Impact/Purpose:

To field test and apply newly developed bioassessment protocols for use on New Jersey lakes. Results of studies will be used to make recommendations to NJDEP for a statewide lakes monitoring program.

Description:

Federal and State agencies routinely monitor waterbodies for various chemical, physical and biological parameters. One of the stated goals of the Clean Water Act is to maintain and restore the chemical, physical and biological integrity of the nation's surface waters. Unfortunately, there is considerable debate regarding the present ability of monitoring programs to document water quality improvements or declines on regional and national scales. In response to this concern, a number of recommendations have been made to enhance surface water quality monitoring, including the development of promising biological techniques. With these recommendations and a renewed interest in biological assessments, the EPA developed technical guidance on bioassessment protocols for use on streams and rivers, lakes and reservoirs, and estuaries and coastal marine waters. Before the protocols can be applied for monitoring, they must be assessed for their technical soundness, general usefulness, and cost effectiveness. In addition the protocols may require some modification to account for geographic variation in aquatic communities. Results of the validation studies will be used to improve biological monitoring in lakes. Several phases (sediment diatoms, sublittoral macroinvertebrate and littoral macroinvertebrate) have been completed. In the summer of 2007 a study is being conducted to field validate a lake macroinvertebrate integrity index (LMII). The index requires the use sublittoral macroinvertebrate data. In order to measure the effectiveness of the index at distinguishing reference from degraded lakes, verification with an independent data set was needed. Lastly, the development of the LMII was limited in scope to northern New Jersey lakes and requires additional verification for its applicability in broader regions of the Mid-Atlantic and Northeast. Preliminary analysis of the lake fish data collected 2002-2006 indicates greater sunfish species and overall species richness at reference verses impaired lakes, and greater % tolerant species at impaired verses reference lakes. Two additional years of study will be required to understand how natural factors such as lake size, position in the drainage, and lake alkalinity influence fish communities.

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