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ENVIRONMENT Resource conservation
rural areas, just under 1% of inhabitants are
connected to a system of this type. However,
the urban connection rate varies greatly
from region to region, and in most provinces
is significantly below the average (Figure 3).
But even in those areas where wastewater is
collected, the necessary wastewater treatment
plants are often lacking (Figure 4). As
a result, only around half of the wastewater
collected in 2006 was purified in a wastewater
treatment plant. The rest is usually
discharged into bodies of water without
treatment, with corresponding consequences
for nature, the environment and water resources.
Due to the special hydro-geological features
of Isfahan Province, it belongs with its connection
rate of 50% to the few Provinces that
are above average. Between 1958 and 1960,
54 km of sewers were laid in the city of Isfahan.
As most of these have barely been
maintained, they must now be renewed
completely.
In the past, with an average wastewater
treatment plant connection rate of 50% – as
high as 80% in cities – Isfahan Province was
a pioneering region within Iran in terms of
wastewater purification. As early as 1967,
Isfahan was one of the first Iranian cities in
which wastewater from 90,000 inhabitants
was purified in a trickling filer plant. Just 15
years later, this wastewater treatment plant
was converted to the activated sludge procedure
and extended to serve 800,000 inhabitants.
A further plant with a capacity of
400,000 inhabitants was later added in
North Isfahan. In 2006, the plant constructed
by Passavant was extended by the
company WABAG to include a further
800,000 inhabitants. Despite these efforts,
a renovation backlog remains for existing
plants, as well as the need for extensions.
Agriculture and industry
As would be expected, the Iranian agricultural
sector is by far the largest consumer of
water. Around 7 million hectares, equivalent
to about half the total area used for agriculture,
is irrigated for farming. An average of
Image 2
POPULATION
DEVELOPMENT
IN URBAN AND
RURAL AREAS,
SOURCE:
Department of
Economic and
Social Affairs,
Population
Division 2007 C
86 billion m3 – or 92.5% – of available water
resources are used for irrigation every year
(see Table 1).
An average 5.5 billion m3 of water is used
for around 240,000 hectares of irrigation
agriculture in Isfahan Province. This means
that in Isfahan Province, about 8% of all
irrigation water is used on just under 5% of
Iran’s total irrigated productive land.
Due to the extreme periods of drought, irrigating
agricultural land has been fully or
partially prohibited in Isfahan and a number
of other provinces for the last few years.
This meant that no water was available for
irrigation in Isfahan Province in 2010. Efforts
to increase the efficiency of agricultural
irrigation by employing innovative irrigation
technologies have not been able to
improve the situation. Instead, they have led
to the continual expansion of cultivated land
and thus to an increase in the amount of
water being exported from the region as
“virtual water” and increased evaporation.
The greatest increase in water demand is
expected to be the result of continuing industrialisation,
even though this process has
so far not reached the expected level in Iran.
In fact, the country’s industrial development
has lost momentum in recent years. Today,
Iran’s industrial demand for water is a mere
1% of the total amount of water used, or
1 billion m3 water per year. However, in Isfahan
Province, the second largest industrial
area in Iran, the share is twice this amount,
and at just under 200 million m3 is around
Water use per sector, 2010 Source: EWRC Table 1
Agriculture Drinking Water Industry Total
Unit billion cbm % billion cbm %
Iran (total) 86 92.5 6 6.5
Isfahan 6.8 92.4 0.4 5.4
2%. Sustainable water management is therefore
a key factor in the economic development
of the region.
Integrated water resources
management in Isfahan
Isfahan Province is one example of the
enormous challenges facing the Iranian
water management industry as a result of a
rapidly growing population, the associated
urbanisation and the increasing effects of
climate change. The Zayandeh Rud flows
through the province and is Central Iran’s
only surface water to flow all year round.
The Zayandeh Rud is the lifeline of Isfahan
Province and provides drinking water for
other cities outside the catchment area, such
as Yazd, which has around 500,000 inhabitants.
Image 3
Sewage
connection rate,
own diagram
Source: NWWEC
30 INTERNATIONAL
2011