The use of untreated wastewater supplied for irrigation can have negative health and environmental impacts.
Wastewater treatment for irrigation
Wastewater has been used in the irrigation of crops for many years. Though the process is common, few understand the risks involved and the importance of wastewater treatment for irrigation.
Why is wastewater used in irrigation?
Irrigation, or put simply: the application of water to soil to supply moisture for plant growth, is a necessary part of all types of farming.
Natural water resources, such as groundwater, surface water or wells, are not always available for irrigation in rural areas. Instead, wastewater is used in their place. Wastewater has for many years played a vital role in the irrigation process and with the continuing depletion of natural water sources this looks set to increase.
The use of wastewater in irrigation is also becoming more popular to keep up with the incline in the world population and subsequent crop, meat and milk consumption. Though the long-term effects of the process are up for debate, it is a viable alternative when better sources of water are scarce.
However problems can arise if wastewater is not treated before it is used in irrigation.
The impact of untreated wastewater irrigation
Treating wastewater before using it in irrigation is a health protection measure. Untreated wastewater can have serious negative health and environmental impacts. These effects can include:
- Spread of pollutants: untreated wastewater can contain bacteria, viruses and parasites. Consumption of crops irrigated with this water could lead to the contraction of serious diseases.
- Chemicals: the water could have been previously treated with chemicals which are harmful to human health. There is evidence to suggest chemicals in improperly treated water can cause various cancers and other health issues.
- Acid: rust and corrosion in pipes can lead to acid in the water which is harmful if consumed.
- Minerals: excessive calcium or magnesium carbonates can contaminate the water.
The term wastewater also covers water from domestic sources such as toilets and sinks. These will often contain human waste such as urine and fecal matter, which are a breeding ground for disease.
Who is at risk from untreated wastewater irrigation?
Without treatment many people can be at risk when wastewater is used for irrigation.
- Those living nearby to areas being irrigated.
- Anyone who consumes the farmed goods.
- Those handling the crops including farmers and those in the supply chain.
Animals can also be put at risk if they consume the crops or the water. What’s more, the meat and dairy products they then produce could also be contaminated, putting the entire supply chain at risk.
Wastewater treatment for irrigation is a vital part of ensuring crops and animal products produced in areas with few alternative sources for irrigation are safe. Those involved in the process should ensure any wastewater used has been properly treated.
NCH Asia Pacific is dedicated to the production of renewable water systems and can assist in the treatment of wastewater for irrigation when necessary thanks to our extensive knowledge of treatment solutions.