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USGS2004

The effects of urbanization on the biological, physical, and chemical characteristics of coastal New England streams

During August 2000, responses of biological communities (invertebrates, fish, and algae), physical habitat, and water chemistry to urban intensity were compared among 30 streams within 80 miles of Boston, Massachusetts. Sites chosen for sampling represented a gradient of the intensity of urban development (urban intensity) among drainage basins that had minimal natural variability. In this study, spatial differences were used as surrogates for temporal changes to represent the effects of urbanization over time. The degree of urban intensity for each drainage basin was characterized with a standardized urban index (0-100, lowest to highest) derived from land cover, infrastructure, and socioeconomic variables. Multivariate and multimetric analyses were used to compare urban index values with biological, physical, and chemical data to determine how the data indicated responses to urbanization. Multivariate ordinations were derived for the invertebrate-, fish-, and algae-community data by use of correspondence analysis, and ordinations were derived for the chemical and physical data by use of principal-component analysis. Site scores from each of the ordinations were plotted in relation to the urban index to test for a response. In all cases, the primary axis scores showed the strongest response to the urban index, indicating that urbanization was a primary factor affecting the data ordination. For the multimetric analyses, each of the biological data sets was used to calculate a series of community metrics. For the sets of chemical and physical data, the individual variables and various combinations of individual variables were used as measured and derived metrics, respectively. Metrics that were generally most responsive to the urban index for each data set included: EPT (Ephemeroptera, Plecoptera, Trichoptera) taxa for invertebrates; cyprinid taxa for fish; diatom taxa for algae; bicarbonate, conductivity, and nitrogen for chemistry; and water depth and temperature for physical habitat. The slopes of the responses generally were higher between the urban index values of 0 to 35, indicating that the greatest change in aquatic health may occur between low and moderate levels of urban intensity. Additionally, many of the responses showed that at urban index values greater than 35, there was a threshold effect where the response variable no longer changed with respect to urban intensity. Recognizing and understanding this type of response is important in management and monitoring programs that rely on decisive interpretations of variable responses. Any biological, physical, or chemical variable that is used to characterize stream health over a gradient of disturbance would not be a reliable indicator when a level of disturbance is reached where the variable does not respond in a predictable manner.

Maine, Massachusetts, New Hampshire↗

USGS2020

Book review: Proceedings of the First International Snakehead Symposium

Snakehead fishes (family Channidae) are among the most maligned aquatic invasive species in the USA and some other countries where they have been introduced outside of their native range in Asia and Africa. Nevertheless, snakeheads continue to be widely exploited in the live‐food trade in aquaculture and wild‐capture fisheries, are highly sought by anglers, and are also popular in the aquarium trade (Courtenay and Williams 2004). The Northern Snakehead Channa argus is the most widespread of the three channid species that are currently naturalized in the USA. This species has generated much concern and controversy, a situation that is partly fueled by sensational media coverage and B‐grade science fiction horror films, such as “Frankenfish,” “Snakehead Terror,” and “Snakehead Swamp.” Media reports of snakehead introductions are often replete with provocative terms, such as “vicious,” “villain,” “voracious,” “monster,” “diabolical,” and even “ecological Armageddon.” When snakeheads first appeared in natural waters of the USA, fisheries professionals became increasingly interested in their status. Established populations rapidly expanded in the mid‐Atlantic region and Arkansas, with scattered reports of introduced snakeheads from isolated locations in Hawaii, California, North Carolina, Florida, the Upper Midwest, and New England. In 2002, snakeheads were added to the list of injurious fishes under the Lacey Act, thereby prohibiting their importation or transport across state lines without a permit. This symposium was conceived by the editors and other concerned fisheries professionals of the Mississippi River Basin Panel on Aquatic Invasive Species. The mission of the symposium, held in Alexandria, Virginia, in July 2018, was to bring together experts on snakehead biology and ecology and to synthesize existing information into summary papers. In this book, 35 authors contributed to 15 peer‐reviewed articles that detail the current state of knowledge about snakehead introductions in the USA. Additionally, 16 abstracts are included from meeting presentations that were not accompanied by full‐length manuscripts. Also included is a summary of a facilitated symposium panel discussion featuring eight experts representing state and federal natural resource agencies and private fishing organizations. The book is organized into six sections. In the first section (Distribution), three papers provide an overview of the Channa species introduced into the USA and historical accounts of occurrence and dispersal of the Northern Snakehead in the mid‐Atlantic region and Arkansas. The second section (Biology/Ecology) consists of two articles that examine growth and energetics of Northern Snakehead populations and two papers that investigate diet, diel feeding activity, and movement of this species in the Potomac River drainage. The third section (Monitoring/Response) includes a paper that models range expansion of the Northern Snakehead in the southeastern USA based on occurrence data and environmental conditions. Also included in this section is a paper summarizing an environmental DNA study to assess the status and range of the Bullseye Snakehead C. marulius in southern Florida. The fourth section (Management/Control) is comprised of four papers that address harvest, age and growth, and development of a stock–recruitment model to inform management decisions regarding control and mitigation for Northern Snakehead populations in the greater Chesapeake Bay area. The fifth section (Perspectives) includes a paper on the history of snakehead introductions in Japan and a thought‐provoking social commentary on the human dimensions of Northern Snakehead management. Abstracts in the final section provide brief summaries of a diversity of snakehead studies, including aspects of distribution, ecology, behavior, control and monitoring efforts, public outreach, and pathology. The summary of the panel discussion is an engaging dialogue about the challenges of snakehead management in the context of conflicts regarding snakeheads as injurious versus their value as game and food species. Most of this book is focused on the Northern Snakehead. Much has been done to document snakehead distributions and certain aspects of snakehead biology, such as diets, age, and growth. Less research has been devoted to understanding the ecological impacts of snakeheads to native aquatic communities and ecosystems. This book would have benefited from a chapter summarizing the current systematics and diversity of the Channidae to inform fisheries biologists about the morphological characteristics of the family, approximate numbers of genera and species, and taxonomic instability. Exemplifying the latter, recent molecular and morphological evidence indicates uncertainty regarding identification of the feral snakehead population in Florida (Adamson and Britz 2019). Those authors suggest that this population may have originated from western Thailand, a possibility that could have implications for understanding historical pathways of snakehead introductions into the USA. In comparison with many published AFS symposia, this volume is relatively narrow in scope and lacks cohesive integration. It will primarily be of interest to those fisheries professionals engaged in the study of snakeheads as well as other nonnative species for which there are contrasting social values regarding their management: whether to monitor and attempt control or eradication efforts or to maintain populations for harvest as game or food species. The book should serve to identify information gaps and guide future research.

