associated with wastewater-irrigated products
include excreta-related pathogens, toxic chemicals (Ensink et al. 2008; Fuhrimann et al. 2016)
concerning (mainly) human health as well as
nitrate and salinization concerning environmental
health (e.g., Jampani et al. 2018). It has been
estimated that in 2016, approximately 93.3% of
the total fecal sludge and wastewater generated in
India was released into the environment without
treatment, resulting in pollution of water bodies
and other environmental and health disasters. It is
estimated that in 2025, 80.5% of the fecal sludge
and wastewater generated will be unsafely disposed into the environment and thus only 19.5%
will be effectively treated. There is no substantial
reduction in unsafe disposal forecasted for 2025
when compared with 2016 data (Borda and CDD
Society 2017).
Currently, irrigation accounts for more than
80% of India’s water use. However, growing
demand for other applications, such as municipal
and industrial uses, is putting increasing pressure
on water availability, especially in and around
urban and peri-urban areas. The projections for
2050 show aggregate water demand increasing to
1,447 m
3 and while agriculture retains its relative
dominance, other uses are projected to increase
their relative share. With rising water stress and
water exploitation, a 50% deficit between water
demand and supply has been predicted by 2030.
Thus, the overall analysis of water resources
indicates that in the coming years, there will be a
double-edged problem—the reduced availability
of freshwater and increased generation of
wastewater due to the increasing population,
food production, and industrialization. In such a
scenario, the use of wastewater for irrigation
would become an inevitable and sustainable
option, especially in arid, semi-arid, and poor
peri-urban areas, primarily because of its high
nutrient content and the scarcity of freshwater
sources—as already practiced in many regions
worldwide (Hettiarachchi and Ardakanian 2016).
In the case of vegetable cultivation with
wastewater, there can be a considerable aggregate benefit for society in terms of year-round
production for farmers and a more balanced diet
for consumers. However, both these stakeholders
are potentially at risk of adverse health effects
from untreated wastewater (Jiménez and Navarro
2013). Irrigation with untreated wastewater is
associated with major health risks such as
intestinal nematodes. While treatment reduces
this risk, there is no single best strategy and each
situation requires its own specific approach to
health protection (Strauss 1991).
It is against this background that the CDD
Society, a not-for-profit organization working in
the space of sanitation, decided to conduct a
study in the Hubli and Dharwad region where
farmers have been practicing wastewater irrigation for decades, under a lighthouse project
called Nexus. The main purpose of the study was
to understand the existing practices of wastewater irrigation and assess the benefits and risks
associated with its usage. The project aimed to
demonstrate the interlinkages between sanitation,
food, water, energy, and health. This nexus of
sanitation and agriculture can provide solutions
for food production in poor peri-urban areas
through the safe use of nutrient-rich wastewater
in agriculture. On the one hand, this approach
improves the sanitation situation by minimizing
the health risks imposed by untreated wastewater, so that a favourable environment for food
production is created. On the other hand, it aims
to increase the supply of food by using nutrientrich wastewater for food production. The main
objective of the current study was to improve the
sanitation situation, provide better health,
increase food supply, and reduce environmental
degradation. There is a great need and potential
for the scaling up of safe practices of wastewater
use in agriculture to reduce stress on diminishing
freshwater resources, improve soil quality, and
reduce food miles in urban and peri-urban areas.
The main objectives of the study are: (1) to
review existing wastewater use practices and
assess the health hazards associated with
wastewater irrigation, (2) to identify the existing
control measures and document the best practices
to mitigate the risks, and (3) to recommend
contextual safety measures for the use of
wastewater in agriculture. This study documents
the best practices followed by farmers in the periurban areas of Karnataka while recommending
40
G. Ramakrishna and M. Hanisch
include excreta-related pathogens, toxic chemicals (Ensink et al. 2008; Fuhrimann et al. 2016)
concerning (mainly) human health as well as
nitrate and salinization concerning environmental
health (e.g., Jampani et al. 2018). It has been
estimated that in 2016, approximately 93.3% of
the total fecal sludge and wastewater generated in
India was released into the environment without
treatment, resulting in pollution of water bodies
and other environmental and health disasters. It is
estimated that in 2025, 80.5% of the fecal sludge
and wastewater generated will be unsafely disposed into the environment and thus only 19.5%
will be effectively treated. There is no substantial
reduction in unsafe disposal forecasted for 2025
when compared with 2016 data (Borda and CDD
Society 2017).
Currently, irrigation accounts for more than
80% of India’s water use. However, growing
demand for other applications, such as municipal
and industrial uses, is putting increasing pressure
on water availability, especially in and around
urban and peri-urban areas. The projections for
2050 show aggregate water demand increasing to
1,447 m
3 and while agriculture retains its relative
dominance, other uses are projected to increase
their relative share. With rising water stress and
water exploitation, a 50% deficit between water
demand and supply has been predicted by 2030.
Thus, the overall analysis of water resources
indicates that in the coming years, there will be a
double-edged problem—the reduced availability
of freshwater and increased generation of
wastewater due to the increasing population,
food production, and industrialization. In such a
scenario, the use of wastewater for irrigation
would become an inevitable and sustainable
option, especially in arid, semi-arid, and poor
peri-urban areas, primarily because of its high
nutrient content and the scarcity of freshwater
sources—as already practiced in many regions
worldwide (Hettiarachchi and Ardakanian 2016).
In the case of vegetable cultivation with
wastewater, there can be a considerable aggregate benefit for society in terms of year-round
production for farmers and a more balanced diet
for consumers. However, both these stakeholders
are potentially at risk of adverse health effects
from untreated wastewater (Jiménez and Navarro
2013). Irrigation with untreated wastewater is
associated with major health risks such as
intestinal nematodes. While treatment reduces
this risk, there is no single best strategy and each
situation requires its own specific approach to
health protection (Strauss 1991).
It is against this background that the CDD
Society, a not-for-profit organization working in
the space of sanitation, decided to conduct a
study in the Hubli and Dharwad region where
farmers have been practicing wastewater irrigation for decades, under a lighthouse project
called Nexus. The main purpose of the study was
to understand the existing practices of wastewater irrigation and assess the benefits and risks
associated with its usage. The project aimed to
demonstrate the interlinkages between sanitation,
food, water, energy, and health. This nexus of
sanitation and agriculture can provide solutions
for food production in poor peri-urban areas
through the safe use of nutrient-rich wastewater
in agriculture. On the one hand, this approach
improves the sanitation situation by minimizing
the health risks imposed by untreated wastewater, so that a favourable environment for food
production is created. On the other hand, it aims
to increase the supply of food by using nutrientrich wastewater for food production. The main
objective of the current study was to improve the
sanitation situation, provide better health,
increase food supply, and reduce environmental
degradation. There is a great need and potential
for the scaling up of safe practices of wastewater
use in agriculture to reduce stress on diminishing
freshwater resources, improve soil quality, and
reduce food miles in urban and peri-urban areas.
The main objectives of the study are: (1) to
review existing wastewater use practices and
assess the health hazards associated with
wastewater irrigation, (2) to identify the existing
control measures and document the best practices
to mitigate the risks, and (3) to recommend
contextual safety measures for the use of
wastewater in agriculture. This study documents
the best practices followed by farmers in the periurban areas of Karnataka while recommending
40
G. Ramakrishna and M. Hanisch