DOCSLIB.ORG

Ofurban Runoff

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Ofurban Runoff Fundamentals of Urban Runoff Management TechNICAL AND INstItutIONAL Issues 2nd Edition | 2007 Earl Shaver Richard Horner Joseph Skupien Chris May Graeme Ridley C H A pter 2 Water Quantity Impacts of Urban Land Use Reality vs. Theory .....................................................................................................................................17 The Rainfall-Runoff Process ................................................................................................................... 20 Runoff Estimation: Typical Parameters .................................................................................................21 Rainfall .............................................................................................................................................21 Time ................................................................................................................................................ 28 Drainage Area ................................................................................................................................30 Soils ................................................................................................................................................ 31 Land Cover ..................................................................................................................................... 34 Runoff Estimation: Methods and Models .............................................................................................36 Runoff Volume Methods ...............................................................................................................36 Peak Runoff Rate Methods ...........................................................................................................36 Runoff Hydrograph Methods .......................................................................................................36 Impacts of Land Use Change .................................................................................................................38 Summary and Conclusions .................................................................................................................... 41 References ............................................................................................................................................... 41 chapter 2: Water Quantity Impacts of Urban Land Use 2-15 C H A pter 2 Water Quantity Impacts of Urban Land Use Urban runoff is a by-product of the land’s surface slope, and the texture, density, and permeability interaction with rainfall. Since, by definition, of the surface and subsurface soils. Conditions that affect urban runoff remains on and moves along the stormwater runoff also include the thickness and quality land’s surface, it is the most visible of the many of the surface cover and the amount of water already forms into which rainfall is converted. This stored both on the surface and within the soil profile. chapter provides the technical fundamentals of Conversely, stormwater runoff also affects the sur- the rainfall-runoff … process. It also describes faces upon which it is created and/or that it flows across. ways that land development alters this process These effects include both the deposition of pollutants and quantifies some of the adverse impacts. captured from the atmosphere by the falling rain and the mobilization and removal of pollutants previously So began Chapter 2 of the 1994 edition of Fun- stored on the surfaces. The most readily visible effects damentals of Urban Runoff Management. And while it are erosion and sedimentation, where forces created by still can serve as the opening paragraph of this new the moving runoff become large enough to dislodge, Chapter 2, our technical knowledge of both urban suspend, and transport soil particles and associated runoff hydrology and the effects of land use change has pollutants downstream. This process continues until grown considerably in the intervening years. As a result, slower velocity areas are encountered, whereupon the the technical content of this new chapter goes beyond particles drop out of the runoff and back onto the the original version, including new and updated topics. surface. Depending on the type and character of the However, in presenting this technical information, the surface cover, this process of dislodging soil particles and chapter’s goal remains the same: to present the infor- mobilizing pollutants can be aided by the impact of the mation not as an end in itself, but so as to assist in the falling raindrops themselves. Further erosion, sedimenta- development of urban runoff management programs. tion, and pollutant loading can occur downstream in The arrival of the EPA’s Stormwater Phase II Final swales, channels, streams, and rivers, depending on the Rule in 1999, which requires municipalities and other rate, depth, velocity, and duration of the runoff flowing entities to develop such programs by 2003, highlights in them. the value of such assistance. The volume of stormwater runoff produced by a From the above, three key conclusions can already rain event, the rates, velocities, and depths at which be reached: it flows, and the pollutants that it carries depend on • Since the volume, rate, and velocity of runoff several factors. In addition to the quantity, intensity, from a particular rain event will depend upon the and duration of the rain itself, the resultant runoff will characteristics of the surfaces on which the rain be determined by the characteristics, condition, and falls, changes to these surfaces can significantly relative areas of the various surfaces on which it falls. change the resultant runoff