Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “Coastal Engineering”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources

Coastal effects

The Coasts chapter of the Third National Climate Assessment, published in 2014, focused on coastal lifelines at risk, economic disruption, uneven social vulnerability, and vulnerable ecosystems. This Coastal Effects chapter of the Fourth National Climate Assessment updates those themes, with a focus on integrating the socioeconomic and environmental impacts and consequences of a changing climate. Specifically, the chapter builds on the threat of rising sea levels exacerbating tidal and storm surge flooding, the state of coastal ecosystems, and the treatment of social vulnerability by introducing the implications for social equity. U.S. coasts are dynamic environments and economically vibrant places to live and work. As of 2013, coastal shoreline counties were home to 133.2 million people, or 42% of the population. The coasts are economic engines that support jobs in defense, fishing, transportation, and tourism industries; contribute substantially to the U.S. gross domestic product; and serve as hubs of commerce, with seaports connecting the country with global trading partners. Coasts are home to diverse ecosystems such as beaches, intertidal zones, reefs, seagrasses, salt marshes, estuaries, and deltas that support a range of important services including fisheries, recreation, and coastal storm protection. U.S. coasts span three oceans, as well as the Gulf of Mexico, the Great Lakes, and Pacific and Caribbean islands. The social, economic, and environmental systems along the coasts are being affected by climate change. Threats from sea level rise (SLR) are exacerbated by dynamic processes such as high tide and storm surge flooding (Ch. 19: Southeast, KM 2) , erosion (Ch. 26: Alaska, KM 2) , waves and their effects, saltwater intrusion into coastal aquifers and elevated groundwater tables (Ch. 27: Hawaiʻi & Pacific Islands, KM 1; Ch. 3: Water, KM 1) , local rainfall (Ch. 3: Water, KM 1) , river runoff (Ch. 3: Water, KM 1) , increasing water and surface air temperatures (Ch. 9: Oceans, KM 3) , and ocean acidification (see Ch. 2: Climate, KM 3 and Ch. 9: Oceans, KM 1, 2, and 3 for more information on ocean acidification, hypoxia, and ocean warming) . Although storms, floods, and erosion have always been hazards, in combination with rising sea levels they now threaten approximately $1 trillion in national wealth held in coastal real estate and the continued viability of coastal communities that depend on coastal water, land, and other resources for economic health and cultural integrity (Ch. 15: Tribes, KM 1 and 2) .

Report↗

The shallow stratigraphy and sand resources offshore of the Mississippi Barrier Islands

Coastal Mississippi is protected by a series of barrier islands ranging in length from 10-25 kilometers that are less than 2 kilometers wide. The majority of these islands comprise the Gulf Islands National Seashore (GUIS), an ecologically diverse shoreline that provides habitat for wildlife including migratory birds and endangered animals. The majority of GUIS is submerged, and aquatic environments include dynamic tidal inlets, ebb-tide deltas, and seagrass beds. The islands are in a state of decline, with land areas severely reduced during the past century by storms, sea-level rise, and human alteration. Morton (2008) estimates that since the mid-1800s up to 64 percent of island surface area has been lost. Heavy damage was inflicted in 2005 by Hurricane Katrina, which passed by as a Category 3 storm and battered the islands with winds of more than 160 kilometers per hour and a storm surge up to 9 meters. Since 2007, the U.S. Geological Survey (USGS), in collaboration with the National Park Service, has been mapping the seafloor and substrate around the islands as part of the USGS Northern Gulf of Mexico Ecosystem Change and Hazard Susceptibility project. The purpose of these investigations is to characterize the near-surface stratigraphy and identify the influence it may have on island evolution and fate. In 2009, this effort provided the basis for a collaborative effort with the U.S. Army Corps of Engineers (USACE) to expand the investigation outside of GUIS boundaries as part of the Mississippi Coastal Improvement Project (MsCIP). The MsCIP program consists of structural, nonstructural, and environmental project elements to restore portions of coastal Mississippi and GUIS affected by storm impact. The project includes the placement of sand along the islands, both on the present beaches and within the littoral zone, to mitigate shoreline erosion and breaching. This action requires the location and assessment of offshore sand or sediment deposits that can provide suitable material for shoreline renourishment. The geophysical and sample information collected by the USGS during geologic investigations provides this information. As part of the MsCIP program, in March 2010 the USGS mapped approximately 300 square kilometers of seafloor around GUIS. Interferometric swath bathymetry, sidescan sonar, and Chirp sub-bottom profiling were used to characterize seafloor elevations, texture, and the underlying stratigraphy. On the basis of this information, potential sediment resources were identified. The most promising offshore deposits for beach restoration include shoals, lowstand valley fill, tidal delta deposits, abandoned barrier deposits, and dredge spoil. Of these, lowstand valley fill deposits and dredge spoil are less desirable; lowstand deposits are buried under a 2- to 4-meter blanket of mud, and dredge spoil volume is small. A relict tidal delta and submerged shoals are the most desirable deposits; the tidal delta contains a large volume of material still exposed on the seafloor, and parts of submerged shoals have modest volume and thin mud cover.

