The site is located on land within the San Bernard Wildlife Refuge, Brazoria County, Texas (29°09'57.9"N 95°49'43.4"W) at an elevation of about 16 m above MSL, and is part of Ecoregion III Western Gulf Coastal Plain and Ecoregion IV Floodplain and Low Terraces, dominated by mixed bottomland hardwood forests (Griffith et al. 2007). Bottomland forests of pecan (Carya illinoensis), water oak (Quercus nigra), southern live oak (Quercus virginiana) and elm (Ulmus spp.) are typical, with some bald cypress (Taxodium distichum) on larger streams. Other common tree species are ash (Fraxinus spp.), sugar hackberry (Celtis laevigata), cottonwood (Populus deltoids) and black willow (Salix nigra). The tree heights range from 15-25 m. The climate of this region is classified as Humid Subtropical (Cfa) under the Köppen–Geiger climate classification system (Koppen 1900). The average annual maximum temperature is approximately 26 °C and the annual minimum temperature is approximately 15 °C. The area receives a mean annual rainfall of 1143 mm, with an average relative humidity of ~70%. The sites are located in the Linnville Bayou watershed of the San Bernard River Basin. As these forests are situated in the floodplain, sloughs are a common occurrence, which inundate significant parts of the forest. The soils are mainly vertisols and alfisols dominated by clay, loam and sandy loam texture. The soils series include Aris fine sandy loam, Bacliff clay, Edna loam, Leton loam, Pledger Clay and Churnabog clay.

The Texas Water Observatory (TWO) is a distributed network of field observatories in Brazos River corridor and was developed to better understand hydrologic flow across natural and manmade reservoirs in the critical zone. The network monitors and measures groundwater, soil water, surface water, and atmospheric water at multiple locations across space and through time.