P. H. Burgi P. L. Johnson Engineering and Research Center Bureau of Reclamation September 1971 Bureau of Reclamation TCfiUklIP SPORT STANDARD TITLE PAGE 1. REPORT NO. 3. RECIPIENT'S CATALOG NO. REC-ERC-71-8 I 4 TITLE AND SUBTITLE 5. REPORT DATE I Sep 7 1 Ice Formation-A Review of the Literature and 6. PERFORMING ORGANIZATION CODE Bureau of Reclamation Experience 7. AUTHOR^) 8. PERFORMING ORGANIZATION REPORT NO. P. H. Burgi and P. L. Johnson REC-ERC-71-8 I 9. PERFORMING ORGANIZATION NAME AND ADDRESS I 10. WORK UNIT NO. Engineering and Research Center - Bureau of Reclamation 11. CONTRACT OR GRANT NO. Denver, Colorado 80225 - 13. TYPE OF REPORT AND PERIOD COVERED 12. SPONSORING AGENCY NAME AND ADDRESS .I BRARY Same - 1 3 0 1972 14. SPONSORING AGENCY CODE L 15. SUPPLEMENTARY NOTES Y' Rechi:&: . ?t , Colorado 16. ABSTRACT A review of published literature and Bureau of Reclamation experiences related to ice formation on rivers, reservoirs, and hydraulic structures is presented. The review is directed toward ice problems associated with Bureau of Reclamation projects where flooding or inefficient operation results from ice formation. WORDS AND DOCUMENT ANALYSIS a. DESCRIPTORS-/ "ice jams/ "frazil ice/ ice loads/ "ice breakup/ "flood damage/ "ice-water interfaces/ lake ice/ head loss/ water temperature1 roughness coefficient1 river forecasting/ "hydraulic models/ ice/ ice pressures1 bibliographies b. IDENTIF IERS-1 ice forming/ ice cover/ ice sheet/ ice crystals C. COSATI Field/Group 8L 18. DISTRIBUTION STATEMENT 19. SECURITY CLASS 21. NO. OF PAGE (THIS REPORT) Available from the National Technical Information Service. Operations UNCLASSIFIED 26 Division, Springfield, Virginia 22151. 20. SECURITY CLASS 22. PRICE ! (THIS PAGE) I UNCLASSIFIED I $3.00 ICE FORMATION - A REVIEW OF THE LITERATURE AND BUREAU OF RECLAMATION EXPERIENCE by, P:H. Burgi 7. L. Johnson September 1971 Hydraulics Branch Division of General Research Engineering and Research Cex Denver, Colorado UNITED STATES DEPARTMENT OF THE INTERIOR * BUREAU OF RECLAMATION Rogers C. B. Morton Ellis L. Armstrong Secretary Commissioner ACKNOWLEDGMENT The study was reviewed by T. J. Rhone under the supervision of the Chief, Hydraulics Branch, W. E. Wagner. Appreciation is expressed to the Regional offices for their invaluable assistance in compiling data related to ice problems associated with Bureau facilities. CONTENTS Page Purpose . Conclusions. Recommendations. Literature Review-State of the Art ,...... I. Introduction. II. Formation of River Ice. A. Frazil ice . B. Ice covers . a. Ice cover stability . 3 b. Roughness coefficient for under surface of ice cover. 10 c. Forecasting ice formation and jams. 11 III. Problems Resulting from the Formation of River and Reservoir Ice . 12 A. Ice cover and ice jams. 12 B. Reduction in flow due to ice storage . 12 C. Ice floes causing damage. 13 D. Frazil ice. 13 IV. Remedial Work Around Hydraulic Structures. 14 V. Control of Ice Jams on Rivers. 15 V I. Model Studies. 17 VII. Summary. 18 Review of Ice Problems Associated with Reclamation Facilities . 18 I. Introduction. 18 II. ProblemsUpstreamfrom Reservoirs. 18 III. ProblemsDownstreamfrom Reservoirs. 19 IV. Problemsin NaturalChannelsnot Influencedby Dams. 21 V. Problemsin Canals. 21 VI. Problemson Reservoirsand Dams. 22 VII. EnvironmentalConsiderations. 22 VIII. Ice BoomStudy. 23 IX. Summary. 25 Bibliography . 25 LIST OF FIGURES Figure 1 Developmentof riverfrazil ice. 2 2 Factorsthat affect the rate of coolingof a section of riverwater. 2 3 Definitionsketch. 4 4 Thicknessat upstreamedgeof cover. 4 5 Thickeningof coverfollowingicethrust . 4 CONTENTS-Continued F igu re Page 6 Dimensionless stabilitydiagram. 5 7 Definition sketch. 6 8 Equilibrium of locks under effect of pressure. 6 9 Predominant criterion of equilibrium of locks . 7 10 Critical velocities at the head of pack. 8 11 Equilibrium limit of a cover in the grip of the ice. 9 12 Nomograms for the computations of coefficient n2 .......... 11 13 Indicated water losses-Heart River. 13 14 Stresses acting upon an element of a broken up ice field. 16 15 General relationship between jamming velocity and roughness coefficients. 17 16 Initial ice boom configuration. 23 17 First modification to ice boom. 23 18 Second modification to ice boom. 24 LIST OF TABLES Table Approximate limit of the progression velocity of an ice cover. 8 2 Coefficients of roughness, n2 . 10 3 Values of parameter k . 