Mississippi↗

Coastal Louisiana ecosystem assessment and restoration program: The role of ecosystem forecasting in evaluating restoration planning in the Mississippi River Deltaic Plain

The development of ecosystem management plans to restore and rehabilitate natural resources requires an understanding of how specific ecological mechanisms regulate the structure and function of ecosystems. To achieve restoration goals, comprehensive plans and engineering designs must effectively change environmental drivers at the regional level to reduce stress conditions at the local environment that are responsible for ecosystem degradation. This document focuses on the Coastal Louisiana Ecosystem Assessment and Restoration (CLEAR) ecosystem forecasting framework and how it can be used to support the analysis of Louisiana’s coastal restoration plans. Specifically, the framework is designed to (1) develop and incorporate conceptual ecological models that can be used to integrate ecological needs and opportunities with engineering designs, (2) utilize wetland loss rates to describe the most likely “future without” scenario for a variety of ecosystem attributes, (3) estimate broad ecosystem responses to restoration alternatives based on processes associated with succession of geomorphic and ecological systems, and (4) calculate ecological benefits for incorporation into decision support tools associated with large-scale geomorphic and hydrologic processes. This paper provides a brief overview of the spatial framework and modular design of the CLEAR ecosystem forecasting framework and describes in greater detail the evolution of the landscape change module, concepts for its refinement, and how it was utilized in evaluating a coastal restoration alternative proposed in the Coastal Protection and Restoration Authority Preliminary Draft Master Plan. Such projections by the CLEAR forecasting framework can evaluate processes and conditions that result in sustainable coastal ecosystems with habitat functions that support higher trophic levels.

Louisiana↗

Hydrology and tree-distribution patterns of karst wetlands at Arnold Engineering Development Center, Tennessee

Flooding regimes, ground-water interactions, and tree distribution patterns were determined in seasonally flooded sinkhole wetlands at Arnold Engineering Development Center near Manchester, Tennessee. The wetlands are ecologically significant because they support coastal-plain plants and animals far from their typical ranges. S urface-water stage, ground-water levels, rainfall, and streamflow were monitored at or near five wetland sites. Sinking Pond, Willow Oak Swamp, and Westall Swamp are compound sinks with depths greater than 2.5 meters, visible internal drains, and complex bottom topography dominated by coalesced sinkholes and connecting channels. Tupelo Swamp and Goose Pond are karst pans with depths less than 1.5 meters, flat bottoms, and without visible internal drains. Stage rose and fell abruptly in the compound sinks. Maximum water depths ranged from 2.6 meters in Westall Swamp to 3.5 meters in Sinking Pond. Water levels in wells adjacent to Sinking Pond and Westall Swamp rose and fell abruptly, corresponding closely to surface-water stage throughout periods of high water. The two karst pans filled and drained more gradually, but remained flooded longer than the compound sinks. The maximum recorded water depths were 1.1 meters in Tupelo Swamp and 0.7 meter in Goose Pond. Water levels in nearby wells remained lower than the stage in the pans throughout the study period. Tree species were identified and the elevations and diameters of individual trees were measured along 10 transects. Two transects crossed Sinking Pond, two crossed Tupelo Swamp, and one crossed Willow Oak Swamp. The remaining five transects crossed intermittent drainageways that carry flow into or out of Sinking Pond. Transects through ponds had fewer trees but more basal area per unit area of land surface than did transects through channels. Water tupelo (Nyssa aquatica L.) dominated the interior of Tupelo Swamp and had minimal overlap in terms of elevation and flooding duration with other wetland trees that were confined to the pond's periphery. Overcup oak (Quercus lyrata Walt.) dominated the interior of Sinking Pond. Overlap between overcup oak and other wetland trees in terms of elevation and flooding frequency was minimal across the deeper Sinking Pond transect but was substantial across the shallow transect. Willow oak (Quercus phellos L.) dominated the interior of Willow Oak Swamp and had a relation to other wetland trees similar to that of overcup oak in the shallow Sinking Pond transect. Transects across broad swales had a relatively large degree of vertical zonation among wetland and upland tree species. Along transects through well defined channels, elevation distributions of wetland and some upland tree species were grouped near each other and near the distribution of land-surface elevations.

