LWI Region 3 Modeling Overview

BOEUF

MACON TENSAS

COCODRIE

3.6 WATERSHED-SPECIFIC DESCRIPTION 3.6.1 Boeuf a. Hydrologic Model (HEC-HMS) Boeuf Watershed – HEC-HMS Modeling Summary

Overview { HEC-HMS was used to model the Arkansas headwaters of the Boeuf Watershed, providing inflow data for the Boeuf 2D ROM HEC-RAS model. { Detailed modeling methodology and results are documented in the Boeuf Report.

LEARN MORE: B_HMS_APPENDIX_1 +

WATERSHED CHARACTERISTICS

MODELED AREA: 572 square miles (sq. mi.).

CONFIGURATION: 70 subbasins and 80 reaches; see (Figure 3-16).

LEARN MORE: B_HMS_APPENDIX_2.1.1 +

Figure 3-16: Boeuf River-Arkansas HEC-HMS delineation and Eudora Gage location.

Rainfall-Runoff Transformation

Reach Routing Methods

Loss Method { Approach: Deficit and Constant method to simulate initial abstraction and infiltration losses. { Detailed procedures available in the Soil Data–Parameter Selection section and: LEARN MORE: B_HMS_ APPENDIX_2.1.4 +

Baseflow Representation { Method: Linear Reservoir used to simulate subsurface water contribution post-infiltration. { See the link below for more information: LEARN MORE: B_HMS_ APPENDIX_2.1.6 +

METHOD: ModClark transform used to convert precipitation to runoff hydrographs at each subbasin outlet. APPROACH: Accounts for subbasin specific characteristics. LEARN MORE: B_HMS_ APPENDIX_2.1.5 +

MODPULS METHOD : Applied to areas with significant overbank storage; based on 1D HEC-RAS hydraulics. MUSKINGUM-CUNGE METHOD : Used for channelized

reaches; routing based on channel slope, roughness, and length. LEARN MORE: B_HMS_ APPENDIX_2.1.7 +

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LWI REGION 3 TRAINING

LOUISIANA WATERSHED INITIATIVE