The struggle of water conservation and allocation is constantly on the minds of those living in arid and semi-arid climate zones. This precious resource is stretched thin over these regions, with conservation ordinances in place that limit water usage for activities like growing your own food. But in a time where home food production is becoming increasingly important, how do we address small-scale, efficient irrigation in water-stressed regions?
Lori Haynes is from Dripping Springs, Texas, located just west of Austin. Ironic name for a town in Central Texas where water availability is a constant strain on the population. Lori and her husband settled there in 2009 and quickly made a conscious decision to use rainwater as their water source, rather than adding pressure on the areas underground sources. Once the move was squared away Lori began to pursue her gardening hobby, despite the challenge posed by Texas heat. However, the summer of 2011 brought a hard drought to Dripping Springs; “We had truck deliveries about once a month to deliver 2000 gallons and that supplied the house and any irrigation,” Lori says. “I had started researching different irrigation methods and I came across clay pot, or olla, irrigation.”
An olla (pronounced “oh-ya”) is a clay pot buried to the neck and filled with water. Unglazed and fired at a low temperature, the clay remains porous allowing water to seep through the walls and directly irrigate surrounding roots at a continuous slow rate. The agricultural benefits of olla irrigation are numerous: the soil surface remains dry, reducing compaction and weed germination. Additionally, runoff and evaporation are eliminated allowing plants to absorb nearly 100% of the water (giving ollas an application efficiency of nearly 100%). Other irrigation techniques are not nearly so efficient; of the main methods of irrigation, drip irrigation is the most efficient with an application efficiency of around 90%. Sprinkler irrigation and surface irrigation follow with application efficiencies of 75% and 60%, respectively. The high efficiency of clay ollas vastly reduces water loss as well as watering frequency, a win win for busy homeowners!
Lori could not find a local olla source, but was determined to test the technique out. She experimented by gluing two terra cotta pots together, and discovered that the overall idea behind the system worked incredibly well. She began talking to local potters about possible production, and after a long search found a pottery manufacturer who was willing to take on the project. Her goal was to make this “ancient technique of low tech, low cost irrigation” available to anyone looking for an irrigation solution, and ollas have demonstrated their success and versatility in many climates. Now, Lori’s terra cotta experiment has evolved into Dripping Springs Ollas, and her ollas are available at retailers in Texas, Louisiana, and Virginia.
Though we did not get a chance to visit Texas during our voyage, we maintained contact with Lori and thank her for her flexibility and support. We cannot wait to meet her in the future!