Tennessee↗

Evaluation of the U.S. Geological Survey standard elevation products in a two-dimensional hydraulic modeling application for a low relief coastal floodplain

Growing use of two-dimensional (2-D) hydraulic models has created a need for high resolution data to support flood volume estimates, floodplain specific engineering data, and accurate flood inundation scenarios. Elevation data are a critical input to these models that guide the flood-wave across the landscape allowing the computation of valuable engineering specific data that provides a better understanding of flooding impacts on structures, debris movement, bed scour, and direction. High resolution elevation data are becoming publicly available that can benefit the 2-D flood modeling community. Comparison of these newly available data with legacy data suggests that better modeling outcomes are achieved by using 3D Elevation Program (3DEP) lidar point data and the derived 1 m Digital Elevation Model (DEM) product relative to the legacy 3 m, 10 m, or 30 m products currently available in the U.S. Geological Survey (USGS) National Elevation Dataset. Within the low topographic relief of a coastal floodplain, the newer 3DEP data better resolved elevations within the forested and swampy areas achieving simulations that compared well with a historic flooding event. Results show that the 1 m DEM derived from 3DEP lidar source provides a more conservative estimate of specific energy, static pressure, and impact pressure for grid elements at maximum flow relative to the legacy DEM data. Better flood simulations are critically important in coastal floodplains where climate change driven storm frequency and sea level rise will contribute to more frequent flooding events.

North Carolina↗

Advancing best practices for the analysis of the vulnerability of military installations in the Pacific Basin to coastal flooding under a changing climate – RC-2644

Coastal flooding takes many forms, ranging from major flooding associated with storms to minor flooding associated with exceptionally high tides and other oceanic and atmospheric phenomena on storm-free days. A major societal challenge is to understand and predict how flood magnitude and frequency will manifest at particular places and times, now and in the future. Of particular interest here is how coastal flooding will impact Department of Defense (DoD) installations. In response to this need, this work aims to advance the practical application of statistical and other analytical techniques that can be used to assess the exposure, and ultimately the vulnerability, of built and natural environments to the impacts of coastal flooding. A variety of methods are described and applied to assess exposure. This includes tide gauge station-based diagnosis and prognosis of patterns and trends of Still Water Level, techniques to characterize the expression of ‘lesser extremes’ (e.g., sub-annual to subdecadal event probabilities), and region-wide analysis that improves upon results obtained from conventional single-tide gauge analyses. A novel hybrid statistical and dynamical modeling approach is applied to the analysis of Total Water Levels, necessary for exposure assessment along shorelines exposed to wave action. The hybrid exposure assessment modeling approach is incorporated into a broader mission-based protocol for the assessment of resilience to coastal flooding at the installation level. Demonstrated via an exemplar assessment, which takes into account functional (lost day) as well as financial impacts (lost dollars), the protocol meets the demand for an actionable characterization of how DoD installations will be affected by coastal flooding and improves DoD’s ability to make informed decisions about how to adapt to its effects. The methods described, evaluated, and applied here, including innovative approaches and proof-of-concept products developed through this work, are incorporated into and considered within an analytical framework that serves as guidance as to their relative merits with respect to coastal flood exposure assessment in various circumstances and settings, and illustrates best practices. This will provide engineers, scientists and other practitioners with an enhanced capability to generate information that can be used to support area-wide assessment related to climate adaptation planning and disaster risk reduction as well as site-specific analysis related to design and maintenance of facilities and infrastructure. While the focus is on a select set of DoD sites in the Pacific Basin, the results have broad applicability nationally as well as globally.

