The Allegheny County Sanitary Authority yesterday approved a 7 percent sewage rate increase for 2010 to fund federally mandated system-wide improvement projects intended to stop untreated sewage overflows into area rivers and streams and daily operating costs.

Beginning Jan. 1, Alcosan sewer rates will increase from $3.77 per 1,000 gallons of water used to $4.04, and the quarterly customer service charge will increase from $7.92 to $8.48. A homeowner using 18,000 gallons of water per quarter will see an increase of $1.81 per month or $21.72 a year.

The federally mandated sewer system improvements could cost $3 billion or more over 20 years. Alcosan's rates have increased steadily and significantly in recent years, climbing 12 percent in 2004, 10 percent in 2006, 8.5 percent in 2007, 9 percent in 2008, and 16 percent last year.

In addition to the Alcosan base charge, 78 of the 83 communities in the authority's service area assess additional charges for community-owned sewer line repair, replacement and maintenance.

Located along the Ohio River on Pittsburgh's North Side, Alcosan operates 95 miles of interceptor sewer lines and treats an average of 200 million gallons of wastewater daily from 320,000 customers.

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