Transactions of the American Fisheries Society↗

USGS1974

Water quality of hydrologic bench marks; an indicator of water quality in the natural environment

Water-quality data, collected at 57 hydrologic bench-mark stations in 37 States, allow the definition of water quality in the 'natural' environment and the comparison of 'natural' water quality with water quality of major streams draining similar water-resources regions. Results indicate that water quality in the 'natural' environment is generally very good. Streams draining hydrologic bench-mark basins generally contain low concentrations of dissolved constituents. Water collected at the hydrologic bench-mark stations was analyzed for the following minor metals: arsenic, barium, cadmium, hexavalent chromium, cobalt, copper, lead, mercury, selenium, silver, and zinc. Of 642 analyses, about 65 percent of the observed concentrations were zero. Only three samples contained metals in excess of U.S. Public Health Service recommended drinking-water standards--two selenium concentrations and one cadmium concentration. A total of 213 samples were analyzed for 11 pesticidal compounds. Widespread but very low-level occurrence of pesticide residues in the 'natural' environment was found--about 30 percent of all samples contained low-level concentrations of pesticidal compounds. The DDT family of pesticides occurred most commonly, accounting for 75 percent of the detected occurrences. The highest observed concentration of DDT was 0.06 microgram per litre, well below the recommended maximum permissible in drinking water. Nitrate concentrations in the 'natural' environment generally varied from 0.2 to 0.5 milligram per litre. The average concentration of nitrate in many major streams is as much as 10 times greater. The relationship between dissolved-solids concentration and discharge per unit area in the 'natural' environment for the various physical divisions in the United States has been shown to be an applicable tool for approximating 'natural' water quality. The relationship between dissolved-solids concentration and discharge per unit area is applicable in all the physical divisions of the United States, except the Central Lowland province of the Interior Plains, the Great Plains province of the Interior Plains, and the Basin and Ridge province of the Intermontane Plateaus. The relationship between dissolved-solids concentration and discharge per unit area is least variable in the New England province and Blue Ridge province of the Appalachian Highlands. The dissolved-solids concentration versus discharge per unit area in the Central Lowland province of the Interior Plains is highly variable. A sample collected from the hydrologic bench-mark station at Bear Den Creek near Mandaree, N. Dak., contained 3,420 milligrams per litre dissolved solids. This high concentration in the 'natural' environment indicates that natural processes can be principal agents in modifying the environment and can cause degradation. Average annual runoff and rock type can be used as predictive tools to determine the maximum dissolved-solids concentration expected in the 'natural' environment.

Circular↗

USGS1996

Biological control of marine pests

Biological control, as used in terrestrial systems, may hold promise for use against exotic marine species. We first review some marine pests, displaying their diversity, the damage they cause, and possible controls. We then contrast approaches for marine and terrestrial pest control, providing guidelines for adapting terrestrial controls to the marine environment. Although several of the same principles apply in terrestrial and marine environments, marine systems differ with respect to the types of control agents available, the degree of pest—population reduction needed for effective control, the spatial scale over which biological control must operate effectively, the practicality of implementation, and the nature and degree of concern over safety. As an example, we propose a strategy for developing a biological control program against the European green crab, Carcinus maenas, which has had substantial negative impacts where previously introduced (New England, Atlantic Canada, South Africa, south Australia) and which has recently been introduced to central California, and to Tasmania. We conclude that biological control may be possible for some marine pests, but that existing strategies and expectations will require modification.