volume, rate, and As explained in detail in the following sections, these velocity. Changes normally associated with land characteristics include the type of surface cover, the development and urbanization that increase 2-16 fundamentals of urban runoff management impervious cover and decrease soil permeability used to expand readers’ knowledge beyond the pages can significantly increase runoff. of this book. • Since pollutant mobilization and soil erosion It is important to note that, as our understanding of are the direct result of excessive runoff rates urban runoff processes and impacts continues to grow, and durations, changes in land surfaces can also so does the scope and requirements of the programs significantly increase both surface and channel we’ve developed to manage them. Following along and, erosion rates and runoff pollutant loadings. at times, inspiring this growth has been an increasing emphasis on and understanding of runoff fundamentals. • In developing urban runoff management It is this greater understanding that has allowed us to programs, the greater the knowledge of the progress from relatively simple runoff quantity controls rainfall-runoff process, the more effective the in the 1970s to the integrated quantity and quality resultant program will be. programs of today. It has also allowed us to expand While the details of the rainfall-runoff process are the scope and applicability of both our mathematical highly complex and much remains to be learned about models and the various measures and practices we can them, the fundamentals are readily understandable, now use to implement their findings. For example, the particularly when presented in a direct, concise man- growing use of nonstructural measures and low-impact ner. That is the goal of this chapter. Equipped with the development practices essentially began with a detailed information presented here, those involved in develop- re-examination of the fundamental principles of the ing urban runoff management programs at all levels, as hydrologic cycle which, in turn, became the basis for well as those responsible for complying with them, can their design and implementation. Therefore, it is hoped base their efforts on a sound understanding of the basic that the runoff fundamentals presented in this chapter hydrologic processes at the core of their program. will continue to inspire and direct the development of This chapter provides readers with basic information urban runoff programs with ever greater scopes, goals, on the rainfall-runoff process. It also highlights some and accomplishments. of the important unknowns and uncertainties of the process and recommends ways to acknowledge and account for them in computation methods and program Reality vs. Theory requirements. Using this information, the chapter also provides information on the adverse impacts land use In most complex technical matters, differences exist change and urbanization can have on runoff quantity between reality and theory. That is because theories and the damaging consequences of excessive increases developed to explain or simulate reality can only go in runoff rates, volumes, and velocities. so far. Typically, there are aspects of reality that are not Next, the chapter utilizes this rainfall-runoff infor- entirely understood and, therefore, are either ignored or mation to illustrate how various practices can either simplified in the theory. Recognizing these differences avoid or control such impacts. This broad approach is important when developing and implementing a not only helps ensure that decisions made during the technology-based regulatory program such as one that development of an urban runoff management program manages urban runoff. The “real” runoff processes that are based on an informed understanding of runoff occur
Load more

Recommended publications
  • (P 117-140) Flood Pulse.Qxp
    117 THE FLOOD PULSE CONCEPT: NEW ASPECTS, APPROACHES AND APPLICATIONS - AN UPDATE Junk W.J. Wantzen K.M. Max-Planck-Institute for Limnology, Working Group Tropical Ecology, P.O. Box 165, 24302 Plön, Germany E-mail: [email protected] ABSTRACT The flood pulse concept (FPC), published in 1989, was based on the scientific experience of the authors and published data worldwide. Since then, knowledge on floodplains has increased considerably, creating a large database for testing the predictions of the concept. The FPC has proved to be an integrative approach for studying highly diverse and complex ecological processes in river-floodplain systems; however, the concept has been modified, extended and restricted by several authors. Major advances have been achieved through detailed studies on the effects of hydrology and hydrochemistry, climate, paleoclimate, biogeography, biodi- versity and landscape ecology and also through wetland restoration and sustainable management of flood- plains in different latitudes and continents. Discussions on floodplain ecology and management are greatly influenced by data obtained on flow pulses and connectivity, the Riverine Productivity Model and the Multiple Use Concept. This paper summarizes the predictions of the FPC, evaluates their value in the light of recent data and new concepts and discusses further developments in floodplain theory. 118 The flood pulse concept: New aspects, INTRODUCTION plain, where production and degradation of organic matter also takes place. Rivers and floodplain wetlands are among the most threatened ecosystems. For example, 77 percent These characteristics are reflected for lakes in of the water discharge of the 139 largest river systems the “Seentypenlehre” (Lake typology), elaborated by in North America and Europe is affected by fragmen- Thienemann and Naumann between 1915 and 1935 tation of the river channels by dams and river regula- (e.g.
