MEXICO CITY METROPOLITAN AREA: THE LARGEST MEGACITY IN AN UNSUSTAINABLE PATH CECILIA TORTAJADA THIRD WORLD CENTRE FOR WATER MANAGEMENT, MEXICO

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1 MEXICO CITY METROPOLITAN AREA: THE LARGEST MEGACITY IN AN UNSUSTAINABLE PATH CECILIA TORTAJADA THIRD WORLD CENTRE FOR WATER MANAGEMENT, MEXICO

2 Metropolitan Area of Mexico City Area of 4,925 km 2 1,484 km 2 in Mexico City 3,441 km 2 in State of Mexico 0.3% of land and 22-25% of population 16 boroughs of Mexico City 34 municipalities of State of Mexico 45% of commercial, services and industrial activities 32% of the GDP

3 Population density, Metropolitan Area of Mexico City N State of Mexico Density population 13,065 17,718 people km -2 Federal District 7,597 13,064 people km -2 3,857 7,596 people km -2 2,091 3,856 people km ,990 people km -2 Federal District Boundary Municipality Boundary Population growth Water demands 30, thousand 20,000 10,000 m 3 day year year

4 Water needs, Metropolitan Area of Mexico City 9 million people in Mexico City (95.3% have access to water) 14 million in State of Mexico (84.2% have access to water) 364 l/person/day in Mexico City 230 l/person/day in State of Mexico 290 l/person/day (including industries, services, unauthorized uses and leakages of 30-40%)

5 Sources for drinking water for the Metropolitan Area (m 3 /s) Mexico City State of Mexico Total % INTERNAL SOURCES Wells Rivers and springs EXTERNAL SOURCES Cutzamala Lerma TOTAL 34.8 (52.7%) 31.2 (47.3%) Source: DGCOH, 1997; CAEM, 2002.

6 Groundwater abstraction from the aquifer Abstraction of m 3 /s Natural recharge rate - 20 m 3 /s Overexplotation m 3 /s Lowering of the water table and land subsidence at the rate of cm/year in some parts of the city

7 External sources of water Lerma River m 3 /s m 3 /s 6 m 3 /s Cutzamala System m 3 /s m 3 /s m 3 /s $ 23 million/m m 3 /s Water has to be transferred from more than 150 km away, pumped to a height of more than 1000 m. It requires 102 pumping stations, 17 tunnels and 8 km of canals, becoming a very energy-expensive operation

8 Tuxpan Dam El Bosque Dam Zitácuaro City Ixtapan del Oro Dam Water Treatment Plant Chilesdo Dam Colorines Dam Villa Victoria Dam Sta. Isabel Tank Stabilization Pond Donato Guerra Valle de Bravo Dam Temascaltepec River Toluca City Emiliano Zapata Tank Pericos Tank Tank No. 3 Barrientos Tank Mexico City Teuhtli Tank Coacalco Tank Cerro Gordo Tank La Caldera Tank El Tule Dam 2800 De las Cruces Mountains 2600 P.P. 6 Elevation (msl) Chilesdo Dam, P.P. 5 P.P. 4 P.P. 3 Valle de Bravo Dam, P.P. 2 Villa Victoria Dam Water Treatment Plant Dam Pumping plant (P.P.) Piezometric line 1600 Colorines Dam, P.P. 1 Source: Tortajada, 2003.

9 Cutzamala System - Cost Only the construction of Cutzalama system ($1300 million) was higher than the national investment in the entire public sector in Mexico in 1996, including: education ($700 million) health and social security ($400 million) agriculture, livestock and rural development ($105 million) tourism ($50 million) and marine sector ($60 million). Source: CNA, 1997.

10 Infrastructure for water distribution, State of Mexico, ,259 l/s are distributed to 10 municipalities of the metropolitan area 60.8 km (42%) out of km have been constructed

11 Land subsidence in the Federal District Period cm 100 cm 150 cm 200 cm 250 cm : 3-5 cm/year : 16 cm/year : 35 cm/year 1954 NO EXTRACTION FROM WELLS IN THE MEXICO CITY SUB-BASIN Period FROM cm/year 10 cm 20 cm 30 cm 40 cm Source: INEGI, 2004.

12 Abstraction of water (m 3 )/subsidence in Mexico City Damages to the infrastructures for water supply and sewerage systems Construction of costly pumping systems to remove rainwater and wastewater from the City Degradation of groundwater quality Source: Lesser & Cortés, 1998.

