This issue includes a Featured Collection on "Contaminants of Emerging Concern," with William Battaglin and Dana Kolpin as the Guest Associate Editors. These papers arose from the AWRA 2007 Summer Specialty Conference in Vail, Colorado. The conference provided an overview of the detection and sources of contaminants of emerging concern, their fate and transport in natural and engineered systems, receptors and effects, and social and engineering solutions to problems.

Chalew and Halden present a synthesis of the toxicological effects that two routinely used synthetic biocides, triclosan and triclocarban, can have on wildlife, laboratory animals, and human cell cultures.
Sellinet al. investigate the occurrence of estrogenic compounds in Nebraska streams.
Kitamura et al. expose Japanese medaka to estrogenic compounds in a variety of controlled conditions.
Wu et al. use Escherichia coli (E. coli) as a bacterial tracer for water and sediment bound transport of microbial pathogens.
Phillips and Chalmers look for organic wastewater compounds in urban runoff, combined sewer overflows, and wastewater treatment plant outfalls in Vermont and New York.
Guo and Krasner evaluate caffeine, carbamazepine, primidone, and an N-nitrosodimethylamine formation potential test as indicators of potential wastewater impacts on drinking water sources.
Brown et al. use a lagrangian sampling strategy to assess inputs and losses of emerging contaminants in St. Vrain Creek as it passes through the City of Longmont, Colorado.
Poynton and Vulpe describe the utility of DNA microarrays for assessing potential effects of emerging contaminants.

Additional Technical Papers

Suplee et al. conducted public opinion surveys in Montana to ascertain if the public identifies a level of benthic river and stream algae undesirable for recreation. On-site interviews and a mail survey based on photos showed as benthic algal chlorophyll a levels increased desirability for recreation decreased.

Helms et al. evaluated the impact of land cover on fish assemblages on 18 watersheds of the Lower Piedmont of western Georgia. Fish assemblages were largely explained by physicochemical and hydrological rather than habitat variables. Specifically, fish species diversity, richness, and biotic integrity were lower in streams that received high frequency of spate flows.

Simon et al. evaluated potential reduction in sediment loadings emanating from streambanks by simulating hydraulic and geotechnical processes responsible for mass failure under existing and mitigated conditions using a Bank-Stability and Toe-Erosion Model. Results stress the critical importance of protecting the bank toe-region from steepening by hydraulic forces that would otherwise entrain previously failed and in situ bank materials, thereby allowing the upper bank to flatten (by failure) to a stable slope.

Dow et al. used an on-line drought mapping tool to study which spatial unit best meets the desire drought managers have for ''local'' information, their comprehension of uncertainties introduced in mapping information at local scales, and their willingness to tradeoff accuracy for information at a desired unit. They found the most useful local map information includes regional context and boundaries which present their local area of interest.

Roy and Shuster suggest subset of impervious surfaces routing stormwater runoff directly to streams via stormwater pipes, called directly connected impervious area (DCIA), may be a better predictor of stream ecosystem alteration. They highlight the importance of parcel-scale field assessments for managing suburban watersheds.

Pak et al. follow up an earlier paper on debris from burned watersheds. They developed sediment yield prediction models for use in relatively small watersheds in the greater Los Angeles area.

Patterson and Doyle found a significant increase in flood exposure immediately outside the 100-year floodplain throughout North Carolina. As a result of this unintended consequence of national flood policy, any flood even slightly higher than the 100-year flood will have a disproportionately large impact since development is outside the legal boundary of national flood policy.