1. Meteorology – Storm Events

2. Knowledge of Precipitation Amounts and Patterns Plan drainage structures –Size temporary culverts to handle storm events during period of operations –Size permanent drainage structure to handle 100 year storms

3. Know Precipitation Amounts and Patterns Time operations –Expose soil during dry periods if possible –Establish vegetative cover as soon as possible –Use native vegetation whenever possible

4. What’s Wrong?

5. Become familiar with precipitation patterns Sources of data –NOAA –NWS –State climatologist Usually at Land Grant University Vast amount of data available on line Ochocos Mountains of Central Oregon

6. National Climatic Data Center http://www.ncdc.noaa.gov/oa/ncdc.html

7. National Weather Service http://www.weather.gov/view/national.php?thumbs=on National Oceanic and Atmospheric Administration's National Weather Service

8. Indiana State Climatologist http://www.agry.purdue.edu/climate/

9. Variation in Precipitation Random Seasonal Proximity to water body (lake affect) Prevailing winds with moisture Topographic

10. Seasonal Variation

11. Proximity to Water Body

12. Prevailing Winds

13. Topographic Affect Rising air cools Dew point reached Water vapor condenses to form clouds Precipitation may occur

14. Cloud patterns induced by passage of air current over mountains Precipitation concentrated on windward side of mountain, and mountain top Tends to be rain shadow on leeward side

15. Fidalgo Island in rain shadow of the Olympic Mountains. Rainforests with up to 200 inches of precipitation on the west side. Rain shadow area northeast of the Peninsula with only one- half (20 inches) of the normal rainfall for the rest of the region.

16. Clearwater 118.5” Coupeville 21.14” Puget Sound Area, Washington

17. Storm Events, 1 st Qtr.

18. Storm Events, 2 nd Qtr.

19. Storm Events, 3 rd Qtr.

20. Storm Events, 4 th Qtr.

21. Monroe County Airport, April 15-16, 1998 15th0953.03 1053.26 1158.00 1253.01 1353.0 1453.04 1553.0 1953.14 2053.12 2153.10 2253.36 2353.17 16th0053.32 0153.22 0253.25 0353.08

22. Some Basic Hydrologic Concepts Weirs are used to measure volume of water flowing past a point.

23. What Happens to Precipitation? Hydrologic cycle P = RO + ET + S, Where, P ≡ precipitation RO ≡ runoff ET ≡ evapotranspiration S ≡ storage

24. Evapotranspiration Loss of water from a given area during a specified time by evaporation from the soil surface and by transpiration from the plants. Supports plant life Reduces water yield

25. Runoff Provides Major Benefits RO = P – ET Moose Creek, Clearfield County, PA (WLH)

26. Where does runoff go to? RO = CI + SRO + SSF + BF, –where, CI ≡ channel interception SRO ≡ surface run off SSF ≡ subsurface flow BF ≡ base flow

27. Where does runoff go to? –CI ≡ channel interception Precipitation falling directly into channel Susquehanna River, Clearfield, PA, (WLH)

28. Where does runoff go to? –SRO ≡ surface runoff or overland flow Precipitation not infiltrating soil Sheet erosion of cropland resulting from surface runoff Source: http://www.agric.gov.ab.ca/agdex/500/72000003.html

29. Where does runoff go to? –SSF ≡ subsurface flow, or interflow Infiltrating precipitation intercepted by hardpan or bedrock before entering groundwater pool

30. Where does runoff go to? –BF ≡ base flow or ground water flow Precipitation entering water table

31. Research results come from experimental watersheds such as:

32. What We’ll Look At Erosion –Impacts of Roads Harvests Water flows –Storm events –Storage Water yield –Amount –Timing Montgemory Reservoir, Clearfield, PA, WLH