Hydraulics of Flow in the Kaskaskia River, Illinois
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ISWS/Rl-91/79 REPORT OF INVESTIGATION 91 STATE OF ILLINOIS ILLINOIS INSTITUTE OF NATURAL RESOURCES Hydraulics of Flow in the Kaskaskia River, Illinois by NANI G. BHOWMIK ILLINOIS STATE WATER SURVEY URBANA 1979 REPORT OF INVESTIGATION 91 Hydraulics of Flow in the Kaskaskia River, Illinois by NANI G. BHOWMIK Title: Hydraulics of Flow in the Kaskaskia River, Illinois Abstract: The hydraulics of flow was investigated at two reaches in the Kaskaskia River. The dis- charge varied from 58 to 4000 cfs and the flow frequency varied from 5 to 88 percent. The head loss varied from 0.96 ft/ mile for high flows to 1.98 ft/mile for low flows. The vertical velocity dis- tribution was found to follow a logarithmic distribution. A theoretical distribution predicted the lateral velocity distribution in the bends reasonably well. In all, 79 isovels were developed for all flow conditions. The average value of the energy coefficient was 1.45 for straight reaches and 1.43 for bends. Similarly, the average value of the momentum coefficient was 1.22 for straight reaches and 1.18 for bends. Manning’s roughness coefficient varied from 0.039 to 0.053. During low flows. the river flows through a series of pools and riffles. The median diameter of bed materials varied from 40 mm in the riffle to 0.04 mm in the pool, whereas the Froude number changed from 0.7 to 0.01. During high flows, the effect of the pool and riffle on the flow condition is minimal or non- existent. Reference: Bhowmik, Nani G. Hydraulics of Flow in the Kaskaskia River, Illinois. Illinois State Water Survey, Urbana, Report of Investigation 91, 1979. Indexing Terms: Bed materials, circulation, hydraulic properties, hydraulics, head loss, Illinois, Kaskaskia River, low flow, open channel flow, pools, riffles, river flow, roughness (hydraulic). STATE OF ILLINOIS HON. JAMES R. THOMPSON, Governor INSTITUTE OF NATURAL RESOURCES FRANK H. BEAL, M.U.P., Director BOARD OF NATURAL RESOURCES AND CONSERVATION Frank H. Beal, M.U.P., Chairman Thomas Park, Ph.D., Biology H. S. Gutowsky, Ph.D., Chemistry Stanley K. Shapiro, Ph.D., Forestry Laurence L. Sloss, Ph.D., Geology John C. Guyon, Ph.D., Southern Illinois University William L. Everitt, E.E., Ph.D., University of Illinois STATE WATER SURVEY DIVISION WILLIAM C. ACKERMANN, D.Sc., Chief URBANA 1979 Printed by authority of the State of Illinois (11-79-1000) lM—12-7—46490 CONTENTS PAGE Abstract........................................................................................................................................................... 1 Introduction..................................................................................................................................................... 1 Plan of the report........................................................................................................................................ 2 Acknowledgments...................................................................................................................................... 2 Background analyses ....................................................................................................................................... 2 Flow in straight reaches.............................................................................................................................. 3 Velocity structure ................................................................................................................................. 3 Resistance to flow ................................................................................................................................4 Head loss ............................................................................................................................................. 6 Hydraulic geometry of alluvial channels................................................................................................ 7 Flow around bends ..................................................................................................................................... 8 Superelevation...................................................................................................................................... 8 Velocity structure ................................................................................................................................. 9 Secondary circulation. .......................................................................................................................... 10 Energy dissipation. ............................................................................................................................... 11 Bed topography.................................................................................................................................... 11 Pools and riffles ......................................................................................................................................... 11 Data collection................................................................................................................................................. 12 Hydraulic geometry of the reaches.............................................................................................................. 12 Velocity distribution and water surface profiles........................................................................................... 15 Bed and bank material samples................................................................................................................... 17 Analysis and results ......................................................................................................................................... 20 Geomorphology ......................................................................................................................................... 20 Bed material sizes ...................................................................................................................................... 22 Hydraulic and geometric characteristics of the reaches ................................................................................ 23 Flow frequencies........................................................................................................................................ 29 Water surface profiles................................................................................................................................. 30 Velocity distribution................................................................................................................................... 30 Vertical velocity distribution................................................................................................................. 30 Average velocity in the individual verticals ........................................................................................... 32 Average velocity and bottom velocity.................................................................................................... 34 Velocity structure, isovels..................................................................................................................... 35 Reach1 ........................................................................................................................................... 35 Reach2 ........................................................................................................................................... 53 Flow around bends ..................................................................................................................................... 68 Superelevations .................................................................................................................................... 69 Secondary circulation ........................................................................................................................... 72 Energy and momentum coefficients ............................................................................................................ 74 Roughness coefficient, head loss, and energy dissipation............................................................................. 75 Distribution of unit discharges .................................................................................................................... 80 Turbulence in an open channel.................................................................................................................... 82 Low flow characteristics: Pools and riffles .................................................................................................. 83 Summary and conclusions................................................................................................................................91 References....................................................................................................................................................... 92 Notations......................................................................................................................................................... 94 Appendices...................................................................................................................................................... 96 Hydraulics of Flow in the Kaskaskia River, Illinois by Nani G. Bhowmik ABSTRACT The hydraulics of flow was investigated at two reaches in the Kaskaskia River. Hydraulic data were collected for 58, 1040,