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Urban areas produce large amounts of stormwater runoff due to vast areas of impervious surfaces. Stormwater inlets, or catch basins, are commonly used for collecting and directing stormwater runoff away from streets and sidewalks. The conveyances used to direct flow to surface waters may be part of a municipal separate storm sewer systems (MS4s). Typically, MS4s redirect runoff without providing a means for removing harmful pollutants. These pollutants are then often discharged directly into local lakes, rivers, and streams, potentially harming native aquatic ecosystems. Post-construction stormwater practices are commonly used to treat runoff from urban areas by reducing the total runoff volume, lowering peak flow rates, and/or removing harmful pollutants from runoff. However, some post construction stormwater practices require large footprints, construction, and maintenance. Catch basin inserts (CBIs) are one type of post-construction best management practice that are installed within existing catch basins and require no additional land use while still providing a means for removing pollutants from stormwater runoff before entering the MS4. However, limited data is available to demonstrate the expected performance of various CBIs to ensure that these practices meet the pollutant removal standards set forth by the US Environmental Protection Agency (USEPA). The objective of this study was to evaluate the sediment removal capabilities of eight different proprietary CBI products for potential use as a post-construction stormwater practice for Department of Transportation projects. Results indicate that only two basket-type CBIs met the 80% sediment retention benchmark established for the study. While not surpassing the benchmark, three bag-type CBIs did achieve more than 70% sediment retention. The remaining three CBIs (one basket-type, one bag-type, and one cartridge type) fell notably short of the performance benchmark. [ABSTRACT FROM AUTHOR]

Water quality credit trading has been advanced as a cost‐effective means of achieving regulatory compliance. However, the volume of trading activity in operational programs is typically less than estimated by empirical analysis. The compliance behavior of Virginia Municipal Separate Storm Sewer Systems (MS4s) is studied in response to the Chesapeake Bay total maximum daily load (TMDL) to understand the circumstances in which trading is adopted, the extent to which trading is adopted, and the factors contributing to trading's use or nonuse. Results indicate that MS4s generally prefer to install their own pollutant control measures rather than trade. Many MS4s, however, rely on trade as a backup compliance option. MS4s favor bay compliance options that help meet other local management objectives (erosion control, infrastructure protection, and reductions toward local water quality objectives) and provide long term pollutant control benefits. Low cost term credits do not provide such benefits. For perpetual credits, MS4s use a variety of strategies to substantially reduce the cost differences between trade and nontrade compliance options. [ABSTRACT FROM AUTHOR]

Abstract—The results of a bacterioplankton study (total abundance; saprophytic, hydrocarbon oxidizing, and phenol resistant bacteria; total microbial count; and coliform bacteria) in an urbanized tributary of Lake Onego in 2015 are presented. The lower reaches of the Lososinka River flow over the territory of the city of Petrozavodsk (Karelia) and receive 14 untreated storm runoff streams from the municipal storm sewers. Differences in the temporal abundance dynamics of bacteria, which are indicators of oil pollution, the sanitary condition, and saprobity, were found between the reference and urban parts of the river. These variations are not related to the hydrological and thermal regime of the river and reflect the impact of the pollutant discharge from the urban area on the formation of the bacterial community of the river. The study revealed a significant increase in all the studied indicators of the quantitative development of bacterioplankton in the urban part of the river as compared to the reference part. The number of heterotrophic bacteria of various ecological–trophic groups decreases in the lake water by a factor of 8–16 already at a distance of 500 m from the mouth of the river due to dilution. A significant decrease in the numbers of hydrocarbon oxidizing bacteria in the river water and an increase in sanitary-indicative microorganisms are shown to have occurred over four years. Within the city limits of Petrozavodsk, the Lososinka River has been assessed as polluted with petroleum products, as well as organic substances of fecal origin and unfit for recreation based on the level of the indicator bacteria. [ABSTRACT FROM AUTHOR]

Onsite molecular diagnostics can revolutionize fecal pollution source tracking. We aimed to validate a method for onsite qPCR assays with a miniature speaker-sized Q qPCR instrument and other portable equipment items. We showed that marker genes for total bacteria (16S) and E. coli (rodA) in 100 mL of river water measured with this method agreed within ±0.3 log10 units with results obtained when using conventional laboratory equipment items. We then deployed the portable method in a mobile laboratory ('lab in a van') and quantified HF183 marker genes for human host associated Bacteroides in river water within 3 h of sampling. We also used the mobile laboratory to investigate urban river water and effluents from two storm drains and a retention pond and collected comprehensive microbial and physicochemical water quality data. We found significantly higher HF183 gene levels in the older storm drain compared to the river water (6.03 ± 0.04 vs. 4.23 ± 0.03 log10 gene copies per 100 mL), and a principal component analysis revealed that storm drain effluent retention in a pond beneficially altered water characteristics, making them more like those of the receiving river. In conclusion, onsite qPCR assays can be performed with portable equipment items to quickly test water. [ABSTRACT FROM AUTHOR]

In arid and semi‐arid regions, many rivers experience extremely low flow conditions during seasonal dry periods. During these times, effluent from wastewater treatment plants can make up the majority of flow in the river. However, water quality in urban systems can also be strongly influenced by the natural or human‐influenced flow regime and discharge from other anthropogenic sources such as industrial operations and runoff from impervious surfaces. In this study, we aimed to determine whether water quality was controlled primarily by wastewater discharge in an effluent‐dominated river. Between May 2016–May 2019, we systematically measured water temperature, pH, dissolved oxygen, biochemical oxygen demand, and the concentrations of nitrate‐N, ammonia‐N, and orthophosphate in the South Platte River in the Denver metropolitan area, Colorado, USA. We found that, despite being an effluent‐dominated river, wastewater treatment plant discharge was not the principal factor controlling water quality in many of the sampled areas. Non‐point source pollution from impervious surfaces, delivered to the river through storm drains and minor tributary streams, also contributed to the high nutrient conditions in several locations. We also noted a strong seasonality in water quality, with higher concentrations of nutrients and higher biochemical oxygen demand in the winter months when wastewater effluent can make up more than 90% of the flow in the river. Thus, the interaction of discharge location and reduced seasonal flow produced spatio‐temporal hot spots of diminished water quality. More stringent enforcement of water quality regulations may improve water quality in this system. However, a large portion of the pollution seems to be from non‐point sources, which are very difficult to control. [ABSTRACT FROM AUTHOR]

