In the 1960s, songwriter Bob Dylan suggested you didn't need a weatherman to tell which way the wind was blowing, and it turns out he was right. If you live in Harmar or Oakmont, all you need is a piece of ribbon and two waste water treatment plants.

That's the word from the manager of the Harmarville plant of the Allegheny Valley Joint Sewage Authority, who says the unusual weather this summer is to blame for unusually strong sewage odors. But the odors may not be coming from the Allegheny Valley plant alone.

An objectionable smell near the Hulton Bridge has residents on both sides of the Allegheny River wondering from whence it came. The bridge connects Oakmont to the Harmarville section of Harmar. Residents of both communities have noticed the smell, especially during warm weather.

The Hulton Bridge sits about a half-mile south, or down river, from the Allegheny Valley Joint Sewage Authority's plant in Harmarville and nearly another half-mile north, or upriver, from the Oakmont sewage authority plant.

"I've lived in Harmar Township for 32 years," said Marilyn Steenburgh. Ms. Steenburgh works near the Allegheny Valley plant at 2400 Freeport Road and travels the road daily. "It smells terrible at times. I don't know how the people who live there stand it." Offensive odors are not constant, she said, but, "at times it just takes your breath away."

Complaints about the smells are nothing new.

The latest were heard Oct. 1 at the Oakmont council meeting. Melony and Cary Mostel have lived in their Morris Street home for three years. Mrs. Mostel graduated from Riverview High School in Oakmont.

There was always a smell at times, Mrs. Mostel said, but nowhere near as strong as it is now.

"This summer it was the worst it's ever been," she said. "We've had friends come to visit from Grove City and Butler, and when they sit on that bridge in traffic, they can really smell it."

"We've known for years in our community that when you're on Freeport Road, crossing the bridge … you smell the odor," said Oakmont council President Michael Federici. "It dissipates somewhat quickly once you cross the bridge."

Complaints about sewage smells aren't a major issue in Oakmont, he said, but residents have commented to him about it from time to time during his years on council. "We're certainly aware of it in Oakmont," he said.

Barbara Noll, chairwoman of the Harmar supervisors, said occasional complaints have been made, but "it's not a problem as far as we're concerned."

Summer is the worst time for complaints, she added, and Harmar supervisors have contacted the Allegheny Valley authority about them.

Although Oakmont's waste water treatment plant is on Ann Street in the borough, Mr. Federici said when it comes to smells, all indications seem to point to the Harmarville facility. Depending on the prevailing winds, he explained, odors are strongest north of the bridge, affecting the neighborhood across the river from the plant.

"I can tell you without hesitation the Oakmont treatment facility generates no such effects at all," he said.

A solution, he suggested, might be found if both sides sat down and discussed it in a neighborly way. "It's really a bit of a mystery what's causing this, and it's been going on for years."

Someone who is looking for a solution is Joe Rakawski, superintendent of Oakmont's waste water treatment plant for the past 15 years.

He said he receives complaints about smells coming from his plant less than a half dozen times a year and those usually can be traced directly to cleaning and maintenance or a temporary malfunction.

"Every treatment plant that's ever been built has had complaints," said Mr. Rakawski, who previously worked at the sewer authority in Monaca.

Oakmont's sewage collection system was built in the 1950s and has undergone regular updates to meet federal and state regulations. Most recently, a roughly $1 million upgrade replaced some sewer lines in the borough and improved a pump station on Washington Avenue, Mr. Rakawski said. This was done to meet new requirements to separate storm water and waste water collection systems, he said.

Other improvements include a $2.4 million project in 2004 and jobs costing $200,000 to $300,000 to increase plant capacity and to add or rehabilitate equipment. Other projects, such as a new blower system and computer upgrades, have been done to control costs. Covers installed on some tanks may help control odors, but they were installed mainly to maintain heat in the winter.

The Oakmont plant is one-fifth the size of the Harmarville facility and serves only Oakmont proper, Mr. Rakawski said. It's designed to serve 1.6 million customers and does not have the capacity to accept septic tank waste, something that generates revenue for the Harmarville plant.

Rich Chiavetta is the plant manager at the Allegheny Valley Joint Sewage Authority plant, which treats 4.3 million gallons of sewage a day. The plant serves Cheswick, Harmar, Indiana Township, Richland, West Deer and Springdale township and borough.

Like all treatment plants, the Oakmont and Harmarville plants are inspected annually by the Allegheny County Health Department. They also must meet state and federal regulations. In inspections performed this year, including on Sept. 24, the results at Allegheny Valley were good and the inspector smelled nothing, Mr. Chiavetta said.

That doesn't mean odors can't travel off site. "It's the nature of the business we're in," Mr. Chiavetta explained.

The Harmarville facility covers its troughs with aluminum plates to keep odors down. A deodorant system runs from spring through fall, the seasons when odors are intensified. Also, waste burners help to eliminate smells from the methane gas produced by the system.

Weather is a factor, Mr. Chiavetta said. When the nights are cool and the days warm, odors are intensified. It's the same reason the river sometimes smells fishy. "That river smells all the time, but you don't notice it," he said.

Mr. Chiavetta said knowing the direction of the wind at the time complaints are filed goes a long way toward pinpointing responsibility.

"I need to know the wind direction and time so I can identify the source of these odors. If the wind is blowing towards Harmar," he said, "the odor is not ours. If the wind is blowing towards Pittsburgh, it's us," he said. He recommended people determine the direction of the wind by holding a piece of ribbon in the air and make note of the time and date they smell the odor.

The information also will help plant officials determine the source of the problem. For example, Mr. Chiavetta said, sewage could be discharging from a broken line and not be related to plant operations. If an equipment malfunction occurred at that time, that could be the source. "We'll do what we can to control it," he said.

The Harmarville plant has been in operation on the Allegheny River since 1959. At first, it was a primary treatment facility, treating sewage only with chlorine. In 1972, the federal Clean Water Act required that all sewage treatment facilities remove 85 percent to 95 percent of all pollutants before discharging treated waste into waterways. That's when secondary treatments systems using a biological process to consume contaminants were installed. Recently, bids have been accepted for a $4.8 million project to remove heavier solids, such as ash, dirt and rocks, from sewage to prevent clogged pipes. About $166,000 of the money will be used to cover the back of the plant's primary tanks to control odor. A study conducted by plant officials determined this is one area that releases hydrogen sulfide odors.

"Anybody that tells you that we stink every day is not being honest," Mr. Chiavetta said. Local residents can check with the county health department and see there are not that many complaints, he added. "We're not doing a bad job at all if we're only getting one complaint a year."

To report an odor from the Oakmont plant, call 412-828-3244 and specify the date and time the odor is detected. To report an odor from the Harmarville plant, call 412-828-7227 and provide the date and time and, if possible, information about wind direction.

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