A consortium including the French company Degrémont, Sumitomo Corporation of Japan and Prodin, a group of local civil engineering firms, signed a build, operate and transfer (BOT) contract with the city of San Luis Potosi in Mexico for a wastewater treatment plant that will recycle 80,000 m3/day of the city's wastewater for industrial and agricultural purposes. Construction will take two years and Degrémont will run the plant for 18 years.
The g263-million contract is the sixth contract of this type that Degrémont has won in Mexico. The water reuse technologies planned for the facility will enable the province to conserve water resources while meeting the industrial and agricultural needs of a dryland area where groundwater quality has seriously deteriorated.
The Mexican government encourages private investment and promotes the development of infrastructure and capital equipment for environment protection. Under this policy, a government subsidy will cover 30% of construction costs.
The facility is designed to channel 57% of the water after primary treatment to a lagoon before distributing it to farmers for whom the nutrient-rich water is valuable. The remaining 43% goes through secondary and tertiary treatment for use as coolant fluid in the nearby thermal power station at Villa de Reyes.
Mexico has been encouraging water reuse for many years. Degrémont has built and runs 11 facilities in Mexico; seven use a technology producing water fit for agricultural reuse and four produce water for industrial reuse.
