By Quita Ortiz
For the past decade, Dr. Sam Fernald, a watershed management professor in the Range Sciences Department at New Mexico State University, has led an effort to research acequias, New Mexico’s centuries-old irrigation and water governance system, in the community of Alcalde in Rio Arriba County, specifically surrounding the hydrology characteristics of acequias and how they interact with shallow groundwater. This acequia hydrology research dates back to the early 2000’s and a few years later a land use change analysis in Alcalde was incorporated into Dr. Fernald’s hydrology research to gain a better understanding of how land use change can impact water management, riparian ecosystems, and acequia culture. Knowing that acequias were at particular risk due to increasing urbanization pressures and the potential impacts on actual water use, water quality, and riparian vegetation along irrigation ditches and streams, the connections between land use and water management were apparent.
Dr. Fernald’s early hydrology studies were promising for acequias, indicating a reciprocal relationship between flood irrigating and groundwater recharge as well as contributing to the riparian vegetation in our communities, generating ecosystem services by providing a diverse habitat for wildlife. He’s been persistent at obtaining funds to continue and expand this research and was successful in obtaining a grant from the National Science Foundation (NSF), which is currently funding a four-year multidisciplinary research effort to model the sustainability of acequias. This study is taking acequias into account as holistic systems that link water, environment, and cultural livelihood. This research aims to understand how and why acequias have remained resilient in face of urbanization, ever increasing water demands, and climate change. Project partners include NMSU, UNM, New Mexico Tech, Sandia Laboratories, and the New Mexico Acequia Association.
The human aspect of acequias has now become part of this process and researchers are now studying acequias in a much more inclusive manner, characterizing them as the sustainable water management systems that they embody. Furthermore, they’re being researched on a larger geographic scale by establishing the link between the valleys that acequias irrigate and their upland watershed, not only as the source of water but also taking into account the land base from which acequia users harvest timber and graze livestock.
The current research effort, which is now in its third year, expanded the study site from Alcalde to also include acequias along the El Rito (Rio Chama tributary) and Rio Hondo (Rio Grande tributary) stream systems in north central New Mexico. All three sites support acequia-related activities, but they differ in their physical geography, water availability, and spatial patterns such as proximity to urban centers.
There are number of threats to acequia communities that have been identified including population growth, climate change, and policies that regulate land and water resources. Acequias have a good track record for their ability to adapt to changes that have been induced largely by urbanization and modified economic structures. But they are now facing challenges with increased intensity and complexity. Examples include prolonged drought and determined water markets aimed at transferring water out of rural communities to other uses.
Using different modeling approaches, the hydrology results show that seepage from earthen ditches and field percolation recharge the shallow aquifer. This, in turn, becomes groundwater flow for future use as it holds the water upstream for a longer period. Floodplain models indicate that groundwater recharge would be affected if earthen canals and their related activities were eliminated, reducing overall aquifer recharge. So even though there are technologies that are intended to conserve water, they don’t address the fact that there’s a key connection between surface and groundwater supplies. Drip irrigation, for example, might conserve upfront water use, but it’s also allowing more water to run downstream sooner.
Dr. José Rivera, a UNM professor at the School of Architecture and Planning, has led the sociocultural research surrounding this study and was assisted by retired UNM professor, Dr. Sylvia Rodriguez, and the New Mexico Acequia Association staff. Focus groups were conducted in summer 2012 at the different study sites and gleaned a wealth of sociocultural data surrounding acequia water sharing and distribution customs; water governance; food, seed and agriculture traditions; land use and land ownership trends; livestock and ranching trends; and mutualism, which involves community cohesion such as shared cultural values and participation in other community endeavors (for example, livestock associations and mutual domestic water associations). In other words, this facet of the research attempts to understand why acequias maintain their traditions despite the many external forces working against rural livelihoods.
Other data that were incorporated into this study include economics and land use. Future steps include integrating all of the quantifiable data into a model which can then simulate different scenarios that depict the sustainability of acequias. This involves using the two major stressors, population growth and climate change, to determine amount of stress that would impose irreversible impacts to the entire system. Hopefully this data will provide acequias with a framework that assists them in recognizing steps that would help to evade potential negative scenarios. The goal of this research is to determine how acequias can provide insight into resource sustainability by understanding their capacity to adapt; and identify potential strategies for acequias to continue adapting to ongoing changes in the areas of economics, resource policy, and climate change.
From an academic perspective, we’re beginning to understand the relationship between acequia irrigation ditches and the natural environment at the regional watershed scale. Most acequia research endeavors to date have been segregated into different fields—policy, local water governance, water rights adjudication, water transfers, land use change, agricultural economics, etc. However, this study is the first in New Mexico that views acequias as the complex system that they symbolize. An acequia is not simply an irrigation ditch; rather it represents a multifaceted system characterized by humans that have historically worked with the environment in a sustainable manner by combining water governance, agriculture, resource management, and cultural identity.
As part of this NSF-funded research effort, the group will host a symposium, “Acequias and the Future of Resilience in Global Perspective” which is being coordinated by Dr. Sylvia Rodriguez. It will bring together scholars from around the world to share their research on similar human-environment systems. The symposium will be followed by a workshop featuring panelists that are working on acequias issues in New Mexico to discuss the future steps that are necessary regarding research and policy to ensure ongoing acequia resiliency. It will be held at the Las Cruces Convention Center on March 2nd and 3rd. To register for this event visit http://globalperspectives2013.wrri.nmsu.edu/. If you have questions about this event or this project, feel free to contact NMAA.