Potential drawbacks associated with agricultural irrigation with treated wastewaters from desalinated water origin and possible remedies

Ori Lahav*, Malka Kochva, Jorge Tarchitzky

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

27 Scopus citations

Abstract

Over 90% of the water supplied in the coastal region in Israel in 2013 (600Mm3 y-1) will be from desalination plants. The wastewater generated from this water (>400Mm3 y-1) is planned, after proper treatment, to be reused for agricultural irrigation, making this low-salinity water the main agricultural-sector future water source. In this respect both the Mg2+ concentration and the Sodium Adsorption Ratio value of the water are of concern. We show that the typical Na+ concentration addition to wastewater (between ∼100 and ∼165mgL-1) is much higher than the combined addition of Ca 2+ and Mg2+ (between 0 and several mgL-1). Since desalinated water is typically supplied with low Ca2+ and Mg2+ concentrations (∼35 and 0mg L-1 respectively), the treated wastewater is characterized by very low Mg2+ concentrations, low salinity and very high SAR values, typically >6 and up to 10 (meq L-1)0.5. SAR values can be lowered by adding either Ca2+ or Mg2+ to desalinated water. Adding Mg 2+ is preferable from both health (minimizing cardiovascular disease hazards) and agriculture (inexpensive Mg fertilization) aspects. The low cost of Mg2+ addition at the post-treatment stage of desalination plants corroborates the request for Mg2+ addition in regions where treated wastewater from desalinated water origin is planned to be reused for irrigation.

Original languageEnglish
Pages (from-to)2451-2460
Number of pages10
JournalWater Science and Technology
Volume61
Issue number10
DOIs
StatePublished - 2010
Externally publishedYes

Keywords

  • Desalinated water
  • Irrigated soils
  • Mg deficiency
  • Sodium adsorption ratio
  • Treated wastewater

Fingerprint Dive into the research topics of 'Potential drawbacks associated with agricultural irrigation with treated wastewaters from desalinated water origin and possible remedies'. Together they form a unique fingerprint.

Cite this