By Amy Silverman
By Olivia LaVecchia
By Monica Alonzo and Stephen Lemons
By Chris Parker
By Michael Lacey
By Weston Phippen
Under a state regulation expected to take effect by the end of this year, sewer systems must handle nearly two inches of rain in two hours without overflowing. That's a deluge that can be expected once every ten years, but you wouldn't want a storm like that to hit if your sewers weren't ready. The consultant checked 22 of the city's 104 sub-basins and found 19 where sewage flows at least doubled on days less stormy than the new law's standard. The consultant recommended a thorough analysis of the entire system, which would cost less than $1.3 million, a relative pittance. According to the consultant's report, the city didn't want to do it. "That report is in error," insists Padilla. The city, he says, will have a rain study finished in time for monsoon season.
Rainwater enters the system through manholes that don't fit or illegal connections that divert storm water into the sewers. The city's pipes are also porous. More than 90 percent are made of clay manufactured in three- or four-foot segments, and each joint between segments is a potential weak spot, underscored by old design criteria that allowed as much as 10,000 gallons of sewage to leak each day from a mile of brand-new eight-inch pipe. The pipes got even leakier over time as cracks developed in mortar used to seal the joints. Tree roots penetrate the cracks, making them even bigger, and water rushes in during wet weather.
No material is perfect. Plastic, for instance, is prone to bending, which restricts flow. The city says clay is best. "It lasts over 100 years," Padilla says. Other engineers aren't so sure. While sealing techniques have improved over the past quarter-century, clay is brittle. If there's too much traffic on the street overhead, if the ground settles, clay pipes can break.
Bonneau Dickson, a California civil engineer who testifies as an expert witness in lawsuits involving property damage due to defective sewers, says a century is on the high side. "I think that's probably stretching it," he says. "The manufacturers still put out this propaganda. They point out that clay is virtually indestructible -- there are clay sewers from Roman times that are still in service. But the ground shakes from one thing or another; trucks pass over them on busy streets. The mortar at joints breaks up so that the joints become open."
Greenberg, the EPA engineer, says there's no definitive answer to which material makes the best sewer pipe and how long pipes last. "I've actually looked for research on the subject and have not been able to find any really good studies on it," he says. But the EPA has recommended that 2 percent of a system's pipes be replaced each year, essentially saying that sewer pipes can be expected to last for 50 years. Some pipes in Phoenix have been in the ground since 1912.
Gary Harmon, a state environmental engineer who oversees wastewater permits, says he knows one thing for sure.
"Nothing lasts forever."
As the oldest city in the valley, Phoenix faces more sewer headaches than other towns with newer pipes. Just check the number of sewer overflows.
According to Padilla, Phoenix has had 446 overflows in the past five years (spill reports and claims against the city, however, show more than 500, with more than 203,000 gallons of raw sewage rising to the surface). By comparison, Tempe has recorded just eight overflows during the past five years, none over 1,000 gallons.
Cities outside Arizona are in far worse shape.
In Los Angeles, which averaged more than a spill a day during the past decade, the city last year agreed to spend $2 billion to fix its leaky sewer system after an environmental group and the EPA sued, demanding that the city stop overflows. Under pressure from state and federal environmental regulators, Atlanta is spending $3.2 billion to fix its sewers. Louisville is contemplating a $1 billion fix.
These communities have learned the hard way that low sewer rates aren't necessarily a bargain. In Atlanta, for instance, ratepayers may soon see their sewer bills triple to pay for repairs.
"What cities ought to be doing is setting the sewage fees such that money is being put into reserve accounts for maintaining the system in perpetuity," says Dickson. That, he says, would cost the average U.S. ratepayer about $75 a month.
In Phoenix, homeowners pay $15.97, one of the lowest rates in the nation.
The EPA has bigger problems on its hands than Phoenix. "A few years ago, Phoenix, along with several other cities in Southern California and Arizona, got an information request letter from us," says Greenberg, the EPA engineer. "Based on what we got from them, it seemed like they were not having many spills. So we've not done any further follow-up."
Sewer systems don't fail all at once. Rather, it's death by a thousand cuts. Deferred maintenance and crumbling pipes and overloaded lines eventually add up to a crisis that can no longer be ignored. That's what happened in Los Angeles. In Phoenix, it will take lots of cash to prevent the same thing from happening.
Phoenix plans to increase sewer rates by 50 percent over the next five years and hope for the best. Politicians don't get elected on sewer-improvement platforms, and there isn't much glamour in making the first flush to dedicate a new sewer line.