What does usgs use to record water level

USGS Current Water Data for the Nation

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Daily Streamflow Conditions

Explanation
High
> 90th percentile
76th - 90th percentile
25th - 75th percentile
10th - 24th percentile
< 10th percentile
Low
Not ranked

The colored dots on this map depict streamflow conditions as a percentile, which is computed from the period of record for the current day of the year. Only stations with at least 30 years of record are used.

The gray circles indicate other stations that were not ranked in percentiles either because they have fewer than 30 years of record or because they report parameters other than streamflow. Some stations, for example, measure stage only.

Select a state from the map to access real-time data

Current data typically are recorded at 15- to 60-minute intervals, stored onsite, and then transmitted to USGS offices every 1 to 4 hours, depending on the data relay technique used. Recording and transmission times may be more frequent during critical events. Data from current sites are relayed to USGS offices via satellite, telephone, and/or radio telemetry and are available for viewing within minutes of arrival.

Build Current Conditions Table Show a custom current conditions summary table for one or more stations.
Build Time Series Show custom graphs or tables for a series of recent data for one or more stations.