Storm Drainage Research Articles

Rapid Detection of Enteroviruses in Small Volumes of Natural Waters by Real-Time Quantitative Reverse Transcriptase PCR

Despite viral contamination of recreational waters, only bacterial, not viral, indicators are monitored routinely, due to a lack of rapid and cost-effective assays. We used negatively charged filters to capture enteroviruses from seawater and freshwater. Viral RNA was extracted using a commercial kit, and the viruses were quantified by real-time quantitative reverse transcriptase PCR (qRT-PCR). Poliovirus (6.6 to 330,000 virus particles/ml) was added to samples from watersheds in Los Angeles, California, and analysis showed that with 50-ml samples, a cellulose acetate/nitrate (HA) filter yielded final recovery of 51% (r2= 0.99) in fresh water and 23% (r2= 0.90) in seawater. However, for additions of low levels of virus (more likely to represent field samples; <10(4) enterovirus particles/ml), the recovery was lower and more variable, with HA being best in freshwater (17%, r2= 0.97) and the type GF/F glass filter having higher average recovery in seawater (GF/F, 17%; r2= 0.93; HA 12%, r2= 0.87). The optimized method was used with 1-liter field samples from two very different freshwater "creeks" that drain into Santa Monica Bay, California: Topanga Creek (TC), a relatively pristine mountain creek, and Ballona Creek (BC), a concrete-lined urban storm drain. One TC site out of 10 and 2 BC sites out of 7 tested significantly positive for enteroviruses, with higher enterovirus concentrations in BC than in TC (ca. 10 to 25 versus 1 equivalent enterovirus particle/ml). The presented filtration-qRT-PCR approach is fast (<8 h from sampling to results), sensitive, and cost efficient and is promising for monitoring viral contamination in environmental water samples.

Origin of Talc, Iron Phosphates, and Other Minerals in Biosolids

Biosolids (i.e., sewage sludge) contain as much inorganic as organic materials. The inorganic materials include local soils, sediments, and other materials washed down residential, industrial, and storm drains. In this study, the chemistry and mineralogy of the inorganic materials in New York, NY (NYC) biosolids applied to soil surfaces in western Texas from 1992 to 1999 were examined. Inorganic residues were 44 to 77% of whole biosolid weights after oxidation of the organics with H2O2 Inorganic residues consisted largely of silt‐ and clay‐size particles with smaller amounts of fine and very fine sand. Selective dissolution and chemical analyses of the residues indicated &gt;20% Fe phosphates, formed during anaerobic digestion, that contained Al, As, Cr, Cu, Hg, and Zn. X‐ray diffraction, selective dissolution, and surface area analyses showed that the Fe phosphates were poorly crystalline. The mostly quartz and feldspar sands also contained glass shards, textile fibers, and zircon grains. New York City area biosolids contained quartz, feldspars, kaolinite, mica, and expandable layer silicates. Electron microscopy and x‐ray spectra of the clay fractions revealed aggregates of layer silicates and Fe phosphates containing Al, Ca, and Ti. Pigment TiO2, commonly used in foods and cosmetics, contributed Ti to the layer silicate aggregates. Talc derived from cosmetic products was identified in silt and clay fractions by x‐ray diffraction and electron microscopy. Less talc occurred in the 1999 and 1997 biosolids relative to 1992, 1993, and 1994 biosolids suggesting reduced use of talc products. Nationally, cosmetic talc use decreased during that time, probably due to health concerns.

Enumeration and speciation of enterococci found in marine and intertidal sediments and coastal water in southern California

To determine the levels and species distribution of enterococci in intertidal and marine sediments and coastal waters at two beaches frequently in violation of bacterial water standards. Faecal indicator bacteria were extracted from sediment and enumerated using membrane filtration. High levels of enterococci were detected in intertidal sediments in a seasonal river and near a storm drain outlet. Low levels were found in marine sediments at 10 m depths and in surf zone sand. Bacterial isolates presumptively identified as Enterococcus on mEI media were speciated. The predominant species found in both water and sediment included Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, Enterococcus casseliflavus and Enterococcus mundtii. A number of isolates (11-26%) from regulatory water samples presumptively identified as enterococci on mEI media were subsequently identified as species other than Enterococcus. At both study sites, the distribution of species present in water was comparable with those in sediments and the distribution of species was similar in water samples passing and exceeding bacterial indicator standards. High levels of Enterococcus in intertidal sediments indicate retention and possible regrowth in this environment. Resuspension of enterococci that are persistent in sediments may cause beach water quality failures and calls into question the specificity of this indicator for determining recent faecal contamination.

