Statewide Rotating Basin Monitoring Program

Oklahoma is committed to systematically identifying waters impaired by nonpoint source pollution. The Water Quality Division has developed a strategy to monitor small feeder streams on a rotational basis to determine the impacts of non-point source pollution on the water resources of the state. Through the Rotating Basin Monitoring Program, chemical, physical, and biological sampling is done on 250 priority streams in five watershed basins across the state. Each year monitoring begins in one basin, where streams are monitored for two years. Using this rotation, all basins and 250 streams are monitored every five years, and then the rotation begins again. Monitoring is used to:

  • Determine the beneficial use status of streams
  • Collect information on sources of pollution
  • Evaluate success of past and current restoration projects
  • Gather data for planning and implementing future projects

Fixed Monitoring Sites

Group 1
Upper Canadian
Group 2
Upper North Canadian
Upper Arkansas
Group 3
Lower North Canadian
Lower Canadian
Lower Arkansas
Group 4
Upper Red
Group 5
Lower Red
2001-2002 Report2002-2003 Report2003-2004 Report2004-2005 Report2005-2006 Report
2006-2007 Report2007-2008 Report2008-2009 Report2009-2010 Report2010-2011 Report
2011-2012 Report2012-2013 Report2013-2014 Report2014-2015 Report2015-2016 Report
2016-2017 Report2017-2018 Report2018-2019 Report2019-2020 Report

Probabilistic Monitoring Sites

Monitoring randomly selected sites in a basin allows for a statistical statement about the quality of all waters inside the sampled watersheds. To conduct this probabilistic sampling, EPA staff from the Corvalis Lab randomly select for the Commission 150 sites within the basin where sampling will occur the following year. Access permissions are obtained from abutting landowners according to the order of sites listed until a total of fifty sites permissions are obtained. EPA scientists have determined a minimum of fifty sites is necessary to achieve statistical confidence necessary. Water sampling is done and the same parameters measured for the rotating basin streams are assessed. Resulting data are used to make statements with statistical confidence regarding the status of all streams (no greater than Strahler order of 6) from the basin sampled. Data from the probabilistic sites is included in the following Rotating Basin reports: Group 3 2008, Group 3 2009, Group 5 2010, Group 1 2011, and Group 2 2012 (still in progress).