Abstract Winery wastewater generated during vinification is often co-treated with the municipal wastewater at the biological sections of the municipal wastewater treatment plants prior to its discharge into the environment, and the grey water footprint associated with these discharges are often neglected from water footprint assessments of the wine-making process. This study presents a method for assessing the grey water footprint associated with winery wastewater co-treated with the municipal wastewater at municipal wastewater treatment plants. The applicability of this method is illustrated with a case study for the Niagara Region of Ontario, Canada. The total grey water footprint of treated winery wastewater effluents discharged to surface waters was determined to be 1.47 × 107 m3/yr. Co-treatment substantially decreased the grey water footprint compared to that of the untreated winery wastewater (99.3% reduction). However, the co-treated winery wastewater still exerts a substantial grey water footprint equivalent to over 960 times its total average annual volume and should not, therefore, be excluded from a water footprint assessment of wine-making processes. The grey water footprint is very sensitive to changes in the assumed values of background concentration and maximum allowable parameter concentrations in the surface water receiver, and varies significantly for each parameter of concern. Accounting for variations in background concentration of the receiver, Lake Ontario, Canada, between the discharge locations of the individual wastewater treatment plants increased the calculated grey water footprint by an order of magnitude. An understanding of the variations in receiver water quality should be considered as a part of a grey water footprint analysis that combines the footprints of multiple effluent streams. Highlights • Grey water footprint assessments of treated winery wastewater effluents are missing in the literature. • Total grey water footprint of treated WWW discharged into surface water receivers was estimated for Niagara Region, Canada. • Co-treatment of winery wastewaters in municipal WWTPs reduced their grey water footprint. • Treated winery wastewater effluents that meet regulatory requirements still exert a substantial grey water footprint. • The grey water footprint of treated winery wastewater should not be excluded from water footprint assessments. [ABSTRACT FROM AUTHOR]

Municipal separate storm sewer systems (MS4s) function in urbanized areas to convey flows during both wet weather (i.e., stormwater) and dry weather (i.e., urban runoff as well as subsurface sources of flow) to receiving waters. While urban stormwater is known to contain microbial and chemical pollutants, MS4 dry weather flows, or non-stormwater discharges (NSWDs), are much less studied, although they are also known to contain pollutants, especially when these flows include raw sewage. In addition, some natural NSWDs (e.g., from groundwater infiltrating MS4 pipes) are critical for aquatic habitat protection. Thus, it is important to distinguish NSWD sources to prevent non-natural flows while retaining natural waters (i.e., groundwater). Here, MS4 dry weather flows were assessed by analyzing water samples from MS4 outfalls across multiple watersheds and water provider service areas in south Orange County, CA; potential NSWD sources including sewage, recycled water, potable water, and groundwater were sampled and analyzed for their likely contributions to overall NSWDs. Geochemical and microbiological water quality indicators, as well as bacterial communities, differed across NSWDs, yet water quality within most locations did not vary significantly diurnally or by sampling date. Meanwhile, NSWD source waters had distinctly different bacterial taxa abundances and specific bacterial genera. Shared geochemical and microbial characteristics of certain sources and outfall flows suggested the contributions of sources to outfall flows. The average proportions by sources contributing to MS4 outfalls were further estimated by SourceTracker and FEAST, respectively. The results of this study highlight the use of multiple tools when assessing chemical and microbiological water quality to predict sources of NSWDs contributing to urban MS4 flows during dry weather. This information can be used to support management actions to reduce unnatural and high risk sources of dry weather drainage while preserving natural sources important to environmental health in downstream receiving waters. [Display omitted] • Significantly different water quality across MS4 outfalls and source waters. • Water quality differed across MS4 flows, but not within most locations. • Water quality parameters demonstrated the impacts of source waters on MS4 flows. • Specific bacterial genera associated with source waters. • Proportions predicted by sequencing and some water quality parameters correlated. [ABSTRACT FROM AUTHOR]

A pervious concrete area (50 m2) was constructed for a dual purpose: stormwater management and bicycle parking. It consisted of two subareas (PCa and PCb) with dissimilar characteristics of pervious concrete mixes in strength, durability and permeability. To make the construction more eco-friendly and economical, coal fly ash was incorporated as a partial cement replacement by 21.4% in the PCa pervious concrete mix. The PCb was constructed with an industry proprietary pervious concrete mix. The subbase water storage can retain 4.1 m3 of the infiltrated stormwater before discharging excess water to a storm drain. The drainage water had an improved water quality in turbidity, organic carbon, phosphorus and fecal coliform concentrations. However, it had high pH and conductivity which might cause a negative impact on the environment. The constructed area has been in active use since its opening, accommodating ~30 bicycles at once on the safe and comfort pervious surface. [ABSTRACT FROM AUTHOR]

Groundwater and surface water are often closely coupled and are both under the influence of multiple stressors. Stressed groundwater systems may lead to a poor ecological status of surface waters but to date no conceptual framework to analyse linked multi-stressed groundwater – surface water systems has been developed. In this paper, a framework is proposed showing the effect of groundwater on surface waters in multiple stressed systems. This framework will be illustrated by applying it to four European catchments, the Odense, Denmark, the Regge and Dinkel, Netherlands, and the Thames, UK, and by assessing its utility in analysing the propagation or buffering of multi-stressors through groundwater to surface waters in these catchments. It is shown that groundwater affects surface water flow, nutrients and temperature, and can both propagate stressors towards surface waters and buffer the effect of stressors in space and time. The effect of groundwater on drivers and states depends on catchment characteristics, stressor combinations, scale and management practises. The proposed framework shows how groundwater in lowland catchments acts as a bridge between stressors and their effects within surface waters. It shows water managers how their management areas might be influenced by groundwater, and helps them to include this important, but often overlooked part of the water cycle in their basin management plans. The analysis of the study catchments also revealed a lack of data on the temperature of both groundwater and surface water, while it is an important parameter considering future climate warming. [ABSTRACT FROM AUTHOR]

Massachusetts is one of four states that has the Phase II Small Municipal Separate Storm Sewer System (MS4) General Permits issued by EPA rather than the state Department of Environmental Protection. MS4 permits are issued under the National Pollutant Discharge Elimination System (NPDES) program. Stormwater permitting requirements vary from state to state and by EPA region. The history and status of the Massachusetts MS4 permit will be presented, along with information related to two of the other states under EPA jurisdiction and one state with primacy. In Massachusetts, coordinated efforts were launched by stormwater coalitions, municipalities, and other stakeholder groups to oppose the most recent MS4 permit conditions, with the goal of initiating discussions with EPA to promote more reasonable, practical, and affordable regulation. Currently, several lawsuits are pending with respect to the MS4 permit. Massachusetts is also working toward applying to EPA for primacy of the MS4 program. This effort has support from municipalities and the state but is opposed by environmental groups. [ABSTRACT FROM AUTHOR]

Swales are one type of sustainable drainage system (SuDS) which contribute to the management of water quality in receiving waterbodies. Using a semi-quantitative approach, an impact assessment procedure is applied to the residual water quality that is carried forward to surface waters and groundwaters following treatment within a swale. Both volumetric and pollutant distributions are considered as stormwater passes through the swale system. The pollutant pathways followed by TSS, nitrate, chloride, metals (Cd, Cu, Pb, Zn) and polyaromatic hydrocarbons (PAHs) are determined for a swale receiving highway runoff. For TSS, metals and PAHs between 20% and 29% of the total mean influent pollutant load is predicted to be directed to infiltration through the underlying soils compared to between 4% and 16% of chloride and nitrate. Although surface water impacts are deemed possible, the discharges of swales to groundwaters are assessed to represent a negligible impact for effectively maintained systems. [ABSTRACT FROM AUTHOR]

