LWI Region 3 Modeling Overview

BOEUF

MACON TENSAS

COCODRIE

Table 3-5 Soil properties used during model calibration and validation.

HYDRAULIC CONDUCTIVITY (INCHES/HOUR)

DRY SOIL - 40% SATURATED INITIAL DEFICIT (INCHES)*

WET SOIL - 100% SATURATED INITIAL DEFICIT (INCHES)*

MAXIMUM DEFICIT (INCHES)

TEXTURE

0.020

3.298

0.000

5.496

Silty Clay

0.010

2.923

0.000

4.872

Clay

0.000

0.000

0.000

0.000

Water

0.300

5.299

0.000

8.832

Silt Loam

0.040

3.787

0.000

6.312

Silty Clay Loam

0.100

4.982

0.000

8.304

Loam

1.200

5.501

0.000

9.168

Loamy Sand

0.040

3.845

0.000

6.408

Clay Loam

{ The encroachment of channel and overbank land cover was reassessed and corrected around Kilbourne and Como gages. { The channel Manning’s n values were revised throughout the major streams and were eventually set to 0.045 during calibration. { Overbank imperviousness from upstream to downstream Como was raised to 80%. { The model was validated using two historical storms. Model results showed strong agreement with observed data in terms of shape and timing. Figure 3-33 shows a calibration example Near Delhi. Table 3-6 details statistical metrics for the Spring 2016 and Summer 2022 storms—a calibration and a validation event, respectively. Table 3-6 Summary of gage calibration and validation statistics.

EVENT

GAGE

RMSE (%)

RSR

PBIAS (%)

r

Kilbourne

1.76%

0.21

0.01%

0.99

Near Delhi

1.94%

0.27

0.51%

0.99

Spring 2016

South Delhi

1.63%

0.27

0.67%

0.99

Como

2.70%

0.31

1.30%

0.97

Kilbourne

2.22%

0.38

1.72%

0.98

Near Delhi

1.98%

0.21

1.31%

0.99

Summer 2022

South Delhi

1.68%

0.22

0.10%

0.98

Como

5.95%

0.35

3.33%

0.97

32

LWI REGION 3 TRAINING

LOUISIANA WATERSHED INITIATIVE