EFFECTS OF INITIAL ABSTRACTION AND URBANIZATION ON ESTIMATED RUNOFF USING CN TECHNOLOGY<sup>1</sup>

Lim, Kyoung Jae; Engel, Bernard A.; Muthukrishnan, Suresh; Harbor, Jonathan M.

doi:10.1111/j.1752-1688.2006.tb04481.x

Cited by 91 publications

(68 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…CN values can be obtained from tables and they are dependent on the hydrologic soil group (HSG), land treatment, hydrologic condition and land use/land cover. Higher values of CN refer to higher surface runoff while lower values of the Curve Number indicate lower runoff [34,35]. In this study, CN values have been estimated based on the soil texture and land use/land cover.…”

Section: Runoff Depth Estimationmentioning

confidence: 99%

See 1 more Smart Citation

Estimating the Effect of Urban Growth on Annual Runoff Volume Using GIS in the Erbil Sub-Basin of the Kurdistan Region of Iraq

Hameed

2017

Hydrology

View full text Add to dashboard Cite

Abstract:The growth and spread of impervious surfaces within urbanizing catchment areas pose signiificant threats to the quality of natural and built-up environments. Impervious surfaces prevent water infiltration into the soil, resulting in increased runoff generation. The Erbil Sub-basin was selected because the impervious cover is increasing rapidly and is affecting the hydrological condition of the watershed. The overall aim of this study is to examine the impact of urban growth and other changes in land use on runoff response during the study period of 1984 to 2014. The study describes long-term hydrologic responses within the rapidly developing catchment area of Erbil city, in the Kurdistan Region of Iraq. Data from six rainfall stations in and around the Erbil Sub-basin were used. A Digital Elevation Model (DEM) was also used to extract the distribution of the drainage network. Historical levels of urban growth and the corresponding impervious areas, as well as land use/land cover changes were mapped from 1984 to 2014 using a temporal satellite image (Landsat) to determine land use/land cover changes. Land use/land cover was combined with a hydrological model (SCS-CN) to estimate the volume of runoff from the watershed. The study indicates that the urbanization of the watershed has increased the impervious land cover by 71% for the period from 1984 to 2004 and by 51% from 2004 to 2014. The volume of runoff was 85% higher in 2014 as compared to 1984 due to the increase in the impervious surface area; this is attributed to urban growth. The study also points out that the slope of the watershed in the Erbil sub-basin should be taken into account in surface runoff estimation as the upstream part of the watershed has a high gradient and the land is almost barren with very little vegetation cover; this causes an increase in the velocity of the flow and increases the risk of flooding in Erbil city.

show abstract

Section: Runoff Depth Estimationmentioning

confidence: 99%

“…Figure 5 illustrates the CN spatial distribution in the study area for the three examined periods. [34,35]. In this study, CN values have been estimated based on the soil texture and land use/land cover.…”

Section: Runoff Depth Estimationmentioning

confidence: 99%

Estimating the Effect of Urban Growth on Annual Runoff Volume Using GIS in the Erbil Sub-Basin of the Kurdistan Region of Iraq

Hameed

2017

Hydrology

View full text Add to dashboard Cite

show abstract

“…As a result, initial model runs significantly underpredicted runoff in all six of the watersheds. Lim et al (2006a) achieved significant improvements in L-THIA efficiency by lowering the initial abstraction ratio, Ia/S (see equation 1) from the commonly used 20% to the 5% recommended by Hawkins et al (2002). Incorporating this procedure within a second round of L-THIA runs resulted in increased sensitivity to smaller rainfall events, thereby reducing the magnitude by which the uncalibrated models under-predicted runoff, while maintaining the signal of variable soil data resolution.…”

Section: Methodsmentioning

confidence: 99%

Does soil data resolution matter? State Soil Geographic database versus Soil Survey Geographic database in rainfall-runoff modeling across Wisconsin

