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The USGS Water Mission Area has recently completed a migration of groundwater field visit data from a legacy data system to a new, centralized datastore. Alongside this work, we have been building a new modernized dataflow (technical blog post coming on that soon) as well as bringing the display of groundwater field visit data on the monitoring location pages.

Screenshot of a graph showing field visit data as red circles along with instantaneous values which are charted as a blue and orange line

Image of hydrograph from CT-SC 22 SCOTLAND, a well in Windham County, CN containing field visit and instrumented groundwater level data

Field visit data (discrete data) were added to the hydrograph and are now visible alongside instrumented data. This new view allows users to better understand long-term trends and conditions at sites over the entire period of observation, not just since the site has been instrumented. In addition to adding the field visit points to the hydrograph, the field visit data was added to the data tables:

Screenshot of a data table on the monitoring location page, with data for groundwater levels

Field visit data section showing groundwater level data

Data shown in hydrographs are now easily accessible in the data download section:

Screenshot of the download data section, showing links to download data

Download section showing field visit data access options

Locations that only have field visits have the data displayed on hydrographs. This improvement makes our interactive hydrographs accessible at many more sites nation-wide, and allows users to visualize the full period of record at sites that are not instrumented and contextualize recent measurements.

Screenshot of a hydrograph that only shows groundwater levels as red dots

Hydrograph for 01N 29E 08BCD1 USGS 125, a well in Butte County, ID with only field visit data

Groundwater field visit data are collected when staff visit wells, boreholes, piezometers, or springs and measure the water-level of the groundwater at that site. USGS and other scientific organizations have been collecting groundwater level data for decades in this manner. This longer period of record that is available by viewing both instrumented and field visit data is now represented by the period of record snapshot on monitoring location pages.

Picture of a person in the grass kneeling over a circular concrete wellhead, with instruments in the background

Student hydrologist Todd Anderson assisting with water measurements and purging of a well at a research location at Ellsworth Air Force Base in South Dakota. The resulting measurement is field visit data. Photo Credit: Kathy Durham.