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Photo: Eli Degani
Wastewater Treatment
and Recycling treated
wastewater for Agriculture
The treatment of wastewater and its recycling for agricultural
irrigation is an extremely important solution for the water
shortage problem. Mekorot treats about 160 million cubic
meters of wastewater per year, totaling about 35% of the
wastewater in Israel.
In total about 430 million cubic meters of treated wastewater
are reclaimed in Israel for agricultural use. This makes up
about 85% of Israel’s total wastewater - a world record. Of
this, Mekorot recycles 60% high quality treated wastewater
for irrigating agricultural crops in compliance with the highest
available standards!
Mekorot’s strategic goal for the coming decade is to increase
the use of treated wastewater for irrigation to 90%. To
achieve this goal, Mekorot investigates substantial resources
in developing innovative, advanced technologies - both in
an effort to increase the output and to improve the quality
of the treated wastewater while at the same time reducing
costs. High quality treated wastewater that is used for
irrigating agricultural crops frees up the fresh water that had
previously been supplied to the agriculture sector - for use in
the domestic sector. Thus, this important activity contributes
toward improving Israel’s water balance.
Through recycling treated wastewater to the Negev, Mekorot
accomplishes multiple objectives: optimum utilization of
the treated wastewater, diversion of a greater amount of
freshwater for household and industrial sector consumption,
creation of green orchards and fertile agricultural lands in
areas that were previously arid and barren, reducing the
potential for groundwater pollution due to lack or treatment
and non-disposal of wastewater, and providing a solution to
the problem of the pollution of coastal waters as a result of
the direct discharge of raw sewage into the sea.
Wastewater treatment
Wastewater treatment is typically a four-stage process:
pretreatment, primary treatment, secondary treatment and
tertiary treatment. Mekorot’s activities in its wastewater
treatment facilities integrates novel physical, chemical and
biological techniques based on the principle of putting
microorganism sludge in contact with high-load wastewater
while providing a massive supply of oxygen (aerobic
conditions). This process drastically shortens the time it
takes for the natural treatment to take place: from weeks
or months to less than 24 hours, at the end of which we are
left with high quality secondary treated wastewater, which
is suitable for limited irrigation of agricultural crops.
In addition to improving the water balance, wastewater
treatment is extremely important for preserving the
environment, for maintaining the biological balance and
for reducing groundwater pollution. Besor reservoir
Ofer Levy