Water Conference 2016: Building a Secure Water Future Darr Agricultural Center, Missouri State University Springfield, Missouri October 20, 2016 Water and Climate: Recent Flood Trends in Ozark rivers Robert T. Pavlowsky Department of Geography, Geology, and Planning Ozarks Environmental and Water Resources Institute Missouri State University March 2008 Flood 8 billion dollars in flood damage/year in the USA -Increasing trend due to climate change, James River at Hootentown population/development, and/or government policies Stone County, Missouri Ozark Highlands Land use and conservation practices have generally improved since the early 1900s. Urban areas are limited in the Ozarks. Therefore, climate is the main driving force for floods at the basin-scale Greene County, MO- Agricultural Census 500000 Land in Farms (acres) 400000 Population 300000 200000 100000 0 1840 1860 1880 1900 1920 1940 1960 1980 2000 Census Year QBJECTIVES (1) Has river flooding increased in the Ozarks over the past 30 years? (2) What are some of the climate factors involved? (3) How to think about climate-driven flood risk? Management intervention actions for climate-change affected rivers • Storm water and sediment • Floodwater storage management management • Channel reconfiguration • Fish passage • Dam removal/retrofit • Flow modifications for • Floodplain restoration dams • Water quality • Bank Stabilization management • Riparian vegetation • Land acquisition management Palmer et al. (2008) Frontiers in Ecology • In-stream habitat and Environment 6(2):81-89. improvements Climate change “Drivers” • Atmospheric composition (years to decades) – CO2, volcanic dusts – Years to decades • Earth-Sun relationship (Milankovitch Cycles) – Eccentricity- orbit shape 100k and 400 yrs – Obliquity- axis tilt angle 41k yrs – Precession- axis wobble 22k yrs (19-24K) • Plate Tectonics (millions of years) – Elevation, ocean basin size, continental location Global temperatures are rising since 1970… 2015 is hottest year on record globally. Only 1 hottest year not in 2000s (1998) Missouri News-Leader Article (2013) 5 degree F warmer hardiness zone shifted north about 150 miles in a 20 year period. Landscapers and farmers are changing plant selections and planting habits as the state slowly warms up. Pat Guinan, Extension/State Climatologist February 2011 1985-> wetter Predicted trend of more intense rainfall in the Ozarks NOAA, CMIP3 model, K. Hayhoe Also: Mallackpour & Villarini (2015) In, Nature Climate Change-Letters 1) Increase in extreme rainfall at Ozark gages 2) Mainly in Spring and Fall Pavlowsky, Owen, & Bradley, 2016. Historical rainfall analysis for the Big Barren Creek Watershed, southeast Missouri (1955-2015), Report to the US Forest Service, Rolla, MO. Big Barren Ck: No. of days with rainfall >1” Big Barren Ck: No. of days with rainfall >3” (8x increase in frequency last 10 years) 10 days in 10 years --------------------------- 6 days over 50 years ---------------------------- Upper Mississippi Valley Flood records from the last 10,000 years indicate big swings in flood regime characteristics – Large variations in flood magnitude caused by changes of 1-2 degrees C in temperature and 5-20% of mean annual precipitation. – +/- 30% variation in “bankfull” floods during Holocene Epoch compared to present-day. – Variations are not always random, but follow climate- forced trends. Knox, 2000. Quaternary Science Reviews 19:439-457 Millennial time-scale variations in climate driven hydrology and flooding trends Ozarks: Speleothem rings and old floodplain soils= 1,000 to 4,000 year cycles Upper Midwest: Wisconsin rivers 4000 years Midwest US climate trends Easterling and Karl (2001) & Union of Concerned Scientists (2009) • Historical hydro-climate regime: – Increase in ppt by 20% including more intense events. – Canada: 5-15% increase in annual rainfall resulted in 1.5-2 times increase in 10 yr RI floods. (Ashmore and Church, 2001) • Future climate predictions: – 10-20% increase in ppt & wetter in winter – 5 degree C increase in temp by 2100 Flooding has generally been increasing in the Midwest since 1960s (Blue=increase) National USGS gage network: Average flood peak discharge for a given year (2.33 yr flood) Increase in overbank flood magnitude and variability since 1973? • From: Xiaodong Jian, David M. Wolock, Harry F. Lins, and Steve Brady, Streamflow of 2012—Water Year Summary, U.S. Geological Survey, Reston, Virginia, May 2013. Some gages indicate a recent trend in larger floods… Gage record since 1956 (59 years) 4 largest flood peaks since 1993. 