Iztapalala, Mexico City

Where is iztapalala

South east of Mexico City’s central business district

How does the topography and drainage affect water availability in Iztapalala, Mexico City

• Mile high mountain rimmed drainage basin (valley of Mexico)

• Very few permanent rivers into the valley

• Groundwater is the main source of water

• Built on land by draining and filling the old lake

How does climate affect water availability in Iztapalala, Mexico city

• Subtropical highland

• Temperatures vary 64C annually

• Lake basin with no outlets → flood and drought

• Precipitation from May to October

• Iztapalala receives 720mm of rainfall per year (less than Mexico City)

How does geology and vegetation affect water availability in Iztapalala, Mexico City

• Ring of pourus rock forms aquifers underneath

• Mountains topped with pine and oak forests → cleared as city expands onto foothills

Economic impacts

• Water deliveries = 10% of income per household

• Have to buy bottled water

• Rich can install rainwater harvesting ($1000)

Social impacts

• Lifestyle adaptations

  → ½ bucket of water to wash and shower

  → can’t flush the toilet

• Higher income areas can access tap water

• Lower income areas have to buy bottled water or have water delivered- costs 10% of household income and takes days for only 2000L to arrive

• Have to rely on bottled water

Environment impacts

• Severe shortages

• Regular flooding

• Leaks from ground sinking → subsidence = pipes pressured

  → corroding pipes

  → 40% of water lost through broken pipes

• Back up reservoirs depleted

• Aquifer is over exploited

Managing water supply

• Lerma river transfer

• Cutzamla system

• Water deliveries

• Bottled water

• Deep aquifer abstraction

• Rainwater harvesting

Lerma river transfer

• 6%

• Completed mid 1900 but is largely dry now

Cutzamla system

• 18%

• 1970-1994

• 11 boroughs → over exploited mazahaa Indians→ lack of river access

Water deliveries

• Very expensive and takes 5 days to deliver

• Inefficient and customers not satisfied

• 1000 trucks can only provide water for 2 million people → not enough water

Bottled water

• 127 gallons used per person per year

• 4x the average American

Deeper aquifer abstraction

• Drawing water from mile deep aquifers → $40m to pump and treat → supplies some of the city for 100 years

Rainwater harvesting

• Installing pipes and collection storage systems

• $1000 per house → only the rich can afford

• Only benefits high rainfall areas

How is demand being managed

Education

• Programme planned to educate children that water is valuable and needs to be used wisely.