The Southeast Water Pollution Control Plant on Jerrold Street near the corner of Evans and Third streets processes 80 percent of the city's sewage - that's 67 million gallons a day. Daly City and Brisbane, cities to the south of San Francisco, pump in about 2.6 percent of that total sewage. The Bayview sewage plant is slated to handle additional sewage once the Mission Bay development is completed in the next year or so.

The plant, which was built between 1951 and 1952, began to draw the ire of residents as federal regulations in the 1970s required the city to update its treatment process and reduce sewage spills into the bay. To improve its treatment formula, the city expanded the southeast plant operation from processing one-fifth of the city's sewage from the surrounding district to 80 percent from most of the city's neighborhoods.

The Oakland-based Communities for a Better Environment conducted an air sample analysis at the plant in May 2001 and found chemicals such as Hydrogen sulfide, xylenes, MTBE, toluene and ethylbenzene at levels higher than average. While some of these chemicals are potential health hazards, CBE could not make conclusive statements about the health threat the level of chemicals from the plant may pose.

The Public Utilities Commission is now reconsidering plans to expand the southeast plant operation, but no alternative plan has been proposed.