    [Show full text]
  • Managing Storm Water Runoff to Prevent Contamination of Drinking Water
    United States Office of Water EPA 816-F-01-020 Environmental Protection (4606) July 2001 Agency Source Water Protection Practices Bulletin Managing Storm Water Runoff to Prevent Contamination of Drinking Water Storm water runoff is rain or snow melt that flows off the land, from streets, roof tops, and lawns. The runoff carries sediment and contaminants with it to a surface water body or infiltrates through the soil to ground water. This fact sheet focuses on the management of runoff in urban environments; other fact sheets address management measures for other specific sources, such as pesticides, animal feeding operations, and vehicle washing. SOURCES OF STORM WATER RUNOFF Urban and suburban areas are predominated by impervious cover including pavements on roads, sidewalks, and parking lots; rooftops of buildings and other structures; and impaired pervious surfaces (compacted soils) such as dirt parking lots, walking paths, baseball fields and suburban lawns. During storms, rainwater flows across these impervious surfaces, mobilizing contaminants, and transporting them to water bodies. All of the activities that take place in urban and suburban areas contribute to the pollutant load of storm water runoff. Oil, gasoline, and automotive fluids drip from vehicles onto roads and parking lots. Storm water runoff from shopping malls and retail centers also contains hydrocarbons from automobiles. Landscaping by homeowners, around businesses, and on public grounds contributes sediments, pesticides, fertilizers, and nutrients to runoff. Construction of roads and buildings is another large contributor of sediment loads to waterways. In addition, any uncovered materials such as improperly stored hazardous substances (e.g., household Parking lot runoff cleaners, pool chemicals, or lawn care products), pet and wildlife wastes, and litter can be carried in runoff to streams or ground water.
    [Show full text]
  • Analysis of Streamflow Variability and Trends in the Meta River, Colombia
    water Article Analysis of Streamflow Variability and Trends in the Meta River, Colombia Marco Arrieta-Castro 1, Adriana Donado-Rodríguez 1, Guillermo J. Acuña 2,3,* , Fausto A. Canales 1,* , Ramesh S. V. Teegavarapu 4 and Bartosz Ka´zmierczak 5 1 Department of Civil and Environmental, Universidad de la Costa, Calle 58 #55-66, Barranquilla 080002, Atlántico, Colombia; [email protected] (M.A.-C.); [email protected] (A.D.-R.) 2 Department of Civil and Environmental Engineering, Instituto de Estudios Hidráulicos y Ambientales, Universidad del Norte, Km.5 Vía Puerto Colombia, Barranquilla 081007, Colombia 3 Programa de Ingeniería Ambiental, Universidad Sergio Arboleda, Escuela de Ciencias Exactas e Ingeniería (ECEI), Calle 74 #14-14, Bogotá D.C. 110221, Colombia 4 Department of Civil, Environmental and Geomatics Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA; [email protected] 5 Department of Water Supply and Sewerage Systems, Faculty of Environmental Engineering, Wroclaw University of Science and Technology, 50-370 Wroclaw, Poland; [email protected] * Correspondence: [email protected] (F.A.C.); [email protected] (G.J.A.); Tel.: +57-5-3362252 (F.A.C.) Received: 29 March 2020; Accepted: 13 May 2020; Published: 20 May 2020 Abstract: The aim of this research is the detection and analysis of existing trends in the Meta River, Colombia, based on the streamflow records from seven gauging stations in its main course, for the period between June 1983 to July 2019. The Meta River is one of the principal branches of the Orinoco River, and it has a high environmental and economic value for this South American country.
