using GIS for measuring floodplain losses, associated with water withdrawals, was presented and

discussed.

 The temporal loss of habitat measure is intended to provide protection of the riverine

ecosystems by limiting the reduction in the number of days of connection between the river and

the floodplain. Research showed that the relationship between the flow and the percent-of-flow

reductions required to generate a 15% decrease in the number of days a certain flow is reached

annually is similar for all three rivers studied. The similarity among rivers is highlighted when

flows are plotted in terms of flow per watershed area.

 This research also utilized an alternative approach to determining habitat loss by

employing a spatial measure of habitat, derived from the HEC-RAS model. This method

summed the lengths of inundation along each cross-section in the hydraulic model as a proxy of

area of inundation. This was done because it was important to examine if different measures of

habitat relate differently to changes in flow. Further, if they did respond differently to changes in

flow, it was necessary to characterize which measure would be limiting in terms of flow

reduction if a 15% loss of habitat criteria was applied. The reductions in flow required to

generate a 15% loss of inundated width were calculated and the results for different flows per

watershed area for all three rivers were plotted.

 Calculations were preformed to relate habitat types to specific periods of inundation.

Wetland characteristics were examined and the amount of flow reduction that would result in a

15% loss of inundation was determined. The results for each wetland characteristic among the

cross-sections of a specific river varied widely. Vegetative cross-sections were selected based on

location of shoals within the river and vegetation communities. Cross-sections were selected

which were characteristic of the river corridor. However, as it became evident that it was