Introduction
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Ice Age Floods Study of Alternatives Interpretation section j INTERPRETATION Introduction he Organic Act of 1916, which created the National Park Service, charged the TNPS with not only the task of preserving and protecting the parks’ resources, but also to “provide for the enjoyment of the same.” The “enjoyment” mandate has come to mean interpreting the meaning and value of the parks’ resources to the public. In most cases, interpretation can be provided on-site unless the area is too small or the resources too fragile. The larger the park or area and the larger the number of resources contained in that area, the more complex the interpretation becomes. The challenge within the Ice Age Floods 2. Developing physical and visual access Study Region is to creatively address to specific Floods resources. three major issues: 3. Developing an interpretive 1. Identifying Ice Age Floods resources, framework and program for the which are scattered across a four-state natural and cultural history of the area. These specifically include Floods region. resources related to Glacial Lake Columbia Basin Herald Missoula and to the flooding events associated with ice dam failure. M. Sear/ Tours arranged by the Ice Age Floods Institute bring the visitors face-to-face with the evidence of the Ice Age Floods. At Wilson Creek, the visitor can appreciate Bretz’s analysis and understand the Floods’ impact on the land. 83 F LO E OD G S A E C I Interpretation Area impacted by Glacial Lake Missoula and the Floods 84 Ice Age Floods Study of Alternatives Interpretation 1. Basic Concept he basic concept developed by the Study Team for interpreting the Floods story is Tthat the study area, which covers a four-state area, be defined as an Ice Ages Floods Geologic Region. Within the Floods Region would be Floods Pathways that follow existing highways. These Floods Pathways would provide visual and physical access to significant Floods features and help link the features as part of a coordinated project. There are a number of different media alternatives. The majority of approaches that can help a visitor existing Floods features are best understand and appreciate the many and experienced in person, either by walking varied aspects of the Ice Age Floods or driving to features, or by flying story. Because of the scale of the Floods overhead. Interpretation at specific region, a narrative approach may be the locations and regionwide could: most effective way to develop an • Explain the story of the Floods understanding of the larger story. This resources both at specific sites and at narrative could be in written format or regional and other interpretive be integrated with a number of multi- centers M. Sear/Columbia Basin Herald • Place a site into the context of the larger Floods story • Explain the geologic background of a site prior to the Floods • Interpret the cultural history of an area as influenced by the Floods, Tour groups mix with school groups tying in the dynamic historic story at Dry Falls Interpretive Center to with the geology of each area. see remarkable remnants of the Ice Age Floods. 85 F LO E OD G S A E C I Interpretation Floods2. Development of a Floods Tour Route Approach The Ice Age Floods Created Palouse Falls he original planning concept was to develop Floods Tour Routes and to direct Tvisitors to selected Floods features near major Interstates and U.S. Highways. Before the great floods, the Palouse River These routes would be defined as being “primary” or “secondary” based upon the type flowed down Washtucna Coulee to join of road and the number of significant Floods features nearby. After discussions with geologists and other Floods experts, it was agreed that this approach was overly the Columbia River in the Pasco Basin. simplistic and would not work as originally intended. With the number and variety of The huge torrents of the Floods filled Floods resources, it was felt that visitors would gain greater appreciation and understanding if a number of Floods Tour Routes were identified and marked, and overflowed Washtucna Coulee and allowing a greater variety of sites to visit. If time is limited, visitors could choose swept across the divide down into the conveniently located sites along their way. If they have several days, visitors could see a greater number of sites. adjacent Snake River Valley. This enormous overflow carved back the This modified planning concept defined as Pathways providing access to focused on identifying Floods Pathways significant Floods features. In many divide in one place enough to capture that would follow U.S. Highways as ways, this approach is more in keeping the Palouse River, diverting it south to well as state highways and local roads, with the paths taken by the original but would stay off interstate highways floods. the Snake. The lower 10 miles of the as much as possible. In some instances, Palouse now flow through a deep non-motorized trails and water trails It should be noted that the original could link to certain Floods features. concept was described as an interpretive spillway. Its last descent is over a 200- There would be no “hierarchy” of motor tour, but was rapidly expanded to foot cliff: Palouse Falls. routes based upon importance to the include auto, train, tour boat, airplane, Floods story; all would simply be bicycle and even hot air balloon tours. Facts 86 Ice Age Floods Study of Alternatives Interpretation Floods3. The Process of Determining the Most Effective Tour Route Hydraulic Dam etermining which existing roads and highways would be designated as What is a hydraulic dam? It is the D“Pathways” was based upon two criteria: (1) path of the original flood waters, and (2) the location of significant Floods features, including Glacial Lake Missoula. restriction of the rate of water flow caused by a narrowed reach in a river The Floods resulted from the release of Willamette Valley. The Floods continued water impounded in western Montana by down the lower Columbia to the ocean, valley. During a valley-filling flood, the ice dams near the mouth of the Clark which was 40 miles west of present-day narrows restrict flow, thus causing water Fork River. Glacial Lake Missoula Astoria, Oregon. It was important that extended far upstream from Missoula in Floods Pathways allow a visitor to follow upstream to pond partly and temporarily. several valleys. The lakeshore came the path of the floodwater from Missoula The most spectacular example of a within about 15 miles of the contental to the mouth of the Columbia at the divide. The volume of water from the Pacific Ocean. hydraulic dam during the Ice Age Floods Floods was so great that it followed was Wallula Gap, which restricted nearly several different channels across the The inventory of the Ice Age Floods Idaho Panhandle. When the floodwater resources was used to help determine 200 cubic miles of water in a huge, reached the relatively flat Columbia Basin pathways of the Floods. To date, more temporary pond in Pasco basin. On the of eastern Washington, it spread out than 350 Floods resources have been across three major drainage areas on its inventoried, and additional inventories are lower Columbia, a narrows near Kalama way to the Columbia River, Wallula Gap still being conducted. The four Study Zone also briefly ponded floodwater. This and the Columbia Gorge. At the Gorge, Working Groups, after identifying the the water was confined to the steep river resource sites, were asked to rank their narrows thus helped to back up valley. Farther down the Columbia River, Floods resource sites whenever possible, floodwater upstream, flooding not only a hydraulic dam was formed at the and those sites were located on a map of narrows at Kalama, Washington, and the the study area. The intent of the Pathways the Portland–Vancouver basin but also backwaters flooded south into the was to provide access to these sites. the Willamette Valley to beyond Eugene. Facts 87 F LO E OD G S A E C I Interpretation Floods Pathways, Loops, Spurs, and Gateway Communities 88 Ice Age Floods Study of Alternatives Interpretation Floods4. Recommended Routes of the Pathways Well-Traveled Meteorite Pathways An earlier discussion of the development of a tour route approach examined the The Willamette meteorite is the largest desirability of using the term “Pathways” over “Primary” and “Secondary” Floods ever found in the United States, weighing routes. The use of the generic term “Pathways” does not denote a hierarchy of routes, but is intended to indicate to visitors the various alternatives they can take to see 31,107 pounds. It was found in 1902 two Floods resources. These various alternatives include CONNECTING Pathways, LOOP miles northwest of West Linn, Oregon, at Pathways and SPUR pathways. Wherever appropriate, Floods Pathways should utilize existing designated state and National Scenic Byways. Public agencies should an elevation of 380 feet above sea level. coordinate with state transportation departments on these opportunities. These Apparently, an iceberg carried the recommended routes are intended to be conceptual in nature to illustrate the basic approach. More detailed management planning will be needed to determine specifically meteorite along with granite erratics the location of routes and interpretive facilities once the area is formally designated. from either the Cordilleran ice sheet or Gateway Communities to the perimeter of the Floods region, (5) the Purcell lobe in British Columbia to Related to the Pathways are “Gateway connectivity to existing roads, and (6) the Willamette Valley. The meteorite Communities,” which would be the ability to provide visitor services. entry points into the Ice Age Floods must have been moved with the glacial region and the network of Flood The Study Team identified the following iceflow to near Lake Pend Oreille and Pathways.