The biggest public works project in Portland history -- the overhaul of its antiquated wastewater system to divert raw sewage from flowing into the Willamette River and the Columbia Slough -- will come to a ceremonial conclusion next week.

City leaders won't mark the milestone with a polar-bear plunge or celebratory flush. Instead, they'll debut a 12-minute film -- "Working for Clean Rivers," narrated by Lesley Stahl -- at Wednesday's Portland City Council meeting.

-- which included the construction of massive underground tunnels on both sides of the river, a pipeline along the slough and an expanded pump station to carry overflows to a North Portland treatment plant -- has been online since September, with final touches to be wrapped up by Dec. 14.

By any definition, the end has been a long time coming.

Portland launched the project in 1991 under pressure from environmental activists and state regulators. The city set the final budget of $1.4 billion -- paid by Portland ratepayers -- in 2005.

Before, runoff and sewage flowed into the river and slough when storms overtaxed the sewer system -- as often as 50 times a year. As the city grew, "the nature of the runoff became more troubling, and our standards changed," U.S. Rep. Earl Blumenauer, who oversaw the program's inception as a city commissioner, said in a recent interview.

Commissioner Dan Saltzman, who now oversees the city's Bureau of Environmental Services, frequently crows that the project met its deadline and its budget; the final price tag comes to $1.44 billion.

"The Willamette River is sometimes what divides the city," Saltzman said. "It's more often what unites the city. This is something we can all be proud of."

Here's a look at the project by the numbers:

53

: Signs that dotted the east and west banks of the Willamette River in the early 1990s, warning Portlanders to "avoid water contact in this area during and after rainstorms."

50

: Dirty syringes, roughly, that environmental activists collected along the river before the project and carried in a glass container to City Council meetings to illustrate the contamination. "It was a visible image of something that was otherwise invisible," activist Nina Bell said.

6 billion

: Gallons of stormwater mixed with sewage that spilled into Portland's waterways each year in the 1990s.

$15

: Average monthly amount a Portland ratepayer paid for sewer services in 1991.

$55

: Average bill now; about 27 percent pays for the Big Pipe.

24

: Years until ratepayers are done paying for the project.

30

: Workers trained to operate 120 feet underground in pressurized chambers to repair cutterheads on three tunnel boring machines -- Lewis, Clark and Rosie.

13

: Miles of massive pipeline in the new system.

22

: Diameter in feet of the biggest pipes, big enough to drive a TriMet bus through.

Four

: The new annual limit on wastewater overflows into the Willamette during winter. The city has had one so far this year -- Tuesday, because of downpours.

Timeline:



1851:

Portland incorporates and builds a combined sewer and stormwater system that drains into the Willamette River.

1950-51:

Portland builds its first sewage treatment plant near Columbia Boulevard.

1952:

The plant opens.

1970s:

An estimated 10 billion gallons of combined stormwater and sewage spill into Portland waterways each year.

October 1972:

Congress enacts the Clean Water Act.

April 1991:

The nonprofit Northwest Environmental Advocates sues the city over alleged Clean Water Act violations.

August 1991:

Responding to the suit, the Portland City Council approves a plan to cut overflows by 99 percent.



1993:

Portland trims its goal to 96 percent, shaving $300 million from the project's price tag.



1997:

The first major phase of the Big Pipe project, the Columbia Slough Big Pipe, starts.

2000:

Portland completes the Columbia Slough Big Pipe.

2002:

Construction begins on the westside Big Pipe.

2005:

Portland officials peg the cost of the entire program at $1.4 billion.

2006:

The westside Big Pipe is finished, and the eastside Big Pipe gets under way.

2011:

The eastside Big Pipe wraps up.

Nov. 30, 2011:

The City Council will declare the project finished.

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