Portland's water rises in a land of mountains and mist, a protected wilderness of beauty where clear, cold streams run as they did when Native Americans drank from them 10,000 years ago.

But after the city's Bull Run water arrives in taps, toilets, showers and industrial pipes, it heads to one place, a place most of us don't think much about. A wastewater treatment plant is a relatively new system of treating urban sewage, where everything must work all the time, day and night. It's an intermediate step in a process of continuous recycling between sky and ocean. If a pipe leaks or a pump quits, redundant machinery, including backup systems of backups systems, averts disaster.

Sewage waits for no one.

Treating waste is not a perfect system, and Portland's program is not unique. Treatment doesn't remove all health hazards, such as heavy metals, chemicals or pathogens. It just accelerates the natural process of decomposition until the treated sewage meets national health standards for recycling it in rivers and on farms.

The Clean Water Act of 1972 set those standards, spurring treatment plants around the country to develop new ways of treating sewage. Experts disagree about whether those standards, set by the Environmental Protection Agency, are rigorous enough to protect public health.

It used to be worse. In the olden days, Portland's raw sewage sloshed down wooden troughs to the Willamette River. Since 1952, when the city built its wastewater treatment plant in North Portland, improvements have arrived every decade, even if raw sewage still ran into the river whenever it rained hard. The latest upgrade came Dec. 1, when the $1.4 billion Big Pipe project went into operation, collecting sewage, stormwater, industrial wastewater and paved-over streams, and moving it all to the plant.

The city's ratepayers know all too well about the Big Pipe -- they are the ones paying for it with some of the country's highest water/sewer bills. In exchange, they're getting a cleaner river. The two big new pipes on either side of the Willamette should reduce sewage overflows into the river by 94 percent.

A long trek

The journey of Portland's wastewater from 614,000 customers begins in a pipe from your house to a sewer line that runs under the middle of your street. Gravity pulls the sewage into increasingly larger pipes down to either side of the Willamette River. From there, really big pipes -- 22 feet wide on the east side, 15 feet on the west -- head north. Along the way, industrial flow and rain and creek water join the surge. A pump station on Swan Island heaves it up and over Willamette Bluff, where it continues to the Columbia Boulevard Wastewater Treatment Plant beside the Columbia Slough in North Portland.

If you live in Sellwood, say, the journey from house to plant takes about three hours at a stately rate of 4 mph. Rush hour, when the plant receives its highest volume, hits around 2 p.m.

Washington County treats sewage from 12 cities and sends the effluent into the Tualatin River. In Clackamas County, treated water from Oregon City, West Linn, Gladstone and other towns flows into the Willamette River. Like Portland, both counties truck sludge to farms in eastern Oregon.

Portland's plant occupies 140 acres of low buildings, pumps, basins, tanks, pools, clarifiers, skimmers, digesters, presses, scrubbers, conveyor belts and hoppers. Their work is to remove physical, chemical and biological bad stuff and produce waste safe enough to return to the environment. Most of the operations are automated; the most crowded room is a computer station where workers monitor levels of sewage and chemicals used to treat the wastewater.

Raw sewage first enters the plant through five underground pipes. Industries are required to reduce toxins such as lead and arsenic to acceptable levels onsite before they enter the sewer system. The smell on the neatly landscaped grounds of the plant is noticeable but not enough to bother a heron flying lazily overhead.

At the first stop, giant rakes scrape off floating debris -- 16 tons a day of cellphones, condoms, false teeth, sticks, rocks, rags -- that gets trucked to the landfill. Grit basins remove sand and fine rocks.

Still underground, sedimentation tanks slow the flow to let solids sink to the bottom. Skimmers remove oil, grease and other stuff that floats.

A sticky situation

Grease is a problem.

It plugs pipes, attaches to roots in sewer lines and causes backups into basements.

"A lot gets here," says Mike Ciolli, operations manager. Gobs of it comes from cooking grease, oil from soap and bodies taking showers and -- the worst culprits -- restaurants and apartment/condo buildings.

The gray-brown water emerges into daylight, where the real party begins. Trillions of microbes -- 10.625 trillion to be exact -- leap into action to break down the material into carbon dioxide, water and methane. Powerful blowers push up to 65,000 daily pounds of microbe-friendly oxygen through bubble defusers. The water roils and boils.

At the last stop are open basins where sweepers scrape the remaining sludge off the floor and it's pumped back into aeration tanks to feed the voracious microbes. Sodium hypochlorite (bleach) disinfects more bugs. Pipes then carry the treated water two miles north where, underneath two small, unmarked buildings beside the Columbia River, sodium bisulphite lowers the bleach content to levels acceptable to the Oregon Department of Environmental Quality.

On rainless days, about 50,000 gallons a minute of treated wastewater flows into the Columbia through pipes that run underground to the middle of the river. That's enough to fill an Olympic-sized swimming pool every 13 minutes. Fishermen know exactly where the outflow occurs because fish gather there to feast on the nutrient-rich water, Ciolli says.

On big rain days, when the increased volume can fill all the tanks, any overflow receives only minimal treatment before flowing into the Columbia. It's a common practice, allowed by the DEQ.

Spills happen. "We fix it, clean it up and report it," Ciolli says.

All of the water that comes into the plant -- 100 percent -- goes into the Columbia. That's a trickle in the river's mighty flow, Ciolli says.

