Dirty Waters Could Get Even Dirtier With Warming
A warmer, wetter climate could also boost pollution from cities and farms draining into rivers, lakes and streams.
A warmer, wetter climate in the eastern United States could also boost pollution from cities and farms draining into rivers, lakes and streams, according to a new report, and federal rules may not be flexible enough to handle it.
Researchers at the Rand Corporation examined two watersheds-the Patuxent River in Maryland and the North Farm Creek tributary of the Illinois River-to explore how the EPA's water quality plans would hold up during the future uncertainty of climate change.
In both regions, the study found that EPA's proposed plans meet the agency's water quality goals in under current assumptions of the region's climate, but do not meet water quality goals under future scenarios.
"What we were doing was thinking about future vulnerabilities," said Jordan Fischbach, a report author and co-director of Rand's Center for Water and Climate Resilience. "How might the amount of pollution change in these different futures. All the states whose waters feed into the Chesapeake Bay, they've set ambitious targets, can you do that?"
The Maryland case looked at rules governing urban stormwater runoff from parking lots and city streets. The Chesapeake Bay ecosystem and its bounty of native oysters, crabs and fish species, is still struggling despite decades of work by states and local governments to control runoff.
The Illinois example looked at agricultural runoff from farms, which flows downstream and ends up in the Mississippi River. In fact, freshwater flows of the Mississippi carry an overabundance of nitrogen and phosphorous, primarily from farms, into the Gulf of Mexico. Each year, this runoff plume creates a so-called "dead zone" of oxygen-starved water that kills bottom-dwelling marine life.
Estimates by the International Panel on Climate Change (IPCC) and the National Climate Assessment call for a wetter and warmer eastern United States.
"The trend is wetter, but it ranges from drier to a whole lot wetter," said Robert Lempert, senior scientist and director of Rand's director of long-range policy and human condition.
"Whether its farmland or a parking lot, when you run it in a simulation model, you see that as you increase rainfall, you increase the pollutants deposited into a river or stream," Fischbach added.
This climate-juiced rainfall might double pollution levels by 2050, the researchers said.
Solutions include building more "green infrastructure" to treat runoff before it reaches the river. This includes things like using grass waterways to slow down runoff, leaving tillage from harvested crops on the ground so rainwater doesn't hit not bare soil and building parking lots with grass strips to help water soak into the ground.
EPA officials in Washington say they're working on the problem of polluted runoff now and planning for what could happen in a wetter world of the future. The agency approved a new rule in August that strengthens the definition of high quality water, a rule that has been fiercely opposed by farm groups and Republicans in Congress.
"Maintaining high water quality is critical to supporting economic and community growth and sustainability," said the EPA statement to Discovery News. "Protecting high water quality also provides a margin of safety that will afford the water body increased resilience to potential future stressors, including climate change."
Ongoing water shortages around the world, along with recent drought conditions in the western United States, have resulted in a flood of new research and proposals around water technology. We take a look at some concepts -- from simple to complex to rather ancient -- that are designed to help us collect, store, transport and even create water where it's needed most.
The severe drought in California -- now in its third year -- has triggered new interest in a relatively old technology. Desalination plants turn seawater into drinking water by way of high pressure valves and semi-permeable membranes. Traditionally an expensive and energy-intensive process, recent innovations have made desalination a more viable option. The city of Carlsbad, Calif., is set to open the biggest
in the Western Hemisphere later this year.
Desalination plants are efficient, relatively speaking, but they're not very pretty. A couple years back, IBM and Airlight Energy turned heads with their
(HCPVT) system, designed to generate solar power and desalinate water at the same time. The sunflower-shaped solar collectors use a liquid cooling system that could potentially double as a small-scale desalination plant, providing both energy and water for apartment buildings, hotels or hospitals.
Water recycling is the umbrella term for reuse and reclamation systems that involve treating wastewater and returning it to underground aquifers or reservoirs. Along with desalination, it's among the existing technologies being optimized for large-scale use. San Diego's
project, for example, treats wastewater with three different techniques -- membrane filtration, reverse osmosis, and ultraviolet disinfection -- before piping the recycled water back into reservoirs.
One nice thing is that water generating systems tend to scale down nicely. This
water-harvesting billboard in Lima, Peru, uses dehumidifiers to pull moisture out of the atmosphere. Then a drip irrigation system waters the adjacent garden, producing more than 2.500 heads of lettuce per week. The billboard was built by -- and advertises -- Lima's University of Engineering and Technology.
The Air Orchard is just one of several clever self-advertising projects the university has built to advocate engineering solutions to environmental issues. This
also pulls moisture from the air -- Lima's average humidity is around 80 percent year-round -- and turns it into drinkable water provided by a dispenser at the base.
Lima is the kind of town that doesn't mess around. As the second largest desert city in the world (behind Cairo), it has faced water problems for centuries. A new initiative by the city's water utility plans to
to bring water down from rivers in the Andes. It's something of a fixer-upper project: The canals were built by pre-Incan civilizations between 500 and 1,000 AD.
The concept of harvesting water with fog nets has been around a long time and some ambitious large-scale projects have been tested across the globe, most notably in
. A few years back, German design student Imke Hoehler proposed a design for portable and collapsible tent-like fog nets that could potentially harvest up to 20 liters of water per day under the right conditions.
Then there are the research projects that get
In March, a team of Japanese scientists proposed studying the microscopic workings of certain moisture-gathering plants to design the next generation of water collection systems. Electron microscope imagery reveals that such plants use cone shaped hairs to catch and store water, then change shape release the moisture in dry conditions. The team hopes advanced fiber technology could essentially replicate the process.
Global droughts and water shortages can seem like terrifying, insurmountable problems. But fear not. As with so many things in this world, William Shatner has our back. The actor and
recently proposed a plan to pipe water from the Pacific Northwest to arid sections of California by way of -- well, the details are
. But long-distance water pipelines have a
in the U.S. and several new projects are in various stages of proposal. And let it never be said that Shatner doesn't follow through: He recently launched the
website, dedicated to exploring the issue.
Designed and built by the Washington-based engineering firm, Janicki Bioenergy, the very official-sounding Omniprocessor S100 uses heat from sludge to make water. A trial run is underway in Dakar, Senegal, where the machine -- which has received funding from the Bill and Melinda Gates Foundation -- is processing sewage from a community of about 100,000 people. The sewage is first heated intensely to dry it and then during the process, the water vapor is captured, heavily processed and turned into drinking water.