    [Show full text]
  • Urban Flooding Mitigation Techniques: a Systematic Review and Future Studies
    water Review Urban Flooding Mitigation Techniques: A Systematic Review and Future Studies Yinghong Qin 1,2 1 College of Civil Engineering and Architecture, Guilin University of Technology, Guilin 541004, China; [email protected]; Tel.: +86-0771-323-2464 2 College of Civil Engineering and Architecture, Guangxi University, 100 University Road, Nanning 530004, China Received: 20 November 2020; Accepted: 14 December 2020; Published: 20 December 2020 Abstract: Urbanization has replaced natural permeable surfaces with roofs, roads, and other sealed surfaces, which convert rainfall into runoff that finally is carried away by the local sewage system. High intensity rainfall can cause flooding when the city sewer system fails to carry the amounts of runoff offsite. Although projects, such as low-impact development and water-sensitive urban design, have been proposed to retain, detain, infiltrate, harvest, evaporate, transpire, or re-use rainwater on-site, urban flooding is still a serious, unresolved problem. This review sequentially discusses runoff reduction facilities installed above the ground, at the ground surface, and underground. Mainstream techniques include green roofs, non-vegetated roofs, permeable pavements, water-retaining pavements, infiltration trenches, trees, rainwater harvest, rain garden, vegetated filter strip, swale, and soakaways. While these techniques function differently, they share a common characteristic; that is, they can effectively reduce runoff for small rainfalls but lead to overflow in the case of heavy rainfalls. In addition, most of these techniques require sizable land areas for construction. The end of this review highlights the necessity of developing novel, discharge-controllable facilities that can attenuate the peak flow of urban runoff by extending the duration of the runoff discharge.
    [Show full text]
  • Stream Discharge (Streamflow)
    The Importance of Streamflow in California’s Southern Sierra Nevada Mountains Kings River Experimental Watersheds Because 55 to 65 percent of California’s developed water comes from small streams in the Sierra Nevada, it is important to under- stand the role the snowpack has in the distribution and quantity of stream discharge (streamflow). In the southern Sierra, more than 80 percent of precipitation falls December through April. However, owing to the delay in snowmelt, there is a lag in runoff until the spring. At higher elevation sites, the spring melt does not peak until May or even June. This makes mountain water available to California during the summer months. The Kings River Experi- mental Watersheds (KREW) sites demonstrate that precipitation in the form of snow generates greater yearly discharge in a given watershed. The difference in discharge between the KREW Provi- dence site and Bull site is as much as 20 percent per year. C. Hunsaker Research Area Figure 1—KREW’s double flume system. The large flume KREW is a watershed-level, integrated ecosystem project for (background) accurately captures high flows, and the small flume headwater streams in the Sierra Nevada. Eight watersheds at two is successful at measuring lower base flows. study sites are fully instrumented to monitor ecosystem changes. Stream discharge data, just one component of the project, have been collected since 2002 from the Providence site and since 2003 from the Bull site. What is Stream Discharge? Discharge is the amount of water leaving each watershed within the stream channel. It is represented as a rate of flow such as cubic feet per second (cfs), gallons per minute (gpm), or acre-feet per year.
    [Show full text]
  • From the River to You: USGS Real-Time Streamflow Information …From the National Streamflow Information Program
    From the River to You: USGS Real-Time Streamflow Information …from the National Streamflow Information Program This Fact Sheet is one in a series that highlights information or recent research findings from the USGS National Streamflow Information Program (NSIP). The investigations and scientific results reported in this series require a nationally consistent streamgaging network with stable long-term monitoring sites and a rigorous program of data, quality assurance, management, archiving, and synthesis. NSIP produces multipurpose, unbiased surface-water information that is readily accessible to all. Introduction Collecting and Transmitting data are stored in a data logger in Streamflow Information the gagehouse. As part of the National Stream- On a preset schedule, typically flow Information Program, the U.S. The streamflow information every 1 to 4 hours, the streamgage Geological Survey (USGS) operates collected at most streamgages transmits all the stage information more than 7,400 streamgages nation- is stream stage (also called gage recorded since the last transmission to wide to provide streamflow informa- height). This is the height of the a Geostationary Operational Envi- tion for a wide variety of uses. These water surface above a reference level ronmental Satellite (GOES). Many uses include prediction of floods, or datum. Stream stage is measured streamgages have predetermined management and allocation of water by a variety of methods including stage thresholds. When these thresh- resources, design and operation of floats, pressure transducers, and olds are exceeded, the time between engineering structures, scientific acoustic or optical sensors (fig. 1). transmissions to the satellite will research, operation of locks and Stage data are measured at the decrease from 1 to 4 hours to every dams, and for recreational safety and time interval necessary to monitor the 15 minutes to provide more timely enjoyment.
