198:
140:
238:
158:
176:
33:
220:
171:
powerful current effects can be found, particularly on large-volume rivers. Scouting is advisable for inexperienced parties. Injuries while swimming are rare; self-rescue is usually easy but group assistance may be required to avoid long swims. Rapids that are at the lower or upper end of this difficulty range are designated Class III- or Class III+ respectively.
189:
maneuvers, scout rapids, or rest. Rapids may require "must make" moves above dangerous hazards. Scouting may be necessary the first time down. Risk of injury to swimmers is moderate to high, and water conditions may make self-rescue difficult. Group assistance for rescue is often essential but requires practiced skills. For kayakers, a strong
211:
exist may be small, turbulent, or difficult to reach. At the high end of the scale, several of these factors may be combined. Scouting is recommended but may be difficult. Swims are dangerous, and rescue is often difficult even for experts. Proper equipment, extensive experience, and practiced rescue skills are essential.
210:
Extremely long, obstructed, or very violent rapids which expose a paddler to added risk. Drops may contain large, unavoidable waves and holes or steep, congested chutes with complex, demanding routes. Rapids may continue for long distances between pools, demanding a high level of fitness. What eddies
188:
Intense, powerful but predictable rapids requiring precise boat handling in turbulent water. Depending on the character of the river, it may feature large, unavoidable waves and holes or constricted passages demanding fast maneuvers under pressure. A fast, reliable eddy turn may be needed to initiate
251:
Classifications can vary enormously, depending on the skill level and experience of the paddlers who rated the river. For example, at the 1999 International
Conference on Outdoor Recreation and Education, an author of a paddling guide pointed out that there is too much variation in what is covered
152:
Straightforward rapids with wide, clear channels which are evident without scouting. Occasional maneuvering may be required, but rocks and medium-sized waves are easily avoided by trained paddlers. Swimmers are seldom injured and group assistance, while helpful, is seldom needed. Rapids that are at
213:
Because of the large range of difficulty that exists beyond Class IV, Class V is an open-ended, multiple-level scale designated by class 5.0, 5.1, 5.2, etc. Each of these levels is an order of magnitude more difficult than the last. That is, going from Class 5.0 to Class 5.1 is a similar order of
170:
Rapids with moderate, irregular waves which may be difficult to avoid and which can swamp an open canoe. Complex maneuvers in fast current and good boat control in tight passages or around ledges are often required; large waves or strainers may be present but are easily avoided. Strong eddies and
232:
Runs of this classification are rarely attempted and often exemplify the extremes of difficulty, unpredictability and danger. The consequences of errors are severe and rescue may be impossible. For teams of experts only, at favorable water levels, after close personal inspection and taking all
116:
While a river section may be given an overall grading, it may contain sections above that grade, often noted as features, or conversely, it may contain sections of lower graded water as well. Details of portages may be given if these pose specific challenges.
259:
The grade of a river or rapid is likely to change along with the level of the water. High water usually makes rapids more difficult and dangerous, although some rapids may be easier at high flows because features are covered or washed out. At
108:
followed by a number. The scale is not linear, nor is it fixed. For instance, there can be difficult grade twos, easy grade threes, and so on. The grade of a river may (and usually does) change with the level of flow. Often a river or
252:
by the Class I designation, and proposed making further distinctions within the Class I flat water designations and Class I+ moving water designations, with the goal of providing better information for
268:
become easier to manage. Some rivers with high volumes of fast moving water may require little maneuvering, but will pose serious risk of injury or death in the event of a
264:, even rapids which are usually easy can contain lethal and unpredictable hazards. Conversely, some rapids may be easier with lower water levels when dangerous
485:
68:(ICF). The grade reflects the technical difficulty and skill level required associated with the section of river. The scale is of use to various
193:
is highly recommended. Rapids that are at the lower or upper end of this difficulty range are designated Class IV- or Class IV+ respectively.
