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== Maintenaince ==
* Regular inspection and cleaning of the grit / rack and possibly the gutter and sedimentation tank is required during and after storm periods.
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[[Image:tyrweirTyrweir.jpg|thumb|right|150px|Man checking the grid at a Tyrolean weir, Tanzania]]
Dams and water inlet structures in embankments are vulnerable and expensive elements in river-fed water systems. They are easily damaged by floods, underflow, seepage and suffer from build-up of sediment or rubbish in the water. The Tyrolean weir forms a more reliable and cheaper alternative. Water is abstracted through a screen (or inlet) over a gutter, usually made of concrete and built into the riverbed. The screen on the crest should slope downstream (15-30 degrees), to increase flow velocities and prevent sediment carried by the stream from blocking it. From the gutter, water enters a pipeline, which drains into a sedimentation tank and then flows by gravity into the rest of the system.
{| border="1" cellpadding="5" cellspacing="0" align="center"
! style="background:#ffdead;" | Disadvantages
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| valign="top" | More reliable and cheaper compared to dams and water inlet structures in river embankments<br>
| valign="top" | <br>
|}
== Costs ==
* The capacity of the inlet pipe / drain (diameter and gradient) should be 30% more than the design flow and have an uniform gradient to prevent accumulation of sand.
* The sedimentation tank can accumulate 1.5-2 m3 of deposits and allows water to filter for 10 to 30 minutes at very low speed. It is cleaned by washing it out.
== Maintenaince ==
* Regular inspection and cleaning of the grit / rack and possibly the gutter and sedimentation tank is required during and after storm periods.
* The weir itself does not clean or purify the water.
== External links ==
* General Background [http://www.aquaforall.nl www.aquaforall.nl]