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USGS1993

The Effect of mining and related activities on the sediment-trace element geochemistry of Lake Coeur d'Alene, Idaho, U.S.A.; Part II, Subsurface sediments

During the summer of 1990, 12 gravity cores were collected in Lake Coeur d'Alene, Idaho, at various depths and in a variety of depositional environments. All core subsamples were analyzed to determine bulk chemistry and selected subsamples were analyzed for trace-element partitioning and (137)Cs activity. The purpose of these analyses was to determine the trace-element concentrations and distributions in the sediment column and to try to establish a trace-element geochemical history of the lake in relation to mining and mining-related discharge operations in the area. Substantial portions of the near-surface sediments in Lake Coeur d'Alene are markedly enriched in Ag, As, Cd, Hg, Pb, Sb, and Zn, and somewhat enriched in Cu, Fe, and Mn. Variations in the thickness of the trace element- rich sediments suggest that the source of much of this material is the Coeur d'Alene River. Calculated estimates indicate that there are some 75 million metric tons of trace element-rich sediments currently on/in the lakebed. Estimated trace-element masses in excess of those caused by non-mining-related sources, range from a high of 468,000 metric tons of Pb to a low of 260 metric tons of Hg. The similarity between the trace element-rich surface and subsurface sediments as regards their: (1) location; (2) bulk chemistry; (3) interelement relationships; and (4) trace-element partitioning indicate that the sources and/or concentrating mechanisms causing the trace-element enrichment in the lake probably have been the same throughout their depositional history. Based on Mt. St. Helens' ash layer from the 1980 eruption, ages estimated from (137)Cs activity, and the presence of 80 discernible and presumably annual layers in a core collected near the Coeur d'Alene River delta, it appears that deposition rates for the trace element-rich sediments varied from 2.1 to 1.3 cm/yr. These data also indicate that the deposition of trace element-rich sediments began, at least in the Coeur d'Alene River delta, sometime between 1895 and 1910, dates consistent with the onset of mining and ore-processing activities in the area which began in the 1880's.

Open-File Report↗

USGS2006

Environmental Setting of the Morgan Creek Basin, Maryland, 2002-04

The Morgan Creek Basin is a 31-square-kilometer watershed in Kent County, Maryland on the Delmarva Peninsula. The Delmarva Peninsula covers about 15,500 square kilometers and includes most of the State of Delaware and parts of Maryland and Virginia east of the Chesapeake Bay. The Morgan Creek Basin is one of five sites selected for the study of sources, transport, and fate by the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program's: Agricultural Chemicals: Sources, Transport and Fate study team (Agricultural Chemicals Team, ACT). A key component of the study is identifying the natural factors and human influences affecting water quality in the Morgan Creek Basin. The Morgan Creek Basin is in the Coastal Plain Physiographic Province, which is a nearly level seaward-sloping lowland with areas of moderate topographic relief. The study area lies within a well-drained upland region with permeable and porous soils and aquifer sediments. The soils are well suited to most field crops. Agriculture is the principal land use in the Morgan Creek Basin, as well as throughout the entire Delmarva Peninsula. Most agricultural land is used for row crops such as corn, soybeans, and small grains, and slightly less land is used for pasture and hay production involving alfalfa, clover, and various perennial grasses. There are several animal operations in the study area. Farm management practices include fertilizer and herbicide applications, different tillage practices, addition of lime, forested riparian buffers, grassed waterways, and sediment retention ponds. Irrigation in the study area is minimal. The climate of the Morgan Creek Basin is humid and subtropical, with an average annual precipitation of 1.12 meters. Overall annual precipitation is evenly distributed throughout the year, from 76 to 101 millimeters per month; however, the spring and summer (March - September) tend to be slightly wetter than the autumn and winter (October - February). Anomalously high precipitation can occur in summer/early autumn due to occasional hurricanes and tropical storms. Thunderstorms can also produce relatively high localized precipitation over the Morgan Creek Basin during the summer months. Mean daily streamflows for Morgan Creek are highly variable, and somewhat flashy due to the relatively small area of the basin. The long-term median base flow for Morgan Creek is 59 percent of total flow, indicating that total streamflow is most often dominated by a sustained ground-water contribution. Surface runoff accounts for the other 41 percent of the water in total streamflow and dominates during and just after precipitation events. The surficial aquifer in the study area consists of permeable quartz-rich sand and gravel and is underlain by less permeable marine sand, silt, and clay. The depth to water table ranges from less than 0.4 meters below land surface in the floodplain to 12 meters below land surface in upland areas. Ground water generally flows from uplands toward the Morgan Creek floodplain at a variety of depths and time scales. Because the soils and sediments are permeable and porous, some fraction of chemicals applied to the land surface tend to move downward to the water table where they are transported to discharge areas near Morgan Creek.

