The National Irrigation Administration (NIA) is a government-owned and controlled corporation primarily responsible for irrigation development and management. It was created under Republic Act (RA) 3601 on 22 June 1963. Its charter was amended by Presidential Decree (PD) 552 on 11 September 1974 and PD 1702 on 17 July 1980. Both increased the capitalization and broadened the authority of the Agency.
NIA's forerunner was the Irrigation Division of the defunct Bureau of Public Works. NIA was placed under the Office of the President (OP) upon its creation. It was attached to the Department of Public Works, Transportation, and Communication under PD No.1, dated 23 September 1972. The issuance also integrated all irrigation activities under the Agency. The Administrative Code of 1987, dated 25 July 1987, attached NIA to both the Department of Public Works and Highways (DPWH), and Department of Agriculture (DA). But NIA remained attached to DPWH. It was transferred to OP pursuant to Executive Order No. 22, dated 14 September 1992. Then, it was attached to DA under Administrative Order No. 17, dated 14 October 1992.
Executive Order No. 165, Transferring the National Food Authority, National Irrigation Administration, Philippine Coconut Authority, and Fertilizer and Pesticide Authority to the Office of the President, 5 May 2014. Memorandum Order No. 70, Providing for the functions of the Presidential Assistant for Food Security and Agricultural Modernization, 5 May 2014.
Memorandum from the Executive Secretary - Office of the President, the Secretary of the Office of the Cabinet Secretary was designated Acting Chairperson of the NIA Board of Directors, 3 November 2016.
After the creation of NIA under RA 3601 in June 22, 1963, there was only one (1) Regional Center for Mindanao situated in Koronadal, South Cotabato. Later on, Mindanao was divided into two (2) regions, Region 7 in Molave, Zamboanga del Sur and Region 8-A at Koronadal, South Cotabato. Region 7 composed the provinces of Zamboanga del Sur, Zamboanga del Norte, Sulu Archipelago, Misamis Occidental, Misamis Oriental, Camiguin Island, Lanao del Sur and was under the supervision of Engr. Jose Arce who was later on replaced by Engr. Depandian Ibrahim. With the issuance of NIA MC No. 12, series of 1978, a new regionalization scheme for Mindanao was created with headquarters in Zamboanga City, Region 7 which was later changed to Region 9 retained the provinces of Zamboanga del Sur, Zamboanga del Norte and Sulu Archipelago. Morever, Zamboanga Sibugay came to be when attempts to divide Zamboanga del Sur was finally enacted in February 2001 by virtue of Republic Act No. 8973. Upon the approval and implementation of the NIA Rationalization Plan in April 2009, an irrigation management office was established in the area.
On August 1, 1989 RA No. 6734 otherwise known as the Organic Act for the Autonomous Region in Muslim Mindanao (ARMM) was enacted into law and based on the plebiscite issued on November 19, 1989, the provinces of Maguindanao, Lanao del Sur, Basilan, Sulu and Tawi-tawi were covered by the ARMM. While the NIA ARMM were not yet established, the provinces of Basilan, Sulu and Tawi-tawi were still under the direct supervision of Region 9 per arrangement with the NIA Central Office. Meanwhile, Executive Order No. 429 dated October 12, 1990 was issued by Her Excellency Corazon C. Auino, transferring the Regional Center from Zamboanga City to Pagadian City but retaining Zamboanga City as the commercial and industrial center. Pursuant to the said Executive Order, Executive Secretary Eduardo R. Ermita issued Memorandum Circular No. 75 dated November 12, 2004 directing the transfer of Regional Offices of all Departments and Agencies from Zamboanga City to Pagadian City as soon as practicable. NIA Region 9 eventually transferred to Pagadian Ciy in two batches dated March 24 2008 and August 19, 2008.
Presently, the region has two Irrigation Management Offices - the Zamboanga del Sur and the Zamboanga Sibugay - and two regional sub-offices which are the Zamboanga del Norte and ZAMBASULTA (Zamboanga-Basila-Sulu-Tawi-tawi).