These data represent low-lying lands and intertidal lands on Dauphin Island, Alabama, USA for January 2015. These data were delineated using airborne lidar elevation data, in situ elevation observations, lidar metadata, and tide gauge information. We applied Monte Carlo simulations to incorporate uncertainty into a digital elevation model and produce probabilistic outputs with regards to elevation relative to tide and water levels. Specifically, these include three error treatments, including leaving error untreated, and treating error via simulating the propagation of error using Monte Carlo simulations with error and bias estimates from the lidar metadata and site-specific Real-time Kinematic Global Position System data, respectively. This data release also includes a sensitivity analysis to help visualize how a suite of alternative error and bias values affect the Monte Carlo simulation results for the identification of low-lying lands. This data release includes the following three components, which are included in the attached ZIP file: 1) low_lying_lands directory which contains presence/absence rasters for low-lying lands (Raster data) and validation points for low-lying lands (Vector data); 2) intertidal_lands which includes presence/absence rasters for intertidal lands (Raster data); and 3) senstivity_analysis which includes presence/absence rasters for low-lying lands for various alternative bias and error parameters (Raster data).