4 Wastewater Irrigation: Hubli-dharwad, India

Within the twin city of Hubli-Dharwad approximately 60 million l of wastewater is generated every day: this flows, untreated, from sewers and wastewater nallas (open drains) into the natural watercourses that flow into the city’s hinterland (Hunshal et al. 1997). In the semi-arid climate, where the summer temperatures exceed 35 degrees centigrade and the monsoon rains are erratic and unreliable, the wastewater is an extremely valuable resource for urban and peri-urban farmers and many extract it from the nallas and underground sewer pipes to irrigate their crops. This is considerably cheaper than constructing a borehole, which makes the practice more accessible and attractive to farmers with fewer financial resources. The wastewater also provides an irrigation source during the dry season, which enables farmers to sell their produce for three to five times the kharif (monsoon) season prices (Hunshal et al. 1997), while its high nutrient load increases crop yields and also reduces the need for costly fertilizer inputs.