The Hydrologic Engineering Center (HEC), an organization within the Institute for Water Resources, is the designated Center of Expertise for the U.S. Army Corps of Engineers in the technical areas of surface and groundwater hydrology, river hydraulics and sediment transport, hydrologic statistics...Read more

A part of the USGS Water Science School, this page provides a series of questions and answers surrounding water. Topics include Water at Home, Water Use, Measuring Water, Water Chemistry and Quality, and the Water Around Us.Read more

Research paper testing the accuracy of an invasive aquatic plant risk assessment system in the United States, modified from a system originally developed by New Zealand's Biosecurity Program. The high accuracy with which these methods can distinguish non-invaders from harmful invaders suggests...Read more

Taken together, the chapters suggest that although Philadelphia's parcel-based fee system is a good first step toward drawing private investment to green infrastructure, many economic barriers remain. In the current market environment, the discounted payback periods of most green...Read more