Abstract

Improved Flow Estimates and QA in NHDPlus Version 2
Track: Water Resources
Authors: Timothy Bondelid

NHDPlus is a set of geospatial products based on the 1:100,000 National Hydrography Dataset. A primary driver in the development of NHDPlus is to provide streamflow estimates for every segment in the surface water network. Stream flow estimates are especially needed to support the surface water missions of USEPA and USGS. The streamflow estimation methods used in NHDPlus Version 2 and the associated QA module provide both improved flow estimates and statistical measures of the accuracy of the estimates. The streamflow estimates rely heavily on geo-spatial analysis. For example, critical inputs to the estimation algorithms include overlays of NHDPlus catchments on runoff, temperature and precipitation grids. An overview of the flow estimation method and the QA results will be presented, with suggestions for "next steps in improving the flow estimates.