GB Poschmann,A. S.; Klassen, K. E.; *-) Klugman,M. A. s614 SLOPESTABILiTY STUDYOF THE SOUTHNATION RIVER AND PORTIONSOF THE OTTAWA RIVER GB 448 .s634 'iliiil iltfiql[U [iryfitiil ilfiimlii' Ontario GeologicalSurvey MiscellaneousPaper Il2 SlopeStability Study of the SouthNation River and Portionsof the OttawaRiver by A.S. Poschmann,K.E. Klassen, M.A. Klugman,and D. Goodings A project funded by the South Nation River Conservation Authority, the Federal Depart- ment of Regional Economic Expansion, and the Ontario Ministry of Natural Resources. 1983 \ a\.' Hon.Alan W. Pope Ministryof Minister Natural W.T Foster Resources DeputyMinister Ontario South Nation R iver ConservationAuthority eoMNR-OGS 1983 tssN0704-2752 Printedin Canada rsBN0-7743-8219-8 Publicationsof the Ontario Ministry of NaturalResources are available from the following sourcesOrders for publications should be accompanied by chequeor money order pay- ableto lhe Treasurerof Ontailo. Reports,maps, and price lists (personal shopping or mail order): PublicService Centre, Ministry of NaturalResources Room1640, Whitney Block, Queen's Park Toronto,Ontario M7A 1W3 Reportsand accompanying maps (personal shopping): OntarioGovernment Bookstore MainFloor,880 Bay Street Toronto,Ontario Reportsand accompanying maps (mail order or telephone orders): PublicationsServices Section, Ministry of GovernmentServices SthFloor,880 Bay Street Toronto,Ontario M7A 1NB Telephone(local calls), 965-6015 Toll-freelong distance, 1-800-268-7540 Toll-freefrom AreaCode 807, 0-ZENITH-67200 Thispublication can also be obtained from: OntarioMinistry of NaturalResources ConcessionRoad Kemptville j ontarioKoG 1J0 I Telephone613 - 258-3413 l l Thisproject was funded by the South Nation River Conservatton Authority, the Federal De- partmentof RegionalEconomic Expansion, and the Ontario Ministry of NaturalResources. Everypossible ef{ort is madeto ensurethe accuracyof the informationcontained in thisre- port,but the Ministryof NaturalResources does notassume any liabilityfor errorsthat may occur.Source references are includedin the reportand usersmay wish to verifycritical in- formation. Partsof this publicationmay be quotedif creditis given.lt is recommendedthat reference to thisreport be madein the following form: Poschmann,A,S., Klassen, K.E,, Klugman, M.A , andGoodings, D. 1983:SlopeStability of the SouthNation River and Portionsof the OttawaRiver; Ontario GeologicalSurvey, Miscellaneous Paper 112,20p Accompaniedby Geotechnical SeriesMaps 2486 and 2487,scale 1 :50 000. CriticalReader: O.L White ScientificEditor: Guy Kendrick 1000-83-TwinOffset FOREWORD SLOPESTABILITY STUDY OF THE SOUTH NATION RIVER AND PORTIONS OF THE OTTAWA RIVER Thrsreport is the secondreport of its type to be publishedby the OntarioGeological Survey Preparedby the staffof the EasternRegion Otfice of the Ministryof NaturalRe- sources,the reportdraws attention to theexistence of potentiallyunstable slopes along the valleyof the SouthNation River and its severaltributary streams together with part of the OttawaRiver. The clay soilsforming these slopes owe theirorigin to materialdeposited in the watersof the ChamplainSea which covered the areaduring deglaciation about 13 000 yearsago. Theobjective of thisreport is notonly to alertthe generalpublic, planners, and the mu- nicipalitiesto the potentialhazards, but alsoto encouragedevelopers and landowners to arrangefor adequategeotechnical investigation of all landin the vicinityof riverbanks and slopeswell in advanceof anyconstruction or developmentthereon. EG Pye Director Ont a ri o Geo log ic al Survey lll CONTENTS Introductron 1 Originand Characteristicsof theChamplain Sea Clays z Historyof Deposition Characteristicsof theChamolain Sea Clavs 3 SlopeFailure a FieldProgram 6 Airphotos 6 SlopeMeasurement 6 Analysis 6 SlopeClassr{icatron 8 SlopeStab rtyClasslfications . I S-mmarrT 1n .tn Acknowedgrg^14 Appendx 1 .........11 Co.nputerP'ogram ''11 Appendix2 12 ComputedFactors of Safetyfor SrrrueverlSitcq .......12 Beterences ..19 TABLE ', Table1--Some values for'Effective Angle of InternalFriction 0' 'Effective ', 'Pore Cohesionc' and Pressureru'obtained from site-soecific studres in the Ottawa and SouthNation River area FIGURES Figure1-The ChamplainSea and locationol thestudy area . .. z Fioure2a--Sheet Slide 3 Figure2b-Simple RotationalFailure j Frgure3a-Retrogressive Rotational Failure + Figure3b-RetrogressiveFlowslide ........ 