River Rail
We Can Clean Water with Our Earth
Agroceramicist Amara Abdal Figueroa writes on how locally sourced clay can be used to create natural water filtration systems.
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After the 2017 hurricanes, Puerto Rico’s water insecurity was widely exposed. As an island abundant in clay and water with a vulnerable electrical system, Tierrafiltra is addressing the island’s water quality by producing filters out of locally sourced clay. Analyzing local clay bodies is conducted in parallel to the construction of a network of wood and gas fueled kilns. By interpreting ancestral techniques and available open source technologies, Tierrafiltra aims to present a viable alternative to the dependency of imported materials, equipment, and high operational costs thus re-envisioning our landscape with a local filter. Collaborations with scientists, ISER Caribe, will allow Tierrafiltra to evaluate the microbiological effectivity of the water passing through different clay: combustible recipes. environment.
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Have you ever tasted water from a clay vessel?
It is one of the simplest and richest flavors of our planet.
Filtering water with clay is nothing new. Many of our ancestors around the world did it. I remember seeing storage vessels and water filters in the Middle East. It was the norm, especially before the discovery of oil.
We can clean water with our earth.
Proyecto Tierrafiltra is in the process producing an ecological filter in and for Borikén, or spirit of the earth, the pre-hispanic name of the island.1 In the aftermath of hurricanes Irma and María, I was strongly drawn to this rudimentary and sophisticated technology. In the Caribbean, we have an abundance of clay soils and rich water—what we lack is the confidence to purify it. The goal is to clean our precarious water and build a network of low-cost fuel-efficient kilns particular to Puerto Rico. The intention is to locally produce an accessible filter and catapult off-grid ceramic practices on the island.2
In January 2018, as a result of both rigor and chance, I was in conversation with Potters for Peace, an NGO that has contributed to the establishment of more than 50 filter factories in over 30 countries. They have provided continuous support working with filter makers and ceramists in rural Nicaragua for over 30 years. Ron Rivera, a global activist of Puerto Rican descent, a diasporican from the Bronx, and former international coordinator for Potters for Peace, dedicated his life to opening filter factories around the world.3 He strongly believed in the basic human right of access to potable water. His dream was to open 100 filter centers. I constantly ask myself, how is it there is not already a factory on the island? With our missions so closely aligned, Tierrafiltra aspires to be one of many interconnected and simultaneous efforts that will continue his legacy.
Rivera was crucial in standardizing the water filter by developing a two part mold. The recipe of clay and sawdust gets pressed into a flowerpot form.4 When fired, the sawdust burns away, leaving numerous holes for the water to pass through the winding paths of the porous filter, trapping bacteria and viruses: a property known as tortuosity. The resulting filter has an ideal flow rate of 1 to 2 liters per hour. Coating the filters with colloidal silver, an antibacterial, serves as an added layer of protection. The result: clean, fresh water.
The regulation of the filter by Rivera allowed Potters for Peace to develop a protocol, which they sent me to study in Borikén. The proper mix of materials and temperature levels is critical to the production of a microbiologically effective ceramic water filter. Extensive testing, recording, and interpretation of the results must be conducted to determine the proportion of clay and combustible material, and optimal firing temperatures that work together best in each terrain. As a result of this self-directed research with Potters for Peace, I took their exploratory course which culminated with a certification to open and direct a filter production center.
In my practice between art and architecture, oscillating between object and infrastructure, I have identified the basic needs of a range of ceramicists in Puerto Rico. One of the main concerns for those working with imported clays is that these are overpriced, which makes relevant the study of locally sourced clay an endangered practice.5 Another common concern is that the ceramic pieces being fired are not reaching the temperature needed to become solid. This is due to the inconsistency of the compromised electrical utility infrastructure or the varying temperatures in pit firing. Vitrifying a filter requires a sustained and regulated firing of at least eight hours.6 To address these shortcomings, we must acknowledge that clay is a viable resource based on the Clay Testing Protocol and our indigenous precedents.7 Examining clay bodies for water filtration in Puerto Rico requires producing a hydraulic press mold and building a “Mani” kiln that can stack up to fifty filters per firing.8 By setting up a small scale filter factory, developing the recipes, pressing the filters, training kiln operators, and incentivizing educational programming, all the collaborators within the space will be able to take this knowledge with them. The challenge is to create a business model in which we can make this project sustainable in a financially austere Puerto Rico.
I see the water filtration project as one that can have a ripple effect in off-grid communities, incorporated into educational ecological projects, as well as art practices by fomenting a technical discourse near natural clay deposits and soon-to-be-built kilns. It is a reclaiming of territory, a response to the land grab: a way of taking back our land.
This everyday object can improve our health, our current material culture, and our relationship with our environment. It is a proposal of collective healing. How can we heal our bodies within our landscape? By cleaning our water with our clay.
