The Ajuran also controlled the water resources. They built wells and cisterns on the rivers Shebelle and Jubba. Many of these wells are still working. The rulers also developed a new system of agriculture and taxation, which were used in parts of the Horn of Africa until the 19th century. The later rulers of the Ajuran were not as successful: There were rebellions, and by the late 17th century the empire had fallen apart into a number of smaller states. The most prominent of these was probably the Geledi Sultanate.