Poor planning, low rates and insufficient investment are the causes of the water shortage in the Mexico valley metropolitan area. If authorities and national water authority Conagua fail to take action now, the world’s second largest urban agglomeration will simply dry up.
A total of 33,000 l/s of water is distributed in greater Mexico City every day to serve its estimated 22mn inhabitants. However, around 40% is lost due to the poor conditions of the city’s potable water network.
The situation is worsened by overuse and waste. According to Conagua, average water consumption per person should be around 150l/d. While in some areas in the valley people only get an average of 40l/d of water, in other locations citizens are using an average of 800l/d.
WHEN CHEAP IS EXPENSIVE
The reason for excessive consumption is the low rates being charged for water services. Mexico City water utility SACM charges users 2 pesos/l (US$0.15) which is definitely not enough to maintain the system. The figure is much lower than the 16 pesos that should be charged to cover costs and carry out necessary maintenance works.
Low rates may have a favorable financial impact on society in the short term, but they only lead to carelessness and overuse of hydrological resources.
At some point, authorities will have to face and resolve the problem. However, the longer they wait, the more expensive it will be.
Considering that the 16-peso/l rate would only cover maintenance works, SACM needs a much higher monetary input to carry out the necessary rehabilitation and expansion works on the city’s 12,000km network.
Only 2,100km of pipelines have been installed in the last few years, which means that more than 82% of the network is old and in need of maintenance or renewal.
And while authorities are aware of water losses due to damaged pipelines, they are also dealing with the problem of water theft, which is much harder to control as it requires the kind of supervision the utility cannot afford.
SUSTAINABILITY BEGINS AT HOME
Mexico City needs to implement changes in accordance with the three pillars of sustainability: environmental, social and financial.
Authorities and Conagua officials need to monitor and limit the use of Mexico valley’s water resources, or they will inevitably dry up. They also need to increase control over water pollution to prevent further environmental damage.
Conagua must also look at the numbers and draw up a strong strategic development plan, including a gradual increase in water rates over a period of time, and with support from international financial entities to cover the cost of carrying out works in a relatively short period of time.
Finally, authorities need to educate users in the responsible use of water. The government has launched a television campaign focused mainly towards children, but they also need to increase adult awareness. They are the people who currently use large amounts of water, especially in informal activities such as cooking and textile production.
SACM should also implement a water collection and storage system large enough to serve Mexico City’s increasing population and needs. Research groups are already working on initiatives to store rainwater, while also preventing floods.
Institutions such as the Instituto Politécnico Nacional (IPN) university have developed technologies to reduce the use of water in the industrial sector, including vertically built industrial wastewater treatment plants for the textile industry, among others.
Water reuse is another option research groups are looking into. In fact, IPN already uses treated wastewater to irrigate the large green areas on its campus. These areas help combat air pollution and contribute to the city’s wellbeing. Therefore, the initial additional cost turns into savings.
At the same time, SACM should start to take part in the city’s integrated urban planning, as natural disasters such as floods, earthquakes and land movements also damage water and sewage networks.
Authorities may argue that fixing the Mexico valley water problem is too expensive, but the cost increases every day and soon it will be too late to do anything at all.
Source: Eva Medalla, BNamericas.com [subscription site], 27 Oct 2009