Nontidal Water Quality Monitoring Program

The Chesapeake Bay Program nontidal water quality monitoring program began in 2004 to better estimate nutrient and sediment loadings from the region’s rivers and streams.

The nontidal monitoring network consists of 126 stations throughout the Chesapeake Bay watershed and includes the nine River Input Monitoring stations, representing about 2/3 of the flow above the fall line. Stations are located near USGS stream-flow gages to permit estimates of nutrient and sediment loadings and trends in loadings delivered downstream. Routine samples are collected monthly, and eight additional storm-event samples are collected per year to obtain 20 samples per year, representing a range of discharge and loading conditions.

The Chesapeake Bay Program Integrated Monitoring Networks Workgroup provides inter-agency coordination among the nontidal network participants to ensure the continuity of operations. Sampling is performed by nine agencies in five states, with five laboratories analyzing the samples. Participants follow standard operating procedures that conform to Nontidal Network protocols and quality control specifications, which are based on USGS sampling methods and EPA-approved analytical methods.

The Bay Program Data Integrity Workgroup routinely evaluates laboratory performance through inter-laboratory studies such as the Chesapeake Bay Split Sample and Blind Audit Programs and the USGS Standard Reference Sample Program. Nontidal water quality data are reported to the Bay Program and are available in the Data Hub.

Quality Assurance Project Plans

• Maryland DNR Nontidal Network Program QA Project Plan
• Maryland USGS River Input Monitoring QA Project Plan 
• New York and Pennsylvania (Susquehanna River Basin Commission) Nontidal Monitoring Program QA Project Plan
• Pennsylvania DEP Nontidal Monitoring Network QAPP
• Virginia DEQ Nontidal Monitoring QA Project Plan and SOP
• Virginia USGS River Input Monitoring QA Project Plan
• West Virginia USGS Nontidal Monitoring QA Project Plan
• USGS Kentucky Sediment Laboratory Quality-Assurance Plan for the Analysis of Fluvial Sediment

Related Documents

• USGS National Field Manual for the Collection of Water-Quality Data establishes protocols for the use of science-based, clean sampling procedures. See also: USGS sediment and water quality samplers
• Recommendations to improve coordinated nontidal monitoring, assessment, and communication activities in support of Chesapeake Bay restoration: A report addressing STAC  recommendation for monitoring reallocation
• Potomac River Input Monitoring at Chain Bridge by Metropolitan Washington Council of Governments and Virginia Tech Occoquan Watershed Monitoring Laboratory
• Establishing a Chesapeake Bay Nontidal Watershed Water-Quality Network describes the objectives and rationale for the CBP nontidal monitoring program