4.5. Analysis of the curve number method for runoff prediction 4.5.1. CN values from NRCS-CN table and least square fitting methods The CN from the NRCS-CN table of values ranged from 59 to 91, while the model-derived CN ranged from 63 to 96 (Table 3). The average abstraction ratio ...
Table 4.30. Estimation of the SCS-UH Parameters UH ParametersExpressionValue Catchment area, A (km2) Given 10.0 Length of main stream, L (m) Given 3000.0 Catchment average slope, S (m/m) Given 0.02 Runoff curve number, CN Given 62 Time lag (h) tL=L0.8(2540−22.86CN)0.714,104CN0.7...
In this model, the curve number (CN) is a key variable which is usually obtained by the look-up table of TR-55. Due to the limitations of TR-55 in characterizing complex urban environments and in classifying land use/cover types, the SCS-CN model cannot provide more detailed runoff ...
For example, coarse-textured sandy soils have larger pore spacing, allowing water to infiltrate quickly relative to fine-textured clay soils. Soils are thus classified into four hydrologic soil groups (HSGs) to infer runoff potential (Table 1)11. HSG-A has the lowest runoff potential (typically...
0.599 0.815 0.841 0.479 0.673 0.737 0.817 0.671 RMSE (mm/ month) 0.01 0.02 0.04 0.07 0.15 0.18 0.2 0.21 0.23 0.26 0.29 0.31 0.31 0.32 0.32 0.36 Table 1. Selected sites for validation and their corresponding hydrologic unit number, goodness of fit and root (R2) mean square error (RMSE...
Shelford's law of tolerance is illustrated by a bell-shaped curve depicting the relationship between environmental factor/factors’ intensity and its favorability for species or populations. It is a fundamental basis of ecology when considering the regularities of environment impacts on living systems, ...
Residential vegetation: Wooded Details Additional structures: Storage Shed Foundation area: 1656 Parcel number: 1911921310032 Lease amount: $0 Zoning description: Residential-Single Family Construction Type & style Home type: SingleFamily Property subtype: Single Family Residence Materials Wood Siding Roof: ...
Accuracies of the retrieved stem curves were assessed using the three accuracy indices, which include the undetected rate, average completeness, and relative bias, as shown in Table 2. In addition, the number of undetected stems, mean bias and RMSE are also presented to show the estimation acc...
The Curve Number approach is an effective, simple and widely used method to estimate surface runoff volume. The revised CN values calculated by using monitoring data from 55 sites in China are considerably different from the CN values acquired from US-based CN value lookup-table. It has been ...
These series of computed C from individual rainfall-runoff events were then used to obtain the mean and median C for each catchment and compared to the table of C values from ASCE manuals (ASCE, 1992, ASCE., 1996). 3.2.2. Curve number The curve number method is used to quantify runoff...