Chapultepec WWTPReuse and aquifer recharge project for sustainable management of water resources in Mexico City

ISMAR 9June 2016

Alejandro Zuluaga

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 20161 I

Summary

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 20162 I

• Context: Water resources in Mexico City

• Chapultepec WWTP project• Objectives: Reuse and Aquifer Recharge• Water treatment Line• Technologies• Guarantees

• Aquifer recharge• Polishing treatment• Treatment line• Guarantees

• Conclusions

Context: Water resources in Mexico City

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 20163 I

Context: Water resources in Mexico City

High percentage of the population and part of the economy of the region depends on the water resource

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 20164 I

Pressure on water resources on the Valley of Mexico was estimated at 136% in 2013 and 138% in 2014

Actual overexploitation of groundwater resources in the Valley of Mexico is estimated at 23 m3/s

Actual overexploitation of the aquifer of the metropolitan area of Mexico city is estimated at 3,5 m3/s

Around 75% of the 20 million inhabitants of the metropolitan area of Mexico city depend on groundwater resources

Around 11 m3/s in the Valley of Mexico are used for agriculture

Chapultepec Wastewater Treatment Plant (WWTP)

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 20165 I

Chapultepec WWTP project: Objectives

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 20166 I

Increase water reuse in order to reduce water scarcity and preserve the forest of Chapultepec Satisfy water needs of the forest of Chapultepec (lakes of Chapultepec

and irrigation of the forest) Aquifer recharge

Improve water quality of the lakes

Improve water infrastructure

Chapultepec WWTP: General scheme

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 20167 I

Chapultepec WWTP

Chapultepec LakesWastewater 2 Polishing

WTP

Irrigation Chapultepec

forest

Aquifer recharge (2x2 injection wells)

Chapultepec WWTP: Location

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 20168 I

Chapultepec WWTP

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 20169 I

Chapultepec WWTP: Treatment line

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201610 I

Pretreatment Biological reactor

Membrane Biological Reactor

Wastewater

UV Disinfection

Sludge Chapultepec Lakes

Chapultepec WWTP: Features

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201611 I

Carbonaceous and nutrient removal (N&P)

Odor treatment

Reduced footprint (no need of clarifier and sand filtration)

Excellent treated water quality (0,035 microns membrane cut off)

UV disinfection → No disinfection byproducts

Chapultepec WWTP: Ultrafor™ technology

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201612 I

Chapultepec WWTP: Ultrafor™ technology

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201613 I

Physical barrier → constant water quality

0,035 microns membrane cut off Total removal of pollens, Yeasts

bacteria and smallest microorganism

Removal of most colloids, viruses and macro-organic molecules

Guarantee of sanitation

Small footprint

Automated operation

Chapultepec WWTP: Treated water guarantees

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201614 I

Parameters Process Guarantees

COD < 50 mg/l

BOD5 < 20 mg/l

TSS < 20 mg/l

N tot < 8,5 mg/l

P tot < 2 mg/l

Total coliforms < 240 / 100 ml

Fecal coliforms < 240 /100 ml

Aquifer recharge

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201615 I

Polishing treatment: 2 Water Treatment Plants

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201616 I

Polishing treatment: Treatment line

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201617 I

Pretreatment Ultrafiltration Membranes

Reverse Osmosis

Lakes

UV Disinfection

Injection wells

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201618 I

Polishing treatment: Features

UF filtration for suspended solids and microorganisms removal

Reverse Osmosis for removal of organic compounds, pesticides and other components

UV disinfection to avoid any disinfection byproduct

Polishing treatment: Treatment capacity

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201619 I

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201620 I

Polishing treatment: Guarantees

Comply with NOM 014 - Requirements for artificial aquifer recharge with treated waste water

Total removal or inactivation of pathogen microorganisms

Comply with NOM 127, Drinking water parameters

TOC ≤ 1 mg/l

Conclusions

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201621 I

Conclusions

Chapultepec WWTP: Reuse and Aquifer Recharge - ISMAR 9 - June 201622 I

Reuse and aquifer recharge are a solution for the water scarcity problem of the Valley of Mexico and the Metropolitan Area of Mexico City

Chapultepec WWTP is an example to follow for the sustainable management of the water resource

The technologies used allow to comply with the water quality requirements needed for a direct recharge of the aquifer and the stringent footprint requirements of the proyect