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.
| Type | Permanently – weekly | 1 – 2 per month | Monthly – yearly | Once per 1 – 5 years |
|---|---|---|---|---|
| Microbiological analysis | E.coli, Salmonella | Helminths eggs, Taenia | Legionella, Giardia, Cryptosporidium | |
| Physic-Chemical, Inorganic | pH, EC, turbidity, TSS, COD, BOD, DO, AOX, total N, NH4, residual Cl2 | SAR, UV 254, DOC, NO3, SO4, Cl Total P | B | |
| Heavy Metals | As, Cd, Cr, Cu, Hg, Ni, Pb, Zn | Al, Ba, Be, Co, Fe, Li, Mn, Mo, Se, Sn, Th, V |
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.
