Dust emission source characterization for visibility hazard assessment on lordsburg playa in southwestern New Mexico, USA

Authors: Van Pelt, Robert - Scott; Tatarko, John; GILL, THOMAS - University Of Texas - El Paso; CHANG, CHUNPING - Shanghai Normal University; LI, JUNRAN - University Of Tulsa; EIBEDINGIL, IYASU - University Of Texas - El Paso; MENDEZ, MARCOS - University Of Texas - El Paso

Submitted to: Geoenvironmental Disasters
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/30/2020
Publication Date: 12/10/2020
Citation: Van Pelt, R.S., Tatarko, J., Gill, T.E., Chang, C., Li, J., Eibedingil, I.G., Mendez, M. 2020. Dust emission source characterization for visibility hazard assessment on Lordsburg Playa in southwestern New Mexico, USA. Geoenvironmental Disasters. 7:34. https://doi.org/10.1186/s40677-020-00171-x.
DOI: https://doi.org/10.1186/s40677-020-00171-x

Interpretive Summary: Fugitive dust from wind-eroded surfaces degrades air quality, creates hazards to transportation, and negatively impacts human and environmental health. In the last 53 years, dust emanating from the area of the Lordsburg Playa in southwestern New Mexico has been responsible for visibility-related traffic accidents along a section of Interstate Highway 10 crossing the playa in which 55 people have died. In this study, ARS, University of Texas at El Paso, Hebei Normal University in China, and The Tulsa University examined potential source areas on and near the Lordsburg Playa and tested the surface with a Portable In-Situ Wind ERosion Laboratory (PI-SWERL) to estimate the critical wind velocities needed to entrain dust and the amount of dust the surface could potentially emit at those wind velocities. We found that certain areas on the delta of the primary drainage entering the playa and areas of relatively coarse sediments along the shorelines, particularly the western shoreline, are the predominant dust sources in the area.

Technical Abstract: Closed drainage basins with playas, ephemeral lakes, are a common feature of inland semi-arid and arid regions. These ephemeral lakes have received sediment from the surrounding upland for several millenia and throughout history many levels of water in the lake often result in a complex landscape and pattern of surface sediments. When dry, the playa-formed landscapes can be local sources of dust and PM10, particles with diameters less than 10 µm. One such ephemeral lake, Lordsburg Playa, in southwestern New Mexico is bisected by Interstate Highway 10. Dust storms emanating from the landscapes have been responsible for numerous visibility-related accidents and the loss of 55 lives in the last 53 years. We investigated the critical wind friction velocity thresholds and the emissivities of surfaces representing areas typical of the stream deltas, the shorelines, and the ephemerally flooded lakebed using a Portable In-Situ Wind ERosion Laboratory with stepped hybrid tests of increasing friction velocities and resulting shear stress. Mean threshold friction velocities for PM10 entrainment ranged from less than 0.30 m s-1 for areas in the delta and shoreline to greater than 0.55 m s-1 for ephemerally flooded areas of the lakebed. Similarly, we quantified mean PM10 vertical flux rates ranging from less than 500 µg m-2 s-1 for ephemerally flooded areas of lakebed to nearly 25,000 µg m-2 s-1 for disturbed surfaces in the delta, a 50 fold difference. The lack of PM10 supply limitation indicates that the shoreline and delta may be the dominant source areas.