This study assesses the water quality of the Upper Santa Cruz Watershed in southern Arizona in terms of fecal coliform and Escherichia coli (E. coli) bacteria concentrations discharged as treated effluent and from nonpoint sources into the Santa Cruz River and surrounding tributaries. The objectives were to (1) assess the water quality in the Upper Santa Cruz Watershed in terms of fecal coliform and E. coli by comparing the available data to the water quality criteria established by Arizona, (2) to provide insights into fecal indicator bacteria (FIB) response to the hydrology of the watershed and (3) to identify if point sources or nonpoint sources are the major contributors of FIB in the stream. Assessment of the available wastewater treatment plant treated effluent data and in-stream sampling data indicate that water quality criteria for E. coli and fecal coliform in recreational waters are exceeded at all locations of the Santa Cruz River. For the wastewater discharge, 13%-15% of sample concentrations exceeded the 800 colony forming units (cfu) per 100 mL sample maximum for fecal coliform and 29% of samples exceeded the full body contact standard of 235 cfu/100 mL established for E. coli; while for the in-stream grab samples, 16%-34% of sample concentrations exceeded the 800 cfu/100 mL sample maximum for fecal coliforms and 34%-75% of samples exceeded the full body contact standard of 235 cfu/100 mL established for E. coli. Elevated fecal coliform and E. coli concentrations were positively correlated with periods of increased streamflow from rainfall. FIB concentrations observed in-stream are significantly greater (p-value < 0.0002) than wastewater treatment plants effluent concentrations; therefore, water quality managers should focus on nonpoint OPEN ACCESSWater 2013, 5 244 sources to reduce overall fecal indicator loads. Findings indicate that fecal coliform and E. coli concentrations are highly variable, especially along urban streams and generally increase with streamflow and precipitation events. Occurrences of peaks in FIB concentrations during baseflow conditions indicate that further assessment of ecological factors such as interaction with sediment, regrowth, and source tracking are important to watershed management.

A stratified, spatially balanced sample with unequal probability selection was used to design a multipurpose survey of headwater streams in the Mid‐Atlantic Coastal Plain. Objectives for the survey include unbiased estimates of regional stream conditions, and adequate coverage of unusual but significant environmental settings to support empirical modeling of the factors affecting those conditions. The design and field application of the survey are discussed in light of these multiple objectives. A probability (random) sample of 175 first‐order nontidal streams was selected for synoptic sampling of water chemistry and benthic and riparian ecology during late winter and spring 2000. Twenty‐five streams were selected within each of seven hydrogeologic subre‐gions (strata) that were delineated on the basis of physiography and surficial geology. In each subregion, unequal inclusion probabilities were used to provide an approximately even distribution of streams along a gradient of forested to developed (agricultural or urban) land in the contributing watershed. Alternate streams were also selected. Alternates were included in groups of five in each subregion when field reconnaissance demonstrated that primary streams were inaccessible or otherwise unusable. Despite the rejection and replacement of a considerable number of primary streams during reconnaissance (up to 40 percent in one subregion), the desired land use distribution was maintained within each hydrogeologic subregion without sacrificing the probabilistic design.

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Because of their large numbers and biogeochemical activity, small water bodies (SWB), such as ponds and wetlands, can have substantial cumulative effects on hydrologic, biogeochemical and biological processes, yet the spatial distributions of various SWB types are often unknown, especially in modified landscapes. Using updated National Wetland Inventory data, we compare the spatial distribution of SWB types across various ecoregions and land covers within the state of Indiana. Of 203 942 total SWB, 75% contain a permanent water feature and 80% of those SWB are classified as excavated or impounded ponds. Both underlying geology and human modifications influence SWB distributions. Wetlands are most prevalent in the agricultural Drift Plain and are larger with a greater range of sizes than man‐made open water features. Small impoundment ponds dominate the southern forested region of the Interior Plateau. Analysis of variance of slopes from power law distributions confirms differences between SWB distributions in the Drift Plain and the Interior Plateau as well as differences between forested wetlands and diked and excavated open waters across ecoregions. SWB densities are lowest in the Corn Belt regions and in agriculture overall. SWB in urban lands tend to have higher median area than natural or agricultural lands and have intermediate densities. This analysis highlights the presence of hydrological modifications in SWB distributions, namely the potential legacy of wetland removal and pond creation practices in the state. Determining these modified distributions and patterns is the first step in understanding cumulative SWB influences on various ecological processes in modified landscapes. Copyright © 2015 John Wiley & Sons, Ltd.