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s e c t i o n g

NATIONAL SIGNIFICANCE

1. National Significance

An examination of resources for their national significance is the first step in thestudy process. The Criteria for Parklands, a National Park Service publication, lists

the qualifications used for screening proposals for new park units to assure that onlythe most outstanding resources are added to the National Park System.

NPS applies ten specific standards todetermine national significance. The IceAge Floods study region meets four ofthese standards:

1. The Floods features are an outstandingexample of a particular type of resource.Identified sites within the Ice AgeFloods study area possessextraordinary features that exemplifycatastrophic floods of the Ice Age.

2. The Floods region possessesexceptional value or quality inillustrating or interpreting the natural orcultural themes of our nation’s heritage.Existing Floods resources offer anoutstanding opportunity to illustrate

and interpret an extraordinary naturalphenomenon.

3. The region offers superlativeopportunities for recreation, public useand enjoyment, and/or scientific study.The proposed Ice Age Floods regionties recreational and visitor use into acomprehensive and coordinatedinterpretive program across a four-state area. It also provides additionalopportunities for scientific study byidentifying significant Floods resourceareas.

4. Many features in the Floods regionretain a high degree of integrity as true,accurate, and relatively unspoiled

s u m m a r y

The Floods region is reviewed todetermine if it meets NPS requirements for

“national significance,” and if the resources withinthe area are threatened in any way. Level ofNational Significance is established in part byexamining NPS “service themes,” which look atboth natural and historic themes. Based uponthese criteria, the Floods region exceeds the basicrequirements for consideration.

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examples of the resource. Because of theimmense size and extent of the Floodsregion, many features remain thathave high degrees of integrity and arerelatively unspoiled.

The Criteria for Parklands also includesexamples of the types of characteristicsthat would help define an area or regionas being truly unique and worthy ofconsideration. Four resource evaluationsexamples listed apply directly to the IceAge Floods region:

• A landform or biotic area that hasalways been extremely uncommon inthe region or the nation.

• A site that possesses exceptional diversityor ecological components (species,communities, or habitats) or geologicalfeatures (landforms, observablemanifestations of geological processes).

• An area that has outstanding scenicqualities such as dramatic topographicfeatures, unusual contrasts in landforms

and vegetation, spectacular vistas, orother special landscape features.

• A site that is an invaluable ecologicalor geological benchmark due to anextensive and long-term record ofresearch and scientific discovery.

There are seven National NaturalLandmarks (NNLs) located within theIce Age Floods region. A NationalNatural Landmark is a nationallysignificant area that has been designatedby the Secretary of the Interior. To benationally significant, a site must be oneof the best examples of a type of bioticcommunity or geologic feature in itsphysiographic province. The Floods-related NNLs are:

• Wallula Gap, Washington—Glacialoutburst waters that crossed theChanneled Scablands during theSpokane floods were channeledthrough Wallula Gap. For severalweeks, as much as 200 cubic miles ofwater per day was delivered to a gap

Awesome signs of its passage

are still visible to this day.

Smithsonian Magazine, The Floods that

Carved the West, April 1995.

The floods carved out more than 50 cubic miles of

earth from western Montana to the Pacific Ocean.

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that could discharge less than 50 cubicmiles per day. Ponded water filled thePasco Basin and Yakima and Touchetvalleys to form temporary Lake Lewis.

• The Great Gravel Bar of Moses Coulee,Washington—This bar is perhaps thelargest example of bars created byoutburst floods on the ChanneledScabland. The bars are well-preservedand have only sparse vegetation.

• Drumheller Channels, Washington—The site is a spectacular tract of butte-and-basin scabland and providesexcellent geomorphic evidence for latePleistocene catastrophic floods on theColumbia Plateau.

• Grand Coulee, Washington—GrandCoulee is the largest coulee in theColumbia Plateau and is probably theworld’s finest example of a recessionalcataract gorge.

• Crown Point, Oregon—The CrownPoint section of the Columbia Gorge

illustrates more gradual stream valleyformation as downcutting kept pacewith the rise of the Cascade Range.The Columbia River Gorge at CrownPoint passes from the steeper, morerugged terrain of the western slopes ofthe Cascade Range to rollingcultivated plains. The promontoryprovides a strategic vantage point forobserving this classic illustration ofriverine process.

• Willamette Flood Plain, Oregon—Thesite represents the largest remainingnative and unplowed example ofbottomland interior valley grasslands inthe North Pacific Border natural region.

• Giant Flood Ripples, Montana—During is maximum stages, GlacialLake Missoula had a surface area of2,900 square miles and containedmore than 500 cubic miles of water.With the failure of the ice dam nearCabinet Gorge, the lake drained in justa few days, releasing catastrophicfloods of enormous magnitude across

the Columbia Plateau. Thiscatastrophic flood withdrawal wasrecognized by J. T. Pardee. Hedescribed various types of evidencesuch as scouring, high eddy depositsof flood debris, flood bars of bouldersand coarse gravel, and a succession ofgiant arcurate ripples or ridges ofgravel resting on bedrock surfaces.

The finest examples of these giantflood ripples are found 12 miles northof Perma, Montana. The giant ripplesappear as ridges 15 to 50 feet high,100 to 250 feet wide and from 100yards to a half mile long. Theygenerally traverse the direction of thecurrent. The form, structure, andarrangement of these features aresimilar to those of ordinary currentripple marks, but the features are solarge that the term “ripple mark”seems inappropriate. It is believed thatthe giant ripple marks could only havebeen formed by water at least 800 feetdeep, moving over Markle Pass atvelocities up to 55 miles per hour.

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The national significance of these sevenNNLs has already been established, andwith the addition of a multitude of otherFloods-related resources, combine tomake the Ice Age Floods region aspectacular assemblage of Floodsresources that exceed the requirementsfor recognition of a nationally significantresource.

ConclusionBased upon the requirementsestablished in the NPS Criteria forParklands, the Ice Age Floods regionexceeds the basic requirements forconsideration under the criteria fornational significance. These Floods arethe greatest scientifically documentedfloods known to have occurred inNorth America and are one of threedocumented geologic areas in the worldthat experienced catastrophic Ice Agefloods of a similar magnitude. Inaddition, NASA intensely studied theChanneled Scablands for comparisonsto similar catastrophic flooding thatscientists believe occurred on the planetMars.

F l o o d s

Highest Velocity of the Flood Waters

Along the entire flood route between

Glacial Lake Missoula and the Pacific

Ocean, the great floods spread out over

wide areas and then funneled through

constrictions. The narrowest constriction

of all was near Crown Point in the

Columbia River Gorge, where all 500

cubic miles of water were forced between

tall cliffs only 1.5 miles apart. Like a jet

of water exiting a nozzle, the flow

accelerated from the narrow opening,

probably reaching speeds of 80 miles an

hour before slowing and spreading out

over the Portland Basin.

F a c t s

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2. Integrity

The term “integrity” has two definitions, both of which are closely related. The firstrefers to a state or quality of being complete, and the second addresses the quality

of being unimpaired or unmarred. One interesting feature of the Ice Age Floodsresources is the fact that many Flood resources are still visible and have not beendamaged by human development or natural processes over more than 13,000 years.The existing Floods resources captured the interest of Pardee and Bretz, who were ableto develop their theories from the things that they could see. The huge scale of the IceAge Floods region helps in preserving the integrity of the resource; most changes seemminor when considering the enormity of the region and the sheer size of individualfeatures. The immensity of the ripple marks in Camas Prairie, Montana, the width ofDry Falls, and depth of the plunge pools, and 800-foot flood strandlines that are stillvisible all contribute to exceptional integrity of the Ice Age Floods resources. Anumber of Floods resources are virtually untouched, and many are so resistant tochange that even large-scale mining operations have not had much impact.

The fact that several Floods features arewithin protective management on publiclands helps ensure the integrity of theresources. Some private landowners alsoprotect Flood features on their propertythrough voluntary stewardship. Some ofthese features are designated as NationalNatural Landmark sites.

Driving through the landscape, a motoristfamiliar with the story of the Floods andwith a knowledge of specific types of

Floods features can’t help but notice theevidence left behind. This evidence ismuch the same as it was when Bretz andPardee made their discoveries.

ConclusionThe Ice Age Floods resources, themajority of which have been largelyunchanged for thousands of years,possess a very high degree of “integrity”and meet the requirements of PL 105-391.

Palouse Falls State Park, Washington

Moses Coulee gravel bar, Douglas County,

Washington

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