Acequia communities are agricultural communities that rely on self-organized participatory water allocation for irrigation. In North America, these communities originated with the Spanish colonization of the New World that took place towards the end of the 16th Century. Currently, functioning acequia communities in the United States are located in northern New Mexico and southern Colorado. As the first users of snowmelt water, these communities are threatened by future changes in climate. Projections for decreases in precipitation, increases in temperature, and prolonged, drastic periods of drought are all factors in possible future diminishments in stream flow. Other threats to acequia culture include reduced agricultural activity, an influx of newcomers buying second homes in the region, and farmers selling off their water rights. Practicing small-scale subsistence agriculture and allocating water collectively are two practices that may help acequia communities withstand future changes in climate and culture. System dynamics modeling uses stocks, flows, and converters to map out complex human or natural systems. Systems modeling can be used to create experimental situations to see how any system may respond to future changes. This professional project focuses on the development of a systems model for the Rio Hondo watershed. The Rio Hondo simulation models water availability, crop productivity and crop market value across five climate change scenarios, five alternative crop distributions, and three irrigation practices. The purpose of the simulation is to develop a quantitative understanding of how acequia communities in the Rio Hondo may be affected by future changes, with the hope of using the model to help farmers make informed management decisions regarding their future survival. The Rio Hondo watershed is approximately 75 square miles with headwaters originating at Wheeler Peak, New Mexicos highest mountain. The lower portion of the watershed is host to agricultural activity that takes place within the communities of Des Montes, Valdez, and Arroyo Hondo. The Rio Hondo simulation accounts for water use based on the current crop distribution within the watershed. Surface and groundwater interactions are assessed based on Darcy's Law to measure flow between two mediums. The simulation models ground and surface water interactions under flood irrigation techniques and two alternative scenarios using drip irrigation. Also, five alternative crop distributions are simulated to show the range of yields and resulting economic returns available to farmers in the region. Also, five climate change scenarios are used as inputs into the simulation to demonstrate the effect of future stream flow diminishments on the system. Under flood irrigation, the volume of the aquifer stabilizes, while under drip irrigation the aquifer volume diminishes by as much as 20%. Productivity is only heightened in the second drip scenario where the excess water is re-allocated by farmers in the region. In this instance, market value of crops increases by anywhere from 1.5 to 4 times the market value of crops in the flood scenario and the first drip scenario. The Rio Hondo simulation highlights the tradeoffs between economic vitality and hydrological health of the community and the watershed. The primary benefit of this preliminary modeling exercise is to generate conversation regarding the future viability of acequia farming in the Rio Hondo watershed and help farmers make informed water management decisions.
Irrigation farming--New Mexico--Rio Hondo Watershed--Computer simulation., Irrigation water--New Mexico--Rio Hondo Watershed--Management--Planning., Agriculture, Cooperative--New Mexico--Rio Hondo Watershed--Computer simulation., Subsistence farming--New Mexico--Rio Hondo Watershed--Computer simulation., Field crops--Economic aspects--Climatic factors--New Mexico--Rio Hondo Watershed--Computer simulation., Information modeling--New Mexico--Rio Hondo Watershed. Water-supply--Climatic factors--New Mexico--Rio Hondo Watershed--Computer simulation. Agricultural productivity--Climatic factors--New Mexico--Rio Hondo Watershed--Computer simulation.
Sabu, Sandeep. "Modeling acequia water use in the Rio Hondo Watershed." (2014). https://digitalrepository.unm.edu/wr_sp/65