The purpose of this research was to compare five water quality parameters (BOD, TSS, total zinc, TKN, and fecal coliform) in wet-weather flow of a combined sewer catchment against dry-weather flow, while making a distinction between direct and delayed inflow, which has often not been made. Correlations and event mean concentrations (EMCs) were also calculated. A total of 38 samples were collected from Khon Kaen's combined sewer system between March and August 2015. Concentrations in direct inflow of three parameters: total zinc (... = 0.24 mg/L, IQR = 0.12-0.34), TSS (240 mg/L, 176-356), and BOD (59.7 mg/L, 42.4-77.8) were higher than delayed inflow (... = 0.04 mg/L, 36 mg/L, and 23.7 mg/L, respectively). Concentrations of delayed inflow were similar to or lower than dry-weather flow. Pollutant concentrations for particulate- based pollutants were much higher during the direct inflow phase of rain events compared to the delayed inflow phase. Dissolved-phased nutrients, however, were not different. [ABSTRACT FROM AUTHOR]

Jakkur Lake in the city of Bengaluru covers an approximate area of 55 hectares and primarily receives inflows from the Jakkur sewage treatment plant (STP) and an open storm drain. Jakkur STP discharges an average of 10 million litres of treated water daily (MLD) into the lake. The open drain discharges about 0.5 MLD of raw sewage into the lake. In the absence of environmental flows it becomes critical to assess the impact of nutrient flux on the quality of water, and design cost effective treatment solutions to address the issues of lake water quality. As part of this study, we have assessed the impact of these two primary inflows on the overall water quality of Jakkur Lake. The results have shown that nutrient inflows have led to the increase of chlorophyll-a levels, eventually causing hypereutrophication of Jakkur lake. We have also used simple mass balance approach to assess the contributions of in-lake activities (sedimentation and reaction) on removal of nutrients from the lake. We have concluded that the phosphorus load has to be reduced by approximately 96% from the current levels to prevent algal blooms within Jakkur Lake. [ABSTRACT FROM AUTHOR]

Better understanding of surface water (SW) and groundwater (GW) interactions and water balances has become indispensable for water management decisions. This study sought to characterize SW-GW interactions in three crop fields located in three different irrigated valleys in northern New Mexico by (1) estimating deep percolation (DP) below the root zone in flood-irrigated crop fields; and (2) characterizing shallow aquifer response to inputs from DP associated with irrigation. Detailed measurements of irrigation water application, soil water content fluctuations, crop field runoff, and weather data were used in the water budget calculations for each field. Shallow wells were used to monitor groundwater level response to DP inputs. The amount of DP was positively and significantly related to the total amount of irrigation water applied for the Rio Hondo and Alcalde sites, but not for the El Rito site. The average irrigation event DP using data for the complete irrigation season at each of the three sites was 77.0 mm at El Rito, 54.5 mm at Alcalde and 53.1 mm at Rio Hondo. Groundwater level rise compared to pre-irrigation event water levels ranged from 3 to 1870 mm, and was influenced by differences in irrigation practices between sites. Crop evapotranspiration estimates averaged across irrigation events were highest in Rio Hondo (22.9 mm), followed by El Rito (14.4 mm) and Alcalde (10.4 mm). Results from this study indicate there are strong surface water-groundwater connections in traditionally irrigated systems of northern New Mexico, connections that may be employed to better manage groundwater recharge and river flow. [ABSTRACT FROM AUTHOR]

The presence of microplastics (MPs) in freshwater systems that receive discharge of urban effluent implies a great environmental impact. In order to be able to generate proposals that solve this problem, it is necessary to know in detail the contributions of different MPs sources. The aim of this work was to study the contribution of urban sewage discharge to MPs pollution in a stream that runs through a medium-sized city. The spatial distribution of MPs with sizes between 100 μm and 1.5 mm present in surface water was measured and their characteristics, dimensions, shapes and identification were determined. Physical-chemical parameters of the stream water were measured, and a decrease in water quality was found due to wastewater treatment plants. The main source of MPs was effluent from the plants (97% of the total MPs), while the rest came from storm drains and discharge of tributaries. The maximum concentration of MPs found was around 72,000 MP/L (equivalent to 53 million MPs/s), at a point after discharge from both plants. Around 70% of MPs correspond to microfibers with a mean length of around 300 μm and a mean width of around 15 μm, and they are mainly polyethylene fibers. The remaining 30% of MPs are particles with lengths of around 140 μm. The transport of MPs between a point located after discharge of the plants and another point located about 3 km further on was studied, and no significant variation was found in the concentration of MPs. Electrical conductivity was used as a conservative tracer of MPs concentration. This work presents for the first time a detailed analysis of different contributions of MPs to a freshwater system in South America, which receives discharge of wastewater treatment plants, evidencing its important role in pollution. [Display omitted] • The main source of microplastics was effluent from wastewater treatment plants. • About 70% of microplastics found in the stream correspond to microfibers. • Microfibers have a mean length of around 300 μm. • No significant microplastic retention was found in the stream. [ABSTRACT FROM AUTHOR]

Effective impervious area (EIA), or the portion of total impervious area (TIA) that is hydraulically connected to the storm sewer system, is an important parameter in determining actual urban runoff. EIA has implications in watershed hydrology, water quality, environment, and ecosystem services. The overall goal of this study is to evaluate the application of successive weighted least square (WLS) method to urban catchments with different sizes and various hydrologic conditions to determine EIA fraction. Other objectives are to develop insights on the data selection issues, EIA fraction, EIA/TIA ratio, and runoff source area patterns in urban catchments. The successive WLS method is applied to 50 urban catchments with different sizes from less than 1 ha to more than 2000 ha in Minnesota, Wisconsin, Texas, USA as well as Europe, Canada, and Australia. The average, median, and standard deviation of EIA fractions for the 42 catchments with residential land uses are found to be 0.222, 0.200, and 0.113, respectively. These values for the EIA/TIA ratio in the same 42 catchments are 0.50, 0.48, and 0.21, respectively. While the EIA/TIA results indicate the importance of EIA, 95% prediction interval of the mean EIA/TIA is found to be 0.07 to 0.93, which shows that using an average value for this ratio in each land use to determine EIA from TIA in ungauged urban watersheds can be misleading. The successive WLS method was robust and is recommended for determining EIA in gauged urban catchments. [ABSTRACT FROM AUTHOR]

The article discusses the risk-based asset management in maximizing stormwater program effectiveness. Topics discussed, the funding for the management of stormwater program implementation, the focus of municipal separate storm sewer systems (MS4) on water quality and the consistent processes and procedures for asset definition, inventory and condition assessment.