Would he drink it?

"No, but it's river quality."

Elapsed time from house to river: eight hours.

Solids

What happens to the sludge is a different tale. After it's scraped, squeezed, digested and de-watered to the consistency of "wet cake" -- the process takes 15 to 25 days and produces enough methane to supply 42 percent of the treatment plant's energy -- Portland's poop climbs a three-story conveyor belt and drops into two hoppers. Every few hours, day and night, a truck pulls up below the hoppers, fills up and heads to eastern Oregon.

Exactly 200 miles later, each truck, carrying 69,320 pounds of biosolids, rumbles over a dirt road to one of several staging areas the size of a football field on Kent Madison's farm in Echo, a few miles south of Hermiston. Six trucks make two round trips every 24 hours. Madison has been accepting Portland's sludge since 1990.

A front loader scoops up the sludge and fills a manure spreader, and, based on GPS coordinates, heads to the appropriate field. Traveling at exactly 2.5 mph, John Shown hits a stopwatch and shoots "product," as Madison calls it, off the side of the spreader over a 20-foot-wide swath at a rate of 3.8 tons per acre. Seven minutes later, Shown shuts down the empty spreader and heads back for another load.

Sixty or so days later, depending on the season, Madison allows cattle to graze on the fertilized area. The cattle, owned by Wilson Cattle Co. of North Powder, end up as beef sold to restaurants, supermarkets and other outlets in six Western states, says John Wilson, the company's co-owner.

Farmers have applied human-waste fertilizer to their fields for eons, but only relatively recently have cities turned to farmers to dispose of their biosolids. New York, Los Angeles, Chicago, Seattle and numerous other cities apply biosolids to farmland.

Safety questions

Health risks from biosolids are much-studied, producing thousands of academic reports. The U.S. Environmental Protection Agency, which sets what it deems "acceptable" levels of harmful metals, viruses and chemicals in sludge, acknowledges that more study is needed to identify possible new contaminants.

"Is it safe? Yes," says Bob Brobst, an engineer and 30-year biosolids expert who is familiar with Portland's biosolids program. Brobst works in EPA's Denver office. "If it's done according to the regulations, it's safe. Can we improve the regs? Yes, because the regs were done 20 years ago."

The EPA reviews its sludge regulations every two years to identify possible new toxins.

The EPA divides biosolids into two grades: Class A and the less rigorously treated Class B sewage sludge. Class A sludge has been treated to reduce bacteria before spreading it on land; Class B has not. Portland has a Class B treatment plant.

Other entities are unsure about the safety of applying sludge to farmland. A 2002 National Research Council study stated "that while there is no documented scientific evidence that sewage sludge regulations have failed to protect public health, there is persistent uncertainty on possible adverse health effects."

Nina Bell is uncertain, too. Bell is executive director of the Portland-based watchdog agency Northwest Environmental Advocates.

"There is wide evidence that chemicals in airborne sewage sludge, when it dries and turns to dust, cause a whole host of health problems, an issue EPA has repeatedly, and over many decades, attempted to suppress," Bell says. "These are things such as sinus infections, respiratory infections and lung diseases, eye irritations, asthma. We know that these types of health problems have been experienced by people in eastern Oregon just as they have across the country near sewage-sludge dumping sites."

The EPA's Brobst counters: "I would argue that that's founded on fear as opposed to science."

Dean Marriott directs Portland's Bureau of Environmental Services, which manages the plant's operations. He calls the program "an ideal method of recycling biosolids." Some communities burn biosolids and others bury them in landfills, raising questions about air quality and contaminating the water table.

"Any way you deal with biosolids, there are issues," Marriott says. "No way of handling biosolids is completely without risk, but I like the land application the best because it has very, very minimal risk and it recycles the product so that it has value."

A happy farmer

Nationally, about 55 percent of the 7.1 million tons of sewage sludge generated each year is applied on farms. The rest goes into landfill or is burned. All 15,000 annual tons of Portland's biosolids end up on farmland, but Madison is barred by law from applying it directly to any USDA-certified organic produce.

Two-thirds goes on dryland pasture, plus wheat, alfalfa and canola crops on Madison's rolling farm. The rest goes to smaller farms in Wasco County that are closer to Portland, saving hauling fuel. About 5,000 acres of Madison's 17,500 acres receive Portland's biosolids. Salem's and Beaverton's biosolids go on smaller areas of his farm.

As you might expect with fertilizer, biosolids produced lush crops and more forage for cattle on Madison's farm, according to studies by the Bureau of Environmental Services. Grass yield increased 530 percent over an eight-year period covered by the study.

Those benefits keep Madison in the biosolids business, he says.

"We're not just a bunch of yahoos who want to go spread poop," he says. "When you live in 9 inches of rainfall, a desert, anything you can do to improve the soil profile at no cost to you, that's a good deal."

In fact, the city of Portland pays Madison handsomely -- $604,400 a year -- to dump its biosolids. In turn, Madison pays the city back $101,605 for the fertilizer value of the biosolids, netting him half a million dollars each year. In the program's 22 years, Portland has hauled more than 2 billion pounds of biosolids to Madison's farm.

What's more, Madison sells some of his canola -- fertilized by biosolids -- to a company that converts it into biodiesel. The biodiesel helps fuel the trucks that deliver biosolids to Madison's land. Another loop in the journey of Portland's waste.

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