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• Regional Ground-Water Studies
  • Ground-Water Availability in the United States
• Water Availability Pilot
  • Consumptive water use coefficients for Great Lakes Basin
• Ground Water & the Environment
  • Ground-Water Recharge in Southwestern US
• Methods & Modeling
  • SEAWAT v4--Simulation of 3D variable-density ground--water flow and transport
• Data & Information
  • Water-Level changes in aquifers of the Atlantic Coastal Plain, predevelopment to 2000

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Recession-Curve Displacement Method for Estimating Ground-Water 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).

Manual Application

• 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 ground-water 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 ground-water 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 ground-water 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 ground-water 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 ground water to regional aquifers.

• Delin and others (2007) -- Estimates of ground-water 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) -- Estimates of ground-water 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.