7.6 Monitoring Requirements

Another requirement for considering wastewater for irrigation application is the availability of the necessary means, tools, and materials for monitoring treated effluent.

The monitoring requirement of effluent quality standards for irrigation should ideally be clearly outlined within national regulations and standards. In cases where such national regulations and standards are insufficient or absent, internationally recognised guidelines such as the ones outlined by the WHO can be applied.

Common parameters should be sampled more frequently than the costly and less common ones. A general example of a monitoring requirement is provided in the following table.


TypePermanently – weekly1 – 2 per monthMonthly – yearlyOnce per 1 – 5 years
Microbiological analysisE.coli, Salmonella Helminths eggs, TaeniaLegionella, Giardia, Cryptosporidium
Physic-Chemical, InorganicpH, EC, turbidity, TSS,
COD, BOD,
DO, AOX, total N, NH4, residual Cl2
SAR, UV 254, DOC, NO3, SO4, Cl Total PB 
Heavy Metals  As, Cd, Cr, Cu, Hg, Ni, Pb, ZnAl, Ba, Be, Co, Fe, Li, Mn, Mo, Se, Sn, Th, V
Example of the sampling frequency of reclaimed water for reuse in agriculture (A. Steinel, 2011)

According to the WHO guidelines, monitoring should occur at the point of use or effluent discharge. E. coli samples should be taken every two to four weeks, and helminth egg samples every one to two months. Testing of produce for human consumption should encompass E. coli, thermotolerant coliforms, helminth eggs, and heavy metals.

The US EPA (Environmental Protection Agency) recommends installing groundwater monitoring wells to promptly detect any groundwater quality alterations.


For further information, please click on the Materials tab at the top of the page.

Further Reading:

  • WHO Guidelines for the safe use of wastewater, excreta and greywater (Link)
  • JRC Minimum quality requirements for water reuse in agricultural irrigation and aquifer recharge (Link)
  • EPA – Guideline for water reuse 2012 (Link)