Incorporated under the Sibu Water Board order, 1959 made under Section 19 of the Water Supply Ordinance, 1959 (Cap. 141) and reincorporated under the Sibu Water Board Order, 1995 made under Section 19 of the Water Ordinance 1994 when the Water Supply Ordinance 1959 was repealed. The constitution of Board was further amended vide Sibu Water Board Order 2002 and Sibu Water Board Order 2005.