Sewage from a damaged sewer line in Nogales, Ariz., bubbles up into Potrero Creek. The breach was detected Tuesday.

Courtesy of John Hays//

Nogales, Ariz., has declared a state of emergency after a breach in a cross-border pipeline continues to dump untreated raw sewage outside the city limits into Potrero Creek, which flows into the Santa Cruz River.

As a result of the breach, “millions of gallons of raw sewage and heavy metal contaminants from Mexico are currently spilling out and into the Nogales Wash and the Santa Cruz River,” read the proclamation signed Wednesday by Nogales Mayor John Doyle.

The breach, which could cost more than $5 million to fix, will cause catastrophic pollution of the Nogales Wash and of the Santa Cruz River Basin from Nogales and surrounding areas, officials said.

Doyle asked Arizona Gov. Doug Ducey to “declare an emergency and make available any and all assistance that may be available.”

City public works employees found a partial breach of the International Outfall Interceptor, or IOI, during an inspection Tuesday. A dislodged section of cement, which encases one of the manhole accesses to the sewer line, partially sheared the pipe below the waterline, about 200 yards north of the intersection of Old Tucson Road and the Nogales Wash.

Santa Cruz County Health Services is advising people who live in areas where there is water running in the wash and tributaries east of the Nogales Wash to keep out of those areas.

City Manager Carlos Rivera said there’s so much water at the moment that authorities can’t get to the breach, and fixing it is outside the city’s capabilities and resources.

They don’t know yet how extensive the break is or exactly when it happened, but he said it was probably after heavy rains on Friday which caused the Nogales Wash to overflow in some places.

Sewage can be seen bubbling out of the north-flowing creek and cascading down some boulders. Rivera said they also found two breaks on the Mexican side on Wednesday.

“There’s sewage in that wash regardless of this break on this side of the border,” he said. “It’s nothing new; it happens every single day.”

The IOI is a 30-inch sewer trunk line that carries 12 to 14 million gallons of raw sewage a day from from Nogales, Sonora, to a treatment plant about nine miles north of the border in Rio Rico. The 42-year-old pipeline runs about three feet below the bottom of the Nogales Wash and over time has developed cracks and half of its thickness has eroded.

When it rains, groundwater infiltrates the pipe and increases the volume in the wastewater system.

IOI has had major failures over the years, some of which impacted the Santa Cruz River, according to the Arizona Department of Environmental Quality, which sued the International Boundary and Water Commission in 2012 for allowing untreated industrial wastewater to cross the border at Nogales.

“The wastewater that originates in Mexico is also industrial which is difficult, if not impossible to treat,” Henry Darwin, director of the department, said in 2013. “So if the IOI breaks, the water can be contaminated with chemicals, too.”

The city of Nogales and the U.S. section of the International Boundary and Water Commission are responsible for maintaining the sewer line, but who is responsible for what and who pays for it has been the source of debate for many years.

The problem has been so dire, Arizona’s congressional delegation has sent letters to the Department of State and in March introduced the Nogales Wastewater Fairness Act to help the city of Nogales avoid a $40 million repair bill, but it’s still in committee.

Sen. Jeff Flake said in a written statement that he and Sen. John McCain are coordinating efforts “to ensure that IBWC and the city of Nogales share the appropriate level of responsibility for the upkeep and repair of the wastewater and stormwater systems serving communities on both sides of the border.”

The International Boundary and Water Commission has said in the past that the cost should be split 50/50 with the city of Nogales. The commission is a binational agency which governs cross-border issues between Mexico and the United States.

Lori Kuczmanski, spokeswoman for the commission, said the city of Nogales is taking the lead on this latest issue and she could not comment on the cost-sharing or funding issues due to litigation, but added that they are still in discussions with the State Department.

Before finding the breach outside the city limits, sewer workers on Monday discovered part of the IOI had been exposed along Hohokam Drive within the Nogales city limits. City officials said a contractor was hired to do bank erosion work in an effort to prevent potential failure of the international sewer line through future floodwaters coming from Mexico.

In response to the exposed pipeline along Hohokam, where it didn’t break, the commission told Nogales city officials that it appeared the recent erosion of the wash was due to lack of maintenance and the city’s responsibility. It asked for additional information and offered technical assistance. Kuczmansk said they are working with the city and county, taking water quality samples, conducting inspections in the field and attending meetings.

The city maintains that the pipeline should mostly be the responsibility of the international commission since most of the sewage, between 80 and 90 percent, comes from Mexico, Rivera said.

“We’ve been fighting this fight for decades with the IBWC to deal with this problem, but the city doesn’t have the means or capability to deal with it,” he said. The city’s sewage budget is about $2.5 million, he said, and they recently had to increase the rate because they were in the red.