13 Subsidence in Mexico City City centre, 10 cm Airport, cm Source: Mazari-Hiriart et al., 2001.

14 Problems... Flooding Difference in levels between some parts of the City and the collectors Inability of the overall system to pump all the water out of the City in rainy season Due to the subsidence of the City, downtown is 7 m below the highest point of the Grand Canal, which makes it difficult for the water to be pumped out of the area

15 Pollution of groundwater Problems... Faecal coliforms Bacterias such as Aeromonas, Pseudomonas, Staphylococcus and Vibrio in the southern and eastern part of the City Helicobacter pylory, related to ulcers and stomach cancer in the aquifer in the area of Xochimilco and in water of Cutzamala before being treated.

16 Volumes of water abstracted in Mexico City (million m 3 /year) Agriculture Agroindustry Rural 500 Aquaculture 400 Services Industrial 300 Livestock Urban Multiple Energy 0 Surface water Groundwater Comercial activities Source: CNA, 2004.

17 Volumes of water abstracted in State of Mexico (million m 3 /year) 2,000 1,800 Agriculture 1,600 Agroindustry 1,400 1,200 1, Rural Aquaculture Services Industrial Livestock Urban 400 Multiple 200 Energy 0 Surface water Groundwater Comercial activities Source: CNA, 2004.

18 Total volume of water abstracted (million m 3 /year) and number of concessions USE MEXICO CITY STATE OF MEXICO CONCESSIONS VOLUME ABSTRACTED CONCESSIONS VOLUME ABSTRACTED AGRICULTURE , AGROINDUSTRY DOMESTIC (one user) AQUACULTURE SERVICES INDUSTRIAL LIVESTOCK URBAN 1 1, ,865 1,157 MULTIPLE ENERGY ,998.9 COMMERCIAL ACTIVITIES Source: CNA, 2004.

19 Total volume of water abstracted (million m 3 /year) and number of concessions USE MEXICO CITY STATE OF MEXICO CONCESSIONS VOLUME ABSTRACTED CONCESSIONS VOLUME ABSTRACTED AGRICULTURE , AGROINDUSTRY DOMESTIC (one user) AQUACULTURE SERVICES INDUSTRIAL LIVESTOCK URBAN 1 1, ,865 1,157 MULTIPLE ENERGY ,998.9 COMMERCIAL ACTIVITIES Source: CNA, 2004.

20 Total volume of water abstracted (million m 3 /year) and number of concessions USE MEXICO CITY STATE OF MEXICO CONCESSIONS VOLUME ABSTRACTED CONCESSIONS VOLUME ABSTRACTED AGRICULTURE , AGROINDUSTRY DOMESTIC (one user) AQUACULTURE SERVICES INDUSTRIAL LIVESTOCK URBAN 1 1, ,865 1,157 MULTIPLE ENERGY ,998.9 COMMERCIAL ACTIVITIES Source: CNA, 2004.

21 Total volume of water abstracted (million m 3 /year) and number of concessions USE MEXICO CITY STATE OF MEXICO CONCESSIONS VOLUME ABSTRACTED CONCESSIONS VOLUME ABSTRACTED AGRICULTURE , AGROINDUSTRY DOMESTIC (one user) AQUACULTURE SERVICES INDUSTRIAL LIVESTOCK URBAN 1 1, ,865 1,157 MULTIPLE ENERGY ,998.9 COMMERCIAL ACTIVITIES Source: CNA, 2004.

22 Total volume of wastewater discharged (million m 3 /year) and number of concessions USE MEXICO CITY STATE OF MEXICO CONCESSIONS VOLUME DISCHARGED CONCESSIONS VOLUME DISCHARGED AGRICULTURE AGROINDUSTRY DOMESTIC (one user) AQUACULTURE SERVICES INDUSTRIAL LIVESTOCK URBAN MULTIPLE ENERGY COMMERCIAL ACTIVITIES TOTAL Source: CNA, 2004.

