Miami River Research Articles

The National Cash Register Company and the Neighborhoods: New Perspectives on Relief in the Dayton Flood of 1913

The National Cash Register Company and the NeighborhoodsNew Perspectives on Relief in the Dayton Flood of 1913 Peter S. Cajka (bio) It is quite obvious that contemporary events shape the writing of history. By viewing their own times, historians ask new questions about the past. The hurricane that hit the Mississippi-Alabama Gulf Coast in August 2005, dubbed Katrina, is turning out be such an event. Scholars have pointed out the devastation wrought by the storm, the slowness in rebuilding New Orleans, and the failings of government. Approximately 1,800 people lost their lives. Systemic relief efforts were few and far between, and the recovery of the city moves at a slow pace. Why did this happen the way it did? Certainly part of the answer lies in the history of the place where it happened, namely the Gulf Coast. Other answers are political, social, and economic. In searching for some answers, it may be useful to reinvestigate the floods that covered the state of Ohio at the end of March 1913—particularly the most devastated location, the city of Dayton. Approximately 360 people perished in the Dayton flood. Yet in just a few months’ time the city was returning to normalcy, and by 1922 the Miami Conservancy District was established to prevent future floods from repeating the episode of 1913. In light of Katrina, the relief and recovery efforts in the Dayton flood of 1913 seem all the more remarkable. Evaluating the events surrounding the Dayton flood provides an instructive case study in the history of relief and recovery from natural disasters. [End Page 49] Coming as it did in March 1913, the flood hit Dayton at a specific moment in the city’s history. Therefore, a brief examination of conditions in Dayton before the flood is necessary. The city, as one historian put it, “is at the mercy of the swollen Miami River.”1 Dayton experienced significant floods in 1814, 1828, 1847, 1866, 1883, 1896, and 1898. After the flood in 1898, Daytonians responded by constructing levies on both sides of the Miami. But their efforts were insufficient in protecting downtown Dayton. Yet, being adjacent to rivers had its advantages. In the early and mid-nineteenth century, waterways were economically valuable to cities in America’s midwestern heartland. The Miami Canal “provided Dayton with cheap transportation, water power, and connections with the outside world.”2 In spite of periodic flooding, and because of the city’s position along the water, Dayton’s population grew from 10,977 in 1850 to 85,333 by 1900.3 Prior to the turn of the century, Dayton underwent an economic shift away from agriculture toward industry. With machinery replacing human labor and a factory boom from steam and gas power, Dayton, in a region of the country that led in industry, science, and invention, stepped early into the industrial age. It witnessed the growth of corporations with its adjunct of salaried managers. Chief among them was the National Cash Register Company (NCR), founded in 1884 by John H. Patterson. Others included the Barney and Smith Company, Davis Sewing Machine Company, Dayton Power and Light Company, Speedwell Motor Car Company, and Dayton Engineer Laboratories Company. The growing wealth of the city could be seen in the urban consumer culture that was well established in Dayton by 1900. The generous selection of goods offered by department stores made the downtown a growing destination for shoppers. The major neighborhoods of the city all had grocery and drugstores, some owned by recent immigrants. The North Side, for example, had nine in-neighborhood grocers.4 Other small business included bicycle shops and printing presses. Around the turn of the century, wealthy residents moved out of downtown Dayton, making more space for banking, business offices, restaurants, and motion picture theaters. Between 1900 and 1910, Dayton grew by 31,000 people, and “the downtown would reap the benefits as more people shopped, banked, ate, and visited the city’s business center.”5 Business districts developed at the intersections of Keowee [End Page 50] and Valley and Third and Williams, the Dayton Arcade was constructed in 1904, Elder and Johnson opened for business in 1905, and the Rike-Kumber...

