1. Calculation of Hydrologic Parameters Using CRWR-PrePro Francisco Olivera, PhD Center for Research in Water Resources University of Texas at Austin

2. Hydrologic Parameters zWatershed yAbstractions and routing method yParameters zStream yRouting method yParameters

3. Watershed Abstractions and Routing Method zAbstractions: precipitation/excess precipitation transformation ySCS curve number method yInitial loss + constant rate loss zRouting: excess precipitation/runoff flow transformation ySoil Conservation Service (SCS) synthetic unit hydrograph

4. Watershed Abstractions Soil properties Precipitation (mm) Excess precipitation (mm) Excess precipitation = f(Precipitation, Soil properties)

5. Watershed Routing Excess precipitation (mm/hr) Runoff flow (m 3 /s) Watershed

6. Watershed Routing Excess precipitation (mm/hr) Runoff flow (m 3 /s) Time Excess precipitation and Runoff flow Runoff flow = f(Excess precipitation, Watershed hydrologic properties)

7. Hydrologic Parameters zWatershed yAbstractions and routing method yParameters zStream yRouting method yParameters

8. Watershed Parameters zArea zAverage curve number zInitial + constant rate loss zLength of longest flow-path zSlope of longest flow path zLag time

9. Elevation Grid

10. Flow Length Downstream

11. Flow Length Upstream

12. Longest Flow-Path

13. Flow Length Downstream to the Watershed Outlet

15. Flow Length Upstream to the Watershed Divide

17. Watershed Longest Flow-Path

19. Slope of Watershed Longest Flow Path

20. Watershed Lag-Time (SCS) t p :lag-time (min) L W :length of longest flow-path (ft) S :slope of the longest flow-path (%) CN :average Curve Number  t: analysis time step

21. Watershed Lag-Time (L/V) t p :watershed lag-time (min) L w :length of longest flow-path (ft) V w :longest flow-path average velocity (m/s)  t: analysis time step

22. Watershed Parameters

23. Hydrologic Parameters zWatershed yAbstractions and routing method yParameters zStream yRouting method yParameters

24. Routing Method

25. Pure-Lag Method zFlow is delayed a fixed amount of time t lag. t lag : flow time in the reach I: inflow to the reach Q: outflow from the reach

26. Muskingum Method zFlow is delayed a fixed amount of time K, and redistributed around its centroid. S: storage in the reach K: flow time in the reach (  t < K <  t/2X ) X: storage parameter I: inflow to the reach Q: outflow from the reach  t: analysis time step

27. Routing Method Flow time (L s /V s ) L s /V s <  t Muskingum Routing L s /V s >  t Pure Lag Routing L s :length of the stream V s :flow velocity in the stream  t: analysis time step

28. Hydrologic Parameters zWatershed yAbstractions and routing method yParameters zStream yRouting method yParameters

29. Pure Lag Parameters t lag :flow time in the reach (min) L s :reach length (m) V s :reach average velocity (m/s)

30. Muskingum Parameters K :flow time in the reach (hr) [Muskingum K] X :storage parameter [Muskingum X] L s :reach length (m) V s :reach average velocity (m/s) n :number of sub-reaches  t: analysis time step

31. Stream Parameters