Identifying sources and distributions of sediment contaminants at two US Virgin Islands marinas

Differences in sediment contaminant concentrations within two marinas and adjacent to the marinas in St. Thomas, US Virgin Islands were compared to calculate the portion of those contaminants due to marina activities. In marina 1 (containing no vessel maintenance areas, but with a fuel dock) 88% of observed PAHs and 0% of metals were attributed to marina activities. In the marina/boatyard complex, 46% of PAHs and 89% of metals were attributed to marina sources. The distance from storm drain discharges, and sediment characteristics play a greater role in the distribution and fate of pollutants than do activities associated with a given marina station. The data also provided some evidence that the protection marinas offer to vessels from wind, currents, and waves may concentrate contaminants.

Dry-Weather Metals and Bacteria Loading in an Arid, Urban Watershed: Ballona Creek, California

Dry-season urban runoff from watersheds in arid regions can contribute substantial con- centrations and loads of bacteria and metals to downstream receiving waters. However, there are few studies that have evaluated the relative contributions of different sources of these constituents along a specific creek or channel. This study involved analysis of the relative contribution of vari- ous storm drain sources to the total dry-season loading of metals and bacteria in the Ballona Creek (California) watershed. Approximately 40 actively flowing storm drains and 12 in-river sites were sampled three times during the spring and summer of 2003 for flow, total and dissolved metals, and bacteria. These data were analyzed in terms of mean concentration and load, temporal variability, and spatial distribution of substantial inputs to the creek. In general, Ballona Creek exhibited a bimodal distribution of elevated metals and bacteria, corresponding to locations where storm drains with con- sistently high concentrations and loads discharge to the creek. Of the 40 drains sampled, 4 accounted for 85% of the daily storm drain volume. Between 91% and 93% of the total daily load for metals was contributed by eight drains, while nine drains consistently had the highest concentrations of metals and bacteria. Metals concentrations were observed to vary by up to five-fold and bacterial counts by up to five orders of magnitude on an intra- and inter-annual basis. However, despite this variabil- ity, a relatively small number of storm drain inputs can be expected to account for the majority of loading.

Selection of regional historical rainfall time series as input to urban drainage simulations at ungauged locations

It has become established practice during the past 20 years to use high-resolution historical rainfall time series as input to hydrological model packages for detailed simulation of urban drainage systems. However, sufficiently long rain series are rarely available from the exact catchment in question and simulations are hence often based on available rain series from other locations. Extreme rainfall properties of importance to the performance of urban storm drainage systems vary significantly even in regions with only minor physiographic differences. Part of this variation can be explained by regional variations of the mean annual rainfall and the remaining statistical residue can be interpreted as statistical uncertainty. In Denmark, more than 75 high-resolution rain gauges are installed across a total area of 43,000 m. About 40 gauges had sufficiently long records to be included in a comprehensive national investigation where newly developed statistical regionalisation procedures were used to model the regional variation of extreme rainfalls. On this basis, a spreadsheet model was made available for estimation of extreme design rainfalls and the associated uncertainty at any location in the country. Statistics were furthermore computed to classify historical rainfall time series according to the developed regional model, and this makes it possible to assess the uncertainty related with using different historical rain series for simulations at ungauged locations. This research indicates that use of historical point rainfall data at ungauged locations introduces a significant uncertainty that is largely overlooked in today's practice. The engineering recommendation is to select historical rain series based on an evaluation of the local physiographic characteristics (e.g., the mean annual rainfall) and a (pre-defined) desired safety level of the simulations.

Integrated Approaches in Urban Storm Drainage: Where Do We Stand?

Integrated approaches to urban storm-water drainage management are being increasingly advocated as necessary for advancing more sustainable and holistic management of urban water environments. In this paper, the status of integrated approaches in the management of urban storm-water discharges to receiving waterways is summarized. The starting point of the paper is with the recent scientific contributions, revealing that integration is being pursued and implemented predominantly at two conceptual levels. These include 1) integrating the technical system with the receiving waterway environment, and 2) considering the interaction and influence of the human system with the technical system through processes such as stakeholder and public participation. Additionally, it is argued that the evolving shift towards the implementation of water-quality-based strategies advances the need for further development and application of integrated models and approaches. The cases of online physically based models for predictive control and integrated source control and public participation are presented as examples of such ongoing developments in pursuit of integrated urban storm-water management.