    [Show full text]
  • Pollutant Association with Suspended Solids in Stormwater in Tijuana, Mexico
    Int. J. Environ. Sci. Technol. (2014) 11:319–326 DOI 10.1007/s13762-013-0214-3 ORIGINAL PAPER Pollutant association with suspended solids in stormwater in Tijuana, Mexico F. T. Wakida • S. Martinez-Huato • E. Garcia-Flores • T. D. J. Pin˜on-Colin • H. Espinoza-Gomez • A. Ames-Lo´pez Received: 24 July 2012 / Revised: 12 February 2013 / Accepted: 23 February 2013 / Published online: 16 March 2013 Ó Islamic Azad University (IAU) 2013 Abstract Stormwater runoff from urban areas is a major Introduction source of many pollutants to water bodies. Suspended solids are one of the main pollutants because of their Stormwater pollution is a major problem in urban areas. association with other pollutants. The objective of this The loadings and concentrations of water pollutants, such study was to evaluate the relationship between suspended as suspended solids, nutrients, and heavy metals, are typi- solids and other pollutants in stormwater runoff in the city cally higher in urban stormwater runoff than in runoff from of Tijuana. Seven sites were sampled during seven rain rural areas (Vaze and Chiew 2004). Stormwater has events during the 2009–2010 season and the different become a significant contributor of pollutants to water particle size fractions were separated by sieving and fil- bodies. These pollutants can be inorganic (e.g. heavy tration. The results have shown that the samples have high metals and nitrates) and/or organic, such as polycyclic concentration of total suspended solids, the values of which aromatic hydrocarbons and phenols from asphalt pavement ranged from 725 to 4,411.6 mg/L. The samples were ana- degradation (Sansalone and Buchberger 1995).
    [Show full text]
  • Probabilistic Assessment of Urban Runoff Erosion Potential
    307 Probabilistic assessment of urban runoff erosion potential J.A. Harris and B.J. Adams Abstract: At the planning or screening level of urban development, analytical modeling using derived probability distribution theory is a viable alternative to continuous simulation, offering considerably less computational effort. A new set of analytical probabilistic models is developed for predicting the erosion potential of urban stormwater runoff. The marginal probability distributions for the duration of a hydrograph in which the critical channel velocity is exceeded (termed exceedance duration) are computed using derived probability distribution theory. Exceedance duration and peak channel velocity are two random variables upon which erosion potential is functionally dependent. Reasonable agreement exists between the derived marginal probability distributions for exceedance duration and continuous EPA Stormwater Management Model (SWMM) simulations at more common return periods. It is these events of lower magnitude and higher frequency that are the most significant to erosion-potential prediction. Key words: erosion, stormwater management, derived probability distribution, exceedance duration. Résumé : Au niveau de la planification ou de la sélection en développement urbain, la modélisation analytique au moyen de la théorie de la distribution probabiliste dérivée est une alternative valable à la simulation continue car elle demande un effort computationnel beaucoup moindre. Dans le but de prédire le potentiel d’érosion par des eaux de ruissellement en milieu urbain, un nouvel ensemble de modèles probabilistes analytiques a été développé. Les distributions de probabilité marginales pour la durée d’un hydrogramme dans lequel la vélocité critique de courant dans le canal est dépassée (appelé durée de dépassement) sont calculées en utilisant la théorie de la distribution de probabilité dérivée.
    [Show full text]
  • Leachate Quantities After Closure of a Landfill
    Leachate Quantities after Closure of a Landfill Ali Khatami, Ph.D., P.E., The leachate quantities for SCS Engineers the period of 2010 through 2014 were obtained and Criteria for the solid waste analyzed. The data clearly landfills (40 CFR Part 258 shows a downward trend of or the Subtitle D Federal) leachate quantities following have been around for over 30 closure, as would be years and many municipal expected. Leachate collected solid waste (MSW) landfills from the landfill during have been constructed 2010 was reported on a with lining systems in monthly basis when leachate accordance with the Subtitle quantities after closure were D requirements. However, still high and needed to be very few Subtitle D landfills removed from the facility have been entirely closed for disposal every month. with final covers that include However, leachate quantities a geomembrane barrier layer. rapidly decreased and The significance of the final Glades County Landfill after closing. monthly shipment of leachate covers with geomembrane was no longer necessary; is that percolation of rain Since the landfill was closed in one single construction event, rain water instead, leachate was removed when water into the landfill essentially the storage tank reached a point that stops following completion of the percolation was essentially eliminated almost instantaneously considering the leachate had to be removed and final cover. Assuming the final cover quantities reported. Therefore, the the 20-year time frame the landfill was system remains intact, leachate that data did not have monthly values, but continues to be generated after closure open. It is important to note that the maximum thickness of waste in the clusters of several-months data.