Final Report↗

Selected aquifer-test information for the coastal plain aquifers of South Carolina

Aquifer and well hydraulic characteristics were determined from more than 100 multiple-well and single-well aquifer tests in the Coastal Plain of South Carolina and tabulated by county. Multiple-well aquifer tests were analyzed by the This method for nonleaky aquifers and the Hantush-Jacob method for leaky aquifers. Single-well tests were analyzed by straight line solution techniques for drawdown and recovery tests. Specific-capacity data are presented for many areas where aquifer-test information is sparse. The characteristics determined are based largely on well performance tests conducted by well drillers and consulting engineers. Although use of this information has many limitations, it has value in establishing transmissivity and storage coefficient values for the Coastal Plain aquifers. (Peters-PTT)

South Carolina↗

Modeled future peak streamflows in four coastal Maine rivers

To safely and economically design bridges and culverts, it is necessary to compute the magnitude of peak streamflows that have specified annual exceedance probabilities (AEPs). Annual precipitation and air temperature in the northeastern United States are, in general, projected to increase during the 21st century. It is therefore important for engineers and resource managers to understand how peak flows may change in the future. This report, prepared in cooperation with the Maine Department of Transportation (MaineDOT), presents modeled changes in peak flows at four basins in coastal Maine on the basis of projected changes in air temperature and precipitation. To estimate future peak streamflows at the four basins in this study, historical values for climate (temperature and precipitation) in the basins were adjusted by different amounts and input to a hydrologic model of each study basin. To encompass the projected changes in climate in coastal Maine by the end of the 21st century, air temperatures were adjusted by four different amounts, from -3.6 degrees Fahrenheit (ºF) (-2 degrees Celsius (ºC)) to +10.8 ºF (+6 ºC) of observed temperatures. Precipitation was adjusted by three different percentage values from -15 percent to +30 percent of observed precipitation. The resulting 20 combinations of temperature and precipitation changes (includes the no-change scenarios) were input to Precipitation-Runoff Modeling System (PRMS) watershed models, and annual daily maximum peak flows were calculated for each combination. Modeled peak flows from the adjusted changes in temperature and precipitation were compared to unadjusted (historical) modeled peak flows. Annual daily maximum peak flows increase or decrease, depending on whether temperature or precipitation is adjusted; increases in air temperature (with no change in precipitation) lead to decreases in peak flows, whereas increases in precipitation (with no change in temperature) lead to increases in peak flows. As the magnitude of air temperatures increase in the four basins, peak flows decrease by larger amounts. If precipitation is held constant (no change from historical values), 17 to 26 percent decreases in peak flow occur at the four basins when temperature is increased by 7.2°F. If temperature is held constant, 26 to 38 percent increases in peak flow result from a 15-percent increase in precipitation. The largest decreases in peak flows at the four basins result from 15-percent decreases in precipitation combined with temperature increases of 10.8°F. The largest increases in peak flows generally result from 30-percent increases in precipitation combined with 3.6 °F decreases in temperatures. In many cases when temperature and precipitation both increase, small increases or decreases in annual daily maximum peak flows result. For likely changes projected for the northeastern United States for the middle of the 21st century (temperature increase of 3.6 °F and precipitation increases of 0 to 15 percent), peak-flow changes at the four coastal Maine basins in this study are modeled to be evenly distributed between increases and decreases of less than 25 percent. Peak flows with 50-percent and 1-percent AEPs (equivalent to 2-year and 100-year recurrence interval peak flows, respectively) were calculated for the four basins in the study using the PRMS-modeled annual daily maximum peak flows. Modeled peak flows with 50-percent and 1-percent AEPs with adjusted temperatures and precipitation were compared to unadjusted (historical) modeled values. Changes in peak flows with 50-percent AEPs are similar to changes in annual daily maximum peak flow; changes in peak flows with 1-percent AEPs are similar in pattern to changes in annual daily maximum peak flow, but some of the changes associated with increasing precipitation are much larger than changes in annual daily maximum peak flow. Substantial decreases in maximum annual winter snowpack water equivalent are modeled to occur with increasing air temperatures at the four basins in the study. (Snowpack is the snow on the ground that accumulates during a winter, and water equivalent is the amount of water in a snowpack if it were melted.) The decrease in modeled peak flows with increasing air temperature, given no change in precipitation amount, is likely caused by these decreases in winter snowpack and resulting decreases in snowmelt runoff. This Scientific Investigations Report, prepared in cooperation with the Maine Department of Transportation, presents a summary of modeled changes in peak flows at four basins in coastal Maine on the basis of projected changes in air temperature and precipitation. The full Fact Sheet (Hodgkins and Dudley, 2013) is available at http://pubs.usgs.gov/fs/2013/3021/.