64:
in the title. It should not be confused with the internationally used whitewater scale, which is published and adapted by a committee of the
305:
113:
will be given a numerical grade, and then a plus (+) or minus (-) to indicate if it is in the higher or lower end of the difficulty level.
375:
135:
and small waves. Few obstructions, all obvious and easily missed with little training. Risk to swimmers is slight; self-rescue is easy.
478:
349:
716:
327:
471:
233:
precautions. After a Class VI rapid has been run many times, its rating may be changed to an appropriate Class 5.x rating.
433:
416:
1710:
1241:
1731:
1705:
65:
1266:
17:
1407:
1357:
1251:
48:
is an
American system used to rate the difficulty of navigating a stretch of river, or a single (sometimes
1685:
1751:
911:
1695:
1647:
1530:
1680:
1397:
1362:
1204:
1746:
1690:
1382:
1147:
85:
1736:
1632:
1490:
1041:
926:
441:
197:
1470:
1317:
1279:
728:
667:
409:
Western whitewater: from the
Rockies to the Pacific, a river guide for raft, kayak, and canoe
382:
1700:
1422:
1246:
1006:
863:
813:
607:
281:
8:
1596:
1591:
1392:
1236:
858:
711:
632:
539:
353:
89:
81:
57:
120:
A summary of river classifications as presented by the
American Whitewater Association:
1622:
1535:
1500:
1352:
868:
773:
677:
569:
502:
1342:
1741:
1601:
1440:
1432:
1372:
1332:
1221:
1036:
798:
788:
574:
412:
37:
438:
Proceedings of the 1999 International
Conference on Outdoor Recreation and Education
1515:
1417:
1322:
1071:
921:
916:
893:
833:
662:
534:
1520:
1480:
1475:
1079:
966:
961:
745:
682:
652:
617:
612:
579:
544:
515:
1581:
1465:
1445:
1327:
1312:
1199:
1184:
1179:
1139:
1119:
1031:
873:
853:
818:
750:
735:
642:
564:
524:
463:
1725:
1662:
1657:
1642:
1627:
1576:
1571:
1337:
1302:
1256:
1216:
1211:
971:
843:
803:
549:
529:
265:
77:
1652:
1402:
1387:
1377:
1226:
1157:
1026:
991:
906:
848:
723:
622:
584:
559:
139:
69:
445:
237:
157:
1561:
1485:
1189:
1152:
1099:
823:
808:
783:
657:
261:
1667:
1347:
1231:
1171:
1129:
1001:
838:
706:
647:
637:
554:
190:
49:
1637:
1586:
1556:
1525:
1455:
1367:
1124:
1011:
996:
936:
883:
878:
778:
701:
691:
589:
175:
1307:
1274:
951:
793:
760:
1617:
1566:
1094:
1089:
1051:
956:
828:
765:
269:
153:
the upper end of this difficulty range are designated Class II+.
132:
73:
32:
1412:
1284:
1109:
1104:
1056:
1046:
1016:
941:
696:
627:
599:
498:
303:
256:, instructors leading trips, and families with young children.
110:
53:
406:
1510:
1495:
1450:
1194:
1167:
1114:
981:
976:
946:
931:
740:
510:
494:
253:
219:
1540:
1505:
1061:
1021:
986:
1460:
901:
434:"The Proposed Expanded Class I System of Rating Rivers"
214:
magnitude as increasing from Class IV to Class 5.0.
27:
Scale of skill needed to navigate a section of river
1723:
407:Cassady, Jim; Fryar Calhoun; Bill Cross (1994).
493:
60:to evaluate rivers throughout the world, hence
100:There are six categories, each referred to as
479:
381:. Deutscher Kanuverband. 1979. Archived from
486:
472:
304:Charlie Walbridge; Mark Singleton (2005).