Ecology↗

USGS2013

Geomorphic and human influence on large-scale coastal change

An increasing need exists for regional-scale measurements of shoreline change to aid in management and planning decisions over a broad portion of the coast and to inform assessments of coastal vulnerabilities and hazards. A recent dataset of regional shoreline change, covering a large portion of the U.S. East coast (New England and Mid-Atlantic), provides rates of shoreline change over historical (~ 150 years) and recent (25–30 years) time periods making it ideal for a broad assessment of the regional variation of shoreline change, and the natural and human-induced influences on coastal behavior. The variable coastal landforms of the region provide an opportunity to investigate how specific geomorphic landforms relate to the spatial variability of shoreline change. In addition to natural influences on the rates of change, we examine the effects that development and human modifications to the coastline have on the measurements of regional shoreline change. Regional variation in the rates of shoreline change is a function of the dominant type and distribution of coastal landform as well as the relative amount of human development. Our results indicate that geomorphology has measurable influence on shoreline change rates. Anthropogenic impacts are found to be greater along the more densely developed and modified portion of the coast where jetties at engineered inlets impound large volumes of sediment resulting in extreme but discrete progradation updrift of jetties. This produces a shift in averaged values of rates that may mask the natural long-term record. Additionally, a strong correlation is found to exist between rates of shoreline change and relative level of human development. Using a geomorphic characterization of the types of coastal landform as a guide for expected relative rates of change, we found that the shoreline appears to be changing naturally only along sparsely developed coasts. Even modest amounts of development influence the rates of change and the human imprint override the geomorphic signal. The study demonstrates that human activities associated with creating and maintaining coastal infrastructure alter the natural behavior of the coast over hundreds of kilometers and time spans greater than a century. This suggests that future assessments of vulnerability, based largely on rates of change along developed coastlines, need to take the role of human alterations into account.

Geomorphology↗

USGS2005

Arsenic in ground water of the United States: occurrence and geochemistry

Concentrations of naturally occurring arsenic in ground water vary regionally due to a combination of climate and geology. Although slightly less than half of 30,000 arsenic analyses of ground water in the United States were 1 μg/L, about 10% exceeded 10 μg/L. At a broad regional scale, arsenic concentrations exceeding 10 μg/L appear to be more frequently observed in the western United States than in the eastern half. Arsenic concentrations in ground water of the Appalachian Highlands and the Atlantic Plain generally are very low ( 1 μg/L). Concentrations are somewhat greater in the Interior Plains and the Rocky Mountain System. Investigations of ground water in New England, Michigan, Minnesota, South Dakota, Oklahoma, and Wisconsin within the last decade suggest that arsenic concentrations exceeding 10 μg/L are more widespread and common than previously recognized. Arsenic release from iron oxide appears to be the most common cause of widespread arsenic concentrations exceeding 10 μg/L in ground water. This can occur in response to different geochemical conditions, including release of arsenic to ground water through reaction of iron oxide with either natural or anthropogenic (i.e., petroleum products) organic carbon. Iron oxide also can release arsenic to alkaline ground water, such as that found in some felsic volcanic rocks and alkaline aquifers of the western United States. Sulfide minerals are both a source and sink for arsenic. Geothermal water and high evaporation rates also are associated with arsenic concentrations 10g/L in ground and surface water, particularly in the west. Arsenic release from iron oxide appears to be the most common cause of widespread arsenic concentrations exceeding 10 µg/L a ground water. This can occur in response to different geochemical conditions, including release of arsenic to ground water through reaction of iron oxide with either natural or anthropogenic (i.e., petroleum products) organic carbon. Iron oxide also can release arsenic to alkaline ground water, such as that found in some felsic volcanic rocks and alkaline aquifers of the Western United States. Sulfide minerals are both a source and sink for arsenic. Geothermal water and high evaporation rates also are associated with arsenic concentrations ≥ 10g/L in ground and surface water, particularly in the west.

Ground Water↗

USGS2004

Comparison of methods for determining streamflow requirements for aquatic habitat protection at selected sites on the Assabet and Charles Rivers, Eastern Massachusetts, 2000-02

