Virginia’s Department of Environmental Quality (DEQ) Office of Wetland and Stream Protection, in collaboration with the Virginia Institute of Marine Science, has developed a wetland monitoring and assessment protocol to provide an ongoing assessment of the status of the Commonwealth’s wetland resources and the success of both wetland regulatory and voluntary programs.
The assessment protocol consists of a three-tiered approach using comprehensive coverage of all mapped non-tidal wetlands to achieve a GIS based analysis of remotely sensed information (Level I). Level I scores wetland types based on the habitat and water quality stressors associated with surrounding land use types. Levels II and III are intended to calibrate and validate the model that is used for Level I analysis. By having a statistically validated tool that measures wetland quality as a function of habitat and water quality parameters, DEQ permit staff will be able to make better permit decisions. Further, DEQ will be able to measure how well we are protecting the function of our more vulnerable wetlands (i.e., isolated wetlands), by comparing the condition of wetland habitat and water quality parameters as a function of the assessment scoring over time.
Results to Date:
The data collected from the assessment have been compiled into an online GIS-based wetland data viewer identified as the Wetland Condition Assessment Tool (WetCAT). One unique aspect of WetCAT is its online interactive user interface, which allows users to overlay data such as previously permitted impacts and impaired waters and run various geoprocessing tools to visualize cumulative impacts, downstream flow, and upgradient drainage areas.
The goal of WetCAT is to support DEQ’s regulatory decision-making, allow reporting of wetland condition, and provide information for policy development. In particular, information derived from monitoring will be used to:
- Report ambient wetland conditions in Virginia’s Clean Water Act Integrated 305(b)/303(d) report;
- Evaluate wetland impacts from proposed projects within a watershed context during permit review as part of Virginia’s regulatory program;
- Evaluate the performance of wetland restoration and other compensatory wetland mitigation in replacing wetland acreage and function, including changes in wetland condition over time based upon surrounding landscape changes and maturity of the mitigation site; and
- Evaluate the cumulative impacts of wetland loss and restoration in watersheds relative to ambient ecological conditions and water quality management needs.
One of the advantages of the Virginia protocol is a comprehensive assessment of secondary impacts to wetland resources arising from activities that do not directly impact wetlands. This information can guide policy discussions on general land use management, stormwater, and land use planning. Linking decisions in these areas to wetland policy will be essential to achieving our statutory requirement of no net loss of wetland acreage and function, and aid local governments with planning tools at a watershed level.
Additional data sets and GIS layers will allow Virginia to continue to develop a wetland data viewer for use by regulatory agencies and the general public. Our success will be measured by an increasing trend in the statistically-reliable Level I protocol and a decreasing trend in cumulative wetland impacts over time.
David L. Davis, CPWD, PWS
Director, Office of Wetlands & Stream Protection
Michelle M. Henicheck, PWS
Senior Wetland Ecologist