Potential impact of climate change on flooding in the Upper Great Miami River Watershed, Ohio, USA: a simulation-based approach

This study aims to assess the potential impact of climate change on flood risk for the city of Dayton, which lies at the outlet of the Upper Great Miami River Watershed, Ohio, USA. First the probability mapping method was used to downscale annual precipitation output from 14 global climate models (GCMs). We then built a statistical model based on regression and frequency analysis of random variables to simulate annual mean and peak streamflow from precipitation input. The model performed well in simulating quantile values for annual mean and peak streamflow for the 20th century. The correlation coefficients between simulated and observed quantile values for these variables exceed 0.99. Applying this model with the downscaled precipitation output from 14 GCMs, we project that the future 100-year flood for the study area is most likely to increase by 10–20%, with a mean increase of 13% from all 14 models. 79% of the models project increase in annual peak flow. Citation Wu, S.-Y. (2010) Potential impact of climate change on flooding in the Upper Great Miami River Watershed, Ohio, USA: a simulation-based approach. Hydrol. Sci. J. 55(8), 1251–1263.

Using temperature modeling to investigate the temporal variability of riverbed hydraulic conductivity during storm events

Summary Understanding the impact of storm events on riverbed hydraulic conductivity is crucial in assessing the efficacy of riverbank filtration as a water-treatment option. In this study, the variability of riverbed hydraulic conductivity and its correlation to river stage during storm events was investigated. Water levels and temperatures were continuously monitored in the river using creek piezometers screened beneath the riverbed, and monitoring wells located on the river bank. The range of values for water levels during the study period was from 161.3 to 163.7 m AMSL while temperatures ranged from 3.75 °C to 24 °C. During the duration of the study the Great Miami River was losing water to the underlying aquifer due to pumping in the adjacent municipal well field. Flow and heat transport were simulated in a groundwater heat and flow program VSH2D to determine the hydraulic conductivity of the riverbed. Hydraulic conductivity was estimated by using it as a calibration parameter to match simulated temperatures to observed temperatures in a monitoring well. Hydraulic heads in the aquifer responded to storm events at the same times but with dampened amplitudes compared to the river stage. The relative responses resulted in increased head gradients during the rising limb of the stage-hydrograph. Heat-flow modeling during five storm events demonstrated that a rise in head gradient alone was not sufficient to produce the temperature changes observed in the wells. Simulated temperatures were fitted to the observed data by varying both river stage (as measured in the field) and riverbed hydraulic conductivity. To produce the best fit temperatures, riverbed hydraulic conductivity consistently needed to be increased during the rising and peak stages of the storm events. The increased conductivity probably corresponds to a loss of fine sediments due to scour during high river stage. Hydraulic conductivity increases during storm events varied from a factor of two (0.0951–0.2195 m/d) to almost one order of magnitude (0.0007–0.00658 m/d). Despite these predicted changes the highest model-predicted hydraulic conductivity value was 0.66 m/d, which is still much lower than the infiltration rate used in sand filtration systems (3.59 m/d). These low values suggest that storm events do not pose a significant risk to the water quality at this well field. There was a direct correlation between the duration of rising limb, rate of change of stage and maximum river stage and the magnitude of change of riverbed hydraulic conductivity.

Influences of Spatial Scale and Soil Permeability on Relationships Between Land Cover and Baseflow Stream Nutrient Concentrations

The Little Miami River (LMR) basin, dominated by agriculture, contains two geologically-distinct regions; a glaciated northern till plain with soils three times more permeable than a southern, pre-Wisconsinan drift plain. The influences of two landscape measures, percent row crop cover (%RCC, computed at three spatial scales), and soil permeability (PERM), on baseflow nutrient concentrations were modeled using linear regressions. Quarterly water samples collected for four years were analyzed for nitrate-N (NN), Kjeldahl-N (KN), total-N (TN), and total-P (TP). In till plain streams (n = 17), NN concentrations were 8.5-times greater than drift plain streams (n = 18), but KN and TP were 20-40% lower at comparable %RCC. These differences resulted in TN/TP molar ratios >80 in till plain streams, but <6 in drift plain streams. For till plain steams regression models based on %RCC accounted for 79% of the variance in NN concentrations but only 27% in drift plain streams. However, regressions on %RCC accounted for 68-75% of the KN and TP concentration variance in the drift plain streams but essentially none in the till plain. Catchment PERM influenced the regional NN/KN ratios which were 10-fold higher in the drift plain streams. For both till and drift streams the catchment scale %RCC gave the best predictions of NN, a water soluble anion, but the smaller spatial scales produced better models for insoluble nutrient species (e.g., KN and TP). Published literature on Ohio streams indicates that these inter-regional differences in nutrient ratios have potential implications for aquatic biota in the receiving streams.