299:
297:
328:"International Scale of River Difficulty"
246:
31:
1085:International scale of river difficulty
431:
352:. Deutscher Kanuverband. Archived from
294:
46:international scale of river difficulty
14:
1724:
467:
306:"Safety Code of American Whitewater"
24:
411:. Berkeley, CA: North Fork Press.
25:
1763:
95:
236:
218:
196:
174:
156:
138:
1242:Flooded grasslands and savannas
350:"whitewater scale organisation"
229:Extreme and Exploratory Rapids
58:American Whitewater Association
56:. The scale was created by the
425:
400:
368:
342:
320:
66:International Canoe Federation
13:
1:
287:
1408:Universal Soil Loss Equation
1358:Hydrological transport model
1252:Storm Water Management Model
122:
7:
275:
10:
1768:
912:Antecedent drainage stream
1676:
1648:River valley civilization
1610:
1549:
1531:Riparian-zone restoration
1431:
1293:
1265:
1166:
1138:
1070:
892:
759:
676:
598:
509:
1711:Countries without rivers
1686:Rivers by discharge rate
1398:Runoff model (reservoir)
1363:Infiltration (hydrology)
72:and activities, such as
1383:River Continuum Concept
1148:Agricultural wastewater
131:Fast moving water with
86:stand up paddle surfing
1706:River name etymologies
1633:Hydraulic civilization
1491:Floodplain restoration
1267:Point source pollution
1042:Sedimentary structures
442:Idaho State University
376:"whitewater scale DKV"
247:Caution in application
41:
1732:Canoeing and kayaking
1318:Discharge (hydrology)
1280:Industrial wastewater
761:Sedimentary processes
330:. American Whitewater
308:. American Whitewater
35:
1423:Volumetric flow rate
1007:Riffle-pool sequence
282:Degree of difficulty
1597:Whitewater kayaking
1592:Whitewater canoeing
1393:Runoff curve number
1237:Flood pulse concept
90:whitewater kayaking
82:whitewater canoeing
36:Class III rapid at
1623:Aquatic toxicology
1536:Stream restoration
1501:Infiltration basin
1353:Hydrological model
869:Sediment transport
692:Estavelle/Inversac
570:Subterranean river
42:
1752:Whitewater sports
1719:
1718:
1696:Whitewater rivers
1602:Whitewater slalom
1433:River engineering
1333:Groundwater model
1294:River measurement
1222:Flood forecasting
1037:Sedimentary basin
894:Fluvial landforms
799:Bed material load
575:River bifurcation
356:on April 20, 2016
244:
243:
38:Canolfan Tryweryn
16:(Redirected from
1759:
1681:Rivers by length
1516:River morphology
1418:Wetted perimeter
1323:Drainage density
834:Headward erosion
663:Perennial stream
535:Blackwater river
488:
481:
474:
465:
464:
458:
457:
455:
453:
448:on June 24, 2018
444:. Archived from
429:
423:
422:
404:
398:
397:
395:
393:
387:
380:
372:
366:
365:
363:
361:
346:
340:
339:
337:
335:
324:
318:
317:
315:
313:
301:
240:
222:
200:
178:
160:
142:
123:
21:
1767:
1766:
1762:
1761:
1760:
1758:
1757:
1756:
1722:
1721:
1720:
1715:
1691:Drainage basins
1672:
1606:
1545:
1521:Retention basin
1481:Erosion control
1476:Detention basin
1427:
1343:Hjulström curve
1295:
1289:
1261:
1205:Non-water flood
1162:
1134:
1080:Helicoidal flow
1066:
967:Fluvial terrace
962:Floating island
888:
763:
755:
746:Rhythmic spring
680:
672:
653:Stream gradient
594:
580:River ecosystem
545:Channel pattern
513:
505:
492:
462:
461:
451:
449:
430:
426:
419:
405:
401:
391:
389:
388:on May 28, 2016
385:
378:
374:
373:
369:
359:
357:
348:
347:
343:
333:
331:
326:
325:
321:
311:
309:
302:
295:
290:
278:
249:
228:
206:
184:
166:
148:
127:
98:
28:
23:
22:
15:
12:
11:
5:
1765:
1755:
1754:
1749:
1747:Rating systems
1744:
1739:
1734:
1717:
1716:
1714:
1713:
1708:
1703:
1698:
1693:
1688:
1683:
1677:
1674:
1673:
1671:
1670:
1665:
1660:
1655:
1650:
1645:
1640:
1635:
1630:
1625:
1620:
1614:
1612:
1608:
1607:
1605:
1604:
1599:
1594:
1589:
1584:
1582:Stone skipping
1579:
1574:
1569:
1564:
1559:
1553:
1551:
1547:
1546:
1544:
1543:
1538:
1533:
1528:
1523:
1518:
1513:
1508:
1503:
1498:
1493:
1488:
1483:
1478:
1473:
1468:
1466:Drop structure
1463:
1458:
1453:
1448:
1446:Balancing lake
1443:
1437:
1435:
1429:
1428:
1426:
1425:
1420:
1415:
1410:
1405:
1400:
1395:
1390:
1385:
1380:
1375:
1373:Playfair's law
1370:
1365:
1360:
1355:
1350:
1345:
1340:
1335:
1330:
1328:Exner equation
1325:
1320:
1315:
1313:Bradshaw model
1310:
1305:
1299:
1297:
1291:
1290:
1288:
1287:
1282:
1277:
1271:
1269:
1263:
1262:
1260:
1259:
1254:
1249:
1244:
1239:
1234:
1229:
1224:
1219:
1214:
1209:
1208:
1207:
1202:
1200:Urban flooding
1192:
1187:
1185:Crevasse splay
1182:
1180:100-year flood
1176:
1174:
1164:
1163:
1161:
1160:
1155:
1150:
1144:
1142:
1140:Surface runoff
1136:
1135:
1133:
1132:
1127:
1122:
1120:Stream capture
1117:
1112:
1107:
1102:
1097:
1092:
1087:
1082:
1076:
1074:
1068:
1067:
1065:
1064:
1059:
1054:
1049:
1044:
1039:
1034:
1032:Rock-cut basin
1029:
1024:
1019:
1014:
1009:
1004:
999:
994:
989:
984:
979:
974:
969:
964:
959:
954:
949:
944:
939:
934:
929:
924:
919:
914:
909:
904:
898:
896:
890:
889:
887:
886:
881:
876:
874:Suspended load
871:
866:
864:Secondary flow
861:
856:
854:Retrogradation
851:
846:
841:
836:
831:
826:
821:
819:Dissolved load
816:
811:
806:
801:
796:
791:
786:
781:
776:
770:
768:
757:
756:
754:
753:
751:Spring horizon
748:
743:
738:
736:Mineral spring
733:
732:
731:
721:
720:
719:
717:list in the US
714:
704:
699:
694:
688:
686:
674:
673:
671:
670:
665:
660:
655:
650:
645:
643:Stream channel
640:
635:
630:
625:
620:
615:
610:
604:
602:
596:
595:
593:
592:
587:
582:
577:
572:
567:
565:Drainage basin
562:
557:
552:
547:
542:
537:
532:
527:
525:Alluvial river
521:
519:
507:
506:
491:
490:
483:
476:
468:
460:
459:
424:
417:
399:
367:
341:
319:
292:
291:
289:
286:
285:
284:
277:
274:
248:
245:
242:
241:
234:
230:
224:
223:
216:
208:
202:
201:
194:
186:
180:
179:
172:
168:
162:
161:
154:
150:
144:
143:
136:
129:
97:
96:Classification
94:
26:
9:
6:
4:
3:
2:
1764:
1753:
1750:
1748:
1745:
1743:
1740:
1738:
1737:Hazard scales
1735:
1733:
1730:
1729:
1727:
1712:
1709:
1707:
1704:
1702:
1699:
1697:
1694:
1692:
1689:
1687:
1684:
1682:
1679:
1678:
1675:
1669:
1666:
1664:
1663:Surface water
1661:
1659:
1658:Sacred waters
1656:
1654:
1651:
1649:
1646:
1644:
1643:Riparian zone
1641:
1639:
1636:
1634:
1631:
1629:
1628:Body of water
1626:
1624:
1621:
1619:
1616:
1615:
1613:
1609:
1603:
1600:
1598:
1595:
1593:
1590:
1588:
1585:
1583:
1580:
1578:
1577:Riverboarding
1575:
1573:
1572:River surfing
1570:
1568:
1565:
1563:
1560:
1558:
1555:
1554:
1552:
1548:
1542:
1539:
1537:
1534:
1532:
1529:
1527:
1524:
1522:
1519:
1517:
1514:
1512:
1509:
1507:
1504:
1502:
1499:
1497:
1494:
1492:
1489:
1487:
1484:
1482:
1479:
1477:
1474:
1472:
1469:
1467:
1464:
1462:
1459:
1457:
1454:
1452:
1449:
1447:
1444:
1442:
1439:
1438:
1436:
1434:
1430:
1424:
1421:
1419:
1416:
1414:
1411:
1409:
1406:
1404:
1401:
1399:
1396:
1394:
1391:
1389:
1386:
1384:
1381:
1379:
1376:
1374:
1371:
1369:
1366:
1364:
1361:
1359:
1356:
1354:
1351:
1349:
1346:
1344:
1341:
1339:
1336:
1334:
1331:
1329:
1326:
1324:
1321:
1319:
1316:
1314:
1311:
1309:
1306:
1304:
1301:
1300:
1298:
1296:and modelling
1292:
1286:
1283:
1281:
1278:
1276:
1273:
1272:
1270:
1268:
1264:
1258:
1257:Return period
1255:
1253:
1250:
1248:
1245:
1243:
1240:
1238:
1235:
1233:
1230:
1228:
1225:
1223:
1220:
1218:
1217:Flood control
1215:
1213:
1212:Flood barrier
1210:
1206:
1203:
1201:
1198:
1197:
1196:
1193:
1191:
1188:
1186:
1183:
1181:
1178:
1177:
1175:
1173:
1169:
1165:
1159:
1156:
1154:
1151:
1149:
1146:
1145:
1143:
1141:
1137:
1131:
1128:
1126:
1123:
1121:
1118:
1116:
1113:
1111:
1108:
1106:
1103:
1101:
1098:
1096:
1093:
1091:
1088:
1086:
1083:
1081:
1078:
1077:
1075:
1073:
1069:
1063:
1060:
1058:
1055:
1053:
1050:
1048:
1045:
1043:
1040:
1038:
1035:
1033:
1030:
1028:
1025:
1023:
1020:
1018:
1015:
1013:
1010:
1008:
1005:
1003:
1000:
998:
995:
993:
990:
988:
985:
983:
980:
978:
975:
973:
970:
968:
965:
963:
960:
958:
955:
953:
950:
948:
945:
943:
940:
938:
935:
933:
930:
928:
925:
923:
920:
918:
915:
913:
910:
908:
905:
903:
900:
899:
897:
895:
891:
885:
882:
880:
877:
875:
872:
870:
867:
865:
862:
860:
857:
855:
852:
850:
847:
845:
844:Palaeochannel
842:
840:
837:
835:
832:
830:
827:
825:
822:
820:
817:
815:
812:
810:
807:
805:
804:Granular flow
802:
800:
797:
795:
792:
790:
787:
785:
782:
780:
777:
775:
772:
771:
769:
767:
762:
758:
752:
749:
747:
744:
742:
739:
737:
734:
730:
727:
726:
725:
722:
718:
715:
713:
710:
709:
708:
705:
703:
700:
698:
695:
693:
690:
689:
687:
684:
679:
675:
669:
666:
664:
661:
659:
656:
654:
651:
649:
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432:Ron Watters.
