Assessment of Agricultural Flood Damages Along the James River in South Dakota Ron S. Beyer Hydraulic Engineer Omaha District US Army Corps of Engineers 2007 Eastern South Dakota Water Conference October 31, 2007 Slide 1
James River AFDAM Study Members James River AFDAM Study Members Ron Beyer Hydraulic Engineer, Hydrology Section, U.S. Army Corps of Engineers, Omaha District Kara Reeves Economist, U.S. Army Corps of Engineers, Omaha District Kevin Adams Hydraulic Engineer, Hydraulics Section, U.S. Army Corps of Engineers, Omaha District Steve Rothe Project Manager, U.S. Army Corps of Engineers, Omaha District Slide 2
James River Background Low gradient 134 ft drop in 474 miles below Sand Lake NWR Slide 3
James River Background Thousands 20 18 16 James River at Redfield, SD USGS 06475000 1997 Observed Hydrograph 14 12 Flow, CFS 10 8 6 4 2 Bank full 10-YR 0 0 10 20 30 40 50 60 Long duration flat peaked flood hydrographs #of Days Slide 4
James River Background James River is a very sinuous prairie stream 60-70% agricultural use in the river valley Slide 5
James River Background The result is significant long duration flooding of croplands Slide 6
James River Feasibility Study Purpose Study issues related to restoration of ecosystem quality while providing flood control and channel restoration benefits Product will be plans for preferred alternatives for aquatic ecosystem restoration and related purposes. Slide 7
AFDAM Model Agricultural Flood Damage Analysis Model Based on AGDAM Model Modified for Omaha District and James River Basin Models historic flow records Estimates Agricultural Damages based on: River Stages and Flows Crop Types/Values/Planting Time Time of Year/ Flood Duration Slide 8
AFDAM Model Straightforward approach for gaged locations with long periods of observed flow record Specifically written for the 1989 USACE Recon Study Previous Application on James River 1989 USACE Recon Study Pipestem/Jamestown Water Control Plan Revision (USACE July 2000) Slide 9
AFDAM Model Based on Period of Record (Gage Data) Concepts and procedures are straightforward Calculates seasonal and duration aspects Direct calculation of replant, alternate crops and double cropping Slide 10
AFDAM Model Components Hydrology Hydraulics Economics Slide 11
Gage Records Hydrology USGS daily flow USACE screened flow records (similar to USGS) Nine gages from ND-SD Stateline to Yankton, SD Divide model into 8 reaches Slide 12
Stateline Columbia Stratford Redfield Huron Forestburg Scotland Yankton 1953-2002 50 Year Record Slide 13
Hydrology Reverse Flow Relationships Columbia Ashton Redfield Power Equation for Negative flow/stage relationships (Q=R*A*B) Slide 14
Hydraulics Stage, ft 1275 1270 1265 1260 1255 Stage vs. Discharge Rating Curve James R. at Redfield, SD Stage vs. flow rating curves Site Specific 1250 1245 0 5,000 10,000 15,000 20,000 25,000 Flow, cfs Slide 15
Stage vs. Flooded Area Curves Over entire reach Stage, ft 1275 1270 1265 1260 1255 Hydraulics Stage vs. Flooded Area AFDAM Reach 4 Ashton to Redfield, SD 1250 1245 0 500 1,000 1,500 2,000 2,500 3,000 Flooded Area, Acres Slide 16
Agricultural Data Crop Unit Values Economics Area vs. % Crop Type Relationships Flood Duration vs. % Crop Loss Recovery Period (dry time) Slide 17
Economics Crop Values SD Crop Budget crop input costs Prices follow Corps Regulation (USDA) Duration and recovery based on County Ext. Office input and NRCS Land Use from NRCS and USGS remote sensing data Slide 18
60 50 Economics % Crop vs Flooded Area Reach 4 % Crop Type 40 30 20 Corn Soybeans S.Wheat W.Wheat Hay 10 0 0 500 1,000 1,500 2,000 2,500 3,000 Flooded Area, Acres Slide 19
Economics Percent Crop Loss 100 90 80 70 60 50 40 30 20 10 0 Percent Crop Loss vs. Flood Duration Reach 4 0 7 14 21 28 35 42 49 Flood Duration, Days Corn Hay Slide 20
Percent Crop Loss 100 90 80 70 60 50 40 30 20 10 Economics Crop Loss Functions Reach 4 Corn Soybeans S.Wheat Hay 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Slide 21
Economics Agricultural Data % Crop Value Loss vs. Time of Year Slide 22
Economics Other Data Infrastructure Damages Can be included as a ratio of Ag Damages Recreational Use Hunting, Fishing, Camping, etc. Slide 23
Economics Model development Remote Sensing Data Application Final Overlay Reach end points Flood profile Land use coverage Slide 24
Economics Model development Final GIS Product Acres flooded by crop type Acres flooded per flood event (2-, 10-, 50-, 100-, 500-year) Based on HEC-RAS 100 Year: delineation Reach 4 Ashton to Redfield Crop Type Acres % Coverage Alfalfa 33.046 1.302 Corn 180.432 7.107 Deciduous Forest 239.846 9.447 Emergent Herb Wetlands 88.413 3.482 Grassland, Hay/Pasture, Small G 1175.286 46.293 High Intensity Commercial / Ind 35.029 1.380 Soybeans 578.13 22.772 Spring Grains, Fallow 31.52 1.242 Winter Wheat 91.134 3.590 Woody Wetlands 85.978 3.387 Totals 2538.814 100.000 Slide 25
Results Expected Annual Damage By reach By year Economics Computes Damages Existing/Baseline conditions With project alternatives Adjusts area-damage relationships Slide 26
140 120 Output EAD Comparison By Reach Expected Annual Damaages in Thousands of Dollars 100 80 60 40 20 Future With Existing Future Without 0 1993 1994 Flood Year 1995 1996 Slide 27
140 120 Output EAD Comparison By Year Expected Annual Damaages in Thousands of Dollars 100 80 60 40 20 Future With Existing Future Without 0 1993 1994 Flood Year 1995 1996 Slide 28
140 120 Output EAD Comparison Expected Annual Damaages in Thousands of Dollars 100 80 60 40 20 Historic Trends Future With Existing Future Without 0 1993 1994 Flood Year 1995 1996 Slide 29
James River FS/EIS Questions? Courtesy SD USGS Slide 30