RIO DE JANEIRO (Reuters) – Brazil’s Rio de Janeiro state plans an auction in December for parts of its water and sanitation utility, known as Cedae, that failed to find a buyer during a previous bidding round in April, the governor said on Tuesday.

In the April auction, Rio successfully privatized three of the four Cedae concessions it put up for sale, with the state raking in some 22.7 billion reais ($4.4 billion).

In the new bidding round, the state will modify the unsold concession, which is less secure and more rural than the other blocks, Governor Claudio Castro told journalists. At least nine municipalities will be added to the concession, which originally included seven municipalities, in part or in whole.

“The technical bodies have indicated that (the auction) will be in the first half of December, and I’m working with that date in mind,” Castro said.

In the April bidding round, sanitation operator Aegea, whose investors include Singapore’s GIC and local holding company Itausa SA, bid 15.4 billion reais for two blocks, while rival Igua Saneamento SA, whose investors include Canadian pension fund CPPIB, paid 7.3 billion reais for one of the concessions.

($1 = 5.17 reais)

(Reporting by Rodrigo Viga Gaier; Writing by Gram Slattery; Editing by David Gregorio)