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Of Dinosaur Pee and Aquifer Re-injection: Dilemmas in Water Reuse

By Daniel Moss Thirsting for solutions to an exploding water crisis, there's much talk about water reuse. At a recent conference of Mexican water distributors, two starkly different strategies were on display. In one scenario - causing some noses to wrinkle - consumers are asked to drink chemically-treated wastewater that has been re-injected into aquifers. In the other, they slake their thirst on water that's been used, but generally only by ecosystems filtering water over time. Conjuring up prehistory, International Water Association Board Member Daniel Nolasco, described this re-used water as “dinosaur pee”....

Photo caption: As climate change and mismanagement leave communities unsure about the integrity of their water supply–think Capetown and Flint–onsumers want a guarantee from their water utilities that their families can count on healthy water for generations to come. Photo by World Bank/Flickr

By Daniel Moss

Thirsting for solutions to an exploding water crisis, there’s much talk about water reuse. At a recent conference of Mexican water distributors, two starkly different strategies were on display. In one scenario – causing some noses to wrinkle – consumers are asked to drink chemically-treated wastewater that has been re-injected into aquifers. In the other, they slake their thirst on water that’s been used, but generally only by ecosystems filtering water over time. Conjuring up prehistory, International Water Association Board Member, Daniel Nolasco, described this re-used water as “dinosaur pee”.

Technically speaking, all water is re-used – that’s the nature of a closed hydrological cycle. The questions that the water industry faces today – and that regulators and customers must consider – is which water to re-use, for what and how. In a sense, it’s a classic technology vs. let-nature-provide dilemma, perhaps not so different than the controversy about how to best guarantee our food supply – in that case, by genetically modifying seeds or selecting and crossing naturally-occurring seed varieties. As with food, booming populations are demanding more water, becoming more irregular in the era of climate change.

Urban Water Dilemmas

In the conference session, “Challenges in the provision of water to cities: New sources of supply”, speakers described panicking cities. With existing sources contaminated, overexploited or both, mayors urge their engineers, “find us a new water source.” And yet pumping water from neighboring jurisdictions can mean big energy outlays, expensive infrastructure and political tensions as localities battle over the precious liquid. The idea of potabilizing used water in one’s own backyard can seem appealing.

Dr. Gabriela Moeller Chavez of the Mexican Association of Engineering, Science and Environmental Management (AMICA) advised caution. She warned of unintended consequences when groundwater reserves are built back by re-injecting treated wastewater into aquifers. For both technical and political reasons, regulators often have difficulty establishing maximum permissible limits of hazardous materials that may appear in aquifers – it can be quite a toxic cocktail that gets flushed down toilets and storm drains. “We simply can’t regulate all contaminants. It’s a huge number to keep track of.” As the number of chemicals in use rises and corporations push against restrictions, effective regulation is likely to become even more challenging . “Be cautious with technology,” she counseled. “Existing treatment plants just can’t treat everything.” The “precautionary principle”, which would subject chemical use to more stringent scrutiny before being authorized is not broadly applied.

Trust and Technology

 It’s not as if people don’t warmly embrace new technology – look at the embrace of smart phones and artificial intelligence. But mixing experimental technology with the water supply can cause hesitation; it requires trust between consumers and water companies. Many water companies simply don’t have a stellar reputation to fall back on – think Flint. The water that utilities provide sometimes smells funny. It’s off-color. Service is intermittent. It’s too expensive. “How can you convince people to drink scarlet water?” asked Dr. Moeller. “

Billions of consumers around the world seem to have already cast judgement on their water provider – they buy bottled water (often unregulated and sources for which are also at risk). Rightfully or not, the idea of drinking re-injected water – especially when playfully smeared as “from toilet to tap” – may push more people away from the faucet.

Distrust in tap water may have little do with the competency of the water company itself. The politics behind sub-standard water service are complex; forces that undermine water company performance include reduced state and federal support to municipal water providers, pursuit of unsustainable economic development strategies that despoil watersheds, weak enforcement of environmental and water quality regulations, nil inter-agency cooperation for watershed protection, and so on. But the public-facing agency that receives the brunt of the blame is generally the water utility. Trust is unlikely to be repaired until there exists a truly enabling environment for drinkable water.

