Wastewater Reuse in Mexico Valley: Atotonilco WWTP. Jorge Malfeito Director of R&D explained this presentation at the Festival dell Acqua celebrated in Italy in Oct 5th, 2015. “Innovaciones medioambientales de la Edar de Atotonilco”. Presentación de Jorge Malfeito, director de I+D en ACCIONA Agua en el marco del Festival dell Acqua en Milán (Italia) acciona.sa/SSMmg

1. Wastewater Reuse in Mexico
Valley: Atotonilco WWTP
Jorge J. Malfeito
R&D Director (Acciona Agua)
©2015 Acciona Agua S.A.U. Todos los derechos reservados.

2. © 2015 Acciona Agua S.A.U. All rights reserved.
Presentation Outline
Introduction.
Drivers.
Primary objectives.
Mexico City drainage system.
Mezquital (Tula) Valley.
Atotonilco plant key players.
Atotonilco WWTP key figures.
Design Flows.
Process Diagram.
Sludge production.
Conclusions.

3. Introduction: Water Balance in Mexico City
(B. Jiménez‐Cisneros, 2012)

4. Introduction: Atotonilco WWTP
Atotonilco Waste Water Treatment Plant (WWTP) is the
largest wastewater treatment plant built in a single
phase.
It will be the largest
sanitation project in
Mexico with significant
social, environment and
sustainable benefits.
It will benefit 700,000
people of the Mezquital
Valle.
60% of the waste water
from the Valley of Mexico
will be treated.

5. Drivers
The Valley of Mexico Basin has one of the country’s
lowest waste water treatment indices (6%),which
produces pollution and a serious water imbalance
in the basin.
Benefits
To treat more than 60% of the waste water
produced in the Valley of Mexico.
To irrigate with treated waste water more than
80 thousand hectares in the Tula Valley, thus
enhancing the region’s agricultural potential.
To restore the good condition sof the surface
water bodies and streams that receive waste
water.
To improve the sanitation conditions of over
300.000 people who live inirrigation zones.

6. Primary objectives
Protect the health of farm workers and their families.
Prevent the spread of pollution in the region.
Restore the Endhó dam and organically rid it of any
contaminants, facilitating advances in irrigation
technology.

7. Mexico City drainage system

8. Mezquital Valley
Mezquital Valley (also call Tula
Valley) is located at 60 km northeast
from the Metropolitan Zone of the
Mexico City in the Hidalgo State.
The wastewaters are used, without
any treatment in a massive way, for
forage crop irrigation.
Mexico City and the surrounding
urban area are supplied with 85.7
m3/s, and generate a wastewater
average caudal of 60 m3/s.
Are irrigated more than 85.000 has.

9. Atotonilco plant key players
Total investment estimated (at 2014 prices) 710 millions USD.
The construction of the wastewater treatment plant is
performed under the DBOT scheme (design, build, operate
and transfer) with a concession for operation.
Contract signed: January 7, 2010.
Winning consortium (ATVM):
• Promotora del Desarrollo de América Latina S.A. de
C.V.
• Controladora de Operaciones de Infraestructura,
S.A de C.V.
• Atlatec, S.A. de C.V.
• Acciona Agua S.A.U.
• Desarrollo y Construcciones Urbanas, S.A. de C.V.
• Green Gas Pioneer Crossing, L.L.C.

10. ACCIONA Agua, Key Figures 2014
© 2015 Acciona Agua S.A.U. All rights reserved.
Total population served (construction,
O&M and services): 50 million.
Worldwide leader in Reverse Osmosis
(RO) desalination. More than 75
desalination plants (2,5 million m3/day
of installed capacity).
Wastewater, treatment and Reuse
(more than 400 plants built).
More than 100 conventional plants
operating and 40 supply services.
Permanent offices

11. Atotonilco WWTP key figures
The average design flow is 35 m3/s with a maximum of
42m3/s in the rainy season.
However the maximum flow is up to 50m3/s.
The generated biogas will
be used in the plant for
thermal and electrical
energy.
The estimated generation
of electricity is 200
GWh/year.

12. Design Flows
DRY SEASON RAINING SEASON
TREATMENT LINE AVERAGE MAXIMUN AVERAGE MAXIMUM
Convencional Treat. 23.0 30.0 27.6 33.0
Chemical Treat. 12.0 12.0 14.4 17.0
TOTAL 35.0 42.0 42.0 50.0
TOTAL TREATMENT CAPACITY : 1.041 hm3/Year

13. Process Diagram
Secundary
Settling

14. Sludge production
The sludge comming from the pretreatmet is estimated in
100.178 Tn/year.
It will be use for sanitary filling.
The biosolids production from the sludge treatment line (at
28%) will be around 837.408 Tn/year (2.294 Tn/day).
The quality of the sluge is type C,
in agreement with the standard
NOM‐004‐SEMARNAT‐2002
(SEMARNAT, 2002).
It could be use in agricultural and
for soils recovery.

15. Conclusions
Provided the finished plant
meets each of its objectives,
the Valley of Mexico
population will be granted a
far better standard of living,
with its agricultural sector
having a far better chance of
growth.
By improving upon the region’s
overall service, coverage, and
inefficiencies, Mexico can begin to
move away from its long history of
water‐related hindrances.

16. © 2015 Acciona Agua S.A.U. All rights reserved.