The Zauro polder project is an irrigation scheme that has long been planned for the Rima River floodplain in Kebbi State, Nigeria. The project is controversial, and would demand careful management to achieve the planned benefits. Location Kebbi State is mainly covered by Sudanian Savanna, open woodland with scattered trees. It is intersected by the lowlands of the Rima and Niger rivers, which are seasonally flooded. There is a wet season between May and September, with little rain in the remainder of the year. Mean annual rainfall is about . Average temperatures are about , ranging from between April and June. Dams and irrigation schemes have often been proposed to make the abundant water of the rainy season available for farming in the dry season. Plan The project was originally conceived in 1969 as a joint venture between the state government and the federal ministry of agriculture and water resources. The dam would be situated in the floodplain of the Rima River between Argungu and Birnin Kebbi, irrigating of farmland. Crops would include rice, maize, wheat, barley and vegetables such as cow peas, onions, tomatoes, sweet potatoes and Irish potatoes. The dam would also benefit the fishing industry, important in the state. The project would include construction of a reservoir and canals used to irrigate and drain polders, areas of farmland protected from flooding by dikes. After a review of the original design, it was changed to reduce water loss from evaporation in the dry season, and also reduce costs, by replacing the open channels with an aquifer recharge system, using wells to draw water from the aquifer for irrigation. The risk of damage from flooding would be mitigated by the Goronyo Dam upstream in Sokoto State, which would also provide water in the dry season. There have been repeated delays. A July 1995 report noted that the project was in "standstill" status. In March 2003, while campaigning for reelection in Birnin Kebbi, President Olusegun Obasanjo pledged to complete the project. In October 2006 the Federal and Kebbi state governments signed a memorandum of understanding for execution of the project, at an estimated cost of N15 billion. In May 2008 President Umaru Musa Yar'Adua ordered work to start immediately on the first phase of the project, which was now estimated to cost over N18.5 billion. In January 2009 Kebbi State governor Sa'idu Dakingari said work would soon commence. Pilot project