ARSESP Approved Tariff Readjustment Index of Four Point Zero Five Percent (4.05%)

SAO PAULO, Aug. 16 /PRNewswire-FirstCall/ -- Companhia de Saneamento Basico do Estado de Sao Paulo - SABESP (NYSE: SBS; BM&FBovespa: SBSP3), one of the largest water and sewage service providers in the world based on the number of customers, pursuant to CVM Rule 358, as of January 3, 2002, and amendments, publicly announces to its shareholders and the market in general that on August 11, 2010, the Sao Paulo State Sanitation and Energy Regulatory Agency (ARSESP) approved the tariff readjustment index of four point zero five percent (4.05%) to be applied over water and sewage tariffs as of September 11, 2010. This index was published on Diario Oficial do Estado Newspaper (D.O.E.) on August 13, 2010.

The aforementioned readjustment is not applicable to the municipalities of Sao Bernardo do Campo, Lins and Magda which are governed by different rules.

Upon the readjustment effectiveness, tariff charts will be available on Sabesp website, www.sabesp.com.br, and at all the Company's customer service offices.

SOURCE Companhia de Saneamento Basico do Estado de Sao Paulo - SABESP