Mednick¹

2010

Journal of Soil and Water Conservation

View full text Add to dashboard Cite

Developers and users of watershed modeling systems face a tradeoff between increased spatial detail and the amount of time and computing resources needed to build, calibrate, and run models. A number of systems have been developed that can estimate or predict surface water runoff and nonpoint source (NPS) pollution at different scales, under variable soil, land use, climate, and topographic conditions. With advances in data processing and network storage capacity, public data on these variables are increasingly available Does soil data resolution matter? State Soil Geographic database versus Soil Survey Geographic database in rainfall-runoff modeling across Wisconsin A.C. Mednick Abstract: Whether or not the use of generalized, State Soil Geographic (STATSGO) data in place of higher resolution Soil Survey Geographic (SSURGO) data reduces the accuracy of hydrologic and nonpoint source pollution models has thus far been an open question. Comparative studies have yet to reveal a systematic bias in STATSGO-based model outputs on account of their small sample sizes and differences in the models employed. In an effort to determine whether a bias exists, direct runoff was modeled for a hypothetical 24-hour rainfall event, using STATSGO and SSURGO as alternative inputs to a series of standard rainfall-runoff models in nearly 300 contiguous watersheds, spanning most of the state of Wisconsin. The Long-Term Hydrologic Impact Assessment (L-THIA) modeling tool was used for this analysis. Results indicate that there is a negative bias in STATSGO-based runoff over the large majority of the study area and that the degree of underprediction is highest for spatially disaggregated (distributed parameter) models. Runoff was also modeled for daily precipitation in six gauged watersheds and was compared to observed runoff, with SSURGO-based, distributed models typically producing the most accurate outputs. In addition, a series of regression analyses was conducted to determine whether, and in what direction, the STATSGO bias is affected by the percent coverage of land uses that discourage infiltration. The results of these analyses suggest that STATSGO-based, lumped, and partially distributed models, on average, underpredict the relative impact of increasing land-use intensity. These findings indicate that two of the most common approaches to improving the computational efficiency of watershed modeling systems: the use of lower resolution soils data and the lumping of model parameters to larger spatial units of analysis, combine to reduce the accuracy of modeled runoff under current conditions, while simultaneously underestimating the impact of potential future land-use change.Key words: hydrologic group-land use-rainfall-runoff modeling-Soil Survey Geographic (SSURGO) database-State Soil Geographic (STATSGO) database-Wisconsin at higher resolutions. Spatially disaggregated Soil Survey Geographic (SSURGO) data are now available for the vast majority of US counties (for the current status of available SSURGO data across the United...

show abstract

“…The SCS-CN method is essentially based on the water balance equation and on two fundamental hypotheses. The first hypothesis is that the ratio and runoff to effective rainfall corresponds to the ratio of actual potential retention to potential retention; [44][45][46].…”

Section: Methodsmentioning

confidence: 99%

Integrating System Dynamics and Remote Sensing to Estimate Future Water Usage and Average Surface Runoff in Lagos, Nigeria

2018

View full text Add to dashboard Cite

The goal of this study was twofold; first analyze the patterns of water consumption in Lagos, Nigeria and use them in a System Dynamics (SD) model to make projections about future demand. The second part used remote sensing to quantify the contribution of extensive land use/cover change to urban flooding. Land use/cover dynamics over the past decade was analyzed using satellite imagery provided by Landsat Thematic Mapping (TM). Unsupervised classification was performed with false color composite using the Iterative Self-Organizing Data Analysis (ISODATA) technique in a Geographic Information Systems (GIS). The study area was divided into four different land use types during image classification: bare land, built-up area, water bodies, and vegetation. For water demand, two different scenarios of population growth including 5.5% and 2.75 % annual increase were considered. The results showed that water demand dropped by 67% of its current value when losses in distribution were reduced by 20% and population annual growth rate kept at 2.75% over the study period. Bare land and water bodies lost 1.31% and 1.61% of their current area respectively while built-up area grew by 1.11%. These changes in land use/cover changes led to a 64% increase in average surface runoff, mostly attributable to increasing surface imperviousness and the absence of an adequate urban drainage system.

show abstract

EFFECTS OF INITIAL ABSTRACTION AND URBANIZATION ON ESTIMATED RUNOFF USING CN TECHNOLOGY¹

Cited by 91 publications

References 7 publications

Estimating the Effect of Urban Growth on Annual Runoff Volume Using GIS in the Erbil Sub-Basin of the Kurdistan Region of Iraq

Estimating the Effect of Urban Growth on Annual Runoff Volume Using GIS in the Erbil Sub-Basin of the Kurdistan Region of Iraq

Does soil data resolution matter? State Soil Geographic database versus Soil Survey Geographic database in rainfall-runoff modeling across Wisconsin

Integrating System Dynamics and Remote Sensing to Estimate Future Water Usage and Average Surface Runoff in Lagos, Nigeria

Contact Info

Product

Resources

About

EFFECTS OF INITIAL ABSTRACTION AND URBANIZATION ON ESTIMATED RUNOFF USING CN TECHNOLOGY1

Cited by 91 publications

References 7 publications

Estimating the Effect of Urban Growth on Annual Runoff Volume Using GIS in the Erbil Sub-Basin of the Kurdistan Region of Iraq

Estimating the Effect of Urban Growth on Annual Runoff Volume Using GIS in the Erbil Sub-Basin of the Kurdistan Region of Iraq

Does soil data resolution matter? State Soil Geographic database versus Soil Survey Geographic database in rainfall-runoff modeling across Wisconsin

Integrating System Dynamics and Remote Sensing to Estimate Future Water Usage and Average Surface Runoff in Lagos, Nigeria

Contact Info

Product

Resources

About

EFFECTS OF INITIAL ABSTRACTION AND URBANIZATION ON ESTIMATED RUNOFF USING CN TECHNOLOGY¹