(CAZB Home Page | Overview | CAZB Sampling Sites | Synoptics)
The Central Arizona Basins NAWQA surface-water program includes an aquatic biology component.
Bed-sediment and tissue studies assess the presence, concentration, and areal distribution of trace element and hydrophobic organic contaminants in streambed sediment and aquatic tissue.
Ecological studies evaluate the effects of physical and chemical characteristics of water and stream habitat on aquatic biota, and how biological and habitat characteristics differ between NAWQA study units.
Bed-sediment and tissue studies assess occurrence and distribution of trace elements and hydrophobic organic contaminants.
The Occurrence Survey is designed to provide an initial identification of selected constituents from a relatively small number of sites. The highest level of importance is assigned to those constituents found at elevated levels over a wide area or within many small areas. Site selection is designed to maximize the probability of detecting these constituents.
The Spatial Distribution Survey improves geographic coverage for priority constituents through sampling over a broader area.
Ecological studies sites include:
Fixed-Site Reach Assessments that are chosen to provide nationally consistent ecological information at all Basic and Fixed sites as part of an integrated physical, chemical, and biological assessment of water quality,
Intensive Ecological Assessments to assess spatial and temporal of biological communities and habitat characteristics, and
Ecological Synoptic Studies to provide improved spatial resolution of selected ecological characteristics in relation to land uses, contaminant sources, and habitat conditions.
Central Arizona Basins Surface-Water Sampling Sites
Bed-Sediment and Tissue Sampling
Click
here for a larger view of the bed-sediment and tissue site map. (65K
.gif file)
A typical bed-sediment and tissue sampling reach is selected in the vicinity of the water-column sampling site (see Surface-Water Program). Bed sediment is sampled in 5 to 10 wadeable depositional zones that contain fine-grained particulate matter. Areal spacing of subsamples include the full range of depositional areas within the stream reach. Samples from the top 2 or 3 centimeters of sediment are collected. The composited subsamples are sieved and processed for analyses of trace elements, hydrophobic organic chemicals, total organic carbon, and particle size.
Tissue-sampling sites are colocated with the reaches where the bed sediment is sampled. Target taxa are decided upon after retrospective analysis by the study unit biologist. Target taxa are collected at as many sites as possible within a study unit. National consistency is provided by a National Target Taxa (NATT) List.
For hydrophobic organic compounds, the first priority taxon is the Asiatic clam (Corbicula fluminea). If this taxon is not present, then whole fish from a single species is collected. Bottom-feeders, such as suckers, are of a higher priority than predators, such as largemouth bass. If adequate numbers of a species are not collectable, then no sample is submitted, except in cases of local importance.
For trace elements, the Asiatic clam is again the highest priority. Second priority are aquatic insects from the NATT List, such as caddisflies.
Ecological Sampling
Click
here for a larger view of the ecological sampling sites map (65K .gif
file)
Ecological communities are sampled at all possible Basic and Intensive Fixed Sites (see Surface-Water Program) An ecological sampling reach is chosen where the stream, bank, and flood-plain habitat features are representative of the local area. Reach length varies from 150 to over 500 meters. Algal, benthic invertebrate, and fish communities are sampled from each site. Attemptes are made to include stream runs, riffles, and pools in each reach.
Algal and benthic invertebrate samples are collected from different habitat types, called richest targeted habitat (RTH), depositional targeted habitat (DTH), and qualitative multihabitat (QMH). Fish communities are sampled with electroshocking or seining. Fish are then measured, weighed, identified, and vouchered or released. Instream, bankside, and flood plain habitats are recorded using specified descriptors.
The Biological Quality-Assurance Unit at the USGS Survey National Water-Quality Laboratory monitors taxonomic data, and maintains data bases for study unit and cooperator use.
Intensive Ecological Assessment
Samples are collected at a subset of the Basic and Intensive Fixed Sites to provide information on spatial and temporal variability. Reach-to-reach variability is evaluated at these sites by sampling multiple reaches at a site. Year-to-year variability is assessed by sampling a reach over a span of 3 years.
For site information at the NAWQA DataBase Page:
- Select "Site Information" link under RETRIEVE DATA column
- In the Retrieve Data window, use the "Choose Site Information Query Output" pulldown list, and select "Surface Water"
- When setting paramets for search, select Arizona, and Central Arizona Basins, plus any other parameters needed
- Refer
For water-quality values for the each site listed below:
- Follow instructions above
- Scroll to the column labeled "NAWQA Data for Site" (far right column)
- Select icon
For multiple-site selections at the NAWQA DataBase Page::
- Select "Surface Water/Bed" or "Mixed (SW & GW)" link under the RETRIEVE DATA column
- Select from "Surface Water Query Option" pulldown list
- For assistance selecting Query Option, examine the "Examples of Surface Water Query Output options" link before using Query Option pulldown list.
1. West Clear Creek near Camp Verde, site identifier 09505800.
2. Verde River above mouth of West Clear Creek, site identifier 09505570.
3. Verde River below Tangle Creek, site identifier 09508500.
4. Salt River near Roosevelt, site identifier 09498500.
5. Gila River at Kelvin, site identifier 09474000.
6. San Pedro River at Charleston, site identifier 09471000.
7. Buckeye Canal near Hassayampa, site identifier 332136112434201
8. 91st Avenue waste-water treatment plant outfall near Phoenix, site identifier 09512407
9. Santa Cruz River at Cortaro, site identifier 09486500. SEDIMENT ONLY
10. Santa Cruz River at Tubac, site identifier 09481740.
11. Santa Cruz River near Nogales waste-water treatment plant, site identifier 312731110573901. SEDIMENT ONLY
12. 48th Street Drain near Interstate 10, site identifier 332516111562001.
13. Granite Creek at Prescott, site identifier 09502960
1. San Pedro River near Hereford, 312621110062601.
2. San Pedro River near Highway 90, 313256110080701.
3. San Pedro River at Charleston, 09471000.
4. Gila River at Kelvin, 09474000.
5. Santa Cruz River at Tubac, 09481740.
6. Santa cruz River at Cortaro, 09486500.
7. Salt River near Roosevelt, 09498500.
8. Verde River above West Clear Creek near Camp Verde, 09505570.
9. West Clear Creek near Camp Verde, 09505800.
10. Verde River below Tangle Creek above Horseshoe Dam, 09508500.
11. 91st Avenue waste-water treatment plant outfall near Phoenix, 09512407
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