New & Noteworthy

 ModelMuse: Graphical User Interface for MODFLOW-2005 and PHAST (TM 6-A29)

 Groundwater: Ground water versus groundwater (OGW Technical Memo 2009.03)

 Field Techniques for Estimating Water Fluxes Between Surface Water and Ground Water (TM 4–D2)

 Ground-Water Availability in the United States (Circular 1323)

USGS in Your State

USGS Water Science Centers are located in each state.

Guidelines for Index Well Selection for the CBR Program

In 1995, the Office of Groundwater began oversight of the groundwater Collection of Basic Record (CBR) Program. A description of the process used to select the initial CBR-funded wells can be found at CBR Program History. In FY2002, public web pages were announced that highlight the CBR wells. In later releases of the web pages, the Climate Response Network was enhanced to include non-CBR wells that met the same criteria. In FY2003, the CBR Program was rolled into the Ground Water Resources Program as a part of the overall USGS budget re-structuring.

Guidelines for Well Selection

These guidelines are to assist in identifying potential index wells to be part of a national, long-term water-level monitoring network. The end product should be a network of index wells where uninterrupted, long-term water-level records are collected. The water-level changes should primarily reflect climatic variability and not human influences. The climate variations of interest are those that affect recharge on monthly and longer time scales; not barometric or tidal influences.

Areas where water-level changes are relatively unaffected by human activity should be delineated on maps of the major aquifers in the District. Maps from the National Ground Water Atlas should be used in order to maintain regional continuity. Observation wells should satisfy the following required minimum criteria:

• Open to a single, known hydrogeologic unit
• Known well construction that allows good water-level measurements
• Located in unconfined aquifers or near-surface confined aquifers that respond to climatic fluctuations
• Minimally affected by pumpage and likely to remain so
• Essentially unaffected by irrigation, canals, and other potential sources of artificial recharge
• Long-term accessibility
• Well has never gone dry (not susceptible to going dry)

Additional desired characteristics:

• Representative of broad area (e.g., a regional aquifer)
• Complete characterization of the site is available
• A long record of water-level measurements exists
• Lithologic and geophysical logs available
• Alternative well identified for each site

Climate Response Network

All CBR network well data are served via the Internet from the Climate Response Network (CRN) web site. Districts are strongly encouraged to include non-CBR wells on the CRN web site if these wells meet CBR criteria. Additional wells can be added by submitting a spreadsheet to Linda Geiger including the following information for each new well. These wells must be configured in NWISWeb prior to inclusion in CRN and the information submitted should match what is shown on NWISWeb. Using the supplied Data Descriptors and Statistics Codes, the Office of Groundwater will retrieve historical daily values data from the local NWIS server and load these data into the CRN database for realtime and non-realtime continuous sites. Water-level data from manually measured sites are retrieved directly from NWISWeb.

Well info needed: (example)

Station numbe     85638077220101 
Station name      52V 2D (should match what is served in NWISWeb)
Latitude          385658 
Longitude         772201
Period Of Record  1976-present 
Aquifer tapped    Manassas Sandstone 
Interval tapped   35-205 
Frequency         Realtime (choices are realtime, continuous, 
                   or number for number of times per year)

If applicable,

Daily Values Period of Record   1995-present
DD                              1
Stat code                       3