What in the World is Going on with Our Water?
A Guest Post from Prime Movers Lab Advisor and Global Water Executive Chris Morrison
Not so long ago, water was just that safe, clean, and clear liquid that came out of the faucet — easy, available, inexpensive, and good quality. Now, we read about cancer-causing substances, PFAS, droughts, lead, sewer overflows, and even water prices (for bottled water) higher than a barrel of oil. To make it even more confusing, quality and quantity issues seem to be local, regional, and global. How can all of this happen at the same time?
Indeed, climate change has impacted the weather and water supplies. Let’s take 2021: droughts in Asia, record heat waves in Turkey, epic rainfall/flooding in Europe July 2021, Pacific NW heatwaves followed by massive rain and flooding, 100-year drought in California (2019–2021) followed by record fall 2021 rainfalls/snow.
For water agencies, non-dependable rainfall year over year requires water executives to expand supplies, raise dams, or build more storage. The problem for most parts of the world is that the “new water supplies” will be 10 to 100x more expensive than previous. Why is this? First off, the easy stuff was done earlier. Second, new technologies and sophisticated innovation cost money. Third, there is more public input and environmental-impact rigor in the permitting process, increasing costs to build new water systems. Fourth, there are more known contaminants to deal with today than 50 years ago, such as nitrates from fertilizer, pharmaceuticals, lead, and dangerous man-made chemicals that all find their way into our water sources.
Let’s review a few new water sources and counterbalance the benefits with the ecological impact of each:
Desalination — The costs for the membranes have come down significantly, but it still takes a lot of energy and requires extensive environmental approvals. Take the Poseidon Water plant in Carlsbad, CA, which took over $100M to permit and ten years to accomplish. This plant delivers 50 million gallons/day (189,000 m3) of fresh water to San Diego County, but the final capital cost was more than $650 million. That sounds like a lot, but this desal facility had the good fortune of being co-located with a power plant where discharge from the desalination plant could use the same discharge as the power plant’s cooling water system, saving the huge expense of having to build a deep-water brine discharge distributor (which can be more than 30% of the plant in some plants CapEx). Most desal plants now produce water via seawater reverse osmosis (RO) membranes.
The final result is that the Poseidon price for water is more than $2000/acre-foot (AF), which puts the cost of desal water far out of reach for most communities. For comparison, Los Angeles County (relying on long-term contracts with the state) can buy water at less than $1,200 AF, and existing lake water in San Diego is less than $500/AF. The Poseidon desal plant also consumes a great deal of energy (35 MW) with a CO2 footprint of more than 97 million metric tons (and this plant is hailed as the “most energy-efficient Desal plants in the world.”)
Raising existing dams to create more storage — When you raise a dam, you likely are impacting the downstream aquatic environment, fisheries, and potential off-takers below the structure. Careful studies by experts are required to examine and construct specific mitigations to minimize/eliminate the actual effects of these changes. In some cases, new requirements will be required to release water to mitigate the ecosystem challenges. Those mitigations can be huge, sometimes even more water than the “net” water collection from the dam raising.
More groundwater — There is a finite amount of groundwater. Building deeper pipes to collect more can cause other issues such as sinkholes, adjacent dry wells, inferior water quality, and infiltration of contaminants. Many cities have started regulating and restricting the quantity of water withdrawals and the drilling processes/depths. Groundwater is often contaminated and unusable without sophisticated and costly treatment.
Recycled water (irrigation) — Wastewater is treated to an acceptable standard (no pathogens) to be used for irrigating lawns, cooling towers, recreation areas, golf courses, and decorative landscaping. This purification usually requires significant post-treatment processes at the wastewater treatment facility with separate (purple) distribution pipes required for recycled water delivery. Most of these applications are typically within 5 miles of the treatment facility, as the cost for trenching and piping exceeds the savings in water.
Direct/indirect potable reuse — For more than 30 years, the International Space Station has been recycling all of its wastewater into drinking water, so the feasibility and technology are proven. The first major municipal indirect reuse system in the USA has been running successfully since 1986 in Orange County. Texas, New Mexico, South Africa, and California are working on direct potable reuse. (See the pros and cons of each here.) It is interesting to note that engineering firms are now saying that the quality of water from direct/indirect potable reuse may be substantially better than alternative sources (like Colorado River) and ~30% less expensive than desalination. Most importantly for water agencies, they do not need to pump water from hundreds of miles away as the water reuse plants “make” the potable water at a facility located within the agency’s boundaries.
As we move into a more sophisticated world, analytical monitoring and technology have raised awareness, creating new areas of concern. Until recently, most of us had never heard of PFAS/PFOS/PFOA (Per- and Polyfluorinated Alkyl Substances, or PFAS from here on out) as contaminants or certainly as suspected carcinogens. PFAS are widely used man-made chemicals (Teflon, firefighting foams, Gore-Tex, Stain-resistant carpet, etc.), which break down very slowly over time, some calling them “Forever Chemicals.” John Oliver recently did a very insightful piece on this (pardon the language): here
Because of their widespread use and persistence, PFAS residuals are now found in the blood of people and animals worldwide. PFAS are also now found in drinking water, air, fish, and soil at locations across the nation and the globe. Scientific studies have shown that exposure to some PFAS in the environment may be linked to harmful health effects in humans and animals.
