.html#Modern hydraulic waterworks}
 

I hope that you will post on the Internet the results of your query.

Yours Sincerely

Hubert Chanson

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Hubert CHANSON
Dept. of Civil Eng., University of Queensland
Brisbane QLD 4072, Australia
Ph.: (61 7) 33 65 35 16 - Fax: (61 7) 33 65 45 99
Email: h.chanson@mailbox.uq.edu.au - Internet : http://www.uq.edu.au/~e2hchans
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