College of Engineering/ College of Agricultural and Life Sciences

1. Historic Irrigation in the Snake River Plain, prior to 1900 ESHMC: Validation of the ESPAM2.0 Model, Historic Scenario Input College of Engineering/ College of Agricultural and Life Sciences Department of Biological and Agricultural Engineering

2. Outline • Estimating Irrigation prior to 1900 • Estimating Unregulated Flow • Modeling Irrigation in 1880-1900

3. Estimating Irrigation prior to 1900 Bingham County Sources: History of Irrigation Development in Idaho, Lewis, 1924 Pioneer Irrigation, Upper Snake River Valley, 1955

4. Estimating Irrigation prior to 1900 Bonneville County Sources: History of Irrigation Development in Idaho, Lewis, 1924 Pioneer Irrigation, Upper Snake River Valley, 1955

5. Estimating Irrigation prior to 1900 Jefferson County Sources: History of Irrigation Development in Idaho, Lewis, 1924 Pioneer Irrigation, Upper Snake River Valley, 1955

6. Estimating Irrigation prior to 1900 Madison County Sources: History of Irrigation Development in Idaho, Lewis, 1924 Pioneer Irrigation, Upper Snake River Valley, 1955

7. Estimating Irrigation prior to 1900 Henry’s Fork and Falls River Wood River 50,000 acres prior to construction of the big projects Sources: History of Irrigation Development in Idaho, Lewis, 1924 Pioneer Irrigation, Upper Snake River Valley, 1955

8. Madison County Estimating Irrigation prior to 1900 Findings 1) Irrigation Started around 1879 2) Water Rights filed before actual diversions began 3) The ‘Panic of 93’ led to the end of irrigation expansion 4) Around 1900 sugar beet factories Sources: History of Irrigation Development in Idaho, Lewis, 1924 Pioneer Irrigation, Upper Snake River Valley, Carter, 1955 Irrigated Eden, Fiege 1999

9. Estimating Unregulated Flow • 415-year Tree-Ring Record • Flow at Jackson Lake • Flow at Palisades • Flow at Heise Source: Wise, Erika K. (2010). “Tree ring record of streamflow and drought in the upper Snake River.” Water Resources Research, vol. 46: W11529.

10. Estimating Unregulated Flow-Annual Source: Wise, Erika K. (2010). “Tree ring record of streamflow and drought in the upper Snake River.” Water Resources Research, vol. 46: W11529.

11. Estimating Unregulated Flow-Monthly Monthly Estimation Procedure 1) Rank Years by Annual Flow (1928-1997) 2) Calculate Average Monthly Hydrograph per category 3) Calculate standard deviation per category 4) Fm = (Fa – Favga)/STDavga *STDavgm+Fmavg) Validate r² = 0.82 Calibrate r² = 0.80 Validate r² = 0.87

12. Modeling Monthly Recharge 1880-1900 SD-SRPM (System Dynamics Snake River Planning Model) Model Assumptions 1) No minimum flow requirements 2) No reservoir storage 3) No groundwater pumping 4) Linear increase in irrigation demand from 1880-1900 5) 75% of current demand

13. Modeling Monthly Recharge 1880-1900 SD-SRPM (System Dynamics Snake River Planning Model) 1881 1900 1910 1920 1890

14. Modeling Monthly Recharge 1880-1900 SD-SRPM (System Dynamics Snake River Planning Model) Findings 1) Correctly identify historic shortages between 1900-1905 2) Irrigation induced ESPA discharge (≈ 5 kaf) below Milner 3) Irrigation impact constant below Milner

15. Some Thoughts • How to validate • 1) SD-SRPM allows estimation of monthly recharge • 2) Should validation be at a monthly timestep? • 3) Possible uses of a Systems Model for ESHCM & IDWR • Estimate Recharge (historic-availability) • Estimate Recharge (land-use changes)

17. Questions?