By

Vogel, Richard M1

1Tufts University, Department of Civil and Environmental Engineering

A general introduction to the new field of ‘hydromorphology’ will be given. Hydromorphology is to hydrology, as geomorphology is to geology. Hydromorphology deals with the evolution and structure of systems. There are very few water systems which are not subjected to anthropogenic influences such as land use, water use and climate change. Hydromorphology deals with the challenges of sorting out the impacts of these various anthropogenic influences on the hydrologic cycle.

Water availability for both human and ecosystem needs is projected to be a critical national and global challenge in the 21st century. Water availability for human and ecosystem needs is confounded by agricultural irrigation, land use modifications, climate change and the depletion and pollution which results from human withdrawals and return flows from rivers as well as aquifer depletion. New challenges have been issued for a regular and systematic assessment of water resources at national and global scales. In the United States, Congress asked the U.S. Geological Survey to outline an approach for a national assessment of water availability and use, and the White House Office of Science and Technology Policy has recently called for a “national water census”. Interestingly, the last national water census was performed over 35 years ago and in the interim an explosion in computer technology, spatially distributed database management systems and anthropogenic change leads one to ask numerous questions relating to how such a national water census should proceed. A generalized approach to performing a national water census based primarily on readily available climatic, hydrologic, land-use, water-use and other demographic data will be described. The approach will be applied to a number of regions within the U.S. over a wide range of spatial and temporal scales. The approach involves a number of innovations including: the development of new indicators of water stress, definition of water management units, choice of the correct spatial and temporal scale for assessing water stress and the management of green and blue water sources.