Winning with Watersheds

To improve water quality and quantity while building public trust, Daniel Nolasco suggested letting, “nature treat water” and adopting, “a watershed perspective.” He discouraged “linear, extraction economic thinking and instead, the logic of a circular economy.” That circular economy lifts up recirculated dinosaur pee.

In a survey of Mexican water companies commissioned by the National Association of Water and Sanitation Operators (ANEAS), source water protection was highlighted as a good investment not only because it saves money over the long-term – treatment costs creep up as watersheds degrade – but because it generates a positive public perception and can improve collaboration with upstream communities. A customer who sees their water company looking out for the integrity of their grandchildren’s water supply is a happier customer.

During a conference panel, “Strategies to protect watersheds and sources: The first step in re-using water”, Leonardo Lino Briones, Director General of Leon’s water utility, described his company’s philosophy: “Providing water begins with protecting the source.” Their educational video shows their customers how the nearby mountain range provide pristine water. Lino insisted that the utilities’ source protection efforts have to “work in economic terms”, which means that costs can’t be absorbed solely by the water utility – which would be unfair to customers as it is generally other users that contaminate and degrade upstream sources.

Although not a large utility, Aguas de Saltillo, to Leon’s north, has a geo-hydrology department, in-house staff that monitor aquifer health. Marcela Carmona explained that they collect data to pinpoint where to pursue other source protection measures like reforestation. The utility organizes walks in the watershed for urbanites to discover where their water comes from. Nearly 50,000 customers voluntarily contribute to a source water protection fund overseen by Profauna, an environmental organization with which the utility has partnered.

Tajín Fuentes, director of the NGO, Sendas, shows a model of the Pixquiac watershed, the source of Xalapa, Mexico’s water.  Sendas works with upstream farming communities, the water utility and state and federal agencies to protect and rehabilitate the watershed.

Working in the mountains above Xalapa, Veracruz, Tajín Fuentes of the NGO, Sendas suggested creating watershed management plans, “with citizens who live in the watershed. Otherwise the plan just sits on the shelf.” Sendas works with upstream communities on a payment for environmental services program (PES) – to which the water utility contributes – to incentivize sustainable cattle-ranching and agriculture. These poor practices cause watershed deterioration and poor water quality. “There’s a tendency to see the water operator as the only one to put up money,” said Fuentes. In Xalapa, PES incentive programs receive federal support from the national forestry commission, CONAFOR, and state support from the Veracruz Environmental Fund or FAV in Spanish. In response to growing work in this area, the water utility now has a watershed management department. Both Xalapa and Saltillo participate in the Cities and Watersheds program of the Mexican Fund for Conservation of Nature.

Electoral politics can be the enemy of watershed protection. Watersheds can’t be rehabilitated over a four year political term. Incoming mayors may wriggle out of water source protection commitments. Water advocates within Sendas and the city of Leon seek to stabilize their work by establishing watershed councils and oversight bodies for the water utility. Active citizen participation can keep a conservation agenda on track in the face urban sprawl and damaging economic development strategies – which water operators, as public agencies, may be hard pressed to oppose. A longer term solution heard frequently at the ANEAS conference – and applicable around the world – is for water utilities, while remaining public, to have some autonomy from municipal governments.

Safe Water on the Horizon

It’s a time of enormous creativity in urban design and water re-use. Cities like San Francisco have adopted new zoning requirements that stipulate grey water re-use and rainwater capture within buildings of a certain size. Increasingly common around the world are pocket parks, sidewalks and parking lots that channel stormwater to improve aquifer recharge. While these water re-use strategies are not generally politically risky, they require new ways of thinking and adequate budget allocations.

More contentious is rethinking how watersheds are managed, an essential conversation if consumers are to be reassured that their drinking water is secure. It’s not at every water utility conference where watershed conservation strategies are debated alongside traditional engineering approaches. Use of the term green infrastructure at ANEAS was helpful; it reassures engineers that source water protection is not anti-technology but rather smart technology that mimics natural processes and invites participatory stewardship of ecosystems. Wouldn’t it be serendipitous if the climate crisis drives water utilities to lead watershed rehabilitation efforts and their customers can confidently drink from the tap?

Daniel Moss has worked in community-based resource management in the U.S. and Latin America for 30 years. He writes on water issues for a variety of journals and blogs and directs Water Commons. He recently published a study entitled, “Urban Water Utilities and Upstream Communities Working Together, about how Latin American water operators collaborate with upstream communities for watershed protection and participatory water governance.

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