In urban environments, catch basins serve as major developmental and resting sites for anthropophilic and zoophilic mosquitoes. However, the use of this habitat is inconsistent, with abundance of larvae varying significantly across catch basins at a fine spatial scale. During seasonal summer investigations on mosquito species composition, their spatial and temporal distribution and the environmental characteristic of the breeding sites in the underground storm drain systems of the Wrocław urban area (SW Poland) were assessed from May to September in 2012-2013. The study was conducted in order to develop a rational strategy to control mosquito populations and prevent the potential human exposure to mosquito-transmitted pathogens. Mosquito larvae and pupae were collected and identified weekly from 100 regularly inspected street catch basins located in the town center. All existing and potential breeding habitats in the study area were recorded using a GPS receiver (Magellan MobileMapper CX) and transferred to the computer database. Collected data on the geographical location of inspected breeding places, water quality parameters in inspected catch basins, daily temperature, and precipitation were imposed on orthophotomap in ArcGIS (ESRI, USA). Water quality parameters including pH, electrical conductivity, and water temperature were measured by standard methods. Chemical water analysis of cations (Na, NH, K, Mg, Ca) and anions (Cl, NO, NO, SO) were carried out using Waters Alliance high-performance liquid chromatograph (HPLC) 2695 with 432 Conductivity Detector and 2998 Photodiode Array Detector, an IC-Pak Anion HR column (glauconate/borate eluent) and IC-Pak Cation M/D column (EDTA/HNO eluent). Over two seasonal studies and 3739 samplings in total, 3669 mosquito larvae and 274 pupae/1 dip (from 0 to 110 individuals/dip) were collected by dipper. Culex pipiens s.l. (L.) and Cx. torrentium (Martini) prevailed at all catch basins of the study area as the predominant species. In all examined catch basins, autogenous individuals dominated by far. Breeding activity was first detected in early May. Peak abundance of Culex spp. population in many catch basins was observed in June 2012 and August 2013 when average daily temperatures were increasing and rainfall had declined. Dry periods between rainfalls varied during 2 years of the study period and were noted on June 2012 as well as on July and August 2013. Organically enriched catch basins with significant higher concentrations of Na and NO were found to be more productive breeding habitats. Differences in the Culex immature stage density based on the variables of habitat type, temperature, and precipitation support the need for ongoing surveillance in communities to guide public health officials in planning for and prioritizing mosquito control efforts. [ABSTRACT FROM AUTHOR]

This paper evaluates the effect of six water treatment combinations for the treatment of turbid surface water on four types of emitters by looking at clogging potential and distribution uniformity. The pilot plants use different combinations of upflow gravel filtration, disc filters, and slow sand filtration, fed with natural water from the Cauca River (Cali, Colombia). The outflow of these systems was used to feed four different types of emitters. The paper analyzes the removal of physicochemical parameters that affect emitter clogging and the distribution uniformity of the lower quarter (DUlq). All treatment schemes reduced clogging potential, with the best performance being obtained with upflow gravel filtration followed by slow sand filtration and upflow gravel filters in series. The effect on DUlq differed for the four types of emitters. The longest irrigation time was obtained for the pressure compensated emitter and for the Lyn emitter with 600 h of continuous operation until the DUlq was below 80%. [ABSTRACT FROM AUTHOR]

Question: What are the changes in mineral-rich fens (H7410A) after 25 yr of improved surface water quality in a national park? Location: Stobbenribben floating-fen complex in National Park Weerribben-Wieden, the Netherlands. Methods: Bryophyte species composition, peak above-ground biomass and vascular plant nutrients, as well as electrical conductivity of various layers in the peat weremeasured between 1988 and 2013. Results: The eutrophic moss Calliergonella cuspidata clearly decreased in aerial extent over the 25-yr study, especially near the ditch supplying base-rich surface water to the fen. In contrast, the characteristic rich fen species Scorpidium scorpioides expanded locally near the ditch. In the rich fen zone, peak above-ground biomass decreased from ca. 1000 to 250 g·m-2. Also, foliar N:P ratios in vascular plant tissues increased from 16 to more than 22 g·g-1, which clearly point to lower P availability over time. Improved surface water quality probably also promoted persistence of rich fen habitats in a different way. A large part of the rich fen peatland in 1988 changed into Sphagnum peatland by 2013, probably due to the reduction of base-rich water from below the floating root mat. This mat had become ca. 35 cmthicker in the past 50 yr. However, in areas closer to the ditch, rich fen species persisted, due to inundation with base-rich water during high water periods. Base-rich water probably no longer comes to the surface through the floating rootmat, butmore likely fromthe ditch. Conclusions: Water quality improvement can be important in the long-term re-establishment of target fen species. Also, local inundation can be helpful if regional groundwater access becomes limited. In the national park, rich fens are more threatened than Sphagnum peatlands. This study suggests that the rich fen stage can be maintained, and succession towards Sphagnum peatland prevented, with occasional inundation with high pH, nutrient-poor water. [ABSTRACT FROM AUTHOR]

An important tool in environmental management projects and studies due to the complexity of environmental systems, environmental modeling makes it possible to integrate many variables and processes, thereby providing a dynamic view of systems. In this study the bacteriological quality of the coastal waters of Fortaleza (a state capital in Northeastern Brazil) was modeled considering multiple contamination sources. Using the software SisBaHiA, the dispersion of thermotolerant coliforms and Escherichia coli from three sources of contamination (local rivers, storm drains and submarine outfall) was analyzed. The models took into account variations in bacterial decay due to solar radiation and other environmental factors. Fecal pollution discharged from rivers and storm drains is transported westward by coastal currents, contaminating strips of beach water to the left of each storm drain or river. Exception to this condition only occurs on beaches protected by the breakwater of the harbor, where counterclockwise vortexes reverse this behavior. The results of the models were consistent with field measurements taken during the dry and the rainy season. Our results show that the submarine outfall plume was over 2 km from the nearest beach. The storm drains and the Maceió stream are the main factors responsible for the poor water quality on the waterfront of Fortaleza. The depollution of these sources would generate considerable social, health and economic gains for the region. [ABSTRACT FROM AUTHOR]

In urban areas served by separate sewerage consisting of separate pipe systems it is not uncommon for misconnections to be made either accidentally or deliberately, whereby the wrong effluent is connected to the wrong sewer. The main focus of this problem has been on in-household appliances that are wrongly connected to separate surface water sewers, potentially leading to pollution of receiving waters and non-compliance with statutory water quality standards. This paper examines the available evidence to evaluate the potential scale, severity and cost of the problem in England and Wales in comparison to that reported from investigations in the United States. The particular difficulties associated with distinguishing specific sewage sources in the wastewater “cocktail” discharged at polluted surface water outfalls are reviewed. The deficiencies of existing legislation and enforcing compliance with respect to misconnections are also discussed and the pollution potential resulting from domestic misconnections is explored based on sampled data. [ABSTRACT FROM AUTHOR]

