USGS - science for a changing world

USGS Groundwater Information

Groundwater Resources Program

*  Home *  Regional GW Studies *  GW & Environment * Methods & Modeling *  Publications *  Data & Information [an error occurred while processing this directive] *  Intranet
 [Photo: Groundwater flowing out of well.]

New & Noteworthy

* Press Release: Study Explores Groundwater and Geothermal Energy in Drought-Stricken Eastern Oregon and Neighboring States

* 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

Past listings...

USGS Groundwater Watch

USGS maintains a network of active wells to provide basic statistics about groundwater levels.

 [Image: USGS active water level wells location map.]

Other Water Topics

*  Water Resources

*  Groundwater

*  Surface Water

*  Water Quality

*  Water Use

USGS in Your State

USGS Water Science Centers are located in each state.

 [Map: There is a USGS Water Science Center office in each State.] Washington Oregon California Idaho Nevada Montana Wyoming Utah Colorado Arizona New Mexico North Dakota South Dakota Nebraska Kansas Oklahoma Texas Minnesota Iowa Missouri Arkansas Louisiana Wisconsin Illinois Mississippi Michigan Indiana Ohio Kentucky Tennessee Alabama Pennsylvania West Virginia Georgia Florida Caribbean Alaska Hawaii and Pacific Islands New York Vermont New Hampshire Maine Massachusetts South Carolina North Carolina Rhode Island Virginia Connecticut New Jersey Maryland-Delaware-D.C.

Recession-Curve Displacement Method for Estimating Groundwater Recharge In Humid Regions

Manual Determination of K

The recession index can be determined by manual compilation of a master recession curve composed of numerous recession segments during periods when groundwater was the dominant component of flow for each streamflow-gaging station. An example of manual construction of a master recession curve is shown in the figure from Bevans (1986). The extrapolated base-flow recession on the semi-log plot defines a straight line that declines one log cycle in 32 days. Thus, recession index is 32 days for this watershed.

determination of the slope of the base-flow recession curve
Determination of the slope of the base-flow recession curve (from Bevans, 1986).

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://water.usgs.gov/ogw/gwrp/methods/recession_curve/manual_k.html
Page Contact Information: Contact the Groundwater Resources Program
Page Last Modified: Tuesday, 03-Jan-2017 20:46:34 EST