In 2015, Moab experienced a surge in the public installation of water-harvesting landscapes. As threads of the global conversation on healthy watersheds and communities, these projects have aimed to educate by positive example. Through this work, we are put in mind both of the abundance of this valley, as well as our responsibility to steward its resources.
Regenerative water use is a major consideration for our municipality and county as development of urban and rural spaces accelerates, tightening corridors of pedestrian, bicycle and vehicle access, constricting resource flows (water, solar and agricultural land) and restructuring the familiar Moab aesthetic. As the permaculture design process teaches, it is the strategically diverse approach which serves us most effectively, providing resilience in redundancy while enhancing our competence to anticipate change through time. For a community in transition, planning that addresses multiple layers of social, economic and ecological needs is the basis for effectively managing an unpredictable future.
What is water harvesting? It is the capture and conveyance of water for storage or immediate use on-site. We are not removing water from the water cycle, nor stealing it from our neighbor. We are not treating water as a nuisance to be concentrated and dispatched. We are acting on observations of water’s most effective ecological role and adjusting our infrastructure to permit flows their healthiest course. Water harvesting understands water as a resource whose ecological function is defined by the meander of its flow. Just as a healthy river will curve and bow in its course, maximizing edge and surface area to foster increased life, the path of water from a roof through an urban landscape toward a creek is healthiest when slow, steady and cognizant of the soil.
Recent efforts have focused on passive water-harvesting systems. This is the immediate conveyance of water into earthworks, such as basins, ephemeral ponds, contour and conveyance swales and terraces. The land is shaped to hold and infiltrate water on-site, fostering vegetation, regenerating soil life and structure, managing stormwater and recharging aquifers. In other words, it is cutting a ditch to hold water instead of building a mound to accelerate water off-site. With a shovel and a level, this is the simplest way to manage water resources while supporting local ecology. Imagine the natural potholes up on Sand Flats. Recall how they hold water a day after the rains, fostering localized plant growth. Earthworks are similar collection points designed to create the conditions for life. Notably, they are applicable to most residential and commercial sites.
Then there is active water harvesting. This is the storage of water resources for later use. What do we do in the weeks, sometimes months, of seasonal drought? Though dry periods are offset in part by seasonal deluge, our designs must include adaptations to human need. For example, how do we keep a peach tree alive in Spanish Valley in July? If we choose to grow our food close to home, we must have the seasonal resources to do so. Active water harvesting with cistern tank storage provides this resource while decreasing strain on potable municipal water.
In October, USU-Moab, in collaboration with the Moab Area Watershed Partnership, installed a six-cistern, gravity-fed, active rainwater-harvesting system at the USU-Moab Bee Inspired Rain Garden. Funded through a Department of Water Quality nonpoint source pollution grant, this pilot project seeks to exemplify the function of active water harvesting as an essential tool in low-impact establishment of resilient landscapes, as well as a strategy for reducing the impact of stormwater across impermeable urban hardscapes.
To provide a sense of what is possible with active rainwater harvest, the following numbers outline the storage capacity of the cistern tank system throughout the year: Each cistern tank holds 530 gallons. The roof surface area draining to the cisterns is 4,500 square feet. For every inch of rainfall, 2,500 gallons of water are captured by the cisterns. This means, on an average rainfall year in Moab, the six cisterns will capture roughly 22,500 gallons of rainwater. This water will be used as needed seasonally, ultimately eliminating all reliance on municipal water supplies. In conjunction with passive water-harvesting earthworks and native vegetation plant palettes, the cistern tank system will foster an edible, drought-resilient, pollinator-friendly landscape in downtown Moab.
This is an example unique to its site. The project establishes a pilot initiative seeking to inspire future regenerative design approaches to home-scale and urban water management in the valley. Every building in Moab is its own watershed. This is the perspective we must begin with. The more sources we address on a site-specific basis, the greater the effect of our efforts across the valley. This way of thinking is a strategy available to everyone.
Jeremy Lynch is a certified water-harvesting designer chasing streams and stormwater around the valley. He is a member of the Bee Inspired Gardens Group and an educator and ecological design consultant with Moab-based In Transition Permaculture.
