July 29, 2004

Douglas B. MacDonald
Washington State Department of Transportation
PO Box 47300
Olympia, WA 98504-7300

Re: I-90 Hyak to Easton Project

Dear Secretary MacDonald:

We urge the Washington State Department of Transportation (WSDOT) to provide for a high level of ecological connectivity in its plans to upgrade Interstate 90 east of Snoqualmie Pass.

There is a great need for correcting the problems created by the existing highway and increasing connectivity for wildlife and other organisms in this crucial area. At the same time, the central location of the interstate realignment and widening project near Snoqualmie Pass presents a unique opportunity for achieving this objective.

The solution should include the development of advanced measures, rather than historical methods such as substandard culverts. WSDOT has been recognized for its use of new technologies to reduce impacts to aquatic habitats, and we urge you to meet these same standards for the wide variety of species present in the I-90 project area.

The impacts of Interstate 90 include wildlife mortality due to roadkill, alteration of the physical and chemical environment, increased use of area by humans, and habitat fragmentation. The construction of the proposed project will also have impacts, such as the direct loss of habitat, disturbance and mortality from road construction, and potential release of sediment or toxic materials into the aquatic environment.

On a landscape scale, the I-90 corridor through Snoqualmie Pass is positioned between a number of important wilderness areas, national parks and other reserves, all of which provide refuge for wildlife. In recent years, substantial private and public land conservation efforts have helped protect and maintain the wildlife corridors between these areas in the Central Cascades. I-90 remains the single greatest barrier to movement of animals and genetic interchange between the north and south Cascades.

The potential effects of this project are magnified because the Hyak to Easton segment traverses the narrowest portion, east to west, in a continuous stretch of habitat from the Canadian border to northern California. From North Bend westward, and from Easton eastward, the once contiguous forest has now been lost to urban, suburban and agricultural development. The connections east of the crest are particularly important as little connection in the Douglas fir-grand fir and ponderosa pine forest types remain. Thus, the easternmost portion of the subject project takes on added significance. This requires a maximum effort be made in the Easton Hill/Kachess River segment.
Another key segment is where the freeway crosses several wetlands and creeks including Price Creek, Swamp Creek and Toll Creek. DOT not only needs to re-establish connections, but to restore the natural aquatic communities that were destroyed or damaged by the earlier highway constructions. The crossing at Gold Creek is another location that is particularly important, as the developments near the Pass have severely limited connections. This location, in conjunction with efforts to re-establish forest connections on other public lands in the vicinity, will be crucial to maintain this higher elevation corridor.

The species most vulnerable to habitat fragmentation are those with large home ranges and low population numbers, in particular carnivores (Haas 2000). The corridors of the Central Cascades have been shown to be used by wolverines (Gulo gulo), grizzly bears (Ursus arctos), and gray wolves (Canis lupus) (Fisher Consulting Services 2000), marten (Martes americana) and fisher (Martes pennanti). These are all listed or candidates for listing under the Endangered Species Act, and have also received conservation designations by the Washington State Department of Fish and Wildlife. We realize that the frequency of some of these carnivores south of I-90 is low, but we must consider the future growth of these populations as well. You are well aware of the impacts of vehicle collisions with elk (Cervus elaphus) and deer (Odocoileus hemionus). Similar impacts are occurring to medium sized carnivores, such as cougar (Puma concolor) and bobcat (Lynx rufus). More than 55 species of mammals currently or historically used the habitat in this vicinity and are affected by this stretch of the highway.

In addition to these large mammals, there are negative impacts on low mobility species such as reptiles and amphibians. Species that may be widespread today will eventually split into different populations if interbreeding is cut by I-90. More common today are the Western Redback (Plethodon vehiculum) and Pacific Giant Salamander (Dicamptodon tenebrosus) and the Cascades Frog (Rana cascadae); less common and already threatened species include the Larch Mountain Salamander (Plethodon larselli) and Tailed Frog (Ascapus truei). Fresh water mollusks are another major though little known group that is affected by the highway. The changes in climate that are evident today will only make this need for connectivity more acute.

Plants, especially nonvascular plants such as lichens, bryophytes and fungi, may also be affected by a wide concrete barrier.

It is important to provide a margin for error and lack of information. With a project that will last a half century or more, it would not be prudent to take the minimal approach to this problem, only to find later that a more complete solution is needed. The costs of retrofitting later are bound to far exceed the cost of providing the same level of connectivity during this major expansion.

It will be essential that the upcoming Environmental Impact Statement look at a full range of alternatives to carefully assess the relative merits of designs and costs of connectivity, habitat restoration and mitigation measures. This is not only required by the National Environmental Policy Act, but will provide the scientific community and broader public an opportunity to consider a full range of benefits to the biotic community. While some suggestions may seem hypothetical or too costly, that determination is premature before the Draft EIS stage. Scientific investigation has always benefited from reviewing ideas “out of the box.” The critical location and nature of this project demands that broad look, and an analysis of alternatives providing high levels of connectivity for all the affected species.

We appreciate the efforts of WSDOT to publish Discipline Reports for both aquatic and terrestrial species, and to bring together a Mitigation Development Team consisting of state and federal agency scientists to address these important issues. We understand from reviewing the Draft Mitigation Report that seven of the original fifteen Connectivity Restoration Areas have been noted as the highest priority sites, and that solutions are being considered for each of these sites to prevent or improve upon habitat fragmentation of species of concern. However, DOT should not assume that the others are of little importance. Each contributes in its own way, and deserves examination. One concern is that crossing structures at Coal Creek seem to have been prematurely eliminated from further consideration. The choices that WSDOT makes at each of these critical points will determine the success or failure of efforts to recover endangered and threatened species.

The practical study of the interrelationship of transportation and ecology is a growing field, and with this growth has come exemplary projects that will help inform the development of solutions for I-90. Transportation engineers and scientists have worked together in the United States to address wildlife connectivity issues in Florida, Arizona, Montana, and our own state of Washington. The unique opportunity presented by the I-90 Project provides a chance for us to build upon this knowledge to meet a new standard for transportation planning. Washington State could be a leader by using new and innovative designs to provide crossings for terrestrial vertebrates and invertebrates, both under and over highways, as well as exploring combinations of both terrestrial and aquatic crossings designed specifically to the conditions of the Central Cascades.

We appreciate your efforts to examine the wildlife connectivity issues. We look forward to the solutions that surface to provide high levels of wildlife passage in the interstate expansion and to a full range of alternatives in the Environmental Impact Statement.
We appreciate your efforts to examine the wildlife connectivity issues. We look forward to the solutions that surface to provide high levels of wildlife passage in the interstate expansion and to a full range of alternatives in the Environmental Impact Statement.

Sincerely,

Anthony P Clevenger, PhD
Research Scientist
Western Transportation Institute
Montana State University

Sandra Coveny
Conservation Biologist
Society for Conservation GIS
Corvallis, OR

Kristina A. Ernest, Ph.D.
Associate Professor
Department of Biological Sciences
Central Washington University

Demaris E. Garceau
Professor
Central Washington University

James R. Karr
Professor of Aquatic Sciences and Biology
University of Washington

John Marzluff
College of Forest Resources
Ecosystem Science and Conservation Division
University of Washington

John McLaughlin
Department of Environmental Sciences
Huxley College of the Environment
Western Washington University

Chris Morgan
Department of Environmental Sciences
Huxley College of the Environment
Western Washington University

Edward T. Nelson, Ph.D.
Professor and Undergraduate Coordinator
Biological Sciences Department
Southeastern Louisiana University

Dr. Dennis Paulson, Director
Slater Museum of Natural History
University of Puget Sound

* Institutional affiliations provided for information only; they do not imply institutional support.

Literature Cited

Fisher Consulting Services. 2000. The biological case for preserving lands in the I-90 corridor.

Haas, D. 2000. Distribution, relative abundance and roadway underpass responses of carnivores throughout the Puente-Chino Hills. M.S. Thesis. California State Polytechnic University, Pomona, California.

cc:
Senator Patty Murray, U.S. Congress
Senator Jim Horn, Chair, Washington State Senate Highways and Transportation Committee
Representative Ed Murray, Chair, Washington State House Transportation Committee
Aubrey Davis, Chair, Washington State Transportation Commission