Open-File Report↗

USGS2010

Application of the Systems Impact Assessment Model (SIAM) to fishery resource issues in the Klamath River, California

At the request of two offices of the U.S. Fish and Wildlife Service (FWS) located in Yreka and Arcata, Calif., we applied the Systems Impact Assessment Model (SIAM) to analyze a variety of water management concerns associated with the Federal Energy Regulatory Commission (FERC) relicensing of the Klamath hydropower projects or with ongoing management of anadromous fish stocks in the mainstem Klamath River, Oregon and California. Requested SIAM analyses include predicted effects of reservoir withdrawal elevations, use of full active storage in Copco and Iron Gate Reservoirs to augment spring flows, and predicted spawning and juvenile outmigration timing of fall Chinook salmon. In an effort to further refine the analysis of spring flow effects on predicted fall Chinook production, additional SIAM analyses were performed for predicted response to spring flow release variability from Iron Gate Dam, high and low pulse flow releases, the predicted effects of operational constraints for both Upper Klamath Lake water surface elevations, and projected flow releases specified in the Klamath Project 2006 Operations Plan (April 10, 2006). Results of SIAM simulations to determine flow and water temperature relationships indicate that up to 4 degrees C of thermal variability can be attributed to flow variations, but the effect is seasonal. Much more of thermal variability can be attributed to air temperature variations, up to 6 degrees C. Reservoirs affect the annual thermal signature by delaying spring warming by about 3 weeks and fall cooling by about 2 weeks. Multi-level release outlets on Iron Gate Dam would have limited utility; however, if releases are small (700 cfs) and a near-surface and bottom-level outlet could be blended, then water temperature may be reduced by 2-4 degrees C for a 4-week period during September. Using the full active storage in Copco and Iron Gate Reservoir, although feasible, had undesirable ramifications such as earlier spring warming, loss of hydropower production, and inability to re-fill the reservoirs without causing shortages elsewhere in the system. Altering spawning and outmigration timing may be important management objectives for the salmon fishery, but difficult to implement. SIAM predicted benefits that might occur if water temperature was cooler in fall and spring emergence was advanced; however, model simulations were based on purely arbitrary thermal reductions. Spring flow variability did indicate that juvenile fall Chinook rearing habitat was the major biological 'bottleneck' for year class success. Rearing habitat is maximal in a range between 4,500 and 5,500 cfs below Iron Gate Dam. These flow levels are not typically provided by Klamath River system operations, except in very wet years. The incremental spring flow analysis provided insight into when and how long a pulse flow should occur to provide predicted fall Chinook salmon production increases. In general, March 15th - April 30th of any year was the period for pulse flows and 4000 cfs was the target flow release that provided near-optimal juvenile rearing habitat. Again, competition for water resources in the Klamath River Basin may make implementation of pulsed flows difficult.

