Keeping the yuck out of rivers
Cities pump billions into sewer projects
Ten workers scuttle around like ants inside the 440-foot steel earthworm eating its way under the nation’s capital.
The workers and their tunnelboring machine — they call it “Lady Bird” after Johnson, the environmentally conscious former first lady — are trying to solve a problem plaguing cities since the Civil War: raw sewage carried by storm water into rivers, streets and basements.
More than 700 cities in the United States were built with a combined sewer system, so wastewater — toilet water, shower water, whatever goes down the drain — and storm runoff flow into a single pipe. When it rains, raw sewage often overflows into streets, basements, rivers and streams.
In Washington, about 2 billion gallons of household waste, oil, trash and chemicals spew into the Anacostia and Potomac rivers and Rock Creek each year. The toxic brew is so bad that in the 24 hours after an overflow, it’s dangerous to even touch the water.
In New York, as little as 1/20th of an inch of rain can overload the system, says Tina Posterli, spokeswoman for Riverkeeper, a clean water advocacy group.
In Washington, the $30 million Lady Bird will burrow 4.5 miles of a 13-mile tunnel system under the city.
Above ground, the work is hardly noticeable, but underground it’s a constant assembly line 24 hours a day, six days a week.
A COSTLY ‘DREAM’
Ten to 12 workers at a time man the machine, running a mechanical arm that uses suction to lift slabs of concrete, spinning them around to secure them along the sides of the tunnel. When the slabs fit together, they form a perfect 80,000-pound ring.
Hydraulic jacks shove Lady Bird forward, grinding up dirt and rock and shooting it out through the tunnel entrance — about 180 truckloads every day.
The cavernous machine crawls forward at a top speed of 4 inches per minute.
The work is expensive and time-consuming. But a growing number of cities being sued by the Environmental Protection Agency for violating the Clean Water Act don’t have a choice.
In the past 20 years, the EPA has gone after more than 50 cities with combined sewers for dumping sewage into waterways. A city generally has 20 to 25 years to sharply decrease their combined sewer overflows. The EPA is targeting the largest cities and communities first.
“People need to care about this because we are talking about sewage, and it’s a major, major public health issue,” says Mark Pollins, director of water enforcement at the EPA.
Washington is spending $2.6 billion to dig tunnels beneath the current sewer system. They will collect overflow and send it to a water treatment plant instead of pouring it into the rivers and flooding Rhode Island Avenue, a vital thoroughfare. Cleveland is spending $3 billion to keep raw sewage out of the Great Lakes. St. Louis, $2.1 billion. Kansas City, $2.48 billion.
“This is certainly the largest program we have ever embarked on,” says Lance LeComb, spokesman for the Metropolitan St. Louis Sewer District.
When St. Louis is done, LeComb hopes to capture 82% of all overflow vs. 65% now.
For cities like Washington and Cleveland, the goals are more ambitious: 96% and 98%.
“We are held to a higher standard by the U.S. EPA than some other cities because we are on the Great Lakes,” says Julius Ciaccia, executive director of the Northeast Ohio Regional Sewer District in Cleveland. “We have beaches
and recreational usage.”
WHO PAYS? YOU DO
For Ciaccia, the biggest challenge isn’t the masterful engineering. It’s keeping the public informed. Water rates are going up 13% every year through 2016 to fund the project.
“People are getting these huge rate increases, and yet they just can’t see what they are getting ” for their money, he says. “People don’t see the work being done.”
Philadelphia and other cities are looking into more environment-friendly, and less costly, options to deal with the combined sewer overflow. That means planting trees and grass and replacing non-absorbent sidewalks with porous surfaces that help rainwater soak into the ground or evaporate.
Washington is considering modifying its plan to incorporate more green options. Water department general manager George Hawkins praises the luscious aesthetics and job opportunities that come with green solutions. But, he says, that alone won’t solve the problem.
“The ground can only absorb so much rainfall, and the sewers will still overflow,” he says. “This system is designed to last 100 years or longer. Getting it right this time is really significant if we want these rivers to be fishable and swimmable in the future.”