Four methods used to determine streamflow requirements for habitat protection at nine critical riffle reaches in the Assabet River and Charles River Basins were compared. The methods include three standard setting techniques?R2Cross, Wetted Perimeter, and Tennant?and a diagnostic method, the Range of Variability Approach. One study reach is on the main stem of the Assabet River, four reaches are on tributaries to the Assabet River (Cold Harbor Brook, Danforth Brook, Fort Meadow Brook, and Elizabeth Brook), three are on the main stem of the Charles River, and one is on a tributary to the Charles River (Mine Brook). The strength of the R2Cross and Wetted-Perimeter methods is that they may be applied at ungaged locations whereas the Tennant method and the Range of Variability Approach require a period of streamflow record for analysis. Fish community assessments conducted at or near riffle sites in flowing reaches of the Assabet River and Charles River Basins were used to indicate ecological conditions. The fish communities in the main stem and tributary reaches of both the Assabet and Charles River Basins indicated degraded aquatic ecosystems. However, the degree of degradation differs between the two basins. The extreme predominance of tolerant, generalist species in the Charles River fish community demon-strates the cumulative impacts of flow, habitat, and water-chemistry degradation, combined with the effects of nearby impoundments and changing land use. The range of discharges for nine ungaged riffle reaches defined by the median R2Cross 3-of-3 criteria, R2Cross 2-of-3 criteria, and Wetted-Perimeter streamflow requirements, was 0.86 cubic foot per second per square mile, 0.18 cubic foot per second per square mile, and 0.23 cubic foot per second per square mile, respectively. Application of R2Cross and Wetted-Perimeter methods to sites with altered streamflows or at sites that are riffles only at low to moderate flows can result in a greater variability of streamflow requirements than would result if the methods were applied to riffles on natural channels with unaltered streamflows. The R2Cross 2-of-3 criteria and the Wetted-Perimeter streamflow requirements for the Assabet and Charles River sites show narrower interquartile ranges and lower median streamflow requirements than for 10 index streamflow-gaging stations in southern New England. This is especially evident for the R2Cross 2-of-3 criteria and Wetted-Perimeter results that were close to half of the flow requirements determined at the 10 southern New England stations. The R2Cross and Wetted-Perimeter methods were also compared to the Range of Variability Approach analysis and the Tennant Method. The median R2Cross 3-of-3 criteria streamflow requirement for the nine riffles is close to the 75th percentile of the monthly mean flows during the summer low-flow period from six streamflow-gaging stations near the Assabet and Charles River Basins having mostly unaltered flow. This streamflow requirement is close to the median Tennant 40-percent-flow requirement for good habitat condi-tion for the same six nearby stations. The R2Cross 2-of-3 criteria and Wetted-Perimeter results were less than the 25th-percentile of monthly mean flows during the summer months for the six stations. These streamflow requirements are in the poor habitat range as indicated by a Tennant analysis of the same six stations. These comparisons indicate that the R2Cross and Wetted-Perimeter methods underestimate streamflow requirements when applied to sites in smaller drainage areas and channels that are runs at higher flows.

Scientific Investigations Report↗

USGS2003

Assessment of forest fragmentation in southern New England using remote sensing and geographic information systems technology

Spatial patterns and rates of forest fragmentation were assessed using digital remote sensing data for a region in southern New England that included 157 townships in southern New Hampshire and northeastern Massachusetts. The study area has undergone marked population increases over the last several decades. Following classification of 1973 and 1988 Landsat Multispectral Scanner data into forest and nonforest classes, data were incorporated into a geographic information system. The natural logarithms of forest area to perimeter ratios, referred to as the forest continuity index, were used to assess patterns and trends of forest fragmentation across the region Forest continuity index values were extracted from each township for both data sets and compared with population data. Forest continuity index values were found to decrease with increasing population density until about 200 persons per square kilometer, after which the relationship stabilized. With slight population increases at low densities forest continuity index values declined sharply, implying abrupt increases in forest fragmentation. Results from the study indicated good negative correlations (r 2 values of 0.81 and 0.77) between the Multispectral Scanner-derived forest continuity index and natural logs of township population density. Socioeconomic indicators such as affluence and commuting patterns did not appear to correlate well with forest fragmentation estimates. Decreases in forest continuity index values occurred throughout much of the study region between 1973 and 1988, suggesting that forest fragmentation is occurring over large regions within the eastern United States. It is technologically feasible to assess patterns and rates of forest fragmentation across much larger areas than analyzed in this study; such analyses would provide useful overviews enabling objective assessment of the magnitude of forest fragmentation.

Massachusetts, New Hampshire↗

USGS2007

Rock-Bound Arsenic Influences Ground Water and Sediment Chemistry Throughout New England

The information in this report was presented at the Northeastern Region Geological Society of America meeting held March 11-14, 2007, in Durham, New Hampshire. In the New England crystalline bedrock aquifer, concentrations of arsenic that exceed the drinking water standard of 10 ?g/L occur most frequently in ground water from wells sited in specific metamorphic and igneous rock units. Geochemical investigations indicate that these geologic units typically have moderately elevated whole-rock concentrations of arsenic compared to other rocks in the region. The distribution of ground water wells with As > 5 ?g/L has a strong spatial correlation with specific bedrock units where average whole-rock concentrations of arsenic exceed 1.1 mg/kg and where geologic and geochemical factors produce high pH ground water. Arsenic concentrations in stream sediments collected from small drainages reflect the regional distribution of this natural arsenic source and have a strong correlation with both rock chemistry and the distribution of bedrock units with elevated arsenic chemistry. The distribution of ground water wells with As > 5 ?g/L has a strong spatial correlation with the distribution of stream sediments where concentrations of arsenic exceed 6 mg/kg. Stream sediment chemistry also has a weak correlation with the distribution of agricultural lands where arsenical pesticides were used on apple, blueberry, and potato crops. Elevated arsenic concentrations in bedrock wells, however, do not correlate with agricultural areas where arsenical pesticides were used. These results indicate that both stream sediment chemistry and the solubility and mobility of arsenic in ground water in bedrock are influenced by host-rock arsenic concentrations. Stream sediment chemistry and the distribution of geologic units have been found to be useful parameters to predict the areas of greatest concern for elevated arsenic in ground water and to estimate the likely levels of human exposure to elevated arsenic in drinking water in New England. However, the extreme local variability of arsenic concentrations in ground water from these rock sources indicate that arsenic concentrations in ground water are affected by other factors in addition to arsenic concentrations in rock.