Map of US sites — (from EMG.org)
EPA and US and global scientists are testing, studying, and analyzing data about PFAS impact. Understanding the exposure and risk of a substance is complicated. PFAS have been studied for decades, but in 2017, the International Agency for Research on Cancer (IARC) classified perfluorooctanoic acid (PFOA), which is a subgroup of PFAS compounds, as a possible human carcinogen. Many other global agencies are now actively engaged.
FROM EPA WEBSITE:
“Identifying the risk a chemical may pose to human health is a scientific process. It involves determining how much of a chemical is present in the environment, how much a person comes into contact with the chemical, and how toxic or harmful it is to people. Risk, or likelihood of harm to human health, is a chemical hazard and chemical exposure function. It is important to understand how toxic a chemical is and how much a person is exposed to it before health risks can be identified and steps to reduce these risks. For example, a chemical can be very toxic, but people are rarely exposed to it, so the risk to human health may be low. If another chemical is only moderately toxic, but people are routinely exposed to it in high quantities, then the risk to human health may be high.”
While federal standards are not yet in place for PFAS substances, 22 states have already adopted (with more states close to action) PFAS requirements for their drinking water, with New York, California, New Jersey, and Massachusetts leading the way setting a maximum level in drinking water of an average of 10 parts per trillion (ppt or ng/L). New York regulators announced on Dec. 23 their requirement to test all drinking water. The legislation requires that every consumer must be notified in the jurisdiction, should any well test above limits. While we all have no idea what the results will show, one can anticipate (from previous studies) somewhere between 5–10% of the 1,000s of the NY groundwater wells may test at/above the limit. This exercise has already started or been duplicated in many states, including Michigan, New Jersey, California, Massachusetts, and Illinois. Within 12 months, millions of consumers could be notified of concerns just within the USA, with other EU/Canadian and Asian nations also starting to test. No doubt, this will cause a frightened, concerned, and confused public. Want to learn more?
Several proven technologies exist to remove or capture the PFAS chemicals from water, but it is expensive and complex. There are three proven technologies to remove the PFAS contaminants from water, but none of these processes destroy PFAS. These processes are effective at making contaminant-free drinking water, but they all require transportation of the PFAS to another location.
● Granular Activated Carbon (GAC): This is the most widely accepted technology that absorbs the PFAS onto the active unused carbon and produces uncontaminated water (similar to a Brita filter, but more advanced). However, once the media is full of contaminants, the GAC must be removed, replaced, and properly disposed of or regenerated. The spent GAC is either transported to a landfill (creating potential future issues for groundwater) or put through an Incinerator process to burn off the PFAS (which produces unclear amounts of air pollutants).
● Ion Exchange (IX): In a similar method to GAC, polyvinyl beads (known as resins) are treated to enhance PFAS absorption onto their sites, remove the PFAS, and produce uncontaminated water. These spent resins must also be removed/replaced and disposed of upon reaching a specific capacity. The spent resin is either transported to a landfill (again creating potential future issues for groundwater) or put through an incinerator process to burn off the PFAS (which also produces unclear amounts of air pollutants).
● Reverse Osmosis (RO) membranes: Membranes are being used at several sites to remove PFAS from drinking water. The membranes concentrate the PFAS (which can’t cross the membrane) while producing uncontaminated drinking water on the other side (the membrane permeate). The downside is that membranes do not destroy the PFAS, so large volumes of liquid waste (“brine”) containing even higher concentrations of PFAS still must be transported and disposed of in an environmentally safe way. Currently, sites in North Carolina transport brine/PFAS concentrate from membrane systems to injection wells deep underground and others are discharging to rivers (surprisingly, with a permit, as PFAS is not regulated for discharge from wastewater plants).
So, we are really at a critical junction where the world needs to fill two technology gaps to help accelerate the removal of PFAS (and associated chemicals) from our drinking water.
From our viewpoint, we could use any/all creative insights to help accelerate the advancement of:
- Innovation in membrane technology — We must develop more selective membranes that can ‘pinpoint sieve’ and selectively remove PFAS from water, ideally using some of the newer, lower pressure membrane technologies. These membranes need to be able to minimize brine waste and concentrate the PFAS contaminants by 2–3 orders of magnitude (from ~50 ppt initially to 5000+ ppt).
- PFAS Destruction: While there are some promising and developing thermal/oxidation/reduction processes to destroy PFAS molecules, these innovations must be proven and must be able to perform reliably, without consequences at scale in hundreds of sites across the world. Often, water technology like this takes years/decades to be proven and we just don’t have that leisure in this case.
Prime Movers Lab continues to be interested in advances in both areas and would welcome input from our network and colleagues on any/all aspects to help solve our vital water quality and accessibility challenges.
Chris Morrison is an Advisor at Prime Movers Lab and has been a global water executive for over four decades.
Prime Movers Lab invests in breakthrough scientific startups founded by Prime Movers, the inventors who transform billions of lives. We invest in seed-stage companies reinventing energy, transportation, infrastructure, manufacturing, human augmentation and agriculture.
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