Linking Excess Nutrients, Light, and Fine Bedded Sediments to Impacts on Faunal Assemblages in Headwater Agricultural Streams1

Griffith, Michael B., F. Bernard Daniel, Matthew A. Morrison, Michael E. Troyer, James M. Lazorchak, and Joseph P. Schubauer‐Berigan, 2009. Linking Excess Nutrients, Light, and Fine Bedded Sediments to Impacts on Faunal Assemblages in Headwater Agricultural Streams. Journal of the American Water Resources Association (JAWRA) 45(6):1475‐1492.Abstract: Biological impairments in streams are typically defined by regulatory agencies in terms of altered invertebrate or fish assemblages. While nutrients, canopy cover, and sediment fines contribute to these impairments, these stressors are often defined, at least in part, by their impacts on periphyton. Path analysis can extend these assessments to impacts on invertebrates and fish by characterizing the direct and indirect relationships among variables along defined model pathways. With data from headwater tributaries in the Little Miami River, Ohio, we tested models of the impacts of nutrients [total nitrogen (TN), total phosphorus (TP), and the nitrogen to phosphorus (N/P) ratio], the percentage of (%) open canopy, and the % sand and fines on three periphyton metrics [periphytic ash‐free dry mass (AFDM), the percent abundance of cyanobacteria (% cyanobacteria), and the percent abundance of Chlorophyta (% Chlorophyta)] and, in turn, on selected invertebrate or fish metrics. Our objective was to develop and evaluate a statistical model that assesses the direct and indirect impacts of excess nutrients on macroinvertebrate and fish in these streams and demonstrate how this approach might be applicable elsewhere. The results suggest indirect pathways for the influences of nutrients, canopy cover, and fine bedded sediments on invertebrates or fish that are mediated by their influences on periphyton. This is in addition to any direct impacts of these stressors on the invertebrate and fish metrics. In most models, all three periphyton metrics increased with % open canopy. Periphytic AFDM increased with TN, while % cyanobacteria decreased. The % cyanobacteria also decreased with % sand and fines, but % Chlorophyta increased. The metrics, percent abundance of (%) three most dominant (macroinvertebrate) taxa, % Trichoptera, and % herbivorous fish all increased with periphytic AFDM, while % climbers, % swimmers, and %Lepomis cyanellus Rafinesque decreased. Lepomis cyanellus is an indicator species, because it is generally common in these streams and relatively tolerant to various common environmental stressors. The % three most dominant macroinvertebrate taxa increased while % Hydropsychidae (Trichoptera) and %L. cyanellus decreased with % cyanobacteria. The % Trichoptera and %L. cyanellus increased with % Chlorophyta. Some macroinvertebrate metrics, such as the % burrowers and number of burrower taxa, did not have any statistically significant relationships with the periphyton metrics but did exhibit a direct pathway with % sand and fines. These analyses illustrate how path analysis can be used to estimate the relationships among the variables in a conceptual model, modify the model, assess the relative importance of different paths, and explore responses resulting from stressors with interacting and indirect impacts.

Landscape genetic patterns of the rainbow darterEtheostoma caeruleum: a catchment analysis of mitochondrial DNA sequences and nuclear microsatellites

