Tamara Wilhite is a technical writer, industrial engineer, mother of two, and published sci-fi and horror author.
How Can We Prevent a Freshwater Crisis?
The freshwater crisis is a slow-moving disaster that we’ve seen coming for years. A growing population needs more fresh water. We’ve been meeting the growing need by pumping out groundwater, but we’re now pumping that out at a much faster rate than nature can replenish it. Desalinization works to some degree, but it is expensive. New technology is the only viable solution to the freshwater crisis.
Nano-materials are the future of desalinization. Traditional desalinization required massive amounts of energy, heating sea water to boiling temperatures, and then converting the salt-free steam to drinking water. Too many parts of the world in desperate need for drinking water, even if they have ocean access, cannot afford this. Filters that let water molecules pass while blocking salt exist, but they are equally energy-intensive. That is, until now.
In 2016, Lockheed Martin rolled out a new “nano-material”, an ultra-thin graphene membrane that can let water pass but blocks salt and other unwanted materials. The thinner the membrane, the less power is required to push water through the filter. If the new filter is 10% the thickness of traditional filters, you can either get ten times as much drinking water for the same investment of energy or reduce the energy expenditure to get the same amount of drinking water to a tenth of what it cost. Then you have more power for general users.
In reality, the filter is less than 1% the thickness of traditional water filters. This means that you could set up desalinization plants without having to have massive industrial grade power production to sustain it.
Interestingly, the improved filtration technology will lower the cost and accelerate the adoption of wastewater recycling, something we’ll address later in this article.
2. The Internet of Things
The internet of things refers to the connected grid of sensors and controls that wire every “thing” together. This networking is being rolled out in manufacturing plants and power grids. In manufacturing facilities, every motor, processor and major power consuming part reports is energy requirements and functional state. Mechanics can see which items are vibrating excessively, overheating or consuming too much power and repair it almost immediately. The industrial engineers gain masses of data they can mine and analyze, determining ideal maintenance schedules and production plans that maximize production while minimizing energy costs. In the power grid, the connectivity of the internet of things is necessary simply to maintain grid stability as we bring renewables into the grid. Locally produced power is routed to the nearest distribution points, and no one brings up backup power sources like natural gas turbines unless necessary.
This same technology is being used in the effort to better manage water and minimize its waste. In greenhouses and, increasingly, farm fields, atmospheric humidity, soil dampness and irrigation systems are all monitored. No one turns on the irrigation if the soil is sufficiently damp or it is about to rain. Irrigation is limited to the specific areas that need it. Masses of data are analyzed to determine improved irrigation system layouts so that you have less run-off and better coverage.
3. Recycling . . . of Water
Wastewater reuse is well established in irrigation, since this allows farmers to tap cheap water that most people don’t want to drink. Unfortunately, the sheer need for drinking water means we’re starting to look at water recycling, the conversion of wastewater into “reclaimed” water that goes back into the system.
The water crisis may be solved with reclaimed water. The “Toilet to Tap” movement solves many problems at once. By recycling local wastewater and re-distributing it, there is less need to bring in water from outside. That reduces the need to build more water pipelines or truck it into remote areas. In places like Perth, Australia, and San Antonio, Texas, wastewater recycling allows them to meet water demand without needing to build much more infrastructure. In Texas, building wastewater recycling has avoided the need to build yet more lakes to try to capture limited seasonal rainfall, something that often floods the limited supply of good farmland.
The wastewater is initially subjected to sedimentation, goes through multiple levels of filtration and reverse osmosis, and then it is treated chemically to meet or exceed the water quality standards that water from the local river had to meet.
By recycling wastewater and putting it into the system, the demand on natural water supplies is reduced, preventing lakes and rivers from drying up. In fact, wastewater recycling periodically results in far fresher water pumped into lakes that refill them. This indirectly leads to more water replenishing groundwater supplies, if they exist. And with wastewater recycling, you don’t have to choose between sending water to thirsty people or thirsty crops. Both can drink from the same mix of recycled wastewater and natural water sources, depending on the availability of each. Recycling creates an endless local supply, so you don’t have to build massive canals or aqueducts to meet the needs of a developing area. And by recycling wastewater, you ensure that untreated waste doesn’t end up polluting local water sources.
There Are Available Solutions
The technology that can solve our freshwater crisis is already here and slowly being implemented around the globe. It isn’t as exciting or sexy as Silicon Valley’s innovations, but it has the greatest impact on quality of life and the ability to sustain life as anything else being developed.
This content reflects the personal opinions of the author. It is accurate and true to the best of the author’s knowledge and should not be substituted for impartial fact or advice in legal, political, or personal matters.
© 2018 Tamara Wilhite