The water shortages were finally resolved in 1803 when the Euphrates made its way to the city once again. The shift in the river's flow was the product of a century-long effort by the Ottomans to shift the flow of the river, so as to deprive marsh-dwelling tribes like the Khaza'il of the watery environment that allowed them to evade state control. These long-term efforts rendered successful the construction of the Hindiyya Canal in 1793, which further shifted the flow of the Euphrates. These hydrological shifts were to have religious implications. Most notable was the consolidation and spread of Shi'ism. As the shrine city of Najaf gained access to water again, its notables and holy men began to wield considerable power in the area.