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Lori A Sprague

Program Manager, Integrated Water Availability Assessments

Office of the Associate Director for Water

Office Phone: 303-236-6921
Fax: 303-236-5448
ORCID: 0000-0003-2832-6662

DFC Bldg 53
Denver Federal Center
Box 25046
Lakewood , CO 80225-0046

Supervisor: Robert L Joseph
Nonstationary streamflow due to environmental and human-induced causes can affect water quality over time, yet these effects are poorly accounted for in water-quality trend models. This data release provides instream water-quality trends and estimates of two components of change, for sites across the Nation previously presented in Oelsner et al. (2017). We used previously calibrated Weighted Regressions on Time, Discharge, and Season (WRTDS) models published in De Cicco et al. (2017) to estimate instream water-quality trends and associated uncertainties with the generalized flow normalization procedure available in EGRET version 3.0 (Hirsch et al., 2018a) and EGRETci version 2.0 (Hirsch et al., 2018b). The procedure...
This product consists of two tabular datasets and associated metadata for major phosphorus fluxes including manure and fertilizer inputs, crop uptake, as well as waste water treatment facility effluent and river export. These are time series data representing water years 1992 to 2012 for watersheds associated with the National Water Quality Program Surface Water Trends project. Dataset 1: Major fluxes and estimated net P balances. Dataset 2: Results of a t-test to determine if site level mean agricultural P balances were significantly above, not different, or below zero. Each site was then assigned to an Accumulation, Equilibrium, or Depletion status categories, respectively. Identification of sites where river...
he National Water-Quality Assessment (NAWQA) Project provides an understanding of water-quality conditions; whether conditions are getting better or worse over time; and how natural features and human activities affect those conditions. Regional and national assessments are possible because of a consistent study design and uniform methods of data collection and analysis. Monitoring data are integrated with geographic information on hydrological characteristics, land use, and other landscape features in models to extend water-quality understanding to unmonitored areas. Local, State, Tribal, and national stakeholders use NAWQA information to design and implement strategies for managing, protecting, and monitoring...
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