Online annual reports (since 1999) documenting hydrologic data for Pennsylvania gathered from USGS surface water and ground water data-collection networks and information on ordering paper copies of previous years.
Estimates of annual peak-streamflow frequency are needed for flood-plain management, assessment of flood risk, and design of structures, such as roads, bridges, culverts, dams, and levees.
Congress asked us (in the Energy Independence and Security Act of 2007) to figure out how to assess the effects of carbon storage, sequestration, and greenhouse gas fluxes in our ecosystems. Here's how we plan to do that.
Site for a USGS project under the U.S. Global Change Research Program for a national assessment of the impacts of climate variability and change on resources with links to impacts in Alaska, western U.S., public lands, and water resources.
Using ground-water geochemical analyses, and mathematical models, the factors affecting the quality of public water supply were identified as pumping schedule, screened interval, past land use within the recharge area, and natural geochemical conditions.
Using ground-water geochemical analyses and mathematical models, the factors affecting the quality of public water supply were identified as mixing of very recent recharge with older water, karst features, natural geochemical processes, and pumping.
Explains the natural and human-affected factors that determine the concentration of contaminants in groundwater, especially where the concentration is different at the surface than at depth, and where pumping varies with time.