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{{Language-box|english_link=Water Portal / Rainwater Harvesting / Surface water / Tyrolean weir | french_link= Coming soon | spanish_link= Coming soon Toma Tirolesa | hindi_link= Coming soon वाटर पोर्टल / वर्षाजल संचयन / सतही जल / टाइरोलीन मेड़ | malayalam_link= Coming soon | tamil_link= Coming soon | korean_link= Coming soon | chinese_link=提洛尔堰 | indonesian_link= Coming soon Bendungan Tyrolean | japanese_link= Coming soon 水のポータルサイト／雨水貯留／表面水／チロリアン式堰 }}
[[Image:Tyrolean_weir_icon.png|right|80px]]
[[Image:Tyrolean weir.JPG|thumb|right|200px|Tyrolean weir|Man checking the grid at a Tyrolean Weir. Tanzania. Photo: D. Bourman, Aqua for All.]]
A '''Tyrolean weir ''' is a water inlet structure in which water is abstracted from the main flow through a screen over a gutter. The gutter is usually made of concrete and built into the river bed. 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.
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.