Conception des réseaux d'assainissement

ABSTRACT In 1996, a new standard (NF EN 752-2) about the urban storm drainage network design has been published. It drops the concept of storm return period for the concept of design return period. This choice is fundamentally judicious, however it stays useless because it presently doesn't exist any design method taking into account the concept of design return period. So, the question is: is it possible to change the “old” method based on design storm in order to respect the new standard? The purpose of the study described in this paper is to supply some answers. After a statistical analysis on rainfall series and on flow and volume series generated by the way of a synthetic drainage network, we obtain the following conclusions: concerning the pipe size, the use of design storm guarantees the respect of the NF EN 752-2 standard but often overvalues the size. Concerning the detention tank volume, the use of design storm doesn't guarantee the respect of the NF EN 752-2 standard.

Elegy in Spring Snow

Elegy in Spring Snow Donald Platt (bio) April 8th, a freak snow five days after Easter, and the daffodils, which had opened their mouths and shouted yellow yellow against the sodden mass of brown and purplish dead leaves in our backyard, are now six inches under. The white melting shroud flashes a whiplash of lightning in the sun and makes my eyes wince shut and squint. Everyone leaves shining footprints that by tomorrow will turn to muddy water gargling down the storm drain. I can't stop thinking of the way the curly-haired check-out boy at Evergood Grocery shook each paper bag open with a quick, insouciant flick of the wrist, made the creased paper crack like a slap shot off the rink's boards, and then packed the bag full, canned goods and milk at the bottom, eggs and big heads of frilly escarole on top. Today I heard the cashier tell how last night [End Page 139] the boy's souped-up Camaro had skidded on a slick S curve as he came into work in the falling snow. He hit a concrete pylon head-on. His neck broke. I'm thinking of the blond daffodils packed tight in snow's excelsior, some with their green stems snapped, others that will survive the storm. Who decides what lives or dies? What is this gift we get, snow that blossoms and loads the bare pear trees, then bends their branches to the ground? They don't spring back. Tomorrow we set our clocks forward, lose an hour. It won't matter to the boy who has forgotten daylight and how to save it. Donald Platt Donald Platt’s second book, Cloud Atlas, was published by Purdue University Press as the winner of the Verna Emery Poetry Prize. His work appears in the Georgia Review, Kenyon Review, and the Virginia Quarterly Review, among others. Copyright © 2005 the University of Nebraska Press

Using a rainfall simulator and a physically based hydrological model to investigate runoff processes in a hillslope

A large rainfall simulator (LRS, area 970 m 2 ) is being used to measure flow, sediment and contaminant runoff from a pasture hillslope in the North Island of New Zealand. Results from a winter experiment corresponding to a 1 in 8 year storm were used to calibrate a complex, physically based hydrological model (SHETRAN, Ewen et al., 2002). The ability of SHETRAN to reproduce firstly the observed runoff hydrograph and secondly the soil moisture response, was assessed. Surface runoff was widely distributed over the simulator plot but was not uniform because of uneven topography and possibly because of spatial variations in soil properties. Most model parameters were determined from field measurements, but two (vertical hydraulic conductivity and surface friction) were ‘calibrated’ by matching the observed and predicted runoff hydrograph. The calibrated model had a coefficient of determination (R 2 ) of 98%, and reproduced accurately the shape of the hydrograph and the total volume of runoff. The model predicted soil moisture that matched TDR probe measurements within the calibration uncertainties, at one location, and underestimated the reduction in soil moisture following the end of rain, possibly indicating that the calibrated value of vertical hydraulic conductivity was too low. This study assumed no-flux boundary conditions under and around the LRS, and while this approximation may be acceptable when modelling a single storm, vertical and downslope drainage will need to be quantified in future longer-term applications. From both field data and model simulations, it was concluded that surface runoff occurred principally as a result of the infiltration excess (IE) mechanism. Saturation excess (SE) and variable source area (VSA) were rejected as the principal generation mechanisms. Copyright  2005 John Wiley & Sons, Ltd.

