LWI Region 3 Modeling Overview

BOEUF

MACON TENSAS

COCODRIE

Table 3-3 Maximum and initial soil deficits used for infiltration modeling under varying antecedent saturation scenarios (20%, 50%, and 80%) for each soil type.

20% SATURATED INITIAL DEFICIT

50% SATURATED INITIAL DEFICIT

80% SATURATED INITIAL DEFICIT

SOIL CLASSIFICATION MAX DEFICIT

8.9

7.12

4.45

1.78

Silt Loam

0

0

0

0

Water

4.92 8.47 8.23 9.05 6.26 9.77 6.34 5.5

3.94 6.78 6.59 7.24 5.01 7.81 5.07 4.4

2.46 4.24 4.12 2.75 4.52 3.13 4.88 3.17

0.98 1.69 1.65 1.81 1.25 1.95 1.27 1.1

Clay

Silty Clay

Loam

Loamy Sand

Sandy Loam

Silty Clay Loam

Sand

Clay Loam

Table 3-4 Summary of calibration events with associated rainfall intensity, backwater conditions, and initial soil saturation assumptions.

ORDER

EVENT

CHARACTERISTICS

1 2 3 4 5 6

Aug-19

Low flow event. Dry initial condition

Aug-22 Intense rainfall event. Saturated initial conditions

Mar-16 Dec-14 Sep-08 Nov-15

Intense rainfall as well as a big backwater event. Saturated initial conditions

Headwater influence

Small rainfall events. 80% wet initial conditions Small rainfall events. 50% wet initial conditions

The Model Was Calibrated Using Observed Data from the Following Gages:

BAYOU LAFOURCHE: Crew Lake and Alto (stage) BOEUF RIVER: Girard, Alto (USACE), Fort Necessity (stage and flow) BOEUF STATELINE (EUDORA): Stage

OAK GROVE AND SLIGO: Stage only

LEARN MORE: B_4.6 +

Figure 3-25: Bayou Lafourche at Crew Lake calibrated to the August 2022 event (located western side of the Boeuf Watershed).

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LWI REGION 3 TRAINING

LOUISIANA WATERSHED INITIATIVE