California, Oregon↗

USGS1997

Characterization of stormwater runoff in Sioux Falls, South Dakota, 1995-96

The Kenai River in southcentral Alaska is an economically important salmon river generating as much as $78 million annually in direct benefits. Resource-management agencies are concerned that increased sedimentation and loss of streamside cover associated with accelerated erosion rates caused by boat activity may threaten salmon returns to the river. Bank loss and boat activity were characterized during 1996 along 67 miles of the Kenai River, including a segment of the river several miles long where boat activity is restricted to non-motorized uses. Bank loss in the non-motorized segment of the river was about 75 percent less than that observed in the highest boat-use area of the river and 33 per cent less than that observed in the lowest boat-use area of the river. Dates of peak boat activity coincided closely with chinook salmon returns to the Kenai River and with peaks in measured bank erosion. The boat activity period began in late May, peaked on weekend days in mid-July, and declined in early August. Observed boat traffic on the Kenai River included boats from 10 to 26 feet in length that transported 1 to 8 passengers. The most commonly observed boats were between 16 and 20 feet long and carried 4 or 5 passengers. The number of boats operated by commercial fishing guides represented 40 percent of the boats counted by the Alaska Department of Natural Resources, 55 percent of the boats counted by the Alaska Department of Fish and Game, and 57 percent of those recorded by observers during this study. The maximum boat activity and the maximum bank loss were measured at the RW's Campground study site about 16 river miles upstream from the mouth of the Kenai River. Between July 12 and September 10, 1996, more than 20,100 boats traveled by this site and the streambank along the inside of the meander bend was undercut to a depth of 45 inches at one measuring point. Boat activity and bank loss were greatest in areas of the river between about river miles 9 and 18 and river miles 39 and 46. These two segments of the river are popular residential and fishing areas and have banks composed of non-cohesive soils. In addition, a meandering, un-armored channel makes the banks along these two segments susceptible to erosion. The Kenai River in southcentral Alaska is an economically important salmon river generating as much as $78 million annually in direct benefits. Resource-management agencies are concerned that increased sedimentation and loss of streamside cover associated with accelerated erosion rates caused by boat activity may threaten salmon returns to the river. Bank loss and boat activity were characterized during 1996 along 67 miles of the Kenai River, including a segment of the river several miles long where boat activity is restricted to non-motorized uses. Bank loss in the non-motorized segment of the river was about 75 percent less than that observed in the highest boat-use area of the river and 33 percent less than that observed in the lowest boat-use area of the river. Dates of peak boat activity coincided closely with chinook salmon returns to the Kenai River and with peaks in measured bank erosion. The boat activity period began in late May, peaked on weekend days in mid-July, and declined in early August. Observed boat traffic on the Kenai River included boats from 10 to 26 feet in length that transported 1 to 8 passengers. The most commonly observed boats were between 16 and 20 feet long and carried 4 or 5 passengers. The number of boats operated by commercial fishing guides represented 40 percent of the boats counted by the Alaska Department of Natural Resources, 55 percent of the boats counted by the Alaska Department of Fish and Game, and 57 percent of those recorded by observers during this study. The maximum boat activity and the maximum bank loss were measured at the RW's Campground study site about 16 river miles upstream from the mouth of the Kenai River. Between July 12 and September 10, 1996, more than 20,10

Water-Resources Investigations Report↗

USGS2006

Factors Affecting Firm Yield and the Estimation of Firm Yield for Selected Streamflow-Dominated Drinking-Water-Supply Reservoirs in Massachusetts

Factors affecting reservoir firm yield, as determined by application of the Massachusetts Department of Environmental Protection's Firm Yield Estimator (FYE) model, were evaluated, modified, and tested on 46 streamflow-dominated reservoirs representing 15 Massachusetts drinking-water supplies. The model uses a mass-balance approach to determine the maximum average daily withdrawal rate that can be sustained during a period of record that includes the 1960s drought-of-record. The FYE methodology to estimate streamflow to the reservoir at an ungaged site was tested by simulating streamflow at two streamflow-gaging stations in Massachusetts and comparing the simulated streamflow to the observed streamflow. In general, the FYE-simulated flows agreed well with observed flows. There were substantial deviations from the measured values for extreme high and low flows. A sensitivity analysis determined that the model's streamflow estimates are most sensitive to input values for average annual precipitation, reservoir drainage area, and the soil-retention number-a term that describes the amount of precipitation retained by the soil in the basin. The FYE model currently provides the option of using a 1,000-year synthetic record constructed by randomly sampling 2-year blocks of concurrent streamflow and precipitation records 500 times; however, the synthetic record has the potential to generate records of precipitation and streamflow that do not reflect the worst historical drought in Massachusetts. For reservoirs that do not have periods of drawdown greater than 2 years, the bootstrap does not offer any additional information about the firm yield of a reservoir than the historical record does. For some reservoirs, the use of a synthetic record to determine firm yield resulted in as much as a 30-percent difference between firm-yield values from one simulation to the next. Furthermore, the assumption that the synthetic traces of streamflow are statistically equivalent to the historical record is not valid. For multiple-reservoir systems, the firm-yield estimate was dependent on the reservoir system's configuration. The firm yield of a system is sensitive to how the water is transferred from one reservoir to another, the capacity of the connection between the reservoirs, and how seasonal variations in demand are represented in the FYE model. Firm yields for 25 (14 single-reservoir systems and 11 multiple-reservoir systems) reservoir systems were determined by using the historical records of streamflow and precipitation. Current water-use data indicate that, on average, 20 of the 25 reservoir systems in the study were operating below their estimated firm yield; during months with peak demands, withdrawals exceeded the firm yield for 8 reservoir systems.

