The U.S. Geological Survey (USGS), in cooperation with the Federal Emergency Management Agency, Pennsylvania Department of Environmental Protection, Pennsylvania Department of Transportation, and Susquehanna River Basin Commission, prepared hydro-conditioned geographic information systems (GIS) layers for use in the Pennsylvania StreamStats application. These data were used to update the peak flow and low flow regression equations for Pennsylvania. This dataset consists of flow accumulation rasters for each 8-digit Hydrologic Unit Code (HUC) area in Pennsylvania, one of the layer types needed to delineate watersheds within the HUC-8 areas, merged into a single dataset. The 59 HUCs represented by this dataset are 02040101, 02040102, 02040103, 02040104, 02040105, 02040106, 02040201, 02040202, 02040203, 02040205, 02050101, 02050102, 02050103, 02050104, 02050105, 02050106, 02050107, 02050201, 02050202, 02050203, 02050204, 02050205, 02050206, 02050301, 02050302, 02050303, 02050304, 02050305, 02050306, 02060002, 02060003, 02070002, 02070003, 02070004, 02070009, 04110003, 04120101, 04130002, 05010001, 05010002, 05010003, 05010004, 05010005, 05010006, 05010007, 05010008, 05010009, 05020001, 05020002, 05020003, 05020004, 05020005, 05020006, 05030101, 05030102, 05030103, 05030104, 05030105, and 05030106.

The U.S. Geological Survey (USGS), prepared geographic information systems (GIS) layers for use in the West Virginia StreamStats application. The Digital Elevation Model and associated data were hydrologically conditioned, which is the process of burning in single line streams at the 1:24,000 scale into a digital elevation model to produce flow direction and flow accumulation grids. This data includes geotif images for a 10 meter digital elevation model, a flow direction, and a flow accumulation raster/grid image for the WV Streamstats area. The 34 HUCs represented by this dataset are 02070001, 02070002, 02070003, 02070004, 02070005, 02070006, 02070007, 05020001, 05020002,05020003, 05020004, 05020005, 05020006, 05030101, 05030106, 05030201, 05030202, 05030203, 05050001, 05050002, 05050003, 05050004,05050005, 05050006, 05050007, 05050008, 05050009, 05070101, 05070102, 05070201, 05070202, 05070204, 05090101, and 05090102.

The U.S. Geological Survey (USGS), in cooperation with the Federal Emergency Management Agency, Pennsylvania Department of Environmental Protection, Pennsylvania Department of Transportation, and Susquehanna River Basin Commission, prepared hydro-conditioned geographic information systems (GIS) layers for use in the Pennsylvania StreamStats application. These data were used to update the peak flow and low flow regression equations for Pennsylvania. This dataset consists of stream definition 900 cell threshold rasters for each 8-digit Hydrologic Unit Code (HUC) area in Pennsylvania, one of the layer types needed to delineate watersheds within the HUC-8 areas, merged into a single dataset. The 59 HUCs represented by this dataset are 02040101, 02040102, 02040103, 02040104, 02040105, 02040106, 02040201, 02040202, 02040203, 02040205, 02050101, 02050102, 02050103, 02050104, 02050105, 02050106, 02050107, 02050201, 02050202, 02050203, 02050204, 02050205, 02050206, 02050301, 02050302, 02050303, 02050304, 02050305, 02050306, 02060002, 02060003, 02070002, 02070003, 02070004, 02070009, 04110003, 04120101, 04130002, 05010001, 05010002, 05010003, 05010004, 05010005, 05010006, 05010007, 05010008, 05010009, 05020001, 05020002, 05020003, 05020004, 05020005, 05020006, 05030101, 05030102, 05030103, 05030104, 05030105, and 05030106.

The U.S. Geological Survey (USGS) in cooperation with the Pennsylvania Department of Conservation and Natural Resources (PA DCNR), Bureau of Geological Survey, provides time series trends results using the Mann Kendall family of analyses on select sites across Pennsylvania for baseflow, runoff, groundwater levels, and streamflow percentiles.