Catchment population structure and divergence patterns of the rainbow darter Etheostoma caeruleum (Percidae: Teleostei), an eastern North American benthic fish, are tested using a landscape genetics approach. Allelic variation at eight nuclear DNA microsatellite loci and two mitochondrial DNA regions [cytochrome (cyt) b gene and control region; 2056 aligned base pairs (bp)] is analysed from 89 individuals and six sites in the Lake Erie catchment (Blanchard, Chagrin, Cuyahoga and Grand Rivers) v. the Ohio River catchment (Big Darby Creek and Little Miami River). Genetic and geographic patterning is assessed using phylogenetic trees, pair-wise F(ST) analogues, AMOVA partitioning, Mantel regression, Bayesian assignment, 3D factorial correspondence and barrier analyses. Results identify 34 cyt b haplotypes, 22 control region haplotypes and 137 microsatellite alleles whose distributions demonstrate marked genetic divergence between populations from the Lake Erie and Ohio River catchments. Etheostoma caeruleum populations in the Lake Erie and Ohio River catchments diverged c. 1.6 mya during the Pleistocene glaciations. Greater genetic separations characterize the Ohio River populations, reflecting their older habitat age and less recent connectivity. Divergence levels within the Lake Erie catchment denote more recent post-glacial origins. Notably, the western Lake Erie Blanchard River population markedly differs from the three central basin tributary samples, which are each genetically distinguishable using microsatellites. Overall relationships among the Lake Erie sites refute a genetic isolation by geographic distance hypothesis. Etheostoma caeruleum populations thus exchange few genes and have low migration among tributaries and catchments.

The Freshwater Mussels (Unionidae) of Twin Creek, Southwest Ohio

ABSTRACT We surveyed the mussel fauna of Twin Creek in southwest Ohio and examined its distribution relative to several selected environmental parameters. Unionid presence was determined with visual searches at 36 sites across 76 km in four counties. Fifteen species from the subfamilies Anodontinae, Ambleminae, and Lampsilinae were recorded, with nine species found alive at 17 of the 36 sites. Mussel species richness and species composition agree in general with historical studies of Twin Creek and other streams in the Great Miami River watershed, although some species have declined or been extirpated. The subfamily Ambleminae was almost completely missing from the area. The presence of three species only as dead and relic shells also may indicate a loss of species richness over the last few decades. Species richness values from Twin Creek were lower than for streams in central and northeastern Ohio.

Characterizing Storm Hydrograph Rise and Fall Dynamics With Stream Stage Data1

Abstract: Storm‐flow transients (i.e., hydrograph rise and fall dynamics) may represent an important aspect of understanding streamflow dynamics. However, little is known about how temporal resolution of transient data and climate variability may color these potential indicators of hydrologic pattern or condition. Warm‐season stream stage and rainfall were monitored continuously (5 min) during the 2002 water year in eight tributaries of the Little Miami River (Ohio), which drain 17‐58 km2 catchments. Rise rates generated using 5‐min data were different than those generated with mean daily data [calculated with the Indicators of Hydrologic Alteration (IHA) software], though fall rates were similar for fine and coarse temporal data. This result suggests that data with low temporal resolution may not be adequate to fully represent the dynamics of storm rise rates. Conversely, fall rates based on daily stage data (via IHA) were similar to those based on the 5‐min data, and so daily mean data may be appropriate for characterizing fall rates. We next analyzed the possible correlations between rainfall variability and storm‐flow stage dynamics. We derived rise and recession rates from storm stage hydrographs by assuming exponential rise and decay of a runoff peak. We found that raw rise rates (Rraw) were correlated with both the maximum rainfall rate and the time to the centroid of a rain event. We subsequently removed the trend based on these rainfall characteristics, which yielded new representations of rise rates abbreviated as Rrate and Rtcent, respectively, and that had lower variability than the uncorrected (raw) data. Fall rates were found to be independent of rainfall characteristics. Due to the predominant influence of stream hydrology upon aquatic biota and nutrient fluxes, our work suggests that these stage data analysis protocols can refine or otherwise reduce variability in these indices by accounting for relevant factors such as rainfall forcing. These protocols for derivation of transient indices should be tested for their potential to improve correlations between stream hydrology and temporally aligned biotic data and dissolved nutrient fluxes in streams.

