Many control options for sediments and associated contaminants in storm-water runoff from urban areas rely on settling of solids. This study characterizes particle-size distributions in urban storm-water runoff from specific source areas and land-use categories, with the hopes of assisting watershed managers and engineers design better control devices for reducing sediment in urban runoff.
Problem
Sediments in storm-water runoff from urban areas and contaminants associated with these sediments are a substantial source of contamination to receiving waters and associated toxic effects to aquatic organisms.
Treatment options for urban storm water should include specific plans to target sediment as the primary source of contamination to receiving streams. Watershed managers in urban areas need information to help choose the most effective means to reduce sediment-associated contaminants in urban runoff.
Numerous structural best-management practices (BMPs) provide some level of sediment control and are readily available. However, since many of these devices rely on settling of solids, their effectiveness is largely dependent on the range of particle sizes in storm-water runoff. In order to select the most appropriate BMP for sediment control, characterization of particles found in storm-water runoff becomes increasingly important.
Objectives
The primary objective of this study is to address the first step in providing watershed managers with the information needed to make decisions on treatment options: to characterize particle-size distributions in urban storm-water runoff from specific source areas and land-use categories. This information will be used to assist watershed managers and engineers in designing the most appropriate control device for reduction of sediment in urban storm- water runoff. Additionally, data collected from this study will be used to improve understanding on the uncertainty of measuring sediment in stormwater through the collection, preparation, and analytical reporting process. Furthermore, data will be used to improve the Source Loading and Management Model for Windows (WinSLAMM) data tables with particle-size distribution curves for specific source areas and land uses.
Approach
This study will characterize particle-size distribution in stormwater runoff for several urban land use and source area categories. Flow-weighted water quality samples will be collected by use of autosamplers at locations representing urban source areas (e.g. roof tops, streets, and parking lots) and land uses (e.g. shopping center and strip mall). Sites are chosen based on dominance in the urban landscape and the lack of data available to characterize particle-size distribution.
Below are other science projects associated with this project.
WinSLAMM (Source Loading And Management Model): An urban area nonpoint source water-quality model for Wisconsin
Below are multimedia items associated with this project.
Below are publications associated with this project.
The effect of particle size distribution on the design of urban stormwater control measures
Characterizing the distribution of particles in urban stormwater: advancements through improved sampling technology
Regression modeling of particle size distributions in urban stormwater: Advancements through improved sample collection methods
Characterizing the size distribution of particles in urban stormwater by use of fixed-point sample-collection methods
Development of a depth-integrated sample arm to reduce solids stratification bias in stormwater sampling
Ratios of total suspended solids to suspended sediment concentrations by particle size
Improving the accuracy of sediment-associated constituent concentrations in whole storm water samples by wet-sieving
Below are partners associated with this project.
- Overview
Many control options for sediments and associated contaminants in storm-water runoff from urban areas rely on settling of solids. This study characterizes particle-size distributions in urban storm-water runoff from specific source areas and land-use categories, with the hopes of assisting watershed managers and engineers design better control devices for reducing sediment in urban runoff.
Comparison of median particle size distribution from five source areas and one land use. Problem
Sediments in storm-water runoff from urban areas and contaminants associated with these sediments are a substantial source of contamination to receiving waters and associated toxic effects to aquatic organisms.
Treatment options for urban storm water should include specific plans to target sediment as the primary source of contamination to receiving streams. Watershed managers in urban areas need information to help choose the most effective means to reduce sediment-associated contaminants in urban runoff.
Numerous structural best-management practices (BMPs) provide some level of sediment control and are readily available. However, since many of these devices rely on settling of solids, their effectiveness is largely dependent on the range of particle sizes in storm-water runoff. In order to select the most appropriate BMP for sediment control, characterization of particles found in storm-water runoff becomes increasingly important.
