Cooper Creek Catchment Flood Rules of Thumb This Guide Has Used the Best Information Available at Present
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QueenslandQueenslandthethe Smart Smart State State How to use this guide: Cooper Creek Catchment Flood Rules of Thumb This guide has used the best information available at present. It is intended to help you assess what type of flood is likely to occur in your area and indicate what amount of feed you might expect. You may wish to record your own flooding guides on the map. You can add more value to this guide by participating in an MLA EDGEnetwork Grazing Land Management (GLM) training package. GLM training helps you identify land types and flood zones and to develop a grazing management plan for your property Amount of rain needed Channel Country Flood descriptions Estimated Summer Flood Pasture Growth in the Channel Country Floodplains. Frequently flooded plains Occasionally flooded plains Swamps and depressions for flooding Flood type Description Land Hydrology Pasture growth Isolated Systems which supports: Flood type (C1) (C2) (C3) Widespread Widespread Rain 100 mm Localised Rain “HANDY” to flooded “GOOD” flood Then increases (kg DM/ha of useful feed) (kg DM/ha of useful feed) (kg DM/ha of useful feed) 95 “GOOD” flood Good Good floods are similar to handy floods, but cover a much higher C1, C3, C2 Flooded across most of 85 - 100% of to proportion of the floodplain (75% or more) and grow more feed per floodplains potential cattle Good 1200-2500 1500-3500 4500-8000 90 area than a handy flood. 80-100% inundation numbers 85 IF in 24-72 hrs Handy Handy floods occur when the water escapes from the gutters, C1, C3 Pushing out of gutters across 45 - 85% of Handy 750-1500 100-250 3500-6500 80 PRIOR, rains of (or useful) connecting up to form the large sheets of water. It can cover up to floodplain and into swamps and potential cattle Gutter 400-1200 No growth 2000-4500 less than 50% of the floodplain. There is a large pasture response from these depressions numbers These are based on flood 75 Isolated Rain floods but yield and area is less than a good flood. 50-60% inundated 50mm fall Channel 250-750 No growth 1200-2500 height and flooding of 70 infrastructure Together = Gutter Gutter floods occur when the water escapes from the main channels C1 Pushing out of channels into 5 - 25% of 65 and spills over to the many small waterways (gutters) that flow from gutters potential cattle “GUTTER” 60 PLUS the main channels. These floods promote growth of a good body of 5-15% inundated numbers Flood Definitions flood herbage and grasses along the gutters. “How Often” are FLOOD rains received? “How Often” are FLOOD rains received? 55 Proportion (%) of years that rainfall in 24 hrs is at least Proportion (%) of years that rainfall in 24 hrs is at least BoM Channel Country 50 Widespread Rain Channel The major channels run and water just spills over banks but does not C1, limited to Major channels breaking banks 5 - 15% of escape to the surrounding floodplain. Limited feed grows along channel <5% inundated potential cattle 100 mm 75 mm Location 100 mm 75 mm Location 45 Major Good margins of major channels. margins numbers 19 42 Muttaburra 9 37 Prairie 40 Handy 16 28 Aramac 15 39 Torrens Creek 35 What are the Channel Country floodplain land types ? Camoola Park 7 20 Lake Galilee Moderate Gutter 30 12 30 Minor Channel C1: Frequently flooded alluvial plains with braided channels, often with deep and fast flowing water in major channels. 1 7 Tangorin 25 Amounts of rain do not by themselves C2: Occasionally flooded, flat alluvial plains , generally with shallow and slow flowing water. This land zone is usually the furthest 20 determine the Channel Country type of David P helps from the major channels, but includes higher areas of floodplains. These are based on land 15 flood. The Thomson River catchment has large areas C3: Poorly drained swamps and depressions on alluvial plains of intermittent flooding, with variable water speed and depth, types, pasture growth and 10 rainfall of Amount Other important factors that modify the type of of heavy Mitchell grass downs which need a lot of percent of potential cattle generally associated with the outer lying channels. 