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Resources: York River Water Budget - Management Recommendations
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 Modification of coastal river hydrographs will impact tidal freshwater systems.
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Natural flow variations may be a critical factor in the capacity of tidal freshwater systems to perform many highly valued functions.
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Absent more certain knowledge of flow modification impacts, a precautionary management strategy that seeks to preserve the general shape of a river’s hydrograph is preferred.
Since estuaries function with complex interactions, we suggest that simply maintaining the average hydrograph is insufficient for estuarine systems. A combined biological and geological approach to water withdrawal management would be more appropriate for the York River Estuary. Much needed data for development of a comprehensive management based on biological and geological functions is lacking.
Therefore, the following management recommendations are proposed:
1. Maintain the timing and flow of peak flow events when permitting ground and surface water withdrawals while maintaining a natural hydrograph. Past permitted withdrawls need to be considered during analysis of current hydrograph data. The maintenance of the timing (seasonally) of peak flow events may be particularly important because certain biological functions such as diatom blooms or larval fish movement may be dependent on peak flow events occurring within a particular window. In the Pamunkey it may be important to maintain peak flow events in August as well as in the early spring due to variations in flow.
2. Begin baseline monitoring of biological and geological characteristics before more withdrawals are permitted. These should include: marsh vegetation extent and distribution of species; submerged aquatic vegetation extent and distribution of species; anadromous fish species distribution and movement; sediment erosion and deposition in marshes; and sediment erosion and deposition on beaches.
3. Require biological monitoring as part of any surface or groundwater withdrawal permits to establish a baseline and provide early evidence of changes in ecological systems.
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