Delaware River Basin NAWQA Study
DELAWARE RIVER BASIN NAWQA WORKPLAN
USGS IN YOUR STATE
USGS Water Science Centers are located in each state.
Workplans on Study Design—May 1999
NAWQA ecological studies are used to evaluate the effects of physical, chemical, and habitat characteristics on biological communities. Ecological surveys are done along a delineated stream reach and include a habitat assessment of the site and annual surveys of the fish, algal, and benthic invertebrate communities.
Fixed-site ecological assessment
Ecological assessments will be conducted at all fixed sites, and a subset of synoptic sites, as part of the Delaware NAWQA study. All ecological components will be conducted at wadable indicator sites, and a subset of components will be conducted at large river sites (this includes the Delaware at Port Jervis, the Lehigh at Easton, the Delaware at Trenton, and the Schuylkill at Philadelphia). The following will be collected at all wadable indicator sites (1) benthic invertebrate richest targeted habitat (RTH) samples and qualitative multihabitat samples (QMH), (2) periphyton RTH, QMH, and depositional targeted habitat (DTH) samples, (3) fish-community samples, (4) habitat levels I and II. In addition, we plan to collect periphyton samples for chlorophyll A, B, and AFDM. (Sample table)
Schedule of Fixed-site ecological assessments 1999-2001
Fixed site sampling - Single-reach sampling is planned for 1999 at all indicator sites, and FY1999 or FY 2000 at integrator sites. (schedule). Multiple-year sampling for select components is planned for all indicator sites in 1999, 2000, 2001. Multiple-year sampling will provide data on temporal variations in populations and avoid limiting data collection to a single year that might have unusual hydrologic conditions. One or two of the multiple year sites will be selected as intensive ecological assessment sites at which multiple reach sampling will be conducted from June through September 2001.
Invertebrate and algae sampling - Invertebrate and algae sampling (I&A) is planned for June and July because (1) site conditions should be near base flow and most sites will be accessible, (2) invertebrate and algae samples can be collected before the site is disturbed for fish-community sampling, and (3) August and September would be left available for fish-community sampling. Invertebrate and algae sampling during June and July overlaps with the invertebrate and algae collection period of most neighboring NAWQA study units in the Northeast Region. Benthic invertebrate collection by other agencies in the Delaware River basin occurs during a variety of months, depending on objectives and logistical issues faced by each agency.
Habitat - Habitat level I will be done during June and July on the same day as invertebrate and algae community sampling at each site. Habitat level II (surveyed cross-sections) is planned for FY 1999, FY 2000, and (or) FY 2001. Some of the Habitat level II work (e.g. Wolman pebble counts) might be incorporated into the habitat level I work being done during June-July each year. The surveyed cross-section work will be spread out over the 3 years, depending on how many sites are to be surveyed.
Fish-community surveys - Fish-community surveys will be conducted between August and September 1999, and/or 2000, or 2001 at all indicator sites. A decision will be made after field reconnaissance and continuing retrospective analysis regarding whether or not to conduct fish community surveys at integrator sites. This will depend on (1) site conditions, (2) resources required, and (3) the availability of existing recent fish-community data for the site. If fish community surveys are conducted at integrator sites, they will be scheduled during FY 2000 or FY 2001.
Ecological synoptic assessments
Ecological synoptics will be coordinated with our proposed urban water quality synoptic. Ecological surveys will be conducted at all synoptic sites during low-flow conditions. Ecological components would be a subset of those collected at fixed sites, and would probably include periphyton, habitat, and benthic invertebrates. We would like to include fish-community surveys at some sites, and might be able to link with other agencies or organizations to have some of this work done as a joint effort.