    [Show full text]
  • Distributed Hydrologic Modeling for Streamflow Prediction at Ungauged Basins
    Utah State University DigitalCommons@USU All Graduate Theses and Dissertations Graduate Studies 5-2008 Distributed Hydrologic Modeling For Streamflow Prediction At Ungauged Basins Christina Bandaragoda Utah State University Follow this and additional works at: https://digitalcommons.usu.edu/etd Part of the Civil and Environmental Engineering Commons Recommended Citation Bandaragoda, Christina, "Distributed Hydrologic Modeling For Streamflow Prediction At Ungauged Basins" (2008). All Graduate Theses and Dissertations. 62. https://digitalcommons.usu.edu/etd/62 This Dissertation is brought to you for free and open access by the Graduate Studies at DigitalCommons@USU. It has been accepted for inclusion in All Graduate Theses and Dissertations by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. DISTRIBUTED HYDROLOGIC MODELING FOR STREAMFLOW PREDICTION AT UNGAUGED BASINS by Christina Bandaragoda A dissertation submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY in Civil and Environmental Engineering UTAH STATE UNIVERSITY Logan, UT 2007 ii ABSTRACT Distributed Hydrologic Modeling for Prediction of Streamflow at Ungauged Basins by Christina Bandaragoda, Doctor of Philosophy Utah State University, 2008 Major Professor: Dr. David G. Tarboton Department: Civil and Environmental Engineering Hydrologic modeling and streamflow prediction of ungauged basins is an unsolved scientific problem as well as a policy-relevant science theme emerging as a major
    [Show full text]
  • Introduction and Characteristics of Flow
    Introduction and Characteristics of Flow By James W. LaBaugh and Donald O. Rosenberry Chapter 1 of Field Techniques for Estimating Water Fluxes Between Surface Water and Ground Water Edited by Donald O. Rosenberry and James W. LaBaugh Techniques and Methods Chapter 4–D2 U.S. Department of the Interior U.S. Geological Survey Contents Introduction.....................................................................................................................................................5 Purpose and Scope .......................................................................................................................................6 Characteristics of Water Exchange Between Surface Water and Ground Water .............................7 Characteristics of Near-Shore Sediments .......................................................................................8 Temporal and Spatial Variability of Flow .........................................................................................10 Defining the Purpose for Measuring the Exchange of Water Between Surface Water and Ground Water ..........................................................................................................................12 Determining Locations of Water Exchange ....................................................................................12 Measuring Direction of Flow ............................................................................................................15 Measuring the Quantity of Flow .......................................................................................................15
    [Show full text]
  • Probabilistic Extreme Flood Hydrographs That Use Paleoflood Data for Dam Safety Applications
    Probabilistic Extreme Flood Hydrographs That Use PaleoFlood Data for Dam Safety Applications Dam Safety Office Report No. DSO-03-03 Department of the Interior Bureau of Reclamation June 2003 Contents Page Introduction................................................................................................................................... 1 1.1 Background..................................................................................................................................2 1.2 Objectives....................................................................................................................................4 1.3 Acknowledgements .....................................................................................................................4 Probabilistic Extreme Flood Hydrographs from Streamflow Sampling................................. 5 2.1 General Procedure .......................................................................................................................5 2.2 Example Applications................................................................................................................11 Probabilitic Extreme Flood Hydrographs Using Rainfall-Runoff Models............................ 18 3.1 General Procedure .....................................................................................................................19 3.2 Example Applications s.............................................................................................................20 Reservoir Routing
    [Show full text]