1. Assessment of Low-Flow Characteristics of the Mississippi River Dave Lorenz USGS Water Science Center of Minnesota Research supported by the Met Council

2. Study Objective Characterize the regional low flows in the Mississippi River above Anoka.

3. Approach, Part 1 Low-flow duration statistics will be computed for the Miss. R. near Anoka, one upstream site (Grand Rapids), and three tributaries (Crow R., Crow Wing R., and Rum R.) as well as the headwaters reservoirs. The basins were selected to represent broad subregions in the Miss. R. basin above Anoka.

4. Approach, Part 1, continued

5. The lowest flows in the four subbasins will be examined to assess the likelihood of wide-spread drought compared to more localized droughts. The statistics of the capacity of the headwaters reservoirs will be computed for the lowest flows in the Miss. R. near Anoka.

6. Approach, Part 2 Synthetic flows will be computed by superimposing observed summer flows on observed snowmelt flows.

7. Approach, Part 2, continued

8. Approach, Part 2 This analysis could provide the equivalent of 5,625 years of syntheitc flow values. An estimate of the statistics of the lowest summer flows will be computed from the synthetic flows. All of this is contingent upon consistent management of the reservoirs, observed behaviors of aquifers supplying water at low flow, and consistent climate patterns.