Open-File Report↗

USGS1972

Clay deposits of the Connecticut River Valley, Connecticut: a special problem in land management

When man first settled the United States, two natural features favored settlement; flat land that was easy to build on and to farm, and a nearby river that could act as a source of water, transportation, and power. The Connecticut River Valley from Middletown, Ct. north past the Connecticut-Massachusetts state line satisfied these two needs, and was favored by many early Americans in New England. This area remains an area of rapid urbanization, partly because of the broad flat lowlands. The subdued topography of this area is due in large part to deposition of fine-grained materials into glacial Lake Hitchcock. This lake was formed during the Wisconsinan age when southward drainage in the Triassic valley of Connecticut was dammed by glacial drift in the area of Rocky Hill, Connecticut. Lake Hitchcock grew to and beyond St. Johnsbury, Vt. with much of the lake being filled with cyclical lake-bottom deposits during the 2,290 to 2,350 years of its life. Aside from the relative flatness inherent in the deposition of fine-grained lake-bottom deposits, these deposits present very few characteristics that are favorable for urbanization. Favorable characteristics are possible sources of clay for manufacturing and possible sources for waste storage sites. Unfavorable characteristics include low water yields resulting in poor urban water-supply sources, and very low flows in streams during dry periods; low percolation rates resulting In drainage and septic problems; and low or uneven bearing strength which create problems in construction. Fine-grained lake-bottom deposits have been mapped for six quadrangles in the Connecticut Valley lowlands; the quadrangles of Windsor Locks, Broad Brook, Hartford North, Manchester, Hartford South, and Glastonbury (all located in Connecticut). All the maps were prepared from existing information including well and test hole data on file at the Water Resources Division in Hartford, surficial geologic quadrangle maps, and bedrock contour maps. The maps also reflect geologic interpretations of the history of glacial Lake Hitchcock. The Hartford North maps were prepared as test maps to determine if the project was feasible. They were prepared using the previously described information plus additional subsurface data obtained from engineering firms and the State Highway Department. During preparation of the maps, an arcuate-shaped, ice-contact deposit composed of coarse sand and gravel was delineated in the Broad Brook and Windsor Locks quadrangles. This feature marks the location of a zone of stagnant ice In front of and marginal to active ice to the north. Two types of maps were prepared for the area in study; Thickness of the Principal Clay Deposit, and Thickness of Material Overlying the Principal Clay Deposit. The term "principal clay deposit" refers to the fine-grained lake-bottom deposits of Glacial Lake Hitchcock. These maps define the distribution of the deposit, and show the thickness of the deposit in 50 foot intervals and the thickness of the material overlying the deposit In 20 foot intervals. The maps indicate that much of the area is underlain with substantial thicknesses of finegrained lake-bottom deposits (50 feet thick or greater), and that much of the deposit is within 20 feet of the surface. The maps included in this report can be used for land-use planning. Uses include location of favorable sites for specific uses such as landfills, utility corridors, heavy construction, etc; location of problem areas for specific land uses; identification of possible problems for specific areas; design and construction cost estimates; and prospecting for exploitable clay deposits. It Is suggested that, for effective planning, these maps be used together or in conjunction with other maps such as maps showing surface materials, depth to bedrock, depth to water table, and flood prone areas.

Connecticut↗

USGS1996

Water-quality assessment of the Connecticut, Housatonic, and Thames River Basins study unit: Analysis of available data on nutrients, suspended sediments, and pesticides, 1972-92

