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Technical Announcement: USGS Issues Revised Framework for Hydrogeology of Floridan Aquifer
Press Release: High Plains Aquifer Groundwater Levels Continue to Decline
Regional Groundwater Availability Study Geospatial Data
Press Release: USGS Assesses Current Groundwater-Quality Conditions in the Williston Basin Oil Production Area
HydroClimATe -- Hydrologic and Climatic Analysis Toolkit
National Brackish Groundwater Assessment
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Recession-Curve Displacement Method for Estimating Groundwater Recharge In Humid Regions
Case Studies Using the Recession-Curve Displacement Method
RORA has been used to estimate recharge for a number of studies of local to regional scope. Regional-scale applications are shown in Rutledge and Mesko (1996), Flynn and Tasker (2004), Risser and others (2005a), and Dumochelle and Schiefer (2002). Comparisons to other recharge methods were conducted by Coes and others (2007), Delin and others (2007), Risser and others (2005b), Ruhl and others (2002), and Mau and Winter (1997).
- Bevans (1986) – Contains good explanation of theory and detailed description of the steps required for manual application of the recession-curve displacement method.
Regional-Scale Applications of RORA
- Rutledge and Mesko (1996) – Original application of RORA program to estimate recharge for 157 streamflow-gaging stations in the Piedmont, Valley and Ridge, and Blue Ridge Physiographic Provinces, USA.
- Flynn and Tasker (2004) – RORA was used to estimate seasonal and mean-annual groundwater recharge for 55 drainage basins in New Hampshire, USA. Regression equations were developed to relate recharge to basin characteristics.
- Risser and others (2005a) – RORA was used to estimate long-term mean monthly and annual groundwater recharge for 197 basins in Pennsylvania, USA. Results can be compared to those from a base-flow separation technique, with a web interface.
- Dumochelle and Schiefer (2002) – RORA is used to estimate long-term mean-annual groundwater recharge for 161 basins in Ohio and related to basin characteristics. Results can be compared to those from the base-flow-- separation technique PART.
Comparisons of RORA to Other Methods
- Coes and others (2007) – Estimates of groundwater recharge from RORA were compared to estimates from age dating, water-table fluctuation method, and Darcy-Flux method for the Coastal Plain of North Carolina, USA. They found that RORA estimates were low, probably because of underflow of groundwater to regional aquifers.
- Delin and others (2007) [2MB PDF] – Estimates of groundwater recharge from RORA are compared to estimates from age dating, zero-flux plane, and water-table fluctuation methods in Minnesota, USA. They found that RORA estimates agreed well with other methods.
- Risser and others (2005b) – Estimates of recharge from RORA were compared to estimates from zero-tension lysimeters, water-budget calculations, base flow, and the water-table fluctuation methods at a small watershed in Pennsylvania, USA. They found that RORA results were significantly greater than estimates from the other methods.
- Ruhl and others (2002) [1.7MB PDF] – Estimates of groundwater recharge from RORA were compared to estimates from age dating, water budget, and water-table fluctuation methods in the vicinity of Minneapolis-St. Paul, Minnesota, USA. Variability among the methods was large.
- Mau and Winter (1997) – Estimates of recharge from RORA are compared to manual application of the recession-curve displacement method and two base-flow separation techniques. Results showed the sensitivity of RORA to the requirement of antecedent recession.