Objectives
The primary objective of this study is to address the first step in providing watershed managers with the information needed to make decisions on treatment options: to characterize particle-size distributions in urban storm-water runoff from specific source areas and land-use categories. This information will be used to assist watershed managers and engineers in designing the most appropriate control device for reduction of sediment in urban storm- water runoff. Additionally, data collected from this study will be used to improve understanding on the uncertainty of measuring sediment in stormwater through the collection, preparation, and analytical reporting process. Furthermore, data will be used to improve the Source Loading and Management Model for Windows (WinSLAMM) data tables with particle-size distribution curves for specific source areas and land uses.
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.Public domain Approach
This study will characterize particle-size distribution in stormwater runoff for several urban land use and source area categories. Flow-weighted water quality samples will be collected by use of autosamplers at locations representing urban source areas (e.g. roof tops, streets, and parking lots) and land uses (e.g. shopping center and strip mall). Sites are chosen based on dominance in the urban landscape and the lack of data available to characterize particle-size distribution.
- Science
Below are other science projects associated with this project.
WinSLAMM (Source Loading And Management Model): An urban area nonpoint source water-quality model for Wisconsin
The WinSLAMM model is used to identify sources of pollutants in urban stormwater runoff and to evaluate management alternatives for reducing pollutants. USGS studies provide stormwater flow and pollutant-concentration data for calibrating and verifying WinSLAMM for use in Wisconsin. - Multimedia
Below are multimedia items associated with this project.
- Publications
Below are publications associated with this project.
The effect of particle size distribution on the design of urban stormwater control measures
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 ProgramAuthorsWilliam R. Selbig, Michael N. Fienen, Judy A. Horwatich, Roger T. BannermanCharacterizing the distribution of particles in urban stormwater: advancements through improved sampling technology
A new sample collection system was developed to improve the representation of sediment in stormwater by integrating the entire water column. The depth-integrated sampler arm (DISA) was able to mitigate sediment stratification bias in storm water, thereby improving the characterization of particle size distribution from urban source areas. Collector streets had the lowest median particle diameter oAuthorsWilliam R. SelbigRegression modeling of particle size distributions in urban stormwater: Advancements through improved sample collection methods
A new sample collection system was developed to improve the representation of sediment entrained in urban storm water by integrating water quality samples from the entire water column. The depth-integrated sampler arm (DISA) was able to mitigate sediment stratification bias in storm water, thereby improving the characterization of suspended-sediment concentration and particle size distribution atAuthorsWilliam R. Selbig, Michael N. FienenCharacterizing the size distribution of particles in urban stormwater by use of fixed-point sample-collection methods
The U.S Geological Survey, in cooperation with the Wisconsin Department of Natural Resources (WDNR) and in collaboration with the Root River Municipal Stormwater Permit Group monitored eight urban source areas representing six types of source areas in or near Madison, Wis. in an effort to improve characterization of particle-size distributions in urban stormwater by use of fixed-point sample colleAuthorsWilliam R. Selbig, Roger T. BannermanDevelopment of a depth-integrated sample arm to reduce solids stratification bias in stormwater sampling
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 aAuthorsWilliam R. Selbig, Roger T. BannermanRatios of total suspended solids to suspended sediment concentrations by particle size
Wet-sieving sand-sized particles from a whole storm-water sample before splitting the sample into laboratory-prepared containers can reduce bias and improve the precision of suspended-sediment concentrations (SSC). Wet-sieving, however, may alter concentrations of total suspended solids (TSS) because the analytical method used to determine TSS may not have included the sediment retained on the sieAuthorsW.R. Selbig, R.T. BannermanImproving the accuracy of sediment-associated constituent concentrations in whole storm water samples by wet-sieving
Sand-sized particles (>63 ??m) in whole storm water samples collected from urban runoff have the potential to produce data with substantial bias and/or poor precision both during sample splitting and laboratory analysis. New techniques were evaluated in an effort to overcome some of the limitations associated with sample splitting and analyzing whole storm water samples containing sand-sized partiAuthorsW.R. Selbig, R. Bannerman, G. Bowman - Partners
Below are partners associated with this project.