This retrospective report examines available nutrient, suspended sediment, and pesticide data in surface and ground water in the Connecticut, Housatonic and Thames Rivers Study Unit of the National Water-Quality Assessment Program. The purpose of this study is to improve the understanding of natural and anthropogenic factors affecting water quality in the study unit. Waterquality data were acquired from various sources, primarily, the U.S. Geological Survey and the U.S. Environmental Protection Agency. The report examines data for water years 1972-92, focusing on 1980-92, although it also includes additional data from as early as 1905. The study unit lies within the New England Physiographic Province and altitudes range from sea level in coastal Connecticut to 6,288 feet above sea level at Mount Washington, New Hampshire. Two major aquifer types underlie the study unit unconsolidated glacial deposits and fractured bedrock. The climate generally is temperate and humid, with four distinct seasons. Average annual precipitation ranges from 34 to 65 inches. The study unit has a population of about 4.5 million, which is most highly concentrated in southwestern Connecticut and along the south-central region of the Connecticut River Valley. Surface-water-quality data were screened to provide information about sites with adequate numbers of analyses (50) over sufficiently long periods (1980-90) to enable valid statistical analyses. In order to compare effects of different types of land use on surface-water quality, examination of data required application of several statistical and graphical techniques, including mapping, histograms, boxplots, concentration-discharge plots, trend analysis, and load estimation. Spatial and temporal analysis of surface-water-quality data indicated that, with a single exception, only stations in the Connecticut water-quality network had sufficient data collected over adequately long time periods to use in detailed analyses. Ground-water nutrient and pesticide data were compiled from several Federal and State agencies, primarily the U.S. Geological Survey, U.S. Environmental Protection Agency, and Connecticut Department of Health Services. Nutrient data were available for several thousand wells; nitrite plus nitrate as nitrogen was the most commonly reported constituent. Most wells with nutrient data are in Massachusetts and Connecticut. Relative to nutrient data in ground and surface water, pesticide data are less common. Pesticide data were available for slightly more than 200 surface-water sites and less than 500 wells; about 95 percent of the wells are completed in stratified-drift or till aquifers. Data for 81 pesticide compounds were available in various data bases. 2,4-D and silvex were the most commonly detected herbicides in surface water and dieldrin and diazinon were the most commonly detected insecticides. Most surface-water pesticide samples and detections are from bed sediment, but much of the data are not recent. Ethylene dibromide (EDB), a soil fumigant used in tobacco farming was detected in 268 wells in a 50 square-mile area of north-central Connecticut; EDB contamination also was detected in wells in Massachusetts. Atrazine, an herbicide commonly used in corn farming, commonly was detected in wells installed in tilled agricultural fields. Corn herbicides were commonly detected in the northern part of the study unit, although the sampling has been less frequent than in the southern part of the study unit. Pesticides were seldom detected in public-supply wells in Connecticut. Urban sites with relatively high population densities and high concentrations of dischargers were characterized by having the highest nutrient concentrations and loads when adjusted for differences in drainage area or population. Particularly, the Pequabuck, Naugatuck, and Quinnipiac River Basins were characterized by high nutrient concentrations median total nitrogen concentrations ranged from 3.3 to 4.2 mg/L (milligrams per liter) and median total phosphorus concentrations ranged from 0.42 to 0.8 mg/L. In contrast, the predominantly forested and low density residential land-use sites, such as Saugatuck and Salmon River Basins, were characterized by low nutrient concentrations median total nitrogen ranged from 0.50 to 0.60 mg/L and median total phosphorus concentrations ranged from 0.01 to 0.02 mg/L. Estimated total nitrogen loadings in median discharge years ranged from 940 kilograms per square mile at the Salmon River near East Hampton, Conn., to 5,800 kilograms per square mile at the Naugatuck River at Beacon Falls, Conn. Water quality, in terms of nutrient concentrations and areally adjusted loadings, for sites with large drainage basins integrating a wide variety of land-use categories fell between the extremes of the urban and forested sites total nitrogen was 1,400 kilograms per square mile per year at the Connecticut River at Thompsonville, Conn. Nitrate concentrations in ground water occasionally exceeded the safe drinking-water standard of 10 mg/L as nitrogen. The greatest number of detections exceeding the standard, however, were not in public-water supplies but in shallow observation wells in agricultural settings (the most frequently sampled type of well). None of the public-supply wells in Massachusetts exceeded the standard. Although nitrate concentrations for Vermont and New Hampshire generally were low, few data were available and those were seldom reported on the basis of drainage basin, making analysis difficult. Trend analysis indicated that flow-adjusted concentrations of total and dissolved phosphorus generally decreased during the period of analysis, however, total nitrogen did not change substantially. Decreases in ammonia concentrations with time were usually accompanied by increases in nitrate, suggesting improvements in sewage treatment. The lack of adequate data from more or less exclusively agricultural areas points to the need for further study of the effects of fanning on surface-water quality in the study unit. Furthermore, additional information is needed on the rates, transformations, and movements of nutrients and other materials through and between the aquatic and terrestrial components of the study unit.

Connecticut, Massachusetts, New Hampshire, Quebec,↗

USGS2001

Minimum age of the Neoproterozoic Seven Hundred Acre Island Formation and the tectonic setting of the Islesboro Formation, Islesboro block, Maine

