The Kundu River is a tributary of the Penna River in the Rayalaseema region of Andhra Pradesh, India. Originating as a spring near the village of Uppalapadu in Orvakal Mandal of Kurnool District, it goes through many changes before merging with the Penna at Adinimmaya Palli village of Kadapa District. It is known for frequent floods that bring heavy damage to the Nandyal and Koilkuntla areas, and hence it is popularly called the "Sorrow of Nandyal." But nowadays Nandyal town became a big town with huge population so that the drainage water is discharged to the Kundu river with out prior treatment. Industrialists focused their vision at more and more profits and they polluted the river to the maximum extent. The villagers who are living at down flow of the river from Nandyala are suffering with different skin diseases. The pollution impacts even animals health too. In ancient times this river was known as the Kumudvathi. There is a saying in Rayalaseema that whoever drinks the water of the Kundu will gain enormous courage to face enemies. The valley of the Kundu is known as Renadu and is symbolic of the term "Renati Pourusham."
The Kundu River drains around 6,000 acres (24 km2) in its flood plains, consisting of 41 villages. It covers 6 assembly constituencies in Kurnool and Kadapa districts. Many streams and brooks, including the Galeru, Paaleru, Nippuvaagu and Sankalavaagu, are the main sources of flood water. Galeru and Paaleru in particular bring heavy flood water from the Nallamala hills. The Kundu is ferocious in the rainy season, particularly during cyclones.
The villages and the Nandyal town located close to the Kundu river are affected by frequent floods, incurring heavy losses to properties and farmlands. The farmers in this belt are not guaranteed crops until harvested, as no one can predict the precise arrival of floods. From July to December there are several instances of flooding on this river. In 1994 floods incurred around ₨.60 crores of loss. On August 20, 2000, around midnight, the people of Nandyal were inundated with flood water. Almost everyone in the town experienced some loss of property, and 10 people died. In the much-publicised Kurnool floods of 2009, Nandyal was cut off from civilisation for 5 days as the flooded Kundu encircled the entire town.