Lakes Around the World Are Losing Water Far Faster Than Predicted

News Analysis

A new study of the health of over 2,000 lakes published by scientists from the University of Colorado in Boulder showed the health of the world’s lakes is in big trouble.

According to the report, a full 53% of all these bodies of water have registered “statistically significant declines” in their water levels during the period between 1992 and 2020. Collectively they lost roughly 22 gigatons of freshwater every year since at least 1992.

To put that number in perspective, the scientists noted those annual water losses were equivalent to 100% of all water use in the United States just seven years ago, in 2015. They also calculated this average loss as equivalent to 17 times the entire capacity of Lake Mead, the largest man-made water reservoir in U.S. Lake Mead and the Colorado River is a critical water supply backup for over 40 million in seven western and southwestern states and Mexico.

What was left behind is also more clouded with sedimentation, silt, and pollution from agricultural runoff, rendering less and less of it usable for the many ways the world depends on it. Combined with the net losses, the message is an alarm bell which must be listened to now, rather than just press the snooze button on it the way we have on so many other warnings in the 21^st century.

Lakes hold 87% of all the freshwater on the surface of the planet. Ice, snow, and glaciers in colder regions form the rest. That freshwater is critical first and foremost for the aquatic life which lives within it, but also as the source of water which keeps plants, forests, and all other forms of life — including us — alive. It is distributed through rivers, streams, land runoff, in aquifers residing not far below the surface, and via hydrological cycles of rain as it evaporates into the atmosphere and eventually falls back to ground again.

The water is used by us directly for drinking, cleaning, and sanitation. It powers our global hydroelectric facilities. It cools other forms of power generators and many other industrial processes, carrying the excess heat away and back out. It irrigates farmlands and tree orchards. It supports vast and global eco-systems and food chains. It supports inland shipping in many nations. As part of the carbon discharge cycle, it is also critical for the many bio-geochemical processes which recycle nutrients and absorb some carbon.

When that freshwater is lost, even if the lakes are not totally drained, the impact can be staggering. Hydroelectric power levels in Ethiopia and China, for example, were severely impacted by recent sharp declines in flow rates of the Nile River in Africa and in the regions which eventually flow down to the Mekong Delta in Asia. Crop failures in areas as diverse as southern Chile, the western United States, most of western Europe, and northern India are a direct result of drought in those regions and the lack of sufficient water reserves to recover from the losses. In Spain, for example, reservoirs in northeastern Catalonia, the same province where Barcelona is located, have fallen from a mean 58% of total capacity in 2022 to just 26% now.

The data for the study was gathered primarily via the most exhaustive review yet of satellite data and related climate models on what is happening to over 2,000 large lakes throughout the globe. They also made use of recently developed algorithms which help compensate for the time-varying nature of what was observed directly by satellites such as Landsat, for which they studied a total of 248,649 images, CryoSat-2, ENVISAT, ICESat, ICESat-2, Jason series 1-3, SARAL, and Sentinel 3. To ensure they were not just picking up spot data, they also sampled at rates of roughly six times every year for every region.

To help understand root causes for why individual lakes are drying up, the researchers carefully studied the building and use of new reservoirs and hydroelectric facilities, and the impact of their use on immediate changes in specific lake metrics.

Their analysis showed that 53% of the world’s largest lakes, with a margin of error of plus or minus 2%, were losing water by substantial amounts each year. The total loss was 21.51 gigatons per year, with a margin of error of plus or minus 2.54 gigatons per year.

That loss, they concluded, “prevails across major global regions including western Central Asia, the Middle East, western India, eastern China, northern and eastern Europe, Oceania, the conterminous United States, northern Canada, southern Africa, and most of South America.”

The biggest single drop in water volume in the world was logged in the Caspian Sea. Its water losses contributed to just under half of the total water losses of all lakes added together during the 1992-2020 period the study analyzed. The loss of freshwater in this lake has been so dramatic that it is also quickly being compromised by oceanic salt water creeping in via underground sources and small streams, destroying the lake eco-system that so many species depended upon.

Of those declines, the scientists note that 56 ± 9% is directly attributable to human activity and “potential evapo-transpiration (PET)” — also known as evaporative demand increases — tied to the climate crisis.

How these causes impact varies by region, but the main causes are widespread. As the study explains further:

“Unsustainable water consumption dominates the observed drying of the Aral Sea (−6.59 ± 0.36 Gt/year) in Central Asia, Lake Mar Chiquita (−0.75 ± 0.09 Gt/year) in Argentina, the Dead Sea (−0.63 ± 0.04 Gt/year) in the Middle East, and the Salton Sea (−0.11 ± 0.01 Gt/year) in California.”

“Increasing temperature and PET [byproducts of the climate crisis] led to the complete disappearance of Lake Good-e-Zareh (−0.48 ± 0.17 Gt/year) in Afghanistan, Toshka lakes (−0.13 ± 0.10 Gt/year) in Egypt, and marked drying of Lake Kara-Bogaz-Gol (−1.27 ± 0.09 Gt/year) in Turkmenistan, Lake Khyargas (−0.35 ± 0.03 Gt/year) in Mongolia, and Lake Zonag (−0.26 ± 0.14 Gt/year) in China;” and

Changes in rainfall and associated runoff were primarily behind rapid declines in “the Caspian Sea (−18.80 ± 0.93 Gt/year), Lake Urmia (−1.05 ± 0.06 Gt/year) in Iran, the Great Salt Lake (−0.29 ± 0.08 Gt/year) in the United States, Lake Poyang (−0.13 ± 0.12 Gt/year) in China, Lake Titicaca (−0.12 ± 0.08 Gt/year) on the border of Bolivia and Peru”.

