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During the second week of June 2009, the UNM Masters of Water Resources students, staff, and collaborators studied the Mora River watershed by measuring flows and water quality characteristics at over 20 surface water sites in the watershed. The main objective of the study was to conduct a river assessment of the Mora River and its corresponding acequia systems. It is expected that this report will serve as a baseline for future research on the hydrology, water quality, and to a lesser extent, the socioeconomic characteristics of the river and its watershed. The Mora River watershed drains 1,476 square miles and is located on the eastern slopes of the Sangre de Cristo Mountains in northeastern New Mexico, originating in mountains with elevations over 12,000 feet above sea level. The Mora River then flows eastward onto the eastern plains of New Mexico, draining into the successively larger Canadian and Arkansas Rivers, which ultimately make confluence with the Mississippi. Approximately 47 acequias, or irrigation ditches, intersect the Mora River and its tributaries throughout the watershed. The principal source of water supply in the watershed is surface water, and most is used for agricultural activities consisting of irrigation and livestock watering. Drinking water is supplied almost entirely by ground water although there are reports of a few homesteads that use water from acequias or adjacent streams for domestic use. Measurements and site descriptions were recorded either on New Mexico Environment Department Surface Water Quality Bureau data sheets or in notebooks, following the EPAs Environmental Monitoring Assessment Program (EMAP) protocol. Data was collected and analyzed concerning the hydrology, geomorphology, riparian vegetation, human impacts, benthic macroinvertebrates, and water quality at five segments of the Mora River, and 19 tributaries and acequias. This assessment found that generally high quality conditions of the river and riparian environment. This conclusion was supported by the type and diversity of benthic macroinvertebrates, by channel geomorphic criteria, and by water quality measurements. However, it is recognized that this assessment was done near the peak of spring runoff; it is likely that low flow conditions later in the summer will present environmental stresses to the system. In this regard, the nearly complete diversion of the Mora River for agricultural use as it passes through the Mora Valley was noted. Much of this water is returned to the river at the eastern end of the valley and has measurably increased concentrations of plant nutrients including nitrogen and phosphorous species that may result in eutrophic impacts. Recommendations are included for further studies to quantify stream flows and diversions in the watershed to gain a better understanding of water use. Information is also needed on the seasonal concentrations of chemical constituents in the river and its tributaries to understand the impact of development, especially that associated with non-residential vacation homes and potential development of coal bed methane.
Water quality--New Mexico--Mora River Watershed., Stream health--New Mexico--Mora River., Watershed hydrology--New Mexico--Mora River Watershed., Irrigation canals and flumes--New Mexico--Mora River Watershed.
Thomson, Bruce M. and Abdul-Mehdi Ali. "Water resources assessment of the Mora River." (2009). http://digitalrepository.unm.edu/wr_fmr/3