Integrated Disinfection By-Products (DBP) Mixtures Research: Gene Expression Alterations in Primary Rat Hepatocyte Cultures Exposed to DBP Mixtures Formed by Chlorination and Ozonation/Postchlorination

Large-scale differential gene expression analysis was used to examine the biological effects of disinfected surface waters on cultured rat hepatocytes. Source water from East Fork Lake (Harsha Lake), a reservoir on the Little Miami River in Ohio, was spiked with iodide and bromide and disinfected by chlorination or ozonation/postchlorination. The chlorinated and ozonated/postchlorinated waters were concentrated, respectively, 136- and 124-fold (full strength) by reverse-osmosis membrane techniques. Volatile disinfection by-products (DBP) lost during concentration were restored to the extent possible. Primary rat hepatocytes were exposed to either full-strength or 1:10 or 1:20 dilutions of the concentrates for 24 h and assayed for cytotoxicity and gene expression alterations. The full-strength concentrates were cytotoxic, whereas the diluted samples exhibited no detectable cytotoxicity. Differential gene expression analysis provided evidence for the underlying causes of the severe cytotoxicity observed in rat hepatocytes treated with the full-strength ozonation/postchlorination concentrate (e.g., cell cycle arrest, metabolic stasis, oxidative stress). Many gene expression responses were shared among the hepatocyte cultures treated with dilutions of the ozonation/ postchlorination and chlorination concentrates. The shift in the character of the response between the full-strength concentrates and the diluted samples indicated a threshold for toxicity. A small subset of gene expression changes was identified that was observed in the response of hepatocytes to peroxisome proliferators, phthalate esters, and haloacetic acids, suggesting a peroxisome proliferative response.

An Environmentally Friendly, Cost-Effective Determination of Lead in Environmental Samples Using Anodic Stripping Voltammetry

Contamination of the environment with heavy metals such as lead presents many health risks. Simple, effective, and field-portable methods for the measurement of toxic metals in environmental samples are vital tools for evaluating the risks that these contaminants pose. This article describes the use of new developments in anodic stripping voltammetry (ASV) in an experiment that analyzes environmental samples for Pb content. In this experiment, students extract a sample such as riverbed sediment with dilute acid, facilitated by ultrasonic extraction, and analyze it for Pb using ASV. Owing to complex matrix effects of these samples, the standard addition method is used to determine the concentration of Pb. Determinations of Pb in sediment from the Little Miami River in Ohio showed average Pb levels of 9.3 ± 1.4 ppm. This experiment replaces traditional, costly working electrodes such as glassy carbon with inexpensive, disposable graphite pencil "lead" electrodes. Additionally, bismuth film electrodes are used, which are more environmentally friendly than traditional mercury films and eliminate the cost and hazards of mercury usage and disposal. The primary goal of this experiment is to teach the analytical electrochemical method of ASV for trace metal analysis, and it is targeted for an upper-level undergraduate instrumental methods course, with possible applications in an environmental chemistry course.

Economic valuation of river systems

Contents:DedicationPreface1. The Role of Biology and Ecological Engineering in Watershed and River RestorationTimothy Granata and Ulrike Zika2. Codification, Case Studies and Methods for Economic Analysis of River SystemsFred Hitzhusen3. Estimating Willingness-to-Pay for Additional Protection of Ohio Surface Waters: Contingent Valuation of Water QualityStephen Irvin, Tim Haab and Fred Hitzhusen4. The Economics of High-head Dam Removal in an Ecological Context: A Case Study of the Ballville Dam, Fremont, OhioSarah Kruse, Ulrike Zika and Timothy Granata5. The Economics of Low-head Dam Removal: A Case Study on the Salmon River in Fort Covington, New YorkDavid Warren and Fred Hitzhusen6. Economic Analysis of Infrastructure and Water Quality Improvements in the Muskingum River CorridorFred Hitzhusen, Radha Ayalasomayajula and Sarah Lowder7. Economic Analysis of Water Quality and Recreational Benefits of the Hocking River ValleyAllan Sommer and Brent Sohngen8. Effects of Pesticide Use and Farming Practices on Water Treatment Costs in Maumee River Basin CommunitiesD. Lynn Forster and Chris Murray9. Economic Efficiency and Distribution Evaluation of Dredging of Toxic Sediments and Selected Dam Removal in the Mahoning RiverAshraf Abdul-Mohsen and Fred Hitzhusen10. An Economic Analysis of Lower Great Miami River Segment ImprovementsRadha Ayalasomayajula, P. Wilner Jeanty and Fred Hitzhusen11. The Cuyahoga River Valley Initiative - Framing, Codification and Preliminary Economic Analysis in an Urban River CorridorFred Hitzhusen, Sarah Kruse, Ashraf Abdul-Mohsen, Joana Ferreti-Meza and Marc Hnytka12. Overview, Key Findings and Approaches Including Benefit Transfer for Generalization of Research ResultsFred Hitzhusen and Sarah KruseIndex

