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Ice Conditions in Eastern Europe and the Methods Employed to Influence the Formation and Break-Up of the Ice on the Dvina (Daugava) River Kanavins, E

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Ice Conditions in Eastern Europe and the Methods Employed to Influence the Formation and Break-Up of the Ice on the Dvina (Daugava) River Kanavins, E NRC Publications Archive Archives des publications du CNRC Ice conditions in Eastern Europe and the methods employed to influence the formation and break-up of the ice on the Dvina (Daugava) River Kanavins, E. For the publisher’s version, please access the DOI link below./ Pour consulter la version de l’éditeur, utilisez le lien DOI ci-dessous. Publisher’s version / Version de l'éditeur: https://doi.org/10.4224/20331607 Technical Translation (National Research Council of Canada), 1948-12-09 NRC Publications Record / Notice d'Archives des publications de CNRC: https://nrc-publications.canada.ca/eng/view/object/?id=20f7d4a5-2c7f-4272-85cd-7d2119a58dee https://publications-cnrc.canada.ca/fra/voir/objet/?id=20f7d4a5-2c7f-4272-85cd-7d2119a58dee Access and use of this website and the material on it are subject to the Terms and Conditions set forth at https://nrc-publications.canada.ca/eng/copyright READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE. L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site https://publications-cnrc.canada.ca/fra/droits LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB. Questions? Contact the NRC Publications Archive team at [email protected]. If you wish to email the authors directly, please see the first page of the publication for their contact information. Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. Si vous n’arrivez pas à les repérer, communiquez avec nous à [email protected]. NATIONAL RESGARCH LABORATORIES Ottawa, Canada TSCHNICAL TRANSLATION Division of Mechanical Engineering Pages - Preface - 4, Tech, Trans, - TT-85 - Text - 46 Date - 9 December, 1948 Figures - 55 Lab, Order Noo 5424A Tables = 4 File - 12-R4-22 Title: Eisverhaeltnisse in Osteuropa und die Angewandten Massnahmen zur Beeinflussung der Eisbildung und des Eisganges in der mna (Daugava) , By: Edvigs Kanaving , J Reference: Report of the Directorate of Technology and Transport, Division of Hydrology, Riga, 1944, Subject: ICE CONDITIONS IN EASTERN 3UROPE AND THZ METHODS EMPLOYZD TO INFLUTNCE THE FORMATION AND BREAK-UP OF THE ICi3 ON THE DVINA (DAUGAVA)RIVER, Submitted by: Do Bo Nazzer, Translated by: Secreta~y, Do A, Sinclair, Subcommittee on Soil an3 Snow Mechanics, Approved by: J, H, Parkin, Director, Page - (ii) Tech, Transo TT-85 PREFACE The following report was prepared at the re- quest of Admiral Dr. hoco F. S iess, President of the German Naval Meteorological Servicesx$ , for presentation at the con- vention of the Naval ~,!eteorologica~Services in Hamburg, A supplementary section is added, setting forth a plan of the future programme for improving the troublesome ice conditions which mere experienced on the Dvina Hiver after construction of the electrical power plant at Keggum, This programme has been prepared on the basis of the observations described in the present report and the investigatio s of the Depart- ment of Navigable '?daterways and Harbours=f The main part of this report is taken up with a description of the investigation of the ice conditions carried out in the winters of 1941-42 and 1 42-43, and of the rnethodi employed for reducing the depth ice2) in the swift- water section of the Dvina. It should not be regarded as a complete exposition of the material or of the observations and investigations, but merely as an informative statement of the results obtained and the usefulness of the methods employed. After the material contained in the research re- sults has been elaborated it is intended that everything should be made available in a more complete publicationo It is a pleasant duty for the author to express his sincere appreciation to Admiral Dr, hat. Fo Spiess and to the Chief Office of Technology of Latvia for making it pos- sible for him to publish this work. Riga, 19440 n) Die Deutsche Seewarte. xx) D~partementfh Wasserstrassen und Haf en. t) Translator fs Note : The explanation of this term is given on page 3, Page - (iii) Techo Trans, TT-85 TABLE OF COITTEX'TS Page- Preface (ii) General Review of Ice Conditions on the Rivers of Eastern Europe 1 The Investigations of the Latvian Department of Marine on the Dvina up to 1940 5 Estimate of Ice Conditions on the Dvina after Co~npletionof the Keggum Power Plant 8 Investigations of the Department of Marine on the Dvina in the Winters of 1941-42 and 1942-43 15 (a) Formation of the Ice: The Various Types of Ice and their Properties 17 (b) The Freezing of the Swift-Water Section of the Dvina 22 (c) The Quantities of Ice in the Dvina and their Distribution 24 (d) Ground Ice 25 (e) The Reduction of the Drift Ice Driven