5 when water year ending September 30th is included (not including 1909) 20 ft --- The Ozarks… 15 ft --- But not all gages show this trend… Methods- Maximum annual series analysis USGS software PeakFQ was used to conduct Compare peak flood discharges calculated flood frequency analysis on each time series. for different recurrence intervals (RI) between two periods: Pearson Type III frequency distribution Bulletin 17B (1982) http://water.usgs.gov/software/PeakFQ/ 1) Recent period: 1986-2015 2) Past period: 1956-1985 Using only annual peak series, not all floods that occur in a given year 4 overbank floods in two weeks! 1.5-year flood (fills channel to bank-top) • Channel stability and sediment transport 10-year flood • Geomorphic Effectiveness – Bedload supply and transport – Meander belt & planform 100-year flood (can inundate the valley floor) • Flood risk and loss management (“100-yr Floodplain”) • Riparian corridor ecology and land use Rivercut Golf Course, Springfield, Mo. (Mar 2008) Ozark Highlands- What are the recent flood trends? 23 USGS gage sites: distributed along a East-West gradient across the Ozarks Basin Map Drainage Relief Land Use (% of drainage area) Gage Location (23 Gages) Slope No. Area (ft) (sq. mi) (ft/mi) (high to low) Forest Agriculture Urban 1 Cedar Creek near Pleasant View, MO 420 4.8 604 33 63 4 2 Little Piney Creek at Newburg, MO 200 14.0 804 71 24 5 3 Gasconade River at Jerome, MO 2,840 3.0 1,414 60 35 5 4 Meramec River near Steelville, MO 781 6.3 882 67 28 5 5 Meramec River near Sullivan, MO 1,475 5.0 1,010 74 21 5 6 Bourbeuse River at Union, MO 808 2.8 882 58 36 7 7 Big River near Richwoods, MO 735 4.6 1,279 73 21 6 8 Big River at Byrnesville, MO 917 3.4 1,427 74 20 6 9 Meramec River near Eureka, MO 3,788 3.4 1,502 71 24 6 10 James River near Springfield, MO 246 6.5 679 42 50 8 11 James River at Galena, MO 987 4.8 905 34 52 14 12 North Fork River near Tecumseh, MO 561 8.3 1,171 68 29 3 13 Jacks Fork at Eminence, MO 398 9.5 1,059 77 19 4 14 Current River at Van Buren, MO 1,667 5.9 1,279 81 16 4 15 Current River at Doniphan, MO 2,038 4.8 1,443 83 14 3 16 Eleven Point River near Bardley, MO 793 10.1 1,164 68 28 4 17 Spring River near Waco, MO 1,164 6.1 1,020 15 79 6 18 Shoal Creek above Joplin, MO 427 8.3 813 31 61 8 19 Spring River near Quapaw, OK 2,516 5.9 1,138 20 71 9 20 Elk River near Tiff City, MO 851 8.1 1,099 51 41 8 21 Illinois River near Watts, OK 630 8.5 1,204 29 53 17 22 Illinois River near Tahlequah, OK 950 5.3 1,450 38 48 14 23 Baron Fork at Eldon, OK 312 13.4 1,292 51 44 5 Flood Changes for 23 Ozark River Gages Change Qpk 1.5-yr RI 10-yr RI 100-yr RI (diff/past x 100%) (67%) (10%) (1%) > +50% 13 22 + 20 to 50% 39 31 22 + 10 to 20% 17 13 26 +10 to -10% 31 39 26 -10 to -20% 13 4 4 % increase 56 57 70 (cfs) E ffect of land use change on floods on change use of land ffect 1.5-yr RI flood Change 10-yr RI flood Change 100-yr RI flood Change 1.5-year Flood 1 Cedar Creek near Pleasant View, MO 2 Little Piney Creek at Newburg, MO 3 Gasconade River at Jerome, MO 4 Meramec River near Steelville, MO 5 Meramec River near Sullivan, MO 6 Bourbeuse River at Union, MO 7 Big River near Richwoods, MO 8 Big River at Byrnesville, MO 9 Meramec River near Eureka, MO 10 James River near Springfield, MO 11 James River at Galena, MO 12 North Fork River near Tecumseh, MO 13 Jacks Fork at Eminence, MO 14 Current River at Van Buren, MO 15 Current River at Doniphan, MO 16 Eleven Point River near Bardley, MO 17 Spring River near Waco, MO 18 Shoal Creek above Joplin, MO 19 Spring River near Quapaw, OK Flood Change 20 Elk River near Tiff City, MO (Qpk x RI ) 21 Illinois River near Watts, OK 22 Illinois River near Tahlequah, OK >50% increase 23 Baron Fork at Eldon, OK +20-50% increase +10-20% increase No change Decrease 10-year Flood 1 Cedar Creek near Pleasant View, MO 2 Little Piney Creek at Newburg, MO 3 Gasconade River at Jerome, MO 4 Meramec River near Steelville, MO 5 Meramec River near Sullivan, MO 6 Bourbeuse River at Union, MO 7 Big River near Richwoods, MO 8 Big River at Byrnesville, MO 9 Meramec River near Eureka, MO 10 James River near Springfield, MO 11 James River at Galena, MO 12 North Fork River near Tecumseh, MO 13 Jacks Fork at Eminence, MO 14 Current River at Van Buren, MO 15 Current River at Doniphan, MO 16 Eleven Point River near Bardley, MO 17 Spring River near Waco, MO 18 Shoal Creek above Joplin, MO 19 Spring River near Quapaw, OK Flood Change 20 Elk River near Tiff City, MO (Qpk x RI ) 21 Illinois River near Watts, OK 22 Illinois River near Tahlequah, OK >50% increase 23 Baron Fork at Eldon, OK +20-50% increase +10-20% increase No change Decrease 100-year Flood 1 Cedar Creek near Pleasant View, MO 2 Little Piney Creek at Newburg, MO 3 Gasconade River at Jerome, MO 4 Meramec River near Steelville, MO 5 Meramec River near Sullivan, MO 6 Bourbeuse River at Union, MO 7 Big River near Richwoods, MO 8 Big River at Byrnesville, MO 9 Meramec River near Eureka, MO 10 James River near