Two plat formal stratigraphic sequences occur on Islesboro, Penobscot Bay, Maine. The older Seven Hundred Acre Island Formation is at least 200 m thick, its base is not exposed, and it makes up fault-bounded blocks of siliceous colour-banded dolomitic marble, muscovite-rich quartzite, coarse-grained splendent muscovite-garnet-staurolite-andalusite schist, and calcareous metapelite, with minor garnet amphibolite and amphibolite. It was initially metamorphosed to lower amphibolite facies and was later retrograded to lower greenschist facies. The lower amphibolite facies metamorphism is Neoproterozoic (670 to 650 Ma) as inferred from the 40 Ar/ 39 Ar high temperature release spectra of hornblende separates. A U-Pb zircon age of 646.7 ± 2.7 Ma obtained for a pegmatite that intruded deformed rocks is taken to be the minimum age of the Formation. The platformal Islesboro Formation probably unconformably overlies the Seven Hundred Acre Island Formation. It is primarily turbiditic pelite with many beds of quartzite, impure dolomitic marble, some conglomerate, and a few feldspar-rich volcaniclastic beds and is thought to be either Neoproterozoic or Cambrian. It was metamorphosed only to lower greenschist facies, possibly in the same event that retrograded the Seven Hundred Acre Island Formation. Geochemical interpretations of minor and trace element analyses of six amphibolite and four schist samples from the Seven Hundred Acre Island Formation show that the protoliths of the amphibolite samples were intermediate between tholeiitic and within-plate type basaltic flows or dikes that intruded attenuated continental crust, or were eroded from these basalts. Four amphibolite and three schist samples analyzed for Pb isotopes were found to be enriched in radiogenic Pb. The Pb isotopic compositions are similar to those in peri-Gondwanan basement rocks from Atlantic Canada. The peri-Gondwanan Islesboro block was placed against the peri-Gondwanan Middle and Late Cambrian Ellsworth terrane on the cast by significant Late Silurian strike-slip faulting. The Late Silurian or Early Devonian Turtle Head dextral strike-slip fault separates the Islesboro block from the peri-Gondwanan St. Croix terrane to the west. The timing and nature of the movements of these faults are given from offsets of the isograds around the zircon-dated Laic Silurian Sedgwick Granite (419.5 ± 1.4 Ma) and South Penobscot Intrusive Suite (419.2 ± 2.2 Ma). These terranes and others like them in Atlantic Canada make up a composite terrane that is different from the composite Avalonian terranes sensu stricto of southeastern New England and Atlantic Canada. The composite peri-Gondwanan terrane that included the Islesboro block was amalgamated with the margin of ancestral North America in the Silurian.

Maine↗

USGS2020

Spatially referenced models of streamflow and nitrogen, phosphorus, and suspended-sediment loads in streams of the northeastern United States

SPAtially Referenced Regression On Watershed attributes (SPARROW) models were developed to quantify and improve the understanding of the sources, fate, and transport of nitrogen, phosphorus, and suspended sediment in the northeastern United States. Excessive nutrients and suspended sediment from upland watersheds and tributary streams have contributed to ecological and economic degradation of northeastern surface waters. Recent efforts to reduce the flux of nutrients and suspended sediment in northeastern streams and to downstream estuaries have met with mixed results, and expected ecological improvements have been observed in some areas but not in others. Effective watershed management and restoration to improve surface-water quality are complicated by the multitude of nutrient sources in the Northeast and the multitude of natural and human landscape processes affecting the delivery of nutrients and suspended sediment from upland areas to and within surface waters. Individual models were constructed representing streamflow and the loads of total nitrogen, total phosphorus, and suspended sediment from watersheds draining to the Atlantic Ocean from southern Virginia through Maine. Northeastern streams contribute 303,000 metric tons (t) of nitrogen, 25,300 t of phosphorus, and 14,700,000 t of suspended sediment, annually (on average), to waters along the Atlantic Coast of North America. Although atmospheric deposition and natural mineral erosion contribute to nitrogen and phosphorus loads, respectively, in northeastern streams, most of the contributions are attributable to urban or agricultural sources. Within the Northeast, average yields of nutrients are therefore generally greater from densely populated or intensively cultivated areas of the mid-Atlantic region, the Hudson, Mohawk, and Connecticut River valleys, and the coastal areas of southern New England than in predominantly forested areas such as northern New England. Average upland sediment yields are similarly greater from agricultural areas than from urban or forested areas and are therefore generally greatest in areas yielding the greatest nutrients. Landscape conditions that are significant to nitrogen delivery from uplands to streams likely reflect the importance of groundwater transport in carbonate settings and of denitrification for removing nitrogen from uplands. Nitrogen losses to streams in agricultural areas are apparently mitigated by the use of cover crops but are exacerbated by the use of conservation tillage or no-till practices. The transport of phosphorus and suspended sediment from uplands to streams is greater in areas of more erodible soils but mitigated in agricultural areas with greater use of conservation tillage or no-till practices. Loads of nutrients and suspended sediment are significantly reduced within the stream network in impounded reaches, and nitrogen load is also significantly reduced in small flowing reaches.

Scientific Investigations Report↗

USGS2010

Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: NLCD 2001 Tree Canopy

This tabular data set represents the mean percent tree canopy from the Canopy Layer of the National Land Cover Dataset 2001 (LaMotte and Wieczorek, 2010), compiled for every MRB_E2RF1 catchment of Major River Basins (MRBs, Crawford and others, 2006). The source data set represents tree canopy percentage for the conterminous United States for 2001. The Canopy Layer of the National Land Cover Data Set for 2001 was produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of Federal agencies (http://www.mrlc.gov), consisting of the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the U.S. Environmental Protection Agency (USEPA), the U.S. Department of Agriculture (USDA), the U.S. Forest Service (USFS), the National Park Service (NPS), the U.S. Fish and Wildlife Service (USFWS), the Bureau of Land Management (BLM), and the USDA Natural Resources Conservation Service (NRCS). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