A Third Party Tmdl for the East Fork Little Miami River

A Third Party Tmdl for the East Fork Little Miami River

Modeling the Impacts of Farming Practices on Water Quality in the Little Miami River Basin

Since intensive farming practices are essential to produce enough food for the increasing population, farmers have been using more inorganic fertilizers, pesticides, and herbicides. Agricultural lands are currently one of the major sources of non-point source pollution. However, by changing farming practices in terms of tillage and crop rotation, the levels of contamination can be reduced and the quality of soil and water resources can be improved. Thus, there is a need to investigate the amalgamated hydrologic effects when various tillage and crop rotation practices are operated in tandem. In this study, the Soil Water Assessment Tool (SWAT) was utilized to evaluate the individual and combined impacts of various farming practices on flow, sediment, ammonia, and total phosphorus loads in the Little Miami River basin. The model was calibrated and validated using the 1990-1994 and 1980-1984 data sets, respectively. The simulated results revealed that the SWAT model provided a good simulation performance. For those tested farming scenarios, no-tillage (NT) offered more environmental benefits than moldboard plowing (MP). Flow, sediment, ammonia, and total phosphorus under NT were lower than those under MP. In terms of crop rotation, continuous soybean and corn-soybean rotation were able to reduce sediment, ammonia, and total phosphorus loads. When the combined effects of tillage and crop rotation were examined, it was found that NT with continuous soybean or corn-soybean rotation could greatly restrain the loss of sediments and nutrients to receiving waters. Since corn-soybean rotation provides higher economic revenue, a combination of NT and corn-soybean rotation can be a viable system for successful farming.

Climate Change Impacts on Nutrient and Sediment Loads in a Midwestern Agricultural Watershed

The objective of this study is to examine the water quality impacts of climate change in a predominantly agricultural, but rapidly urbanizing, watershed in the American Midwest, the Little Miami River (LMR) watershed. Future climatic conditions were simulated based on various climatic scenarios. The Soil and Water Assessment Tool (SWAT), a long-term, continuous, watershed-scale hydrologic model, was used to predict the potential changes in flow, total nitrogen, total phosphorus, and sediment loads. Results indicate that daily flow can vary by 35%. Besides, the LMR watershed has an overabundance of phosphorus. It is likely that eutrophication will be exacerbated in future climatic conditions; hence strategies to control non-point source pollution by only reducing nitrogen may not be adequate. Moreover, the hydrological impacts of future climate change will be large enough to warrant modifications in our response and utilization of water resources.

Exploring the Variability in Suspended Sediment Yield using BASINS-HSPF and Probabilistic Modeling: Implications for Land Use Planning

The purpose of this study is to examine the use of Monte Carlo simulation method together with BASINS-HSPF, a deterministic water quality simulation model to investigate the variability of sediment yield from various land cover types in the East Fork Little Miami River watershed, Ohio, UISA. The study has two main objectives: first, to obtain interval estimates of suspended sediment yield from urban, agricultural and forest land; and second, to generate probability density and cumulative distribution functions for those estimates. As a result, we will know not only the range of possible values of sediment yield in the watershed but also the probability with which those values are likely to occur. BASINS (Better Assessment Science Integrating Point and Non-Point Sources), a modeling system which provides a Window-based interface for the Hydrologic Simulation Program – Fortran (HSPF), is used in the analysis to simulate streamflow and suspended sediment yield. The daily values of suspended sediment yield from various land cover types generated by BASINS-HSPF are used as input to the Monte Carlo simulation technique that generates probability density and cumulative distribution functions. The distributions are used to draw conclusions about the uncertainty in the hydrologic model predictions in the form of confidence intervals for the predicted sediment yield. The study found that the width of the confidence interval has a critical importance for the evaluation of the model results.