A 24 h investigation of the hydrogeochemistry of baseflow and stormwater in an urban area impacted by mining: Butte, Montana

Changes in water quality during a storm event were continuously monitored over a 24 h period at a single location along an urban stormwater drain in Butte, Montana. The Butte Metro Storm Drain (MSD) collects groundwater baseflow and stormwater draining Butte Hill, a densely populated site that has been severely impacted by 130 years of mining, milling, and smelting of copper-rich, polymetallic mineral deposits. On the afternoon of 26 June 2002, a heavy thunderstorm caused streamflow in the MSD to increase 100-fold, from 0·2 ft3 s−1 to more than 20 ft3 s−1. Hourly discharge and water quality data were collected before, during, and following the storm. The most significant finding was that the calculated loads (grams per hour) of both dissolved and particulate copper passing down the MSD increased more than 100-fold in the first hour following the storm, and remained elevated over baseline conditions for the remainder of the study period. Other metals, such as zinc, cadmium, and manganese, showed a decrease in load from pre-storm to post-storm conditions. In addition to the large flush of copper, loads of soluble phosphorus increased during the storm, whereas dissolved oxygen dropped to low levels (<2 mg l−1). These results show that infrequent storm events in Butte have the potential to generate large volumes of runoff that exceed Montana water quality standards for acute exposure of aquatic life to copper, as well as depressed levels of dissolved oxygen. This study has important implications to ongoing reclamation activities in the upper Clark Fork Superfund site, particularly with respect to management of storm flow, and may be applicable to other watersheds impacted by mining activities. Copyright © 2005 John Wiley & Sons, Ltd.

Towards a roadmap for use of radar rainfall data in urban drainage

Radar rainfall has received growing attention in the urban drainage community since its first appearance on an Urban Storm Drainage Conference in 1984. Still, operational applications of radar rainfall in urban hydrology is limited. The following aspects have to be considered for radar rainfall data use specifically in urban hydrology: the type of the radar, the application requirements on the radar data, the achievable radar data quality, forecast possibilities and limits. Quantitative applications of weather radar to urban hydrology are becoming more mature with better understanding of limitations and achievable accuracy. Research in the US and Europe has led to operational applications of radar to site-specific forecasting of floods and management of sewer overflow during wet weather. The uncertainties and methods for obtaining accurate rainfall measurements at high resolution and with areal extents consistent with urban catchments is a major focus of this article. Evaluation and improvement of quantitative precipitation measurements are described in this overview with specific research and operational examples of radar use in urban hydrology.

Reducing Urban Runoff With Smart ET Controllers: Report Review

This article discusses a new report called the Residential Runoff Reduction Study that gives substantial support to the claim that landscape overwatering and urban runoff can be controlled with a new technology called the evapotranspiration (ET) controller. The four primary purposes of the study were: to expand earlier studies of evapotranspiration (ET) pager‐signal controller technology that have been used to manage irrigation water for residential homes and larger dedicated landscape areas; to evaluate the effectiveness of an education program for customers to enlist their aid in reducing runoff; to determine the connection between proper landscape water application and the quantity and quality of dry weather runoff into storm drain systems; and, to gauge acceptance of the water management technology (ET controllers) and the visual appearance of participant landscapes. The study area included five neighborhoods in Irvine, California. Data was gathered from the 18‐month study and evaluated for water efficiency and savings, dry season runoff changes, and changes in the quality of the dry season runoff water.

Towards a roadmap for use of radar rainfall data in urban drainage

Radar rainfall has received growing attention in the urban drainage community since its first appearance on an Urban Storm Drainage Conference in 1984. Still, operational applications of radar rainfall in urban hydrology is limited. The following aspects have to be considered for radar rainfall data use specifically in urban hydrology: the type of the radar, the application requirements on the radar data, the achievable radar data quality, forecast possibilities and limits. Quantitative applications of weather radar to urban hydrology are becoming more mature with better understanding of limitations and achievable accuracy. Research in the US and Europe has led to operational applications of radar to site-specific forecasting of floods and management of sewer overflow during wet weather. The uncertainties and methods for obtaining accurate rainfall measurements at high resolution and with areal extents consistent with urban catchments is a major focus of this article. Evaluation and improvement of quantitative precipitation measurements are described in this overview with specific research and operational examples of radar use in urban hydrology.

Weed dynamics in the Mediterranean urban ecosystem: ecology, biodiversity and management

SummaryThis paper presents a review of weed dynamics in the Mediterranean urban ecosystem, seen both in an ecological and biological perspective and also in relation to the interaction between human activity and the survival strategies of the various phytocoenoses. Although generalizations on urban weeds cannot easily be drawn on account of the wide range of microenvironments, anemochoric dissemination mechanisms (Asteraceae), resilience (grasses) and perennation are of particular importance. The reasons underlying the undesirability of weeds in the urban environment are investigated. Not only are weeds considered unsightly, but they may also give rise to ‘functional’ obstacles, damaging sidewalks or clogging storm drains. Furthermore, they may adversely affect human health by releasing allergenic pollen into the atmosphere. Management of urban weeds is based almost exclusively on mechanical control, as chemical measures may involve a toxicity risk for man. Paradoxically, certain weeds species may however have a positive effect if they are linked to fauna (butterflies, birds, etc.) considered to give a favourable impression in the cityscape. Finally, the possibility of favouring the biodiversity of the urban ecosystem by introducing some wildflowers typically associated with the degree of biodiversity of the surrounding environment is discussed.