Maine↗

An integrated approach for physical, economic, and demographic evaluation of coastal flood hazard adaptation in Santa Monica Bay, California

The increased risk of coastal flooding associated with climate-change driven sea level rise threatens to displace communities and cause substantial damage to infrastructure. Site-specific adaptation planning is necessary to mitigate the negative impacts of flooding on coastal residents and the built environment. Cost-benefit analyses used to evaluate coastal adaption strategies have traditionally focused on economic considerations, often overlooking potential demographic impacts that can directly influence vulnerability in coastal communities. Here, we present a transferable framework that couples hydrodynamic modeling of flooding driven by sea level rise and storm scenarios with site-specific building stock and census block-level demographic data. We assess the efficacy of multiple coastal adaptation strategies at reducing flooding, economic damages, and impacts to the local population. We apply this framework to evaluate a range of engineered, nature-based, and hybrid adaptation strategies for a portion of Santa Monica Bay, California. Overall, we find that dual approaches that provide protection along beaches using dunes or seawalls and along inlets using sluice gates perform best at reducing or eliminating flooding, damages, and population impacts. Adaptation strategies that include a sluice gate and partial or no protection along the beach are effective at reducing flooding around inlets but can exacerbate flooding elsewhere, leading to unintended impacts on residents. Our results also indicate trade-offs between economic and social risk-reduction priorities. The proposed framework allows for a comprehensive evaluation of coastal protection strategies across multiple objectives. Understanding how coastal adaptation strategies affect hydrodynamic, economic, and social factors at a local scale can enable more effective and equitable planning approaches.

California↗

Suspended sediment yield of New Jersey coastal plain streams draining into the Delaware estuary

An investigation was begun in 1965 by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers, Philadelphia District to meet the Corps’ need for information on sediment transport in the Delaware River basin in relation to the maintenance of navigable channels in the river 's estuarine areas. Sediment records were needed by the Corps to identify the principal sources and amounts of suspended sediment transported by New Jersey tributary streams into these estuarine areas. In order to meet the project's objective, a daily sediment sampling program at streamflow- gaging stations on Crosswicks Creek, Cooper River, Maurice River, and Raccoon Creek was established. Because of protracted drought, which resulted in unusually low sediment discharges, the period of data collection at these daily stations was extended. Upon reviewing these records, three partial-record stations were established on the Pennsauken, Big Timber, and Mantua Creeks in 1970 to complete the areal coverage. Records at two additional stations, Delaware River at Trenton and McDonalds Branch in Lebanon State Forest, collected as part of other cooperative projects were available also for use in this study. The purpose of this report is to summarize sediment data collected at selected stream-sampling sites in southern New Jersey. Computations of excepted average annual yields at each sampling site were made and utilized to estimate the annual yield at ungaged sites. Similar data currently are being compiled for streams draining Pennsylvania and Delaware. It is planned to report on the combined information at a later date in the Geological Survey's Water-Supply Paper series.

New Jersey↗

The value of marsh restoration for flood risk reduction in an urban estuary

The use of nature-based solutions (NBS) for coastal climate adaptation has broad and growing interest, but NBS are rarely assessed with the same rigor as traditional engineering solutions or with respect to future climate change scenarios. These gaps pose challenges for the use of NBS for climate adaptation. Here, we value the flood protection benefits of stakeholder-identified marsh restoration under current and future climate change within San Francisco Bay, a densely urbanized estuary, and specifically on the shores of San Mateo County, the county most vulnerable to future flooding in California. Marsh restoration provides a present value of 21 million dollars which increases to over 100 million dollars with 0.5 m of sea level rise (SLR), and to about 500 million dollars with 1 m of SLR. There are hotspots within the county where marsh restoration delivers very high benefits for adaptation, which reach 9 million dollars/hectare with likely future sea level and storm conditions. Today’s investments in nature and community resilience can result in increasing payoffs as climate change progresses and risk increases.

California↗

Phase 1 studies summary of major findings of the South Bay Salt Pond Restoration Project, South San Francisco Bay, California

