Verification of a depth-integrated sample arm as a means to reduce solids stratification bias in urban stormwater sampling

Selbig, William R.; Cox, Amanda L.; Bannerman, Roger T.

doi:10.1039/c2em10999a

Cited by 13 publications

(8 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Clark and Siu (2008) identified several studies that showed that measurements of TSS generally were 20%-40% lower than corresponding SSCs for identical samples analyzed with different methodologies. This seems to indicate that SSC is a better measure of suspended solids, especially with the use of a DISA (Selbig et al 2012), which compensates for solids stratification. However, because TSS often is used by environmental regulators to define suspended solids, solids commonly are measured using both TSS and SSC.…”

Section: Discussionmentioning

confidence: 93%

“…Once a water-level threshold was exceeded, typically a depth of 1.2 cm from the pipe floor, the volume of water passing the station was measured and accumulated at 1-min increments until a volumetric threshold was reached. At that point, a depth-integrated sample arm (DISA) sampler (Selbig et al 2012) in both the influent and effluent pipes collected a discrete water sample and the volumetric counter was reset. Sample collection in the effluent pipe occurred approximately 1 min after sample collection in the influent pipe.…”

Section: Sample Collection and Measurement Of Dischargementioning

confidence: 99%

“…Sample collection in the effluent pipe occurred approximately 1 min after sample collection in the influent pipe. A DISA was used because it collects a water sample from the entire water column, rather than a single, fixed point, thereby limiting concentration bias caused by the stratification of solids in storm sewers (Selbig et al 2012). The process was repeated until the water level receded below the threshold.…”

Section: Sample Collection and Measurement Of Dischargementioning

confidence: 99%

See 2 more Smart Citations

Evaluation of Stormwater Treatment Vault with Coanda-Effect Screen for Removal of Solids and Phosphorus in Urban Runoff

Buer

Selbig

2020

J. Sustainable Water Built Environ.

Self Cite

View full text Add to dashboard Cite

Catch basins commonly are used by cities as part of a stormwater management plan to remove sediment and associated contaminants from stormwater, keeping them in compliance with regulations. Recently, the city of Madison, Wisconsin modified traditional catch basins by incorporating a fine-mesh (1-mm) Coanda-effect screen into the design with the goal of increasing removal of sediment and organic matter from stormwater. The US Geological Survey (USGS), in cooperation with the City of Madison, installed a water-quality monitoring station at such a catch basin to quantify reductions in total suspended solids (TSS), volatile suspended solids (VSS), suspended sediment concentration (SSC), total phosphorus (TP), and dissolved phosphorus (DP) from urban stormwater before entering Lake Monona. A comparison of the cumulative load from 33 samples collected during the summers of 2016 and 2017 showed 23% and 45% reductions in TSS and SSC, respectively. A smaller reduction was observed for TP, 16%, whereas DP remained unchanged. Reported traditional catch basin sediment removal varies greatly, although typical removal rates are similar. Results from this study will help regulated municipalities determine whether the use of screened catch basins can help meet water-quality goals.

show abstract

Section: Discussionmentioning

confidence: 93%

Section: Sample Collection and Measurement Of Dischargementioning

confidence: 99%

Section: Sample Collection and Measurement Of Dischargementioning

confidence: 99%

See 1 more Smart Citation

Evaluation of Stormwater Treatment Vault with Coanda-Effect Screen for Removal of Solids and Phosphorus in Urban Runoff

Buer

Selbig

2020

J. Sustainable Water Built Environ.

Self Cite

View full text Add to dashboard Cite

show abstract

“…This is an important distinction from NURP sample collection methods, which acquired a water sample from a single point in the water column. Laboratory testing showed that the DISA was able to measure sediment concentrations within 7 percent of the true value [27]. The DISA has been used to improve the characterization of sediment concentrations and PSDs in urban stormwater runoff from several different urban source areas and land uses that have consistently shown large departures from the NURP PSD [6].…”

