Chihuahua, Chihuahua, Mexico

Rehabilitation and Upgrade of the North and South Wastewater Treatment Plants in Chihuahua, Chihuahua

Status: Completed


The North and South WWTPs began operations in 1995 and 2006, respectively. Both plants operate with similar processes consisting of preliminary, primary and secondary treatment in activated sludge bioreactors and clarifiers, with disinfection systems that use chlorine gas. The effluent from both plants currently complies with Mexican standards for water reuse and discharge to natural water bodies. The activated sludge from both plants is treated at the South WWTP, which has a sludge conditioning and treatment process and produces approximately 85,932 yards3/year of dehydrated sludge for use as fertilizer by local farmers. Biogas generated from the sludge digestion process is currently captured, stored and flared on site.


The project consists of rehabilitating and upgrading the North and South WWTPs, as well as designing, installing and operating a cogeneration facility in the South WWTP.


The main objectives of the Project are to continue providing adequate and sustainable wastewater treatment services in compliance with environmental and reuse requirements and to produce electricity through cogeneration to reduce power consumption from conventional fossil fuel sources, which will help prevent the emission of greenhouse gas emissions. Specifically, the rehabilitated and upgraded WWTPs will improve effluent quality and provide treatment for a total of 2,375 liters per second (lps) or 54.2 million gallons a day (mgd) in compliance with federal standards, as well as produce 33% less sludge.

Project Financing

Total Project Cost US US$14.7 millionM
NADBank Funding US US$11.2M - NADBank Loan