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418:9780961365042
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167:Intermediate
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78:riverboarding
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62:international
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18:Class I river
1701:Flash floods
1653:River cruise
1550:River sports
1403:Stream gauge
1388:Rouse number
1378:Relief ratio
1227:Flood-meadow
1158:Urban runoff
1084:
1072:Fluvial flow
1057:River valley
1027:River island
992:Meander scar
907:Alluvial fan
849:Progradation
724:Karst spring
668:Winterbourne
623:Chalk stream
585:River source
560:Distributary
452:September 1,
450:. Retrieved
446:the original
437:
427:
408:
402:
390:. Retrieved
383:the original
370:
358:. Retrieved
354:the original
344:
332:. Retrieved
322:
310:. Retrieved
258:
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212:
119:
115:
105:
101:
99:
70:water sports
61:
45:
43:
29:
1562:Fly fishing
1486:Fish ladder
1471:Daylighting
1190:Flash flood
1153:First flush
1100:Plunge pool
824:Downcutting
809:Debris flow
784:Aggradation
658:Stream pool
262:flood stage
1726:Categories
1668:Wild river
1348:Hydrograph
1338:Hack's law
1303:Baer's law
1247:Inundation
1232:Floodplain
1172:stormwater
1130:Whitewater
1002:Oxbow lake
839:Knickpoint
814:Deposition
707:Hot spring
648:Streamflow
638:Stream bed
555:Confluence
334:January 7,
312:January 7,
288:References
266:hydraulics
165:Class III:
50:whitewater
1638:Limnology
1587:Triathlon
1557:Canyoning
1526:Revetment
1456:Check dam
1368:Main stem
1125:Waterfall
1012:Point bar
997:Mouth bar
937:Billabong
884:Water gap
879:Wash load
859:Saltation
779:Anabranch
702:Holy well
590:Tributary
392:April 19,
360:April 19,
254:canoeists
227:Class VI:
185:Advanced
183:Class IV:
147:Class II:
1742:Paddling
1441:Aqueduct
1308:Baseflow
1275:Effluent
952:Cut bank
917:Avulsion
794:Bed load
774:Abrasion
276:See also
205:Class V:
126:Class I:
40:, Wales.
1618:Aquifer
1611:Related
1567:Rafting
1095:Meander
1090:Log jam
1052:Thalweg
957:Estuary
829:Erosion
766:erosion
678:Springs
633:Current
600:Streams
540:Channel
503:springs
499:streams
270:capsize
207:Expert
149:Novice
133:riffles
74:rafting
1413:WAFLEX
1285:Sewage
1168:Floods
1110:Riffle
1105:Rapids
1047:Strath
1017:Ravine
942:Canyon
697:Geyser
628:Coulee
613:Bourne
608:Arroyo
511:Rivers
495:Rivers
415:
260:spate/
88:, and
1511:Levee
1496:Flume
1451:Canal
1195:Flood
1115:Shoal
982:Gully
977:Gulch
947:Chine
932:Bayou
789:Armor
741:Ponor
516:lists
386:(PDF)
379:(PDF)
128:Easy
111:rapid
106:class
102:grade
54:rapid
1541:Weir
1506:Leat
1170:and
1062:Wadi
1022:Rill
987:Glen
972:Gill
922:Bank
764:and
729:list
712:list
683:list
618:Burn
501:and
454:2010
413:ISBN
394:2016
362:2016
336:2015
314:2015
191:roll
44:The
1461:Dam
927:Bar
902:Ait
104:or
1728::
497:,
440:.
436:.
296:^
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92:.
84:,
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52:)
685:)
681:(
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514:(
487:e
480:t
473:v
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364:.
338:.
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20:)
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