Mexico - restoring a desert lifeline
The Rio Grande (known as the Rio Bravo in Mexico) is the fifth-longest river in North America. It stretches almost 3,200km from the mountains of Colorado to the sea at Brownsville, Texas. Its basin covers some 440,000sq km.
The Rio Conchos is one of the Rio Grande’s main tributaries. It provides almost all the river’s water from the point at which it joins, just upstream of Big Bend National Park. Flowing from the Sierra Madre mountain range, through the Northern Chihuahuan Desert, the Rio Conchos acts as a lifeline for millions of people and thousands of species of plants, birds, mammals, fish and reptiles that live in the basin. Because of the river’s importance, it has been at the cutting edge of development in water management in Mexico, and is a vital case study for both national and global policies.
Threats
Water in the Conchos basin, both surface and underground, is already over-allocated. Changes in land use resulting from farming development and flood control measures, along with increased demand for drinking water, have significantly altered the river’s flow, as well as its sediment load, channel, floodplain and surrounding habitats. Pollution is also a major issue, with only 20% of wastewater being treated before it is put into the river system.
Overexploitation and unsustainable use of natural resources, such as timber, soil and water, particularly in the river’s headwaters, have led to deforestation, erosion and desertification.
Shortages of water and a reduction in productivity of land due to soil erosion and degradation mean that both livestock and arable farming are suffering. People on the fringes of the area, who used to be able to grow enough food to sustain themselves and occasionally make a small profit, are now not able to do so.
This is diminishing quality of life and forcing people to migrate to urban areas and to the US.
In addition, the area is suffering a loss of biodiversity and other traditional livelihoods.
In a desert environment, water is key to life. The increased pressure and resultant water shortages are having a direct impact on the survival of some species, in both population sizes and their habitat.
In addition to this, economies of scale mean that larger tracts of land are being used for livestock grazing and cultivation, further degrading and fragmenting natural habitats.
Solutions
WWF is working to establish sustainable ways of managing water resources in the Rio Conchos, and to secure vital flows of water to both people and biodiversity in the wider Rio Grande basin.
We aim to establish an effective committee to manage the river’s water resources.
We want to make sure that necessary legislation, and institutions capable of enforcing that legislation, are in place. This will then ensure that the ecosystem gets the quality, quantity and distribution of water at the right times in order for it to flourish – its so-called ‘environmental flow’.
We are working to ensure decision makers don’t only consider the water that is visible and immediately available – the surface water found in rivers and lakes. There is a huge amount of water stored underground in aquifers (groundwater) and this is widely exploited by farmers and other users to supplement surface water. The two systems are strongly linked, each replenishing the other. Therefore they must be managed together, as decisions about the use of water from one will impact on the other.
In addition, we are ensuring that key sections of river and springs in the Conchos basin are protected to preserve biodiversity and act as river health indicators. We want to protect the rare and endemic species that live in them, such as the Julimes pupfish, which is found only at the Pandeño Spring and is thought to be the freshwater fish that lives in the hottest water. We are also supporting populations of numerous large mammals in the Chihuahuan Desert.
We also want to build awareness among water users in the Rio Conchos basin, including farmers, urban and rural domestic users, and the manufacturing industry, about the importance of water allocation for the environment.
Through this work, we will help to inform and develop water management practices in other areas of Mexico and the US.