10 ii '{'" PURPOSE II. Formation of River Ice The purpose of this investigation was threefold. The A. Frazil ice primary purpose was to present a state of the art Frazil ice is defined by the ASCE1 as: review of published work related to ice effect on rivers, * reservoirs, and the operation of hydraulic structures. A "Fine spicules of ice found in water too turbulent second purpose was to review the major icing for the formation of sheet ice. Frazil (derived from conditions that have occurred in recent years on the French word for cinders, which it resembles) Bureau of Reclamation projects. The third purpose was forms in supercooled water when the air to furnish recommendations as to the potential for temperature is far below freezing." research to determine possible means of alleviating or Michel2, 3, discusses the formation of frazil ice (Figure preventing adverse operating conditions caused by ice. 1): "In cold temperatures, the water of a river reaches CONCLUSIONS 320 F on a reach up to a point, shifting with time, where there is a state of supercooling. In this This report has disclosed and summarized the major supercooled zone, there appear throughout the icing problems which have occurred on Bureau of entire cross section of the flow little individual particles of frazil ice which, as they are displaced, Reclamation projects. Various remedial measures are agglomerate to form extremely porous flakes. These discussed in both the literature review and the survey flakes successively come to occupy the surface, and of Bureau of Reclamation experiences. There appears without perceptible augmenting in volume, become to be sufficient need for further research in this area. thickened with new crystals of ice in an exchange The past successes of the limited ice-related research with the exterior." mentioned in the literature review and the multiplicity of the problems experienced by the Bureau of Williams4 indicates the many variables that might Reclamation indicate a need for further study by the affect the rate of cooling of a section of river water Engineering and Research Center. (Figure 2): "The rate of cooling of a section of river water can RECOMMENDATIONS be considered as a complex heat exchange problem which, from a practical viewpoint, will not have an Because of the involvement of various disciplines exact solution." within the Bureau, it is recommended that a Research Study Team be formed to consider ice-related B. Ice covers problems. The objectives of the team will be to review Michel and TriquetS describe the formation of an ice the major icing problems on Reclamation Projects and cover from frazil crystals: to furnish recommendations as to further research needs with regard to methods of alleviating ice "Frazil crystals... agglomerate into flocks which problems on existing facilities, and possible design after a while flow up to the water's sufrace. Water changes on future facilities. imprisoned between the crystals freezes at the surface, and soon the upper parts of the flocks form solid ice crusts (cakes). These ice cakes by hitting each LITERATURE REVIEW other and the banks while moving with the current, STATE OF THE ART have a tendency to adopt a more or less circular shape and develop an edge which stands higher than the I. Intraduction center part; in other words they evolve into the well known form of pancake ice. Pancake ice floes, if they The purpose of this phase of the report is to present a are transported long enough in fluvial stretches, may state of the art review of published work related to ice further develop into ice plates consisting of individual effect on riverflow and on the operation of hydraul ic floes frozen one to another. When the concentration structures. The report is not inclusive with regard to all gets heavy enough, flocks or plates will cover the published material on the subject matter. However, whole width of the section and, being held up by the sufficient work has been included to indicate the banks, constitute an ice bridge from which the ice status, to date, of the subject knowledge. cover progresses upstream." *Numbers refer to references in the Bibliography. OoC T WATER = Q I D, (), 0 ,,::' ,() ~O D 0 I C, 0: 0 0 U' 0 "'"~ I aD DO 0 vO " ,(/ 0 TURBULENT I D () (J ~ I 000 I I 0 0 I () ZONE OF EVOLUTION OF THE FRAZIL ICE LEGEND t,:':"':',! Spicules and discs of ice Frazil flakes Q2ZZ> Floes ICE FORMATION Figure 1, Development of river frazil ice. From Michel? The authors also mention a second type of ice cover formation, namely; border ice. This ice covers forms along the banks of a river in areas of laminar flow: "The top layer adjacent to the bank will go through un d ercooling considerably while the average Amt. of falling snow or rain temperature of water in the middle of the river will Convective cooling still be much above freezing point. Ice will be nL<celated starting right in contact with the colder Evaporative cooling (because more conductive) material of the banks Radiation and this nucleation will propogate on the surface exchange towards the middle of the flow, forming a clear and sol idice sheet." Cousineau6 defines ideal ice formation conditions as those prevailing when: Ground -- "the temperature of the water must be at the freezing point and the atmospheric temperature Heat from fiver bed down to at least zero degree Farenheit or better still Degree of turbulence subzero weather prevailing.