5 Frgure4-Eanhf low. 5 FigureS--Showing the relationshipsbetween the slope rnclinations, theslope heights, and the Factorsof Safetyas computedfor this study 7 Figure6-Failed and unJailed slopes related to height,inclination, and the Factorsof Safety1 0 and 1.5 8 GEOTECHNICALSERIES MAPS (backpocket) Map2486 (coloured)-Slope Stability Study of theSouth Nation Fiver and Portionsof theOttawa River, Northern Sheet, Southern Ontano, scale 1:50 000, Map 2487(coloured)--Slope Stability Study of the SouthNation River and Portionsof theOttawa River, Southern Sheet, Southern Ontario, scale 1 :50 000 Conversion Factorsfor Measurementsin Ontario GeologicalSurvey Publications lfthe reader wishes to convert imperial units to Sl(metric) units or Sl units to imperialunits thefollowing multipliers should be used: CONVERSION FROM SI TO IMPERIAL CONVERSION FROM IMPERIAL TO SI Sl Unit Multiplied by Gives lmperial Unit Multiplied by Gives LENGTH lmm 0.03937 Inches inch 25.4 mm 1cm 0.39370 Inches inch 2.54 cm 1m 3.28084 feet toot 0.304I m 1m 0,049709 7 charns charn 201168 m 1km 0,621371 miles(statute) mile(statute) 1.609344 km AREA 1 cm2 01550 squareinches squarernch 6.4516 cm2 1m2 10.7639 squarefeet squarefoot 0.092903 04 1n2 1 km2 0 38610 squaremiles squaremIe 2 5899BB km2 lna 2,471054 acres 0.404685 6 ha VOLUME 1 cm3 0,06102 cubicinches 1 cubicinch 16.387064 cm3 1m3 35,3147 cubicfeet 1 cubicfoot 0,028316 85 ry13 1m3 1.3080 cubicyards 1 nrrhin rrard 0 764555 m3 CAPACITY 'I 1L 1 759755 pints prnt 0.568261 L 1L 0.879877 quarts. 1 nr 12rt 1j36522 ,1 I ^^il^^ L 0,219969 gailons I gdrur I 4.546090 MASS 1g 0.035273 96 ounces(avdp) ounce(avdp) 28 349523 S 1g 0.032150 75 ounces(troy) nr rnno /irntr\ 31.1034768 g 1kg 2.20462 pounds(avdp) pound(avdp) 0.45359237 kg 1 f(g 0.001102 3 tons(short) ton (short) 907.18474 kg 1t 1.1 02 31 1 tons(short) ton (short) 0.907184 74 t lKg 0.000984 21 tons(long) ton (long) 1016.0469088 kg '1 t 0.984206 5 tons(long) ton (long) 1.0160469088 t CONCENTRATION 1 g/t 0,029166 6 ounce(troy)/ 1 ounce(troy)/ 34.2857142 g/l ton(short) ton(short) 1 ^lt 0.583333 33 pennyweights/ 1 pennyweight/ 1,7142857 g^ ton(short) ton(short) OTHERUSEFUL CONVERSION FACTORS 1 ounce (troy)/ton(short) 20.0 pennyweights/ton(short) 1 pennyweighVton(short) 0.05 ounce(troy)/ton (short) NOTE-Conversionfactors which are in bold type are exact,The conversionfactors have beentaken fromor havebeen derived from factors given in the MetricPractice Guide for the Canadian Miningand MetallurgicalIndustries published by The MiningAssociation of Canadain coop- erationwith the CoalAssociation of Canada. vl SlopeStability Study of the South Nation River and Portionsof the Ottawa River by A.S.Poschmannl, K.E. Klassenz, M.A.Klugman3, and D. Goodingsa measuredesigned. These measures should be based INTRODUCTION upon the geotechnicalinvestigations carried out priorto any developmentof a site,Property damage and incon- veniencecan then be reduced. The SouthNatlon River and the OttawaRiver are two of the largestnvers in southernOntario. The SouthNation It must be stressedthat this classilicationof the Riverdrains an areaof about3700 km2. The Ottawa River slopesis presentedas a guideline,and not as a site drainsan areaof about145000 km2, The SouthNation specilicvalue for engineering design. Riverdescends 84 m overa distanceof 177km fromits The methodsused rn this reportare a refinementof 'Slope sourceto its lunctionwith the OttawaRiver (Chapman thosedeveloped in the report StabilityStudy of the and Putnam1966) Extensivedeposits of glaciallyde- RegionalMunicipality of Ottawa-Carleton'(Klugman and rivedmarine clays that were latd down in the Champlain Chung1976) to classifyslopes in thesepostglacial ma- Seaoccur in the study area. rineclays. The study involved locating and mappingdif- Thetendency for riverbanks and slopescomposed ferenttypes of failuresthat occur in slopesin the Cham- of ChamplainSea clays in southeasternOntario to fail plainSea clays. The slope heights and inclinationswere and cause argeand smallscale landslides, is causing measuredat pointson the slopesconsidered to be repre- sentativeof a sectionof slope,These survey data were an increasrngamount of interestand concern,Costly 'Factor damageto bu ldingsand lossof lifemay result from con- usedto calculatethe of Safety',which is a numeri- structionon unstableclay slopes. Because of theseprob- cal representationof the stabilityof a slope.These Fac- lems,the Ontario M nistryof NaturalResources ts endea- tors of Safetywere used n the processof classifyingthe slnnes Fach r:lass rdent f'pcl nffcrc' ntr dplincs fOf voring to c assrfythe c ay slopes accordingto their J'vvvJ. detef- ^+^hiri+\, ^^^^ ^.\/arp.j geotechnicainvestigation neces- >tdulllty ll I d Yd> u, ltg uuvElEu uyhri.hc tl lc vlCh:rnnlai" lq,, rplql Sea. mrningthe amountof san to erSur€ the safe use of a s te The classiiicaton of the slopesIn th s sensrtrveclay is intendedto alertdevelopers and plannersto the need The s opesexam ned n th s rspsl arecontained in for determinrngthe geotechnca evauat on oi thestabt - the So,.rt.Natror' Rrver watersned and alongthe Ottawa rtyof a slopeat a soecrftc