Storm Drains Reduce Runoff, Protect Soil

This article discusses a highly flexible storm drain system project in the new community of Talega, California. Drainage and environmental concerns were paramount in planning the community. The article describes how the storm drain system was designed to capture developed area flows and some of the natural flows in order to reduce flow in the natural creek and thereby control the scour of the natural creek bed.

The hazards of waste

The hazards of waste

The Hazards of Waste

The Hazards of Waste

Inactivation of indicator micro-organisms from various sources of faecal contamination in seawater and freshwater.

The survival of indicator micro-organisms in aquatic systems is affected by both biotic and abiotic factors. Much of the past research on this topic has been conducted using laboratory-generated cultures of indicator bacteria. For this study, we used natural sources of faecal contamination as inoculants into environmental water samples, thereby representing the wide diversity of organisms likely to be found in faecal contamination. Rates of inactivation of water quality indicators, total coliforms (TC), Escherichia coli, enterococci (EC) and F+-specific coliphage were studied in three experiments using inoculants of sewage influent, sewage effluent and urban storm drain run-off. Effects of temperature, nutrients, total suspended solids, bacterial load and solar irradiation were studied in fresh and seawater matrices. Results demonstrated that temperature and solar irradiation had significant effects upon rates of inactivation (anova, P < 0.001). Inactivation rates were similar, regardless of the inoculant type. EC degraded the slowest in the dark with T90s of 115-121 and 144-177 h at 20 and 14 degrees C, respectively. When incubated in sunlight, EC was inactivated significantly more rapidly than either E. coli or F+-specific coliphage (P < 0.001). Inactivation of indicator bacteria is not dependent upon the original source of contamination. Inactivation rates of indicator bacteria were similar in fresh and seawater matrices. However, EC degraded more rapidly in sunlight than E. coli. This study suggests that the source of faecal contamination is not an important factor to inactivation rates of indicator bacteria. However, rates of inactivation of indicator bacteria are likely system specific.

SOURCE VERIFICATION OF INAPPROPRIATE DISCHARGES TO STORM DRAINAGE SYSTEMS

Urban stormwater runoff is traditionally defined as that portion of precipitation which drains from city surfaces exposed to precipitation and flows via natural or man-made drainage systems into receiving waters. But, urban stormwater runoff also includes discharges from many other anthropogenic activities/sources, which find their way into storm drainage systems. The importance of inappropriate discharges into storm drain systems stems from their significant impacts on receiving water quality. Initial studies by Pitt, et al.(1993) and Lalor (1994) reviewed various methodologies to investigate illicit discharges into storm drain systems. The Center for Watershed Protection (CWP) and the University of Alabama are currently conducting a technical assessment of techniques and methods for identifying and correcting illicit and inappropriate discharges geared towards NPDES Phase II Communities, with support provided by Section 104(b)3 funding from the US Environmental Protection Agency (Bryan Rittenhouse is the project officer). Investigation of non-stormwater discharges into storm drainage proceeds along a hierarchy of procedures ranging from exploratory techniques to verification procedures. Exploratory techniques involve an extensive mapping effort to identify the locations of all outfalls for sampling and to outline and characterize the drainage areas contributing to all outfalls. This is followed by the screening analyses at the outfalls which include several visual observations and sampling at repeated intervals at the outfalls in order to measure chemical tracers which would help to identify the general categories of non-stormwater flows. Bacterial concentrations of stormwater flows are more problematic indicators of specific contamination. The use of the flow chart method for identifying most significant flow component would result in identifying the most likely source of contamination based on the concentrations of chemical tracers. Based on recent field studies at the University of Alabama, Tuscaloosa, the flowchart method has been significantly improved to include fewer chemical tracers while giving better results. The flowchart helps differentiate between the major two sub-groups of sources- clean water sources: tap water, spring water and irrigation runoff and the dirty water sources: carwash, laundry, sewage and industrial sources. The use of detergents to differentiate between the clean and dirty water sources can be replaced by boron as a suitable tracer. This is a significant improvement considering the potentially carcinogenic chemicals used in the detergent tests (benzene or chloroform).