Analysis of Hydrologic Data for the White River Basin

The value of the natural resources of the White River Basin (Basin), AR isrecognized by the area's designation as a "Wetland of International Importance". TheBasin constitutes one of the Nation's largest remaining intact forested wetlandlandscapes, second only to the Atchafalya Basin. It supports the North Americancontinent's largest concentration of over-wintering mallard ducks, a world-class troutfishery, the last vestige of a big river fishery remaining in the Mississippi River Basin,and numerous threatened and endangered species. The continued viability of thiswetland ecosystem depends on the suitability of the hydrologic environment to theresident flora and fauna. Numerous modifications of the Basin hydrologic features in thepast century have seriously impaired the sustainability of these resources. The Basinwidealterations of hydrologic processes (e.g., impoundment and regulatory releases offlows and volumes in the upper reaches, navigational modifications of lower reaches, andconsumptive demands for agricultural use throughout) have affected the hydrology of thesystem profoundly. The result is highly regulated flows and stages, vastly alteredhydrologic patterns, over-stabilized water levels, and disruption of seasonal waterdistribution patterns. Given the critical nature of hydrology in regulating the structureand function of wetland ecosystems, the impacts have been devastating, particularly tothe critical bottomland hardwoods that support the Basin's fish and wildlife resources.To date these piece-meal, system-wide, hydrologic alterations have cornmutativelydegraded the habitat value of this resource for fish and wildlife in the Basin, and havelead to changes in their numbers and distributions. In spite of the enormous stakesinvolved, there has been no comprehensive characterization of the Basin hydrology.System alterations such as channel deepening, dam construction, water allocationplans, and flood control measures are currently pending. These projects will potentiallyhrther modify the hydrologic environments of the Basin, and no doubt require mitigationmeasures. In addition, there is genuine interest in restoring aspects of the Basin's historichydrologic regime within some set of reasonable limits. In order to proceed with thiseffort, the anticipated effects of these modifications and restorations on the Basin ecologyrequire thorough study of the area's historic hydrology, so that connectivity among Basinprecipitation patterns, flow fluctuations, and land use changes can be made. A basinhydrologic characterization is an initial component of this effort. The focus of this effortwas to determine and assemble the data set from which characterization of the hydrologicenvironments of the Basin using historic and recent water level, flow, (primarily byUSGS-WRD) at locations throughout the Basin could proceed. ( Document has 11 pages.)

Research Work Order no. 203