Human faecal contamination poses a widespread hazard for human health. In urban areas, sewer leakage may be an important cause of faecal pollution to surface water. Faecal indicator bacteria (FIB) are the most widely used indicators to monitor surface water quality. However, assessing whether a water body is meeting water quality criteria is made difficult by the high variability of FIB concentrations over time. In this study, the variation of FIB concentration in surface water from tropical urban catchments is investigated. Eleven urban sub-catchments were sampled hourly over 24-hr and samples analysed for FIB. It was found that FIB show a diurnal pattern that is characterised by daytime FIB concentrations that are significantly higher than nighttime FIB concentrations. This observed diurnal variation of FIB closely follows that of sewer flows and contrasts with observations in rural streams where FIB concentrations are known to be low in the daytime and high during the night. Field tracer tests provide qualitative evidence of sewage exfiltration and transport to drains via preferential flow paths. The diurnal FIB variation and field tracer tests indicate the likelihood of surface water contamination due to leaking sewers. The results further suggest that contamination of surface-water drains is likely a widespread problem in tropical urban areas due to extensive drainage networks and the persistence of FIB under tropical conditions. Because of FIB variation over time, the time at which samples are collected is important in being able to capture the daily maximum and minimum FIB concentrations. The Kruskal–Wallis test shows that hourly sampling from 04:00 to 07:00 and from 12:00 to 15:00 results in significantly different FIB concentration (minimum and maximum, respectively). Furthermore, the Wilcoxon-Mann-Whitney test shows that sampling at 12:00 and 14:00 results in significantly higher FIB concentrations, while sampling at 05:00 and 04:00 or 05:00 and 06:00 results in significantly lower FIB concentrations, than sampling at other hours of the day. [ABSTRACT FROM AUTHOR]

Stormwaters, flowing into storm sewers, are known to significantly increase the annual pollutant loads entering urban receiving waters and this results in significant degradation of the receiving water quality. Knowledge of the characteristics of stormwater pollution enables urban planners to incorporate the most appropriate stormwater management strategies to mitigate the effects of stormwater pollution on downstream receiving waters. This requires detailed information on stormwater quality, such as pollutant types, sediment particle size distributions, and how soluble pollutants and heavy metals attach themselves to sediment particles. This study monitored stormwater pollution levels at over 150 locations throughout the Netherlands. The monitoring has been ongoing for nearly 15 years and a total of 7,652 individual events have been monitored to date. This makes the database the largest stormwater quality database in Europe. The study compared the results to those presented in contemporary international stormwater quality research literature. The study found that the pollution levels at many of the Dutch test sites did not meet the requirements of the European Water Framework Directive (WFD) and Dutch Water Quality Standards. Results of the study are presented and recommendations are made on how to improve water quality with the implementation of Sustainable Urban Drainage Systems (SUDS) devices. [ABSTRACT FROM AUTHOR]

Support vector machine (SVM) classification models were constructed using a radial basis functions (RBF). These models were used for classification according to dissolved oxygen, permanganate index, ammoniac nitrogen, total nitrogen, or total phosphorus. Cross-validation and grid-search were applied to find satisfactory parameters for RBF for the improved models. Then the improved models were used to assess water quality utilizing a real-world data set (surface water quality monitoring data). The data set was comprised of more than 2,000 water samples representing 172 different sites monitored for one hydrological year. The results showed that the method presented in this paper had excellent performance, and the SVM classification models performed relatively better than the Linear Discriminant Analysis and Quadratic Discriminant Analysis models for classification. [ABSTRACT FROM AUTHOR]

A consequential life cycle assessment (LCA) is conducted to evaluate the trade-offs between water quality improvements and the incremental climate, resource, and economic costs of implementing green (bioretention basin, green roof, and permeable pavement) versus gray (municipal separate stormwater sewer systems, MS4) alternatives of stormwater infrastructure expansions against a baseline combined sewer system with combined sewer overflows in a typical Northeast US watershed for typical, dry, and wet years. Results show that bioretention basins can achieve water quality improvement goals (e.g., mitigating freshwater eutrophication) for the least climate and economic costs of 61 kg CO2 eq. and $98 per kg P eq. reduction, respectively. MS4 demonstrates the minimum life cycle fossil energy use of 42 kg oil eq. per kg P eq. reduction. When integrated with the expansion in stormwater infrastructure, implementation of advanced wastewater treatment processes can further reduce the impact of stormwater runoff on aquatic environment at a minimal environmental cost (77 kg CO2 eq. per kg P eq. reduction), which provides support and valuable insights for the further development of integrated management of stormwater and wastewater. The consideration of critical model parameters (i.e., precipitation intensity, land imperviousness, and infrastructure life expectancy) highlighted the importance and implications of varying local conditions and infrastructure characteristics on the costs and benefits of stormwater management. Of particular note is that the impact of MS4 on the local aquatic environment is highly dependent on local runoff quality indicating that a combined system of green infrastructure prior to MS4 potentially provides a more cost-effective improvement to local water quality. [ABSTRACT FROM AUTHOR]

Abstract: Organic polymers are widely used as flocculants in pretreatment for microfiltration. However, their impact on microfiltration system performance was not well understood. In this study, the effects of three types of polymer flocculants on microfiltration permeate water quality and membrane fouling were evaluated using a hollow fiber membrane under two different operation modes, coagulation/flocculation-sedimentation-microfiltration (CFSM) and coagulation/flocculation-microfiltration (CFM). Interestingly, the effect of polymers on membrane fouling did not appear to reflect their impact on dissolved organic matter content or floc particle properties in the membrane feed water. The addition of polymer flocculants resulted in floc particles of larger size and smaller fractal dimension and slightly enhanced the removal of dissolved organic matter, both of which were expected to reduce membrane fouling. However, it significantly aggravated membrane fouling in all cases except when the positively charged poly(diallyldimethylammonium) chloride was used in the CFSM process. In particular, all polymers greatly increased hydraulically irreversible fouling in the CFM mode. The increased fouling in the CFSM mode is attributed to the residual polymer, while that in the CFM mode is attributed to the enhanced irreversible floc particle attachment on the membrane surface. Considering the potential severe membrane fouling and the small improvement in treated water quality when polymers are used, the application of polymers in microfiltration pretreatment needs to be carefully evaluated. [Copyright &y& Elsevier]

