After 40 straight days of rain, Honolulu city officials elected in 2006 to dump nearly 50 million gallons of untreated sewage into the Ala Wai Canal.

Eventually, after the beaches were cleaned and pipes repaired, the city settled a series of lawsuits by signing a global consent decree to upgrade its sewage system over a period of decades.

But earlier this month, amid the second serious rain storm on Oahu in the last two winters, the system failed again, with three separate sewer overflows in just two days. An estimated 51,000 gallons of combined storm water and raw wastewater ran into a Windward Oahu stream on March 5, then at least 10,000 gallons into Palolo Stream and more than 30,000 gallons into Wailupe Stream the following morning.

Weren’t the consent decree and the work the city’s done to comply with the terms of the deal supposed to stop these types of spills?

“We’re supposed to eventually avoid these,” Environmental Services Director Tim Steinberger said when Civil Beat asked about the spills outside of a Honolulu City Council budget hearing. “It was a lot of rain, it was a lot of rain.”

Steinberger said the consent decree includes fixes to the collection system to be completed between now and 2020, and that the number of spills will come down as the city implements a stronger approach to maintenance and increases spending to replace pipes.

Sewage has taken a lead role in the city’s budget. For example, more than 57 percent of the $578 million Fiscal Year 2013 capital budget falls under the heading of “sanitation.” The single biggest item is $148 million for a 10- to 12-foot-dimeter conveyance tunnel between Kailua and Kaneohe that’s capable of both transferring regular flows and also storing stormwater runoff in the event of heavy rains.

“What makes me confident about the wastewater consent decree is that we have a city administration that’s fully committed to funding it, and executing it,” City Council Public Works and Sustainability Chair Stanley Chang told Civil Beat. “So, it’s part of a plan and it’s part of a plan that will take us to a system that we can be proud of in 25 years, and that’s why I feel confident about our wastewater system.”

But there’s a limit to how much the city will spend on the sewer system. Steinberger said it’s not practical to expect the number of spills to ever be zero.

“You just cannot economically justify, say, capturing two more overflows for, say, a billion dollars. You just can’t do that,” he said.

He pointed to the 50-year and 100-plus-year storms Honolulu experienced last year when garbage- and medical-waste-laden stormwater was released from Waimanalo Gulch Landfill into the ocean.

“So, you know you’re going to have those (wet weather) events, and whenever you exceed those, you’ll most likely have some overflows in the system,” he said. “You can’t design to accommodate everything out there. Otherwise you would have huge 10-foot pipes where you only need an eight-inch pipe on a daily basis.”

Sierra Club Hawaii Chapter Director Robert Harris said the city deserves credit for entering into the consent decree. His organization, one of the state’s largest environmental groups, was among the parties suing the city after the Ala Wai Canal spill and a party to the consent decree.

But, Harris said, the city should aim higher.

“Plainly, zero is the goal,” he said. “I think everyone should agree to that. As far as a working goal of where the city should be.”

Harris said the consent decree was drafted in such a way that if the city is not doing what it promised or if the measures it implements aren’t addressing the problem, the parties do have the ability to go back to court. But he said progress is being made.

“When we first initiated that litigation, we were having nearly a spill a day. And the main cause was poorly maintained sewage pipes that allowed infiltration as a result of rain events,” Harris said. “We’re not there yet, but it’s night and day from where they were.”

Steinberger said 250 sewage overflows per year was not unusual in the late 1980s and early 1990s. Now, the number is down to around 150 per year. Another metric — sewage overflows per 100 miles — shows similar progress, he said.

“You have to keep in mind that we’re in Year 1 or 2 of a 25-year consent decree,” Chang said. “It’s a 25-year, $4.5 billion consent decree, so it’s a really massive project that’s only just begun. And when it’s completed, even then I’m not sure that we’ll have zero incidents, but I think we can expect a much higher level of service.”

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