23 Wastewater discharges (m 3 /s) USE MEXICO CITY STATE OF MEXICO CONCESSIONS VOLUME DISCHARGED CONCESSIONS VOLUME DISCHARGED TOTAL m 3 /s m 3 /s m 3 /s m 3 /s Irrigation of 90,000 ha in the Mezquital Valley

24 Subsidence in D.F. and Infrastructure problems 1910 Mexico City Gravity Sewage System Tequisquiac Tunnel 2 6 Grand Canal Slope 19 cm/km Pumping Sewage System Slope 12 cm/km Pumping Sewage System Slope 10 cm/km Pumping Sewage System Federal District Slope 0 Interceptors Central Deep Drainage Source: National Research Council, 1995.

25 Water Management Constraints Old infrastructure Over-explotation of the aquifer (land subsidence) Dependence on water supply from outside sources About 30-40% of water is lost from the distribution networks due to leakages which could provide water to 4 million people Metering is almost non-existent (flat rates) Only about 18-20% of users pay their water bills Institutional arrangements

26 STRATEGY FOR WATER MANAGEMENT FOR MEXICO CITY, 1992 Water supply Financial self-sufficiency Metered service Programme on leakages detection

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28 PRIVATE SECTOR COMPANIES, 1994 Zone COMPANY PARTNERS AREAS NUMBER OF CONNECTIONS A SAPSA ICA CIE. Generale des eux Banamex B IASA Brittingham Severn Trent C TECSA Bufete Ind. Lyonnaise Bancomer D AGUAMEX Gutza Northwest water Gustavo A. Madero Azcapotzalco Cuauthemoc Benito Juarez, Coyoacan, Iztacalco and Venustiano Carranza Iztapalapa, Tlahuac, Xochimilco and Milpa Alta Tlalpan, Magdalena Contreras, Alvaro Obregon, Cuajimalpa and Miguel Hidalgo 298, , , ,789 Source: CADF, 1994.

29 ACTIVITIES 1. SERVICE TO CLIENTS: METERS, READING, DISTRIBUTION OF BILLS, COLLECTION OF FEES, INFORMATION OFFICES. 2. HUMAN RESOURCES AND SYSTEMS (QUALITY CONTROL). 3. TECHNICAL SERVICES: STATISTICS OF USERS AND NETWORKS, REPLACEMENT OF METERS. 4. OPERATIONS: MAINTENANCE OF METERS AND PIPES (LEAK DETECTION AND REPAIR).

30 RESULTS UPDATE LIST OF USERS AND CONNECTIONS COMPUTARIZED SYSTEM (USERS, CONNECTIONS, METERS INSTALLED, CONSUMPTION, BILLS, COLLECTION OF FEES, DEBTS). PROGRAMME ON LEAKES DETECTION. NO EXCEMPTIONS (EDUCATION AND HEALTH SECTOR). DISCOUNTS: RETIRED PESONNEL HAS ONE-YEAR RENEWABLE DISCOUNTS. PEOPLE FROM DISTANT PLACES WITH NO REGULAR SERVICE.

31 METERS FOR DRINKING WATER, D.F., METERS (THOUSANDS) TOTAL TYPE A* TYPE B TOTAL *METER A, CHEAPER. INSTALLED IN AREAS WHERE THE ECONOMIC RETURN WAS NOT ASSURED.

32 Efficiency indicators for drinking water management in Mexico City VOLUME OF DELIVERED WATER (MILLION OF m 3 ) USERS WITH BILL (THOUSANDS) 1, , , , , ,769.1 NO. OF BILLS FOR METERED SERVICE (THOUSANDS) , , , , ,582.7 CHARGED WATER (BILLION PESOS) BILLED WATER (BILLION PESOS)

33 WATER TARIFFS FOR FEDERAL DISTRICT, 2004 (dollars / m 3 ) Lowest limits m 3 /2 months Highest limit m 3 /2 months beyond Minimum payment

34 PRICES FOR DOMESTIC USE IN STATE OF MEXICO (PESOS/M 3 /BYMONTLY) GROUP A GROUP B GROUP A Group B WITH METER (0 to 25m 3) WITH METER (0 to 25m 3) WITHOUT METER WITHOUT METER Source: CAEM, 2002; : Ley de Hacienda del Estado de México; : Código Financiero del Estado de México y Municipios.

35 Metropolitan Area of Mexico City Munich 290 l/person/day 128 l/person/day 25 million people 1.4 million customers 48 m 3 /s wastewater m 3 /s rain 6.5 m 3 /s wastewater 15 m 3 /s rain 6% water treated 100% water treated 0.16 EUR 1,22 EUR

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