Streamflow was collected at various streamgages in western Pennsylvania in support of the scientific investigations report "Estimation of Base Flow on Ungaged, Periodically Measured Streams in Small Watersheds in Western Pennsylvania". Data observed at the streamgages for the period of August 1, 2014 through March 31, 2017 are considered. This dataset includes 1) all data used to develop prediction intervals for the titled estimation site based upon the titled index streamgage for the period of May 1, 2015 to March 31, 2017 and 2) evaluation of data observed before May 1, 2015. For prediction interval development, a Move.1 regression was developed between the titled estimation site and titled index streamgage. From this regression model, Pearson's correlation coefficient (r) is reported, and the Nash-Sutcliffe efficiency value is computed. The prediction interval development is included for the 95% prediction interval for both the nonparametric and parametric methods. For the parametric method, any prediction interval can be developed by changing Student's t critical value. Any data that were observed before May 1, 2015 were evaluated to see if they fell within the 95% nonparametric prediction interval. The data chosen for the regression development and evaluation is streamflow that is not influenced by runoff. Streamflow that occurred the day of precipitation and two days after is considered influenced by runoff and not included in the dataset. Not all streamgages have the same period of record; dates where data were observed both at the titled index streamgage and estimation site are described below in the "Time Period of Data" section.

Streamflow was collected at various streamgages in western Pennsylvania in support of the scientific investigations report "Estimation of Base Flow on Ungaged, Periodically Measured Streams in Small Watersheds in Western Pennsylvania". Data observed at the streamgages for the period of August 1, 2014 through March 31, 2017 are considered. This dataset includes 1) all data used to develop prediction intervals for the titled estimation site based upon the titled index streamgage for the period of May 1, 2015 to March 31, 2017 and 2) evaluation of data observed before May 1, 2015. For prediction interval development, a Move.1 regression was developed between the titled estimation site and titled index streamgage. From this regression model, Pearson's correlation coefficient (r) is reported, and the Nash-Sutcliffe efficiency value is computed. The prediction interval development is included for the 95% prediction interval for both the nonparametric and parametric methods. For the parametric method, any prediction interval can be developed by changing Student's t critical value. Any data that were observed before May 1, 2015 were evaluated to see if they fell within the 95% nonparametric prediction interval. The data chosen for the regression development and evaluation is streamflow that is not influenced by runoff. Streamflow that occurred the day of precipitation and two days after is considered influenced by runoff and not included in the dataset. Not all streamgages have the same period of record; dates where data were observed both at the titled index streamgage and estimation site are described below in the "Time Period of Data" section.

Streamflow was collected at various streamgages in western Pennsylvania in support of the scientific investigations report "Estimation of Base Flow on Ungaged, Periodically Measured Streams in Small Watersheds in Western Pennsylvania". Data observed at the streamgages for the period of August 1, 2014 through March 31, 2017 are considered. This dataset includes 1) all data used to develop prediction intervals for the titled estimation site based upon the titled index streamgage for the period of May 1, 2015 to March 31, 2017 and 2) evaluation of data observed before May 1, 2015. For prediction interval development, a Move.1 regression was developed between the titled estimation site and titled index streamgage. From this regression model, Pearson's correlation coefficient (r) is reported, and the Nash-Sutcliffe efficiency value is computed. The prediction interval development is included for the 95% prediction interval for both the nonparametric and parametric methods. For the parametric method, any prediction interval can be developed by changing Student's t critical value. Any data that were observed before May 1, 2015 were evaluated to see if they fell within the 95% nonparametric prediction interval. The data chosen for the regression development and evaluation is streamflow that is not influenced by runoff. Streamflow that occurred the day of precipitation and two days after is considered influenced by runoff and not included in the dataset. Not all streamgages have the same period of record; dates where data were observed both at the titled index streamgage and estimation site are described below in the "Time Period of Data" section.

Streamflow was collected at various streamgages in western Pennsylvania in support of the scientific investigations report "Estimation of Base Flow on Ungaged, Periodically Measured Streams in Small Watersheds in Western Pennsylvania". Data observed at the streamgages for the period of August 1, 2014 through March 31, 2017 are considered. This dataset includes 1) all data used to develop prediction intervals for the titled estimation site based upon the titled index streamgage for the period of May 1, 2015 to March 31, 2017 and 2) evaluation of data observed before May 1, 2015. For prediction interval development, a Move.1 regression was developed between the titled estimation site and titled index streamgage. From this regression model, Pearson's correlation coefficient (r) is reported, and the Nash-Sutcliffe efficiency value is computed. The prediction interval development is included for the 95% prediction interval for both the nonparametric and parametric methods. For the parametric method, any prediction interval can be developed by changing Student's t critical value. Any data that were observed before May 1, 2015 were evaluated to see if they fell within the 95% nonparametric prediction interval. The data chosen for the regression development and evaluation is streamflow that is not influenced by runoff. Streamflow that occurred the day of precipitation and two days after is considered influenced by runoff and not included in the dataset. Not all streamgages have the same period of record; dates where data were observed both at the titled index streamgage and estimation site are described below in the "Time Period of Data" section.