Executive Summary The South Bay Salt Pond Restoration Project (Project) is one of the largest restoration efforts in the United States. It is located in South San Francisco Bay of California. It is unique not only for its size—more than 15,000 acres—but also for its location adjacent to one of the nation’s largest urban areas, home to more than 4 million people (Alameda, Santa Clara, and San Mateo Counties). The Project is intended to restore and enhance wetlands in South San Francisco Bay while providing for flood management, wildlife-oriented public access, and recreation. Restoration goals of the project are to provide a mosaic of saltmarsh habitat to benefit marsh species and managed ponds to benefit waterbirds, throughout 3 complexes and 54 former salt ponds. Although much is known about the project area, significant uncertainties remain with a project of this geographic and temporal scale of an estimated 50 years to complete the restoration. For example, in order to convert anywhere from 50 to 90 percent of the existing managed ponds to saltmarsh habitat, conservation managers first enhance the habitat of managed ponds in order to increase use by waterbirds, and provide migratory, wintering, and nesting habitat for more than 90 species of waterbirds. Project managers have concluded that the best way to address these uncertainties is to carefully implement the project in phases and learn from the outcome of each phase. The Adaptive Management Plan (AMP) identifies specific restoration targets for multiple aspects of the Project and defines triggers that would necessitate some type of management action if a particular aspect is trending negatively. U.S. Geological Survey (USGS) biologist Laura Valoppi served as the project Lead Scientist and oversaw implementation of the AMP in coordination with other members of the Project Management Team (PMT), comprised of representatives from the California State Coastal Conservancy, California Department of Fish and Wildlife, the Santa Clara Valley Water District, the U.S. Army Corps of Engineers, and the U.S. Fish and Wildlife Service. To implement the AMP, the PMT have selected and funded applied studies and monitoring projects to address key uncertainties. This information is used by the PMT to make decisions about current management of the project area and future restoration actions in order to meet project. This document summarizes the major scientific findings from studies conducted from 2009 to 2016, as part of the science program that was conducted in conjunction with Phase 1 restoration and management actions. Additionally, this report summarizes the management response to the study results under the guidance of the AMP framework and provides a list of suggested studies to be conducted in “Phase 2–A scorecard summarizing the Project’s progress toward meeting the AMP goals for a range of Project objectives.” The scoring to date indicates that the Project is meeting or exceeding expectations for sediment accretion and western snowy plover ( Charadrius alexandrinus nivosus ) recovery. There is uncertainty with respect to objectives for California gulls ( Larus californicus ), California least tern ( Sternula antillarum ), steelhead trout ( Oncorhynchus mykiss ), and regulatory water quality objectives. Water quality and algal blooms, specifically of the managed ponds, is indicated as trending negative. However, the vast majority of objectives are trending positive, including increased abundance for a number of bird guilds, increasing marsh habitat, maintenance of mudflats, visitor experience, estuarine fish numbers, and special-status marsh species numbers.

California↗

Environmental impact of oil development in northern Alaska

It is reported that in the spring of 1969 a high official of one of the oil companies was flying over the area of oil development in the vicinity of Prudhoe Bay. He is quoted as saying "If the American people could see what we are doing to their land here, they would want to abolish the use of the reciprocating engine." The last really large area of wilderness in the United States is the' Brooks Range and the Arctic Coastal Plain which stretches from that range to the Arctic Ocean. The proving of the exploratory oil wells which have been drilled on the coastal plain in the vicinity of Prudhoe Bay makes it virtually certain that this heretofore mostly unknown country will rapidly and vigorously be exposed to a variety of changes caused by the influx of men and their equipment. Even within the first four months of 1969 the whole aspect of the central part of the region has been importantly changed by the drilling programs of several large oil companies. So suddenly was this change brought about that no long-range plans have been developed either to soften the effect of such development on the natural environment or even to record the progress of these effects. Yet the absence of a plan provides an inadvertent potential advantage in that there has' been no history of increasingly firm Federal policy which, in other places, has often made it difficult to take newly conceived action in line with the increasing societal interest in environmental preservation. The lack of firm Federal policy provides here a unique opportunity for the application of new rules and investigative techniques aimed at minimizing the adverse effects on the environment while5.at the same time, not unduly hindering the development of the natural resources. But the speed with which the changes are being wrought makes it imperative that the principles applicable here to environmental protection or preservation, be enunciated immediately and that from these principles flow farsighted regulations which reflect the new interest in combining resource development with environmental protection. The present report constitutes a brief summary of the conditions existing in northern Alaska in the spring of 1969, presenting some inferences on the environmental changes which can be expected in the future and offering some specific steps which, if taken immediately and positively, could greatly ameliorate the adverse effects of rapid development in the absence of positive steps for environmental protection. In that regard, then, this report is ephemeral in character because the conditions in northern Alaska will surely change with great rapidity. Considering the"fragility and sensitivity of the ecosystems existing there, the changes can be both harsh and permanent. Therefore, whatever value lies in the recommendations made here., the results of their application will depend on the promptness of their consideration, amendment, and application. Whatever form the actions might take for minimizing the harm to the environment, the urgency of the matter can hardly be overestimated.

Alaska↗