I cannot claim that this filter is the solution of all our rooted problems, but I can say that it is just one way to contribute a local proposal that assumes more authorship.
I will continue this vision in the way I know how: rallying local and international thinkers, makers, and activists through ceramic arts. Each kiln firing will provide many lessons through intrapersonal collaborations with each other and our elements. This will reconnect us with our earth.
And now, let’s clean water with clay, salud.9
- Bori = espíritu = spirit (of the) kén = tierra = earth
- MAATI (2012) is an interdisciplinary project that integrates regional traditions and ceramic precedents from around the world to serve as a resource for ceramic practitioners in Medellín, Colombia founded by Andrés Monzón, Parul Singh, and Amara Abdal for the International Residency Program at the Campos de Gutiérrez Foundation. Through research, educational programming, and production, it aims to contribute to the viability of ceramics and serves as focal point for local and international conversations about the role of ceramics in contemporary art and quotidian objects.
- Ron Rivera first became passionate about ceramics in the early 1970s when he studied in Cuernavaca, Mexico with Paulo Freire, Brazilian educator and philosopher, and Ivan Illich, political and educational theorist, who taught that human beings had lost their connection to Earth.
- From New York, when the severity of water insecurity was made visible due to the hurricanes, my response was to mix clay with a variety of combustible materials. In 2016, on one of my visits, I approached the island’s clay and met a collective studying materials of biological origin: they are a source of sawdust. “Modernity, linked to the neoliberal paradigm has disarticulated local production, among other reasons, by the imposition that almost everything has to be imported from the continental United States. In Puerto Rico some want to rid us of our tools” MAOF, MAOF. (RRD, Mexico, 2018), 113.
- In February of 2018, upon receiving Meghan Stotko shortly after her participation in a learning brigade in Nicaragua with Potters for Peace, we attempted our first kiln construction modeled after the Dougie kiln at Camp Tabonuco, a platform for arts, education, and the environment. The kiln is named after Douglas Naum, a young Nicaraguan potter and filter maker, who incorporated a steel barrel into the chamber to hold the bricks making it easy to build and accessible for earthenware production. Despite this kiln being low-budget in Nicaragua, in Puerto Rico we face another reality. Due to the eradication of local ceramic and brick production, we are forced to purchase expensive imported bricks, making the kiln too expensive. Besides our constant mining for second-hand bricks, we can take advantage of the thermal properties of defunct electric kilns by converting them to fuel off propane or wood, just like how Steve Smith has recently converted my mom’s old English kiln. Our kilns are experiments. The next Dougie will have fired brick fireboxes and ‘cobb’ bricks over the barrel. In these processes, we will be able to make some bricks for future kilns which can also produce the elements for the next and so forth.
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In the case of the ceramics facilities at la Escuela de Artes Plásticas y Diseño in Old San Juan, due to an inconsistent electrical transformer, the firing temperatures have been limited: for example, a kiln that normally used to reach mid-firings (cone 6) now only reaches low-fire temperatures (cone 04). Although there are electric kilns that work for artistic and artisanal practices around the island, their use is hindered by the high electric costs susceptible to the Electric Energy Authority. Particular to the filters, it is ideal to build hybrid kilns, wood and gas fueled, so as not to depend on a single source. It is also not feasible to use electric kilns for filter production since the sawdust that burns of the filter during the firing deteriorates the metal electrical elements of the kiln. Having established kilns for filter production, the infrastructure is accessible for a range of ceramic practices.
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“The peculiar archeology of the first agro-ceramists (called huecoides, saladoides, or igneris) is the excellency of their ceramics, which possessed a high technical and artistic expression. They dominated ceramics in each step of their production process: they knew how to adequately source clay, add the precise proportion of an inclusion so that it wouldn’t crack, make—by coil building—thin walled vessels and fire them at high temperatures which obtained a standard not surpassed by any following Antille culture.” Sebastián Robiou Lamarche, Taínos y Caribes: Las culturas aborígenes antillanas. (Scotts Valley: CreateSpace Publishing, 2016), 44.
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The “Mani” kiln is named after Manny Hernández, a cross draft fuel-efficient kiln made of earthenware bricks. This design has become popular in Central America and is ideal for the production of ceramic filters since these are not required to reach high temperatures. However, building the same kiln with more refractory bricks will allow us to save fuel, since it insulates the heat more effectively; additionally, we would have the ability to rise to even higher temperatures, which will allow us to facilitate future material research.
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With the Materials-Based Research Grant with Center for Craft, Tierrafiltra in collaboration with Iser Caribe & Inocencio Alvarez, has been able to locally assemble a hammermill, sandcast and a machine, set of aluminum molds, start assembly hydraulic filter press to then test the water quality of iterative filter recipes throughout this process.