Stumbling Forward: The Organizational Challenges of Building and Sustaining Collaborative Watershed Management

This article examines the challenges of collaborative approaches to ecosystem management associated with the formation and maintenance of new institutions. Individuals who lead collaborative watershed partnerships must grapple not only with complex environmental issues, but also the more mundane—but no less critical—challenges associated with building and sustaining a new organization. The authors focus on the nexus of organizational development and ecosystem (i.e., watershed) management by examining in depth how one group, the Little Miami River Partnership (LMRP), experienced and responded to the challenges of creating a collaborative organization. Results shed light on the disproportionate role that organizational development, as compared to watershed planning, efforts can play in the day-to-day operations of a watershed group. By linking the results to prior research studies, the authors draw conclusions about when and why this disproportionate emphasis on organizational development occurs and implications for practitioners and policymakers.

‘Scavenger’ Boat Helps Restore Miami River's Health

This article presents the Scavenger?, a small sturdy‐looking work boat that has played a major part in restoring the Miami River in Florida to good health. Its goal is to reverse the growth of pollution in this heavily used waterway and to enhance the quality of life along its shores by picking up debris and contaminants from the river's surface and restoring water quality below the surface. The boat's technological water cleaning process is discussed and basically works by introducing enough oxygen into the water to raise dissolved oxygen levels to the maximum that water can contain. Its patented Oxy‐Plus? system is an advanced water decontamination system that treats and revitalizes waterways by directly aerating the water with a combination of ozone and oxygenation. The article includes an insert, The Power of Ozone, that lists the effects of the Oxy‐Plus? system on treated water.

Miami Beach: ASHA’s 2006 Convention

Miami Beach: ASHA’s 2006 Convention

Modelling the hydrologic effects of land-use and climate changes

Climate and land use affect water quantity and quality; however, the complex relations of climate and land use regarding flow and instream nutrient levels have yet to be elucidated. This study aims to assess the hydrologic effects of different land-use and climatic regimes in the Lower Great Miami River Basin. The modelling results from BASINS showed that, as expected, agricultural lands and the wettest scenario yielded the highest amount of streamflow, fecal coliform, and nutrient loadings. But, it was the dry scenario (+2°C, -20% precipitation of the current average climatic conditions in SW Ohio), instead of the driest scenario (+4°C, -20% precipitation), that produced the highest daily nutrient concentrations. When the future land-use and climate scenarios were coupled, the worst situation was found under the current land use and the wettest condition. Hence, a change in land-use pattern may help to alleviate the adverse hydrologic impacts of climate change.

Utility of stable isotopes ( 13C and 15N) to demonstrate comparability between natural and experimental streams for environmental risk assessment

Environmental safety of contaminants sometimes requires testing at the ecosystem level. Model ecosystems can serve as a surrogate to receiving waters for the assessor. Tools to verify that model ecosystems are good surrogates for natural receiving water systems have been based on structural attributes such as taxa lists. While examining taxa lists can be useful within a geography, they are less informative when comparing across different topographical and climatic regions. This paper illustrates an alternative approach that uses natural abundance ratios of nitrogen and carbon. Comparisons were made between the Procter & Gamble Co. (P&G) Experimental Stream Facility (ESF) and the East Fork Little Miami River (EFLMR). We also conducted stable isotopes releases of nitrogen ( 15NH 4Cl) in the ESF and EFLMR. Results from the nitrogen releases for the ESF and EFLMR were compared to each other and to stable isotope releases conducted in 9 streams as part of the Lotic Intersite Nitrogen eXperiment (LINX). Preliminary evaluations of nitrogen uptake show that the uptake rate of ammonium for the P&G experimental streams (0.019 m −1) is similar to uptake rates in natural streams of similar flow and fits the regression of uptake length and discharge for the LINX streams. Nutrient flow data obtained in this study in most cases verified model (SISTM) predictions.