Hillslope hydrological monitoring data in Puerto Rico, October 2021 to September 2025

This data release includes time-series data from 18 monitoring stations installed in Puerto Rico following Hurricane María in 2017, which led to over 70,000 landslides across the island (Hughes and others, 2017). The first two stations were installed in July of 2018 (Smith and others, 2020) to investigate subsurface hydrologic response to rainfall and develop a quantitative link between rainfall, soil moisture, and landsliding. As of the time of this writing, there are 18 stations, including the two original stations that have undergone some revision.

Instrumentation was designed and installed in collaboration with the University of Puerto Rico - Maygüez to continuously measure precipitation, volumetric soil water content, soil water potential, and pore-water pressure, logged at 5-minute intervals. Sites occasionally also included air temperature and barometric pressure instrumentation. An electronics enclosure with a solar and battery-powered data logger, a rain gage, and an instrumented soil pit comprises each site. A detailed description of the sensors follows.

Tipping-bucket rain gage instruments were either a TB4 tipping-bucket rain gage with 0.1 mm resolution with 0-250 mm/hr or 250-500 mm/hr accuracy of +2% and +3% respectively, or a TE525-L rain gauge with 0.254 mm resolution and accuracy of +1% up to 50 mm/hr, both from Texas Electronics (Rain_mm_Tot in data tables). Air pressure (atmos_pressure_kPa) was measured using either Geokon vibrating wire piezometers (4500AL-70kPa type with 0.025% Full Scale (F.S.) resolution and +0.1% F.S. accuracy) or a Campbell Scientific CS106 barometer with accuracy of +0.3 hPa, +0.6 hPa, +1.0 hPa, and +1.5 hPa at +20oC, 0-40oC, -20o - +45oC and -40o - +60oC, respectively. Air temperature was measured using Geokon vibrating wire piezometers (4500AL-70kPa type) with temperature accuracy from -20oC to 80oC, and resolution of 0.025% F.S. minimum.

Subsurface sensors, installed in the uphill wall of hand-excavated pits roughly 1 m deep, measured soil moisture at four depths (depths indicated by sensor names in data tables) using Meter Teros 10 soil water content sensors with an accuracy of +0.03 m3/m3 and a resolution of 0.001 m3/m3. Meter Teros 21 sensors were installed at 3 depths to measure soil water potential and had a range of 0 to -100,000 kPa with an accuracy of +(10% of the reading + 2 kPa fixed error) over a range of -100 to -5 kPa and a resolution of 0.1 kPa. Total fluid pressure at the maximum excavation depth was measured using Geokon model 4500AL-70kPa standard piezometers with 0.025% F.S resolution and +0.1% F.S accuracy (pressure was offset to zero during sensor installation to account for factory calibration to read zero at sea level). 12V solar panels and batteries powered the stations, and cellular telemetry transmitted the data to office computers.

The data presented in this report have not been modified from their original state as recorded by the dataloggers, which were programmed to return sensor values in engineering units and may contain inaccuracies due to equipment malfunction, calibration drift, or other factors. Missing data are indicated as “not a number” (NAN) and generally reflect sensor failures; numerous sensors were replaced after installation because of failures.

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
 
 
References:
Hughes, K.S., Bayouth García, D., Martínez Milian, G.O., Schulz, W.H., and Baum, R.L., 2019, Map of slope-failure locations in Puerto Rico after Hurricane María: U.S. Geological Survey data release, https://doi.org/10.5066/P9BVMD74.
 
Smith, J.B., Thomas, M.A., Ashland, F., Michel, A.R., Wayllace, A., and Mirus, B.B., 2020, Hillslope hydrologic monitoring data following Hurricane María in 2017, Puerto Rico, July 2018 to June 2020: U.S. Geological Survey data release, https://doi.org/10.5066/P9548YK2.