While the Delhi government had been debating on what needs to be done to clean the river, the pollution levels have only worsened. In its book Sewage Canal: How to Clean the Yamuna, published in 2007, the Centre for Science and Environment reported that the Delhi stretch of the river is not only dead but had an overload of coliform contamination. Two years later, the pollution data shows no respite to the river. The 22-km stretch of the Yamuna, which is barely 2 per cent of the length of the river basin, continues to contribute over 80 per cent of the pollution load in the entire stretch of the river. There is also no water in the river for virtually nine months. Delhi, impounds water at the barrage constructed at Wazirabad where the river enters Delhi. What flows in the river subsequently is only sewage and waste from Delhi