Sustainable Water Management in a Passive Irrigation System

View the project report

Commodities

• Agronomic: corn, flax, hops, potatoes, soybeans, sugarbeets, sunflower
• Vegetables: sweet potatoes, beans, broccoli, cabbages, carrots, cauliflower, celery, cucurbits, eggplant, greens (leafy), onions, peas (culinary), peppers, radishes (culinary), rutabagas, sweet corn, tomatoes, turnips, brussel sprouts
• Additional Plants: tobacco, herbs
• Animals: bees

Practices

• Animal Production: pasture fertility, watering systems
• Crop Production: food product quality/safety
• Education and Training: technical assistance, extension, farmer to farmer, mentoring
• Energy: solar energy
• Farm Business Management: community-supported agriculture, risk management
• Natural Resources/Environment: carbon sequestration
• Production Systems: permaculture
• Sustainable Communities: infrastructure analysis, local and regional food systems, urban agriculture, urban/rural integration, community services, social networks, sustainability measures

Water is a precious natural resource of limited quantity and it is vital that we treat it as such. Perhaps even more so in the arid desert southwest, where many operations utilize flood irrigation systems without much consideration of the quantities of water actually being consumed. In recent months, unregulated agricultural water use has come under closer scrutiny in some Arizona communities. While there is much public discussion and regulations in place to protect our urban resources in the form of a drought preparedness plan, we would prefer to focus on develop a viable scalable plan to conserve agricultural consumption now rather than later and not continue to draw down on our existing aquifers. As a newly established permaculture test site in the Sonoran desert of Arizona, a critical element for us is water and the careful management of this critical resource. A priority for us, at Viking Agriculture, is to find ways to efficiently use and potentially re-use our natural resources to establish reliable systems to support and maintain nutrient dense food production. We feel that this is socially responsible and aligns with our core ethics. In other words, can we create a smarter, more efficient way to use the limited water resources that we have and still produce a high quality product? Equally important to us is the development of such systems that would pose limited negative impact on our soil. Current watering strategies used throughout this region include flood irrigation, surface watering and drip irrigation. These methods are deployed in various operations from the backyard hobbyist, to the market gardener as well as in larger commercial operations. At Viking Agriculture, we currently rely on a timed drip irrigation system in our permaculture test zone. This system provides sufficient moisture to our crops as well as providing a water source for the apiary that is also housed on the property. However, since one of our core values is to find ways to more efficiently use and potentially, to re-use our natural resources, it is of vital importance that we continue to improve on our current model to increase our bottom line while being socially responsible. Of equal importance, is to insure that any new systems that are implemented will limit impact on soil erosion and nutrient depletion while potentially increasing production of consumable product. Currently, we are experiencing some water loss through evaporation and runoff which, in turn, contributes to soil compaction and erosion.  

For the research component of our project, we propose to conserve and potentially reuse our water through the creation of grow beds with a subterranean irrigation system. Furthermore, we are interested in testing an additional variable incorporated into our model, aeration, and measuring its impact on the growth rate and health of our crop. Our experimental design is based on the general principles behind a passive hydroponics system and taking to another level; a passive subterranean irrigation system. To this end we will be deploying two techniques; a set of raised beds (popular to many local and home producers) and a traditional crop row system (common in both large scale and market garden productions).

Construction of this model includes the production of a series of moisture tight grow beds with water bank, a moisture wicking mat as a barrier between the water and soil material, clay aggregate substrate and topping off with local dirt, compost and soil amendment mixture. A select group of seasonal drought tolerant seeds and starters will be planted into one of three variations of the grow bed; with water bank, with water bank and aeration or without water bank. Data to be collected includes; quantity of water used, growth rate of plants, product yield, fecundity, and nutritional content of the resulting produce.  Additional projects may also incorporate surface watering or drip irrigation as a supplemental water source.

For the educational component of our project, we propose to share our process and resulting data with the community at large in a variety of formats. This may include presenting our project at local conferences and schools, hosting workshops, and conducting on-site tours. Our plan is to record the process from start to finish and be presented online as a youtube video documentary series. In addition, we hope to publish our results in publications that are readily available to other farmers as well as the general public. Open source downloadable materials; lesson plans, instructions, data results, will be made available through Viking Agriculture’s website and social media pages, i.e. facebook. We will be incorporating STEM (science/technology/engineering/math) themes throughout our deliverables in hopes of influencing the next generation of environmentally conscious farmers and scientists.