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July 17th, 2023
Rep. Grijalva Reintroduces Legislation to Fix Longstanding Issues with Nogales Wastewater Pipeline

WASHINGTON – Representative Raúl M. Grijalva (AZ-07) introduced H.R. 4643, the Nogales Wastewater Improvement Act of 2023. The bill would transfer ownership of the International Outfall Interceptor (IOI) to the International Boundary and Water Commission (IBWC) for much-needed infrastructure repairs and future maintenance.

The legislation is critical to prevent raw sewage from spilling into Nogales’ waterways and to ensure Nogales is not burdened with a disproportionate share of responsibility for an international pipeline. The IOI conveys over 10 million gallons of water from Nogales, Sonora and Nogales, Arizona to the International Wastewater Treatment Plant in Rio Rico, Arizona.

“It’s time Congress finally took the necessary steps to end the persistent public health threats surrounding the IOI so that the people of Nogales can rest assured the health and well-being of their families are protected from harmful wastewater,” said Rep. Grijalva. ” Every community should be able to live in an environment that guarantees clean air, water and opportunities to thrive free from environmental hazards. This legislation will move us toward that goal.”

In July 2022, Rep, Grijalva introduced the Nogales Wastewater Improvement Act  with then Rep. Ann Kirkpatrick and Arizona Senators Kyrsten Sinema (D-AZ) and Mark Kelly (D-AZ). The bicameral legislation secured a historic agreement between the City of Nogales and the federal government that would have transferred the ownership, operations, and maintenance of the IOI to the U.S.-section of the IBWC.


Rep. Grijalva has worked since 2004 to secure funding for the Nogales Wash / Chula Vista and International Outflow Interceptor projects through the appropriations process. He requested $10 million for the project in fiscal year 2009 and $19.7 million in fiscal years 2010 and 2011. His Border Infrastructure and Jobs Act, first introduced in 2011, included an additional authorization of appropriations to fix the IOI.

In 2016, Rep. Grijalva filed an amendment to the Water Resources Development Act to require the United States Section of the International Boundary and Water Commission to provide resources for the Nogales Sanitation Project.

In June 2019, Rep. Grijalva introduced the bipartisan and bicameral Nogales Wastewater Fairness Act with then Senator Martha McSally (R-AZ) which would ensure that the IBWC is responsible for the  much-needed infrastructure repairs and future maintenance of the IOI to prevent raw sewage from spilling into waterways.

In 2020, Rep. Grijalva passed an amendment to direct $4 million within the IBWC to clarify the responsibility for maintenance and operation of the IOI. In the prior year, the House passed H.R. 4373, the Department of State, Foreign Operations, and related agencies appropriations bill that included Rep. Grijalva’s amendment to clarify responsibility for the IOI. The amendment directed $4 million within the IBWC to clarify the responsibility and maintenance of the IOI in addition to, and separate from, the funds designated for long-needed repairs.

In 2022, as Chair of the House Natural Resource Committee, Rep. Grijalva negotiated the Nogales Wastewater Improvement Act into the Wildfire Response and Drought Resiliency Act which passed the House on July 29, 2022.  Action was not taken in the Senate.

Additionally in 2022, Rep. Grijalva announced $8.6 million in federal funding for the Ephraim Canyon Flood Project which will construct and develop a detention basin in Nogales, Arizona between I-19 and the Mariposa Port of Entry (POE),  in Santa Cruz County to protect vital infrastructure including the IOI. 

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