24% of the remaining lakes did in fact experience a net water gain. But since much of that was due to hydroelectric dam building sites, or in remote areas such as the Inner Tibetan Plateau where glacial melt is happening, this is less a net gain for the planet than a rearrangement of the existing planetary water reserves.

Collectively, this accelerated decline in the total amount of freshwater available from the world’s lakes represents another warning that humanity is overusing its precious water resources at a dangerous rate.

As lead study author Fangfang Yao said in a comment about this important research, the results of the study “helps us understand human alteration of the water cycle and also helps identify management solution.”

The full study on the loss of water in freshwater lakes, “Satellites reveal widespread decline in global lake water storage,” by Fanfang Yao, et. al., was published in the May 18, 2023, issue of Science.

However, the study didn't really go far enough and suggest the obvious — that we must change our relationship to water, how we think about it and utilize it. It is perfectly feasible for humans to continually recycle water and doing so makes a huge difference, not just in water conservation but in utilizing and recycling the nutrients. This is now being proven and it changes the equation for humanity and planet Earth.

In a lab in Mexico, Climate Survival Solutions, Inc. is currently testing its first prototype of what it calls the PolyBio System, which recycles waste water and produces energy, nutrients, food and pure water in an 8 stage circular system that uses natural biological processes.

1. Toilet water is first processed in an anaerobic digester which breaks down organic matter, unlocks nutrients and produces methane. This process uses hundreds of different kinds of microbes and breaks down most all chemical contaminants. Unlike conventional digesters, the PolyBio System uses a linear digester that kind of extends the human digestive tract. This increases efficiency by supporting zones of specific types of microbes for each stage of the digesting process, instead of mixing them all up and forcing them to compete with each other.

The waste from a single adult can produce up to 17 liters of methane gas. The indigestible bio-solids removed from the system every few months can be used to grow mushrooms or to improve soil.

2. The methane is used for energy and if burned, the CO2 recycled back into the system to accelerate algae and plant growth. It can also be purified and the extracted hydrogen used in a fuel cell. 

3. After passing through the anaerobic digester the water flows into an aerobic digester where it is oxygenated and meets up with greywater and organic matter is further reduced and more nutrients released. Any potentially harmful microbes are eliminated at this stage. The water is filtered, sterilized with UV light and revitalized in a vortex before going to the next stage. 

4. The nutrient rich water then flows to algae or aquatic plant growing tanks. Algae can be used for bio-fuels, plastics, paper, textiles, nutraceuticals, food, or raw material for other applications. Some aquatic plants are highly nutritious, such as the smallest flowering plant, Wolffia globosa, a type of duckweed that is a super-food that has a better protein profile than any other food, various vitamins, including D and the elusive B-12, omega 3s and many essential minerals. Wolffia is also one of the fastest growing plants on Earth and can double its mass every 2 days.

If the water is polluted with chemicals or heavy metals, those are removed at this stage by the algae and/or plants.

5. After feeding algae and/or aquatic plants and being purified, the water loses some of its nutrients so it next flows into a pond-like eco-system with diverse species where light is converted back into various nutrients through biological processes. Here, fish can be fed with the algae or plants produced by previous and subsequent stages. The water is again revitalized in vortex before going to the next stage.

6. The nutrient restored water then supports food crops via hydroponic, aquaponic and aeroponic type systems.

7. Plant and food scraps are fed to worms and the worm castings used as fertilizer as needed. 

8. The water is filtered down to 5 microns then enters a dark settling tank where any biological activity ceases and the water is then filtered again, revitalized in a vortex and fed back into the system for domestic water use. At this stage it is far more pure than most any municipal tap water and doesn't need to be treated with any potentially harmful chemicals. If desired, drinking and cooking water can be further purified through reverse osmosis, but it isn't necessary. 

With the PolyBio System, water and nutrients can be recycled onsite indefinitely while producing energy and an abundance of food. This massively reduces human water consumption, eliminates the negative impacts of conventional wastewater treatment methods, prevents the formation of dead zones in the oceans, massively reduces the energy and land required for food production and distribution, eliminates food waste that ends up in landfills and provides food and water security.

The challenges to implementation are significant, but not insurmountable.

• Regulatory - At present, regulatory authorities do not allow much in the way of water re-use due to health concerns, lack of awareness and lack of public support. 
• Infrastructure - Existing wastewater and water infrastructure is not designed to support extensive water recycling and retrofitting would be costly.
• Public Acceptance - While many people are already drinking water that once flowed through a toilet, they may not be aware of it and would oppose the idea of water re-use no matter how pure the water is.

The best approach to these obstacles to implementation would be to construct new communities that utilize the PolyBio System and are climate-proof, carbon-neutral, self-sufficient and truly sustainable in areas with progressive local government. 

With an estimated 1 billion climate refugees by the end of the century, now is a good time to design and build intelligent communities that don't have a negative impact on the Earth and which enable humanity to lead healthy and satisfying lives in peace.

The first such community, Tataouine Community and Research Center, is under initial construction in Arizona but is being held back by local authorities. It is hoped that the PolyBio System can be approved at the state level.