![]() Your state government probably maintains a database of drillers' logs that have water levels recorded when a well was drilled, and hydrologic consultants often have reports that contain water level data from shallow boreholes.Ĭonsulting any or all of these sources is a good first step in finding out the depth to the water table.Use their Data Portal to zoom in to your area of interest and click on any site. The National Groundwater Monitoring Network is a compilation of groundwater monitoring wells from federal, state, and local groundwater networks across the nation.Click on any red groundwater pin to access the data (need to zoom in to change the dots to pins). A convenient way to find data for your area is by using the NWIS Mapper and selecting "Groundwater Sites" in the menu on the left. ![]() The USGS National Water Information System (NWIS) has depth-to-water measurements made in the present and the past.The most reliable method of obtaining the depth to the water table at any given time is to measure the water level in a shallow well with a tape. If no wells are available, surface geophysical methods can sometimes be used, depending on surface accessibility for placing electric or acoustic probes.ĭatabases containing depth-to-water measurements can also be helpful, though they don't always have current data: Theyre also known as Water Depth Markers, Water Flow Gauges, Flow Meters, Staff Gauges, or Water Depth Gages. The staff gauges are the wooden posts on which enamelled metal plates graduated to 0.01 m are fixed. Staff Gauges: It is a simple device used to record the water level. When water-loving plants start to grow again in the spring and precipitation gives way to hot, dry summers, the water table falls because of evapotranspiration. Stream Gauges are the best permanent markers for measuring water depths of rivers, streams, lakes, ponds, and swamps. The two commonly adopted methods of recording water levels are: ADVERTISEMENTS: 1. During the late winter and spring when accumulated snow starts to melt and spring rainfall is plentiful, water on the surface infiltrates into the ground and the water table rises. They have zero-position memory, also known as absolute (ABS) positioning, which retains the measuring position when the gauge is turned off. All are IP67 rated for protection from dust and temporary water submersion. ![]() The depth to the water table can change (rise or fall) depending on the time of year. These gauges come with a calibration certificate traceable to NIST that states theyve passed a test for accuracy. Well Depth Measurement Tools, Devices, Procedures Trimmer (1991) describes three methods to measure water levels in a well: an electronic sounder or depth gauge (device lowered on wire senses distance to water top), a wetted tape (accurate to about 90 ft), and an air line (measures anticipated usage volume not actual well water depth).
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