Tidal irrigation

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Tidal irrigation is the subsurface irrigation of levee soils in coastal plains with river water under tidal influence. It is applied in (semi) arid zones at the mouth of a large river estuary or delta where a considerable tidal range (some 2 m) is present. The river discharge must be large enough to guarantee a sufficient flow of fresh water into the sea so that no salt water intrusion occurs in the river mouth.

Irrigation artificial application of water to the land or soil

Irrigation is the application of controlled amounts of water to plants at needed intervals. Irrigation helps to grow agricultural crops, maintain landscapes, and revegetate disturbed soils in dry areas and during periods of less than average rainfall. Irrigation also has other uses in crop production, including frost protection, suppressing weed growth in grain fields and preventing soil consolidation. In contrast, agriculture that relies only on direct rainfall is referred to as rain-fed or dry land farming.

Levee Ridge or wall to hold back water

A levee, dike, dyke, embankment, floodbank or stopbank is an elongated naturally occurring ridge or artificially constructed fill or wall, which regulates water levels. It is usually earthen and often parallel to the course of a river in its floodplain or along low-lying coastlines.

A coastal plain is flat, low-lying land adjacent to a sea coast. One of the largest coastal plains is located in southeastern United States. The Gulf Coastal Plain of North America extends northwards from the Gulf of Mexico along the Lower Mississippi River to the Ohio River, which is a distance of about 500 miles (800 km).

The irrigation is effectuated by digging tidal canals from the river shore into the main land that will guide the river water inland at high tide.

For the irrigation to be effective the soil must have a high infiltration capacity to permit the entry of sufficient water in the soil to cover the evapotranspiration demand of the crop.


Evapotranspiration (ET) is the sum of evaporation and plant transpiration from the Earth's land and ocean surface to the atmosphere. Evaporation accounts for the movement of water to the air from sources such as the soil, canopy interception, and waterbodies. Transpiration accounts for the movement of water within a plant and the subsequent loss of water as vapor through stomata in its leaves. Evapotranspiration is an important part of the water cycle. An element that contributes to evapotranspiration can be called an evapotranspirator.

At low tide, the canals and the soil drain out again, which promotes the aeration of the soil.

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Tidal River (Victoria) perennial river of the West Gippsland catchment, located in the Wilsons Promontory region of the Australian state of Victoria

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Jetty Low bank stretching from the shore into a water span

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Zhengguo Canal canal

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Suisun Marsh

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Couesnon river running from the département of Mayenne in north-western France

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Rhine–Meuse–Scheldt delta river delta in the Netherlands and Belgium

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Irrigation in Iran covers 89,930 km2 making it the fifth ranked country in terms of irrigated area.

Tidal barrage dam-like structure used to capture the energy from masses of water

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Barrage (dam) type of dam

A barrage is a type of low-head, diversion dam which consists of a number of large gates that can be opened or closed to control the amount of water passing through. This allows the structure to regulate and stabilize river water elevation upstream for use in irrigation and other systems. The gates are set between flanking piers which are responsible for supporting the water load of the pool created. The term barrage is borrowed from the French word "barrer" meaning "to bar".

Muthupet Lagoon

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Ennore creek is a backwater located in Ennore, Chennai along the Coromandel Coast of the Bay of Bengal. It is located in the zone comprising lagoons with salt marshes and backwaters, submerged under water during high tide and forming an arm of the sea with the opening to the Bay of Bengal at the creek. The zone is spread over an area of 4 km2, and the creek covers an area of 2.25 km2. It is located 20 km north of the city centre and 2.6 km south of the Ennore Port, and the creek area stretches 3 km into the sea and 5 km along the coast. The creek is nearly 400 m wide, elongated in northeast-southwest direction and merging with the backwater bodies. Once a flourishing mangrove swamp, the creek has been degraded to patches in the fringes mainly due to human activities in the region. The depth of the creek varies from 1 to 2 m and is shallow near the mouth. The north–south trending channels of the creek connect it with the Pulicat Lake to the north and to the distributaries of the Kosasthalaiyar River in the south. The northwestern part of the creek merges with the tidal flats. The soil in the region is of loamy and alluvial types. Most of the area consists of tracts of alluvial soil and the eastern region comprises beach dunes, tidal flats and creek. The creek is oriented from west to east and opens into the Bay of Bengal to the east at Ennore. The creek acts as an outlet for the excess water from the Poondi Reservoir. The creek separates the town of Ennore from the Ennore Port located in the north and the Kattupalli Shipyard located further north. The North Chennai Thermal Power Station is located at the north of the creek and the Ennore Thermal Power Station is located to the south. The creek is part of the Pulicat water system, including the Pulicat lagoon and the Buckingham Canal. As per the 1991 Coastal Regulation Zone notification, the entire Pulicat water system is designated CRZ I. The creek is experiencing siltation due to emergence of the Ennore Port.

Floating dock (impounded)

A floating dock, floating harbour or wet dock is a dock alongside a tidal waterway which maintains a 'constant' level, despite the changing tides.