5 flood are duration and time of year. rain to run enough water for a flood numbers that could be carried Floods recorded in the Cooper “How Often” are FLOOD rains received? Year Flood type Flood events in the Cooper between 1882 and 2006 1882 Handy Proportion (%) of years that rainfall in 24 hrs is at least 1885 Handy (estimated from historical flood records from Windorah) Legend 1887 Handy 100 mm 75 mm Location 1890 Good 17 Good floods 7 Channel floods 1892 Handy 14 36 Longreach The top part of the catchment is the desert uplands. There is a lot of sandy spinifex 1893 Good (once every 7 years) (once every 18 years) Localities 1894 Handy and rocky outcrop country which only needs a few inches (>50 mm) of rain 1898 Good 0 5 Tocal 1903 Gutter to run water. Eight to ten inches of rain (200mm - 250mm) up there will produce a flood 1906 Good 5 16 Stonehenge © Paul Jones at Stonehenge. © David P helps Three-way split 1907 Good 1908 Handy 1910 Handy Lake Buchanan (above) and 1911 Gutter 18 Gutter floods River height guages 1913 Gutter The Longreach river height guaging station does not record all water in the upper catchment. There is a lot of hard country Lake Dunn (below) are ephemeral 1917 Handy (once every 7 years) lakes which rarely contribute water 1918 Handy I- that drains south-east from Winton into the Darr River, Vergemont Creek and others and then into the Thomson 1920 Handy ed to what is measured at Longreach to the Cooper system ^_ BoMQ (Qld) 1921 Gutter downstream of Longreach. These probably contribute about 30% extra flow compar 1922 Good 1923 Handy TORRENS CREEK 1924 Handy ^_ DWLBC (SA) 1925 Channel Start watching for a flood with reports of 2 - 4 inches (50 - 100 mm) generalised rain around Muttaburra, Torrens Creek 1928 Channel PRAIRIE 1930 Channel r and Aramac #* 1931 Gutter NRM&W (Qld) 1932 Gutter © Paul Jones 1933 Handy 1934 Handy Watercourses 1935 Channel 1936 Handy 38 Handy floods on average, there is a flood 1937 Gutter (once every 3 years) every 1.6 years in the Cooper 1938 Gutter The Dry Main rivers 1940 Good A L Swamp I 1941 Good EK B C E L E R A C B 1943 Gutter C C R A E K E N S F N E T R K 1944 Good E A Y © David Phelps E L T C L I Important creeks 1945 Gutter M O VE R It is useful to track the flood progress W E 1946 Handy C C E “How Often” are FLOOD rains received? K WHITEWOOD R R K E E K E 1949 Handy I- E E E from Muttaburra onwards K E E K Cauckingburra Swamp 1950 Good Proportion (%) of years that rainfall in 24 hrs is at least R R B C C U OOD C A R L Other creeks 1951 Good ROCKW R EEK L S R O E E C Lake Buchanan 1953 Handy R K 100 mm 75 mm Location P K E R AIRI C 1954 Handy David Phelps H E CR R EK T EEK E E LUBRA E R 1955 Good CR K C 6 14 Opalton T EE R K O K P 1956 Handy W E E Waterbodies The 2006 flood at Longreach was moderate in size, E 1957 Handy TAN GORIN R 11 25 Morella R C H S 1961 Handy I L N peaking at 16.4 feet (5 m), partly covering the 16 km L E R 1963 Good C R Maneroo R 2 4 O T 1964 Run wide floodplains. A handy flood resulted in the Cooper E lake E 1966 Handy LE C K ORNVIL R EEK 1967 Handy TH 1968 Handy 1969 Run flood plains 1970 Gutter Vergemont & Maneroo Creeks & the Darr River can contribute a lot of water to the Thomson. The Thomson can bottleneck at Stonehenge, this causes CU 1971 Good LLO I- DEN CREEK 1972 Handy water to back up and spread out further L © Bob Young A 1973 Handy N swamp D K 1974 Good S E B E 1975 Run O R EK R C E O R R C 1976 Handy U T G E 8-10 inches (100-150mm) of rain at Stonehenge will produce a small, fast flood (a 'splash flood') which covers the high country first but runs out H L If the water is over the old bridge at Longreach, 1000 H O 1977 Handy BA C B Elevation (m) N S GA R R LL A CRE E E and backed up to Muttaburra, then stock L D 1978 Channel of steam by the bottom end of Tanbar E E N K K S U r H 1979 Handy T Lake Galilee movements need to be planned 700 1980 Gutter K 1981 Gutter EE CORNIS H CR *# 500 1982 Channel A quick 2 inches (50 mm) of rain will run Vergemont Creek. At first it runs red but with big rains it will run clear. The Vergemont area has tighter W RE R “How Often” are FLOOD rains received? 1983 Gutter ES TERN C EK E K E 1984 Handy MUTTABURRA E D alluvial soils and grows good grass cover with some herbage. The Thomson area nearby mainly grows herbage.