under the Ice Cover (Tost) 28 The Means Employed for Reducing the Depth Ice 29 (a) Border-Ice Bridges 29 (b) Drift Ice Dams 32 (c) Artificial Production of Depth Ice 34 Possibilities of Obtaining more Favourable Grouping of the Depth Ice in the Swift-Water Section of the Dvina with the Aid of Ice Bridges 36 Page - (iv) Techo Trans TT-85 Table of Contents (contfd) Page VII Evaluation of Research Results; Conclusions 39 VIII The Inadequacy of the Previous Methods; The Future Program for Improving the Troub.lesome Ice Conditions on the Dvina Since Completion of the Keggum Power Plant 41 (a) Inadequacy of the Maximum Program Drawn up by the Swedish Firm 41 (b) The Proposed Interim Program for Decreasing the Break-Up Difficulties on Lake Keggum 43 IX Concluding Remarks 45 Page - 1 Tech0 Trans, TT-85 ICE CONDITIONS IN ZASTSRN EUROPE AND THE METHODS EMPLOYED TO INFLUENGE THX FORMATION AND BREAK-UP OF THZ ICE ON THZ DVINA (DAUGAVA)RIVER I GENERAL REVIEW OF ICE CONDITIONS ON THE RIVZRS OF EASTERN EUROPE Because of the troublesome ice conditions on the rivers of Eastern Europe the design, construction and operation of various hydro-electrical plants is considerably more complicated than in the countries of Western Europe, Hence, owing to the increased economic exploitation of water resources in the eastern countries, more and more attention is being paid to this problem, and special observations and investigations are being undertaken in order to discover ways and means of mitigating the destructive effects of the ice 0 The course of the phenomena is in general very complex and has thus far been the object of little research, It depends on a great many different factors of which the following are the most important: 1, Climatic factors, which determine the / length of the winter, or ice period, and the thickness of the ice cover; 4 2, Geographical factors, in which the geo- graphical zone and compass direction of the riverqs course come under consideration; J 3. lVIorphologica1 factors, which characterize the river bed, the flow, etc, The severity of the ice conditions depends mainly on the climate, In places where the winter is relatively long and severe the ice conditions are more troublesome, The thickness of the ice cover normally in- creases from south to north, Yet in the rivers of Eastern Europe, even in the far north, it does not exceed 1020 metres, It is noteworthy that the ice cover in the rivers of Siberia is considerably thicker than this, The geographical situntion of the river is closely related to the climatic conditions, The zone in which it lies and its direction of flow are of great im- Page - 2 Tech, Trans, TT-85 portance for the ice conditions, If the river flows from north to south (Volga, Don, Dnieper)t) the processes of ice formation and break-uptt ) follow a pelat ively normal course. The lower reaches of the river become free of ice before the upper reaches, Conditions are altogether different if the river flows from south to north (Northern Dvina, Pechora, etc,), In such rivers the break-up usually attains the pro- portions of a natural catastrophe, It begins, as a rule, in the upper reaches of the river while there is still a firm ice cover in the lower ones, Immense ice jams form which result in a sudden increase in the water level and disastrous floods, In such cases the masses of water, seeking a way around the ice jams, demolish the banks, destroy settlements, tear open new arms of the river, carry away sand from the old river bed, damage man-made structures; embankments, etc . In the rivers which flow from east to west (~vina,Memel, Neva, Svir, etc,) the ice conditions may vary widely, In cases where, due to unfavourable meteorological conditions, the break-up begins in the upper reaches of the river special difficulties may arise which demand great expenditures of effort and material on the part of the authorities and or- ganizations who must battle with the ice, The morphology of the river is a very important factor determining the nature of the ice conditions at dif- ferent points, In places where the gradient changes suddenly, or where the river takes many turns and is of unequal width, or where there are a great many shallow places and islands, dangerous ice jams which are difficult to eliminate usual-ly form during the break-up, In the countries of Western Europe, where the rivers are rewlated, this circumstance is not so t) Translator's Note: Insofar as possible the spelling of the geographical names has been taken from the Encyclopaedia Britannica, Translatorfs Note: Two terms are used here, "~isaufbruch", which would refer to the spontaneous breaking up of the ice cover into floating masses, and "Eisgangn, describing the passage of these masses down-stream with the cur- rent, Subsequently the latter term appears to denote both these processes and the translator has therefore just employed the one term "break-up", Page - 3 Tech.
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