Section: Measured Distributions Using Improved Sample Collection Techmentioning

confidence: 99%

The Effect of Particle Size Distribution on the Design of Urban Stormwater Control Measures

Selbig

Fienen

Horwatich

et al. 2016

Water

View full text Add to dashboard Cite

An urban pollutant loading model was used to demonstrate how incorrect assumptions on the particle size distribution (PSD) in urban runoff can alter the design characteristics of stormwater control measures (SCMs) used to remove solids in stormwater. Field-measured PSD, although highly variable, is generally coarser than the widely-accepted PSD characterized by the Nationwide Urban Runoff Program (NURP). PSDs can be predicted based on environmental surrogate data. There were no appreciable differences in predicted PSD when grouped by season. Model simulations of a wet detention pond and catch basin showed a much smaller surface area is needed to achieve the same level of solids removal using the median value of field-measured PSD as compared to NURP PSD. Therefore, SCMs that used the NURP PSD in the design process could be unnecessarily oversized. The median of measured PSDs, although more site-specific than NURP PSDs, could still misrepresent the efficiency of an SCM because it may not adequately capture the variability of individual runoff events. Future pollutant loading models may account for this variability through regression with environmental surrogates, but until then, without proper site characterization, the adoption of a single PSD to represent all runoff conditions may result in SCMs that are under-or over-sized, rendering them ineffective or unnecessarily costly.

show abstract

“…However, potential concentration gradients should be considered, especially for constituents commonly associated with larger particulates (Taylor et al 2005;Harmel et al 2003Harmel et al , 2006a. Although it is likely unnecessary at EOF sites, a vertical intake with multiple entry points or a depth-integrated sampling arm could be employed to better capture vertical concentration gradients (Gettel et al 2011;Selbig et al 2012). Where this is not feasible, the relationship between concentrations at the intake and in the total cross-section can be established for the range of expected discharges (Ging 1999).…”

Section: Automated Samplers (Electronic)mentioning

confidence: 99%

Measuring edge-of-field water quality: Where we have been and the path forward

Harmel¹,

King²,

Busch³

et al. 2018

Journal of Soil and Water Conservation

View full text Add to dashboard Cite

Heightened pressure to demonstrate the resource benefits of conservation practices and continued high-profile water quality impairments and concerns are increasing the need to quantify edge-of-field (EOF) water quality. With this in mind, this manuscript summarizes previous developments in EOF water quality sampling and presents current research and glimpses into the future. This manuscript focuses on constituent sampling at the field-scale or at the "edge-of-field;" however, many of the findings are also applicable for small stream or small watershed sampling. With development of programmable automated samplers and initiation of numerous automated sampling projects, it became readily apparent that neither equipment manufacturers nor researchers could provide guidance on design components (e.g., sample initiation, timing/intervals, and type). This was problematic as available monitoring resources are too limited and data needs too great for such projects to be designed solely based on field experience and without a scientific basis or with complete disregard for potential data quality implications. Thus practical, science-based guidance for EOF sampling was developed and fundamental understanding of the inherent uncertainty was established to assist researchers, municipalities, consulting firms, and regulatory agencies improve data quality and monitoring resource efficiency. Looking to the future, further improvements are needed related to lower cost systems, practical improvements, and enhanced in situ sampling, along with enhanced understanding and consideration of data uncertainty in modeling and decision making.

show abstract

Verification of a depth-integrated sample arm as a means to reduce solids stratification bias in urban stormwater sampling

Cited by 13 publications

References 14 publications

Evaluation of Stormwater Treatment Vault with Coanda-Effect Screen for Removal of Solids and Phosphorus in Urban Runoff

Evaluation of Stormwater Treatment Vault with Coanda-Effect Screen for Removal of Solids and Phosphorus in Urban Runoff

The Effect of Particle Size Distribution on the Design of Urban Stormwater Control Measures

Measuring edge-of-field water quality: Where we have been and the path forward

Contact Info

Product

Resources

About