Data Series↗

USGS2010

Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: NLCD 2001 Imperviousness

This tabular data set represents the mean percent impervious surface from the Imperviousness Layer of the National Land Cover Dataset 2001, (LaMotte and Wieczorek, 2010), compiled for every MRB_E2RF1 catchment of selected Major River Basins (MRBs, Crawford and others, 2006). The source data set represents imperviousness for the conterminous United States for 2001. The Imperviousness Layer of the National Land Cover Data Set for 2001 was produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of Federal agencies (http://www.mrlc.gov), consisting of the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the U.S. Environmental Protection Agency (USEPA), the U.S. Department of Agriculture (USDA), the U.S. Forest Service (USFS), the National Park Service (NPS), the U.S. Fish and Wildlife Service (USFWS), the Bureau of Land Management (BLM), and the USDA Natural Resources Conservation Service (NRCS). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002;Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

Data Series↗

USGS1937

The floods of March 1936, part 1, New England rivers

During the period March 9-22, 1936, there occurred in close succession over the northeastern United States, from the James and upper Ohio River Basins in Virginia and Pennsylvania to the river basins of Maine, two extraordinarily heavy storms, in which the precipitation was almost entirely in the form of rain. The depths of rainfall mark this period as one of the greatest concentrations of precipitation, in respect to time and magnitude of the area covered, of which there is record in this country. At the time of the rain there were also accumulations of snow on the ground over much of the storm-affected region that were large for the season. The comparatively warm temperatures associated with the storms thawed the snow and added materially to the quantities of water to be disposed of by drainage into the waterways, by surface storage in lakes, ponds, and reservoirs, by absorption in the ground, and, probably in comparatively negligible degree, by evaporation. The total quantity of water that had to be disposed of in these ways ranged between 10 and 30 inches in depth over much of the region. The water disposed of by natural storage, absorption, and evaporation amounted to average depths over the many river basins generally within the range of 1 to 3 inches, with a significant degree of uniformity and systematic areal distribution. The remainder of the rain and snow water, generally much larger or even several times larger in amount than surface storage, absorption, and evaporation, required accommodation by the channels of the brooks, creeks, and rivers. There were generally two distinct flood peaks, and in many of the basins the destruction was seriously aggravated, especially during the first flood, by the break-up of thick ice cover accumulated through a winter of exceptionally continuous and severe cold weather. The resulting floods were extraordinarily severe, and records of river stages, extending on some streams back to or nearly to the time of settlement by white men, were broken many of them by wide margins. The peak of the Connecticut River at Hartford, Conn., was 8.6 feet higher than had been experienced since the settlement by white men, 300 years ago. The Susquehanna River at Harrisburg, Pa., was 3.5 feet higher than had been known in a period of record covering about 200 years. The Ohio River at Pittsburgh, Pa., was 6.1 feet higher than had been known in the period beginning 1762. This volume presents many of the facts of these notable floods with respect to the New England rivers, for permanent record and for study and reference by engineers concerned with the building of highways, bridges, and industrial plants, planners of river development, and others. Similar volumes for the region from the Hudson River to the Susquehanna River and for the Potomac, James, and upper Ohio River Basins are presented in companion Water-Supply Papers 799 and 800 respectively. In this volume records of stage and discharge for the period Including the floods are presented for about 150 measurement stations; peak discharges with comparative data for other floods at more than 400 measurement points are summarized; crest stages along an aggregate length of stream channel of 2,820 miles are tabulated; and results of detailed studies of the rainfall and run-off and many other kinds of flood information are presented.

Water Supply Paper↗

USGS2019

Tidal erosion and upstream sediment trapping modulate records of land-use change in a formerly glaciated New England estuary

Land clearing, river impoundments, and other human modifications to the upland landscape and within estuarine systems can drive coastal change at local to regional scales. However, as compared with mid-latitude coasts, the impacts of human modifications along sediment-starved formerly glaciated coastal landscapes are relatively understudied. To address this gap, we present a late-Holocene record of changing sediment accumulation rates and sediment sources from sediment cores collected across a tidal flat in the Merrimack River estuary (Mass., USA). We pair sedimentology, geochronology, bulk- and stable-isotope organic geochemistry, and hydrodynamic simulations with historical data to evaluate human and natural impacts on coastal sediment fluxes. During the 17th to 19th centuries, accumulation rates increased by an order of magnitude in the central tidal flat, likely in response to enhanced delivery of terrestrial sediment resulting from upland deforestation. However, the overall increase in accumulation (0.56–2.6 mm/year) within the estuary is subtle and spatially variable across the tidal flats because of coincident anthropogenic land clearing and dam building, upland sediment storage, and estuarine hydrodynamics. This study provides insight into the response of formerly glaciated fluvial-coastal systems to human modifications, and underscores the role of estuarine environmental conditions in modifying upland signals of land-use change.

Massachusetts, New Hampshire↗

USGS2010

Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Estimated Mean Annual Natural Groundwater Recharge, 2002

This tabular data set represents the mean annual natural groundwater recharge, in millimeters, compiled for every MRB_E2RF1catchment of selected Major River Basins (MRBs, Crawford and others, 2006). The source data set is Estimated Mean Annual Natural Ground-Water Recharge in the Conterminous United States (Wolock, 2003). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

Data Series↗