Over time, these could become quite broad in places, which may explain why the tunnel height varies from 5.5 feet [1.7 m] to as much as 16 feet [5 m] and also how the workers, using oil lamps, could get enough air.
शहर जल - आपूर्ति प्रणाली अपने पानी में से ३० से ५० प्रतिशत, और कभी - कभी तो उससे भी ज़्यादा पानी चू देती है ।