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Headworks layout and cross sections

Short answer

The layout comprises weir bays, divide wall, under sluices, head regulator, guide bunds, and fish ladder. Under sluice crest is at river-bed levele with gates, aprons, and sheet piles. Head regulator crest is 1.2–2.0 m higher, with gates and cutoffs. The weir has a raised crest with shutters, sloping glacis, stilling basin, and pile cutoffs.

Draw a neat sketch of the general layout of a diversion head works and cross sections of under sluices, canal head regulator and weir with all details.

(a) General layout (plan)

 Marginal bund  <------ river flow ------>
 ___________________________________________
 |                                         |
 | Weir bays | DW | Under- | DW | Head reg. |-> Canal
 |~~~~~~~~~~~|    | sluice |    | (gated)   |
 | Fish ladder     | pocket |  silt excluder |
 |_________________|________|_______________|
 Guide bund (u/s)           Guide bund (d/s)
 Upstream apron / Downstream apron, pile cutoffs

(b) Section of undersluice

  Pond level ~~~~~~~~~~~~~~~~~~~~~
  gate  |#|  pier/bridge deck
  ______|#|___                   ___ d/s apron
 u/s    crest (river-bed level)  |   |
 apron  ------------------------ |   | stilling basin
 sheet pile                      sheet pile

Crest at river-bed level; gate fixed above; u/s floor and cutoff; d/s hydraulic-jump floor with glacis, blocks and apron.

(c) Section of canal head regulator

 Pond level ~~~~~~~~~~~~~~~
          |#| gate        deck
   _______|#|______________
  regulator crest (1.2-2.0 m above sluice crest)
   u/s apron | floor | piles | d/s apron -> canal

Crest is higher than the undersluice crest; piers carry gates and a bridge; floor with u/s and d/s cutoffs.

(d) Section of weir

  HFL  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  Pond level ~~~~~~+--+ shutters
         __________|  |\___
  u/s apron  crest   \ glacis   d/s floor
  ________________________      ______ apron
       sheet pile (cutoff)       pile (cutoff)

Weir crest is raised by shutters above the permanent crest; the d/s sloping glacis dissipates energy by a hydraulic jump on the horizontal floor; u/s and d/s sheet piles control seepage; the aprons and filters protect against scour.

✓ Answer checked by Claude Opus 5.5 (high effort)

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