Scientific Investigations Report↗

USGS2013

Continuous real-time water-quality monitoring and regression analysis to compute constituent concentrations and loads in the North Fork Ninnescah River upstream from Cheney Reservoir, south-central Kansas, 1999–2012

Cheney Reservoir, located in south-central Kansas, is the primary water supply for the city of Wichita. The U.S. Geological Survey has operated a continuous real-time water-quality monitoring station since 1998 on the North Fork Ninnescah River, the main source of inflow to Cheney Reservoir. Continuously measured water-quality physical properties include streamflow, specific conductance, pH, water temperature, dissolved oxygen, and turbidity. Discrete water-quality samples were collected during 1999 through 2009 and analyzed for sediment, nutrients, bacteria, and other water-quality constituents. Regression models were developed to establish relations between discretely sampled constituent concentrations and continuously measured physical properties to compute concentrations of those constituents of interest that are not easily measured in real time because of limitations in sensor technology and fiscal constraints. Regression models were published in 2006 that were based on data collected during 1997 through 2003. This report updates those models using discrete and continuous data collected during January 1999 through December 2009. Models also were developed for four new constituents, including additional nutrient species and indicator bacteria. In addition, a conversion factor of 0.68 was established to convert the Yellow Springs Instruments (YSI) model 6026 turbidity sensor measurements to the newer YSI model 6136 sensor at the North Ninnescah River upstream from Cheney Reservoir site. Newly developed models and 14 years of hourly continuously measured data were used to calculate selected constituent concentrations and loads during January 1999 through December 2012. The water-quality information in this report is important to the city of Wichita because it allows the concentrations of many potential pollutants of interest to Cheney Reservoir, including nutrients and sediment, to be estimated in real time and characterized over conditions and time scales that would not be possible otherwise. In general, model forms and the amount of variance explained by the models was similar between the original and updated models. The amount of variance explained by the updated models changed by 10 percent or less relative to the original models. Total nitrogen, nitrate, organic nitrogen, E. coli bacteria, and total organic carbon models were newly developed for this report. Additional data collection over a wider range of hydrological conditions facilitated the development of these models. The nitrate model is particularly important because it allows for comparison to Cheney Reservoir Task Force goals. Mean hourly computed total suspended solids concentration during 1999 through 2012 was 54 milligrams per liter (mg/L). The total suspended solids load during 1999 through 2012 was 174,031 tons. On an average annual basis, the Cheney Reservoir Task Force runoff (550 mg/L) and long-term (100 mg/L) total suspended solids goals were never exceeded, but the base flow goal was exceeded every year during 1999 through 2012. Mean hourly computed nitrate concentration was 1.08 mg/L during 1999 through 2012. The total nitrate load during 1999 through 2012 was 1,361 tons. On an annual average basis, the Cheney Reservoir Task Force runoff (6.60 mg/L) nitrate goal was never exceeded, the long-term goal (1.20 mg/L) was exceeded only in 2012, and the base flow goal of 0.25 mg/L was exceeded every year. Mean nitrate concentrations that were higher during base flow, rather than during runoff conditions, suggest that groundwater sources are the main contributors of nitrate to the North Fork Ninnescah River above Cheney Reservoir. Mean hourly computed phosphorