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How can treated wastewater be reused for irrigation or groundwater recharge?

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Treated wastewater is a valuable resource that can be reclaimed for irrigation and groundwater recharge, helping to alleviate pressure on limited freshwater supplies.12

Irrigation

Wastewater can be reused for irrigation through direct application, where treated effluent is piped directly to the site of use.2
* Landscape and Recreation: Secondary-treated water is commonly used for irrigating golf courses and landscapes.12
* Agriculture: With appropriate treatment levels, reclaimed water can be used to irrigate certain agricultural crops.1

Groundwater Recharge

Groundwater recharge is a form of indirect reuse where reclaimed water is introduced into aquifers to be stored and naturally purified as it moves through geologic strata. This is typically achieved through two methods:12
* Deep-well injection: Pumping treated water directly into underground aquifers.2
* Shallow surface spreading: Storing water in ponds or basins and allowing it to seep into the ground.12

The level of treatment required depends on the intended use; while secondary treatment is often sufficient for irrigation, higher levels of tertiary treatment are necessary for applications involving higher risks of human contact or ingestion.12