Water Resources of Pennsylvania
Analytical results for arsenic in water samples from 5,023 wells obtained during 1969–2007 across Pennsylvania were compiled and related to other associated groundwater-quality and environmental factors and used to predict the probability of elevated arsenic concentrations, defined as greater than or equal to 4.0 micrograms per liter (µg/L), in groundwater. Arsenic concentrations of 4.0 µg/L or greater (elevated concentrations) were detected in 18 percent of samples across Pennsylvania; 8 percent of samples had concentrations that equaled or exceeded the U.S. Environmental Protection Agency's drinking-water maximum contaminant level of 10.0 µg/L. The highest arsenic concentration was 490.0 µg/L.
- Estimate baseline streamflow (minimally altered by regulation, diversion, or mining, and other anthropogenic activities) for ungaged streams in Pennsylvania
- Generate text file of daily mean streamflow for the ungaged site for the period 1960 to 2008
- Create a report that includes streamflow data, exceedance probabilities, basin characteristics, and hydrographs for the ungaged site
Baseline Streamflow Estimator (BaSE)
Estimate baseline streamflow for ungaged streams in Pennsylvania
Delineate watersheds and estimate streamflow
- NWIS Mapper
View the locations of sites with USGS water data
Compare current streamflow to historical record
View stream-temperature and water-quality monitoring data
- Groundwater Watch
Compare current groundwater levels to historical record
- Groundwater Recharge
Compare aquifer recharge for 197 watersheds
Get condition updates by text message or email
The USGS Pennsylvania Water Science Center is your direct link to all kinds of water-resource information. Data collection and interpretive studies are done in cooperation with various local, State, and Federal agencies.
Streamflow, lake, reservoir, and precipitation data
Water levels in wells and other aquifer data
Chemical and biological quality data for surface water and groundwater
- Instant Bacteria Forecasts Make Swimmers at Great Lakes Beaches Safer (Thu, 21 Nov 2013 12:48:25 EDT)
- Measuring Landscape Disturbance of Gas Exploration in Four More Pennsylvania Counties: (Thu, 21 Nov 2013 10:23:40 EDT)
- Media Advisory: Upper Delaware River Basin Listening Sessions (Mon, 30 Sep 2013 9:52:52 EDT)
- Measuring Landscape Disturbance of Gas Exploration in Four Pennsylvania Counties (Wed, 18 Sep 2013 12:06:07 EDT)
- Tsunami on the Delaware River? Study of Historical Quake and Early East Coast Seismicity (Tue, 3 Sep 2013 15:00:00 EDT)
On-demand, current conditions for water data directly to your mobile phone or email. 2 ways to get started:
- Send a text message to WaterNow@usgs.gov containing the USGS Site Number of the gage you want to query
- Send an email message to WaterNow@usgs.gov where either the Subject or the first line of the message contains the USGS Site Number of the gage you want to query
Just What Is a 100-Year Flood Anyway?
Almost everyone has heard the term "100-year flood", but not everyone knows what it really means. A common question is, "we just had a 100-year flood a few years ago, why are we having another one so soon?" The USGS Office of Surface Water has released a poster that explains the concept, probabilistic nature, and inherent uncertainties of a 100-year flood. The poster, entitled "100-Year Flood—It's All About Chance," can be found at http://pubs.usgs.gov/gip/106/.