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BUENOS AIRES, Dec 4 (Reuters) - The Argentine province of Santa Fe raised $800 million through the sale of nine-year bonds, its Economy Ministry said on Thursday, with bids reaching more than double the offer.

The provincial government will pay an 8.10% annual interest rate on the debt, the ministry said.

The province had been looking to place up to $1 billion in the deal, a source told Reuters on Wednesday.

A significant portion of interest came from within Argentina, with over 800 local investors offering to buy $350 million worth of the bonds, the ministry said.

Santa Fe's Economy Minister, Pablo Olivares, called the sale a sign of the province's financial health.

"The operation confirms the fiscal strength and institutional solvency of the provincial government to enter international markets under favorable conditions," he said.

The proceeds are set to be used to fund major public works projects, including the construction of large gas pipelines, the modernization of key roads and investments in public safety.

(Reporting by Walter Bianchi; Writing by Kylie Madry; Editing by Daina Beth Solomon and Sarah Morland)

((Kylie.Madry@thomsonreuters.com;))