Syphon irrigation. - - Technical Assistance to the Upper and Middle Sao Francisco Irrigation Project.: FAO/UTF/BRA/026/BRA. The Sao Francisco Valley is located in the northeast part of Brazil and occupies an area of 64 million ha. Its agricultural potential has been estimated at 3 million ha of irrigable land and 27.3 million ha for dry land crops. The region has potential energy of 13.7 million Kw. The UN Food and Agriculture Organization (FAO) is providing technical assistance to CODEVASF (Companhia de Desenvolvimento do Vale do Sao Francisco) in agricultural development, development planning and water resource economics. It is also providing expert services in hydraulic works, geotechnics, design, operation and maintenance of irrigation and drainage networks and pumping stations. (15141-15171).