Tidal irrigation is the natural subsurface

irrigation Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has bee ...

levee A levee ( or ), dike (American English), dyke (British English; see American and British English spelling differences#Miscellaneous spelling differences, spelling differences), embankment, floodbank, or stop bank is an elevated ridge, natural ...

soils in coastal plains using river water influenced by tidal movements. This method is applicable in (semi-)arid regions at the mouth of large river

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

deltas A river delta is a landform, wikt:archetype#Noun, archetypically triangular, created by the deposition (geology), deposition of the sediments that are carried by the waters of a river, where the river merges with a body of slow-moving water or ...

where there is a significant tidal range. It is achieved by excavating tidal canals from the riverbank into the mainland, allowing river water to flow inland during high tides. During low tides, the canals and soil drain enhance soil aeration. The

river discharge In hydrology, discharge is the volumetric flow rate (volume per time, in units of m3/h or ft3/h) of a stream. It equals the product of average flow velocity (with dimension of length per time, in m/h or ft/h) and the cross-sectional area (in m2 o ...

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. Tidal irrigation efficiently utilizes the periodic movement of tides to naturally push fresh water upstream. 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 Evapotranspiration (ET) refers to the combined processes which move water from the Earth's surface (open water and ice surfaces, bare soil and vegetation) into the Atmosphere of Earth, atmosphere. It covers both water evaporation (movement of w ...

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

References

Land management Irrigation Hydraulic engineering Tides

See also

References