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Water-quality surveys have confirmed the presence of hormones and antibiotics in surface waters of the United States, which may be of concern to aquatic life. We investigated the concentrations of hormones and antibiotics in surface waters of the state of Delaware to determine - how they compared against environmental thresholds, how they varied across the state, and if they were correlated with land use type. Fifty surface water locations were sampled during early spring and late summer. Water samples were initially screened with ELISA followed by analysis with LC/ MS/ MS. The measured ranges of hormone concentrations were: 0-3.71 ng/l for estrone, 0-4.65 ng/l for estrone-3-sulfate, and 0-6.27 ng/l for 17β-estradiol. The measured ranges of antibiotics were: 0-3.30 ng/l for sulfamerazine, 0-10.74 ng/l for sulfamethoxazole, and 0-2.29 ng/l for tetracycline. The predicted no-effect concentration ( PNEC) for estrone was exceeded for three samples and the PNEC for 17β-estradiol was exceeded for 11 samples. In general, concentrations and detection frequencies were lower in the summer than the spring. The highest concentrations of hormones and antibiotics were spatially distributed in agricultural and urban areas; however, the correlations between land use type and the concentrations were weak. This study was the first statewide survey of hormones and antibiotics for Delaware and provided important baseline data on these emerging contaminants. [ABSTRACT FROM AUTHOR]

Abstract: Stormwater and atmospheric deposits were collected on a small residential urban catchment (0.8 ha) near Paris in order to determine the levels of certain micropollutants (using a preliminary scan of 69 contaminants, followed by a more detailed quantification of PAHs, PCBs, alkylphenols and metals). Atmospheric inputs accounted for only 10%–38% of the stormwater contamination (except for PCBs), thus indicating substantial release within the catchment. On this small upstream catchment however, stormwater contamination is significantly lower than that observed downstream in storm sewers on larger adjacent urban catchments with similar land uses. These results likely stem from cross-contamination activity during transfers inside the sewer system and underscore the advantages of runoff management strategies at the source for controlling stormwater pollutant loads. Moreover, it has been shown that both contamination levels and contaminant speciation evolve with the scale of the catchment, in correlation with a large fraction of dissolved contaminants in upstream runoff, which differs from what has been traditionally assumed for stormwater. Consequently, the choice of treatment device/protocol must be adapted to the management scale as well as to the targeted type of contaminant. [Copyright &y& Elsevier]

Abstract: A quantitative polymerase chain reaction (qPCR) method for the detection of enterococci fecal indicator bacteria has been shown to be generally applicable for the analysis of temperate fresh (Great Lakes) and marine coastal waters and for providing risk-based determinations of water quality at recreational beaches. In this study we further examined the applicability of the method for analyses of diverse inland waters as well as tropical marine waters from Puerto Rico based on the frequencies of samples showing presumptive PCR interference. Interference was assessed by salmon DNA sample processing control (SPC) and internal amplification control (IAC) assay analysis results and pre-established acceptance criteria of <3.0 and <1.5 cycle threshold (Ct) offsets from control samples, respectively. SPC assay results were accepted in analyses of 93% of the inland water samples whereas the criterion was met at frequencies of 60% and 97% in analyses of samples from Puerto Rico in two different years of sampling. The functionality of the control assays and their acceptance criteria was assessed on the basis of relative recovery estimates of spiked enterococci target organisms extracted in the presence of water sample filters and sample-free control filters and was supported by observations that recovery estimates from the water sample and control filters were substantially different for samples that failed these criteria. Through the combined use of the SPC and IAC assays, two presumptive types of interference were identified. One type, observed in the tropical marine water samples, appeared to primarily affect the availability of the DNA templates for detection. The second type, observed in river water samples, appeared to primarily affect PCR amplification efficiency. In the presence of DNA template interference, adjustments from SPC assay results by the ΔΔCt comparative Ct calculation method decreased the variability of spiked enterococci recovery estimates and increased the similarity with control filters as compared to unadjusted recovery estimates obtained by the ΔCt calculation method. Use of a higher salmon DNA concentration in the extraction buffer also reduced this type of interference. The effects of amplification interference were largely reversed by dilution of the DNA extracts and even more effectively by the use of an alternative, commercial PCR reagent, designed for the analysis of environmental samples. [Copyright &y& Elsevier]

The pollution status of the downstream section of the Jakara River was investigated. Dissolved oxygen (DO), 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), suspended solids (SS), pH, conductivity, salinity, temperature, nitrogen in the form of ammonia (NH3), turbidity, dissolved solids (DS), total solids (TS), nitrates (NO3), chloride (Cl) and phosphates (PO3− 4) were evaluated, using both dry and wet season samples, as a measure of variation in surface water quality in the area. The results obtained from the analyses were correlated using Pearson's correlation matrix, principal component analysis (PCA) and paired sample t-tests. Positive correlations were observed for BOD5, NH3, COD, and SS, turbidity, conductivity, salinity, DS, TS for dry and wet seasons, respectively. PCA was used to investigate the origin of each water quality parameter, and yielded 5 varimax factors for each of dry and wet seasons, with 70.7 % and 83.1 % total variance, respectively. A paired sample t-test confirmed that the surface water quality varies significantly between dry and wet season samples (P < 0.01). The source of pollution in the area was concluded to be of anthropogenic origin in the dry season and natural origins in the wet season. [ABSTRACT FROM PUBLISHER]

The extent of impervious cover in a watershed has been linked to the quality of an urban aquatic environment. The Kyeongan watershed in South Korea was investigated to evaluate the relationship between the total impervious area (TIA) and the aquatic ecosystem of the watershed, including water quality and aquatic life using a relatively high-resolution (0.4m) image. The TIA was found to be approximately 12% of the watershed, which indicates that the quality of its environment was being adversely affected by it. For water quality, Pearson correlation analyses showed that all water quality parameters studied were found to be positively correlated with TIA at p < 0.01, except for nitrate (NO3-). In addition, the zone with a higher TIA was found to have worse water quality. Some water quality parameters, such as nitrite (N02-), total phosphorus, and phosphate (P043-) were highly affected by discharges from wastewater treatment plants. Water quality data suggest that TIA could be used to predict the water quality of streams. For ecological parameters, the diatom index for organic pollution and trophic diatom index were found to be highly correlated with TIA, whereas physical habitat and benthic macroinvertebrates were poorly correlated with TIA. However, the results indicate that the extent of impervious cover can be a useful indicator for predicting the status of specific ecosystem of streams. [ABSTRACT FROM AUTHOR]

Abstract: Conduit and other karstic flows to aquifers, connecting agricultural soils and farming activities, are considered to be the main hydrological mechanisms that transfer phosphorus from the land surface to the groundwater body of a karstified aquifer. In this study, soil source and pathway components of the phosphorus (P) transfer continuum were defined at a high spatial resolution; field-by-field soil P status and mapping of all surface karst features was undertaken in a > 30 km2 spring contributing zone. Additionally, P delivery and water discharge was monitored in the emergent spring at a sub-hourly basis for over 12 months. Despite moderate to intensive agriculture, varying soil P status with a high proportion of elevated soil P concentrations and a high karstic connectivity potential, background P concentrations in the emergent groundwater were low and indicative of being insufficient to increase the surface water P status of receiving surface waters. However, episodic P transfers via the conduit system increased the P concentrations in the spring during storm events (but not >0.035 mg total reactive P L−1) and this process is similar to other catchments where the predominant transfer is via episodic, surface flow pathways; but with high buffering potential over karst due to delayed and attenuated runoff. These data suggest that the current definitions of risk and vulnerability for P delivery to receiving surface waters should be re-evaluated as high source risk need not necessarily result in a water quality impact. Also, inclusion of conduit flows from sparse water quality data in these systems may over-emphasise their influence on the overall status of the groundwater body. [Copyright &y& Elsevier]

Karaj and Jajrood rivers are important sources of water supply for Tehran province and special attention should be paid to water quality and its change trends in these rivers. In this study NSFWQI method as well as analytical methods was applied to determine water quality of these rivers. Water quality data sets consist of 9 parameters related to NSFWQI of three years (from April 2006 to March 2009). Parameters in 20 stations of Karaj river and 24 stations of Jajrood river have been examined monthly (except in spring and summer of 2007, as seasonally). On the basis of NSFWQI classifi cation, water quality of two rivers classifi ed as moderate to good quality in this period of time. Results show Karaj river has had better quality, however the WQI of dams' effluent of two rivers are similar. WQI has improved annually over time and the most and the least signifi cant amounts of that occurred during winter and spring, respectively. Correlation analysis showed that DO and temperature have strong negative correlation; however some of other parameters have signifi cant correlation with each other (TS and turbidity). Of the nine parameters, PO4 has had little effect on deterioration of water quality and BOD5 and temperature have had the most and least variations, respectively. [ABSTRACT FROM AUTHOR]

This paper reviews the progress made in the assessment of water resources in South Africa over the past 60 years by examining 5 major studies that were undertaken in this period. These studies illustrate how the exponential growth in computer power and the concomitant development of highly sophisticated tools have changed the manner in which our water resources have been appraised, allowing us to deal with more and more complex issues, including: water quality, surface water/groundwater interaction and the reduction in runoff due to afforestation and alien vegetation. However, the main concern today is the serious decline in hydrological monitoring in recent times. It is imperative that this decline be addressed, especially if we are to deal effectively with problems related to climate cycles and climate change, together with the deterioration in water quality. [ABSTRACT FROM AUTHOR]

Abstract: Despite the regulatory mandate to maintain “natural water quality”, there are ⩾271 storm drain discharges that potentially threaten the 14 designated marine water quality protected areas in Southern California called Areas of Special Biological Significance (ASBS). After sampling 35 site-events, the geomean concentrations of total suspended solids, nutrients, total and dissolved trace metals, and polycyclic aromatic hydrocarbons in the ocean following storm events were similar between reference drainages and ASBS discharge sites. Concentrations of chlorinated hydrocarbons were nondetectable and no post-storm sample exhibited significant toxicity to the endemic purple sea urchin (Strongylocentrotus purpuratus) near ASBS discharge sites. A reference-based threshold was developed and, despite the similarities in average concentrations, there were some individual ASBS discharge sites that were greater than reference background. Cumulatively across all ASBS, the constituents that were most frequently greater than the reference-based threshold were nutrients and general constituents, followed by dissolved and total trace metals. [Copyright &y& Elsevier]

The widespread detection of perfluorinated compounds (PFCs) in the water environment has been a concern for the last several years, while effluents from wastewater treatment facilities are the major sources of these compounds. Even advanced oxidation technologies (AOTs) are not useful for mineralization of the compounds due to their very high stability. Photochemical techniques using particularly vacuum UV (VUV) have been found to be very promising in this regard. But the use of VUV in UV-based AOTs has still not progressed much. Moreover, the impact of water quality on PFCs photomineralization is unknown. This investigation aimed to assess photomineralization potentials of perfluorooctanoic acid (PFOA) in ultrapure water (UPW), tap water (TW), surface water and treated wastewater effluent using a reactor setup enabling maximum utilization of VUV emission of low pressure lamp in laboratory batch experiments. Neya River water (NRW) and the Nakahama Wastewater Treatment Plant Effluent (NWWTPE) represented surface water and treated wastewater effluent respectively. Also, tests were carried out in 50% diluted NRW and NWWTPE. PFOA photomineralization in terms of PFOA removal, defluorination and total organic carbon (TOC) removal are discussed. The usefulness of the method for PFOA mineralization in organic-rich wastewaters, and further research needs are also highlighted. [ABSTRACT FROM AUTHOR]

Over the last three decades, storm-water quality modeling has been used increasingly commonly to describe the general system behavior and assess the pollution loads transferred in and spilled out of combined sewer systems. The calibration of quality models is, in most cases, based on conventionally obtained calibration data, e.g., by automated sampling. Long-term high-resolution online measurement data are available for the Graz West catchment (Graz, Austria), allowing an assessment of the full dynamics of discharge and pollution concentrations. This paper focuses on the application and comparison of single-event and two different multievent optimization schemes for sewer-water quality model calibration. While both single- and multievent optimization lead to satisfying results for the calibration events in discharge calibration, it is shown that validation events are better reproduced by using multievent calibration. Single- and multievent autocalibration of pollution concentration is based on the best dataset obtained from the discharge calibration. As for discharge, the pollutographs are reproduced satisfactorily, and multievent calibration is more stable. In all cases, the two multievent approaches performed equally well. [ABSTRACT FROM AUTHOR]

Under the conditions of tumultuous urbanization and industrialization, the contemporary civilization is characterized by an alarming process of ecologic balance deterioration and water resources pollution. Water resources management is put in difficulty not so much from the point of view of these resources quantity but rather from the point of view of their quality, this being more and more affected by various forms of pollution. Monitoring allows the achievement of four main objectives in knowing water quality, namely supervision, forecasting, warning and intervention. Water quality monitoring allows to make a systematic assessment of water qualitative features, which are in permanent dynamics with significant social and economic implications. The paper presents the objectives of water quality monitoring, aspects related to water monitoring implementation programs, as well as applications of the monitoring system for Jiu river, on the territory of Gorj county. [ABSTRACT FROM AUTHOR]

A new depth-integrated sample arm (DISA) was developed to improve the representation of solids in stormwater, both organic and inorganic, by collecting a water quality sample from multiple points in the water column. Data from this study demonstrate the idea of vertical stratification of solids in storm sewer runoff. Concentrations of suspended sediment in runoff were statistically greater using a fixed rather than multi-point collection system. Median suspended sediment concentrations measured at the fixed location (near the pipe invert) were approximately double those collected using the DISA. In general, concentrations and size distributions of suspended sediment decreased with increasing vertical distance from the storm sewer invert. Coarser particles tended to dominate the distribution of solids near the storm sewer invert as discharge increased. In contrast to concentration and particle size, organic material, to some extent, was distributed homogenously throughout the water column, likely the result of its low specific density, which allows for thorough mixing in less turbulent water. [ABSTRACT FROM AUTHOR]

Abstract: For a better understanding of the short and mid-term impacts of a combined sewer overflow (CSO) on the microbiological quality of the receiving river, we studied the composition of a CSO discharge and monitored during several hours the changes in the concentration of fecal indicator bacteria (FIB) in the impacted river water mass. The CSO occurred at the Clichy outfall (Paris agglomeration, France) in summer 2008 as a result of the most intense rainfall of the year. In 6h, 578, 705 m3 of sewage and 124 t of suspended matter (SM) were discharged into the Seine River. The CSO contained 1.5 × 106 E. coli and 4.0 × 105 intestinal enterococci per 100 mL on average, and 77% of the E. coli were attached to SM. It was estimated that 89% of the CSO discharge was contributed by surface water runoff, and that resuspension of sewer sediment contributed to ∼75% of the SM, 10–70% of the E. coli and 40–80% of the intestinal enterococci. Directly downstream from the CSO outfall, FIB concentrations in the impacted water mass of the Seine River (2.9 × 105 E. coli and 7.6 × 104 intestinal enterococci per 100 mL) exceeded by two orders of magnitude the usual dry weather concentrations. After 13–14 h of transit, these concentrations had decreased by 66% for E. coli and 79% for intestinal enterococci. This decline was well accounted for by our estimations of dilution, decay resulting from mortality or loss of culturability and sedimentation of the attached fraction of FIB. [ABSTRACT FROM AUTHOR]

Riparian ecosystems can harbor great diversity and provide important ecological functions such as improving water quality. The impact of eutrophication on riparian ecosystems, however, is unclear. We conducted a mesocosm experiment to study the effects of nutrient loading on riparian ecosystems. We specifically asked whether the source of nutrients in the riparian zone affects the complex interactions that occur between surface water and adjacent wetlands. We also studied litter decomposition in the wetland component of the mesocosms, because litter accumulation in fens is assumed to control succession toward floating mats. Each mesocosm consisted of an upland component, referred to as the bank, and a water compartment. The bank and water compartments were planted with typical riparian zone and open water fen species prior to the addition of nitrogen (N) and phosphorus (P) in different combinations to either the bank or the surface water. Nutrient addition (mainly P) resulted in increased plant production and higher expansion rates of plants on the bank and in the water. There were also clear interactions in plant responses between the bank and water. Only eutrophic species increased shoot densities after fertilization. Nutrient addition further resulted in higher litter production, especially on the banks, and stimulated decomposition. Both the plant responses and the litter experiment indicated that eutrophication would accelerate succession to floating mats. Such floating fen mats are not likely to have the typical species-rich combination of desirable species; however, as our results suggest that they would be dominated by a few eutrophic species. [ABSTRACT FROM AUTHOR]

The present study fits with an important step into the country development and its hydrous capacity valorization. For that purpose, an evaluation study of surface water quality of Tafna catchment's basin was accomplished. Within the framework of this study, we propose to elaborate a water surface quality maps based on the physic-chemical quality calculation Global Quality Index (GQI). Considering the various indexes and the important amount of data to be handled, we think that it is more judicious to elaborate a computerized program in order to perform an automatic and rapid calculation of different indexes in the time. With the help of the Geographical Information System (GIS) we created a quality maps in accordance with Quality Indexes. The studied has revealed a bad water quality in the whole basin. The registered pollution is of organic type. The main source of water pollution comes from the industrial plants located in the basin. [ABSTRACT FROM AUTHOR]

Yersinia enterocolitica has been detected in surface water, and drinking untreated water is a risk factor for infection. PCR-based methods have been used to detect Y. enterocolitica in various sample types, but quantitative studies have not been conducted in water. In this study, quantitative PCR (qPCR)-based methods targeting the Yersinia virulence genes ail and yadA were used to survey the Grand River watershed in southern Ontario, Canada. Initial testing of reference strains showed that ail and yadA PCR assays were specific for pathogenic biotypes of Y. enterocolitica; however the genes were also detected in one clinical Yersinia intermedia isolate. A survey of surface water from the Grand River watershed showed that both genes were detected at five sampling locations, with the ail and yadA genes detected in 38 and 21% of samples, respectively. Both genes were detected more frequently at colder water temperatures. A screening of Yersinia strains isolated from the watershed showed that the ail gene was detected in three Y. enterocolitica 1A/O:5 isolates. Results of this study show that Yersinia virulence genes were commonly detected in a watershed used as a source of drinking water, and that the occurrence of these genes was seasonal. [ABSTRACT FROM AUTHOR]

The article discusses the study which examines the differences in storm water quality measured during sampling techniques at several locations in stream cross-sections. The researchers have observed different degrees of concentration variability within stream cross-sections for dissolved and particulate constituents. The study indicates some substantial temporal concentration variability for dissolved and particulate constituents, but fails to account for potential variability in cross-sectional concentrations.

It is a well-known fact that baseflow discharge of rainfall runoff significantly impacts the quality of surface water. In this paper, the impact of nitrates discharged as baseflow on stream water quality were studied using PULSE, a hydrograph separation software developed by USGS, to calculate the monthly baseflow discharge. We took water quality and flow rate data from a monitoring station site (code: Ghapcehon2) in Daejeon city and acquired 2005 groundwater quality data in the watershed from government agencies. Agricultural and forestry land use are dominant in the area. The baseflow contributes 85%-95% of stream flows during the spring and fall, 25%-38% during the summer and winter. The monthly nitrate loading discharged as baseflow for Ghapcheon2 was estimated by using monitored nitrate concentrations of groundwater in the watershed. Nitrate loading induced by baseflow at Ghapcheon2 was estimated as 5.4 tons of NO-3 -N/km², which is about 60% of nitrate loading of surface water, or 9.2 tons of NO-3 -N/km². This study shows that groundwater quality monitoring is important for proper management of surface water quality. [ABSTRACT FROM AUTHOR]

Abstract: Provision of surface water has been a long-standing management strategy to enhance habitat for large mammals in southwestern North America. In this paper, we use a resource selection function (RSF) developed from telemetered mountain sheep (Ovis canadensis) in three occupied mountain ranges in the Sonoran Desert, California, USA, to examine the effects of water development on habitat quality within those ranges. Further, we apply that model to four nearby and similar mountain ranges, but for which telemetry data are not available, and again examine the effects of water development. When distance to water was decreased to 2,000 m from an average of 3033 m (±522 [SD]) in three occupied mountain ranges, availability of high-quality habitat increased by as much as 92%. When distance to water was decreased to 2,000 m from an average of 3660 m (±799 [SD]) in three mountain ranges not occupied permanently by mountain sheep, and one occupied range for which telemetry data were not available, the proportion of high-quality habitat resulting from application of our model indicated increases that varied from 116 to 508%. We conclude that development of additional sources of surface water can increase availability of high-quality habitat for mountain sheep inhabiting Sonoran Desert mountain ranges, and that the technique has implications for population persistence and conservation of those large, specialized ungulates. [Copyright &y& Elsevier]