Cascadia Winter 2005
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News and information from the Oregon Department of Geology & Mineral Industries Volume 4, Number 1 www.OregonGeology.com Winter 2005 Where will it be tomorrow? In this issue: From your State Geologist – page 2 Our changing Oregon coast Please don’t take the cobbles – page 3 Tsunami hazard mitigation update – page 4 owhere is nature’s ability to shape the New coastal staff – page 5 Nlandscape more Measuring beach morphodynamics – page 6 apparent than on the ocean Shoreline change in littoral cells – page 8 shore. The ocean, aided by tides, rain, rivers, and cur- South Oregon coast mapping – page 10 rents, constantly and some- Know, know NANOOS – page 10 times dramatically chops away at the land. The result of this natural process af- fects those who have chosen Who owns the beach? to live within this dynamic Most people think Oregon’s beaches landscape. Our coastal are publicly owned. Th at’s not entirely communities are growing correct. Th e public does own the wet sand faster than ever before, but beach, up to the ordinary high tide line. the price for some is homes But the dry sand beach is usually part of abandoned and communi- the adjoining upland property. In many ties threatened by the same cases, this is privately owned. forces that drew people Even so, the public has a perpetual there. Our coast is also seis- easement to use the dry sand beach up mically active and subject to the statutory vegetation line or the line to infrequent but severe cat- of established upland shore vegetation, astrophic earthquakes and whichever is more inland. Th is easement tsunamis that have flood- is set out in the Oregon’s Beach Bill. Th e ed low-lying shores, bays, Beach Bill guarantees the public unre- and river valleys. Televi- stricted use of dry sand beaches, even sion images of landslides those that are privately owned. and tsunamis also remind Many state agencies share responsi- us how sudden and cata- bility for managing resources and uses in strophic these forces can be. Oregon’s coastline, which extends three Inside this issue of Cas- nautical miles (5.6 kilometers) from shore. cadia, you’ll learn how Many of these responsibilities are now scientists at the Oregon guided by the policies of the Territorial Department of Geology Sea Plan. Even so, the task of coordinating and Mineral Industries policies and agencies is complicated. are addressing the com- The dynamic nature of Oregon’s coastline is evident even As demand for coastal development plex and sometimes costly along the same stretch of beach. Here in the Neskowin increases, the geologic information the questions of understanding littoral cell, wave-caused erosion has stripped the beach Department of Geology and Mineral In- and dunes of sand, threatening homes, while new dunes dustries (DOGAMI) provides serves as coastal processes and the advance on other dwellings. You can learn more about lit- interaction between nature toral cells on page 8. (Photos: Jonathan Allan) a basis for prudent decision-making in and man. resource development and land manage- (continued on page 5) 1 www.OregonGeology.com from the Oregon Department of Geology and Mineral Industries making. Developing a means to distribute Notes from your information and data is as important as collecting and compiling it. Our coastal staff regularly meets with coastal govern- State Geologist ment and planners to explain coastal pro- by Vicki S. McConnell cesses. Th ey have organized several work- Oregon State Geologist shops to address tsunami evacuation and coastal processes. We now have a Coastal Processes and Hazards Working Group that meets to exchange information about n 1999 the 71st Legislative Assembly of benefi ts for forming partnerships with activities and identify problems that could Oregon acknowledged the increased coastal communities and organizations use a coordinated response eff ort. Ipressure on Oregon’s coastlines and responsible for the health and welfare In fi ve years we have forged strong authorized DOGAMI to open a Coastal of the coast. After considering several working relationships with many coastal Field Offi ce. Th e last time a fi eld offi ce excellent proposals for co-locating, we communities to assist with hazard miti- for DOGAMI’s Geologic and Services were delighted to accept the off er of the gation and education about coastal pro- Program had been opened was in 1937 Oregon Coastal Zone Management As- cesses and response, and we have built when the agency was formed! Th is action sociation (OCZMA) to co-locate in their a reputation as a “go-to” scientifi c team. by the legislature speaks volumes about Newport, Oregon offi ce. Th e offi ce is We are coordinators with federal, state, the interest and concern that Oregon has modest and not staff ed for visitor infor- and academic organizations to collect and for its coastlines, beaches, headlands, and mation, but you can learn more about distribute basic information about coastal littoral cells. In early 2000 we announced it and the staff by visiting our website: processes ranging from wave energy to at a DOGAMI Governing Board meeting www.OregonGeology.com. beach cobble migration (see page 6, Coast- the opening of the Coastal Field Offi ce in al Observatory story). Finally, we continue Newport, Oregon with our permanent to listen to what the coastal communities staff consisting of a Regional Geologist Ultimately, our mission tell us they need. Th is year we have includ- and a Coastal Geomorphologist. is to assist coastal ed a proposal in our mapping program to We had several goals in mind for the communities with land- initiate a geologic mapping project along new fi eld offi ce and its professional staff . the south coast in response to increases in Now after fi ve years we can evaluate our use decisions by helping population and development pressures on performance and review our strategic communities understand city and county governments. plan. We have increased our knowledge What do the next fi ve years hold? We of the processes that shape our coast and the processes and want to complete all the tsunami inun- about how coastal communities view hazards that shape our dation mapping for coastal communities their relationship with those processes. coastline. and begin to develop maps for the less Ultimately, our mission is to assist coastal populated areas that host large visitor communities with land-use decisions populations. Our work would include new by helping communities understand the We recognize that coastal communi- information acquired from study of the processes and hazards that shape our ties face a variety of hazards; some, such as Sumatra earthquake and tsunami of 2004. coastline. Coastal communities are not the tsunami hazard, are unique to coastal We want to expand our beach morpho- restricted to cities and counties but also areas. A primary scientifi c goal for the dynamic monitoring to include most of state and federal agencies that have re- Coastal Field Offi ce staff has been charac- the northern coast and incorporate sand sponsibilities to coastal residents and to terizing and mitigating for coastal hazards. budget data. We plan to incorporate our stewarding the Oregon coast. See page 5 Read up on some of our projects about tsu- dynamic revetment data into research for of this Cascadia for a list of some of the namis on page 4. We also recognize that developing improved shoreline protection most involved state agencies. the very processes that shape our coast- structures. We want to make all our data Our fi rst goal was to fi nd a location line are not well understood and we lack and maps available and interactive from for the fi eld offi ce that would be as acces- basic data to increase our understanding. our website. sible as possible to coastal communities. Feature stories throughout this Cascadia It gives me great pleasure to announce As the coastline of Oregon is about 360 publication explain some of our projects we have had a banner fi rst fi ve years for miles (580 km) long there is no simple to monitor and collect data that our part- the Coastal Field Offi ce and we plan to centralized location. We did, however, ners, policy makers, and scientists alike continue with enthusiasm, genuine inter- want to capitalize on a location with can use for scientifi c and policy decision- est, and strong science. 2 www.OregonGeology.com from the Oregon Department of Geology and Mineral Industries Cape Lookout shoreline stabilization study G E O L O G Y F A N O D T N M I E N M E T R R A A L Please don’t take the cobbles P I E N D D by Jonathan Allan U N S O T G R E I R E S ignificant erosion along the Oregon O coast during recent winters is the Sresult of an unprecedented number 1937 of major storms that generated excep- Cascadia is published by the Oregon tionally high waves, together with the un- Department of Geology usual impacts of the 1982-83 and 1997-98 and Mineral Industries 800 NE Oregon Street, #28, El Niños. The erosion has been especially Suite 965, Portland, OR 97232 severe at Cape Lookout State Park on the (971) 673-1555 FAX (971) 673-1562 northern Oregon coast. Cape Lookout State Park is located at Governing Board the south end of a “pocket beach” litto- William Elliott, Chair - Lake Oswego ral cell, centered about 1.25 miles (2 km) (image courtesy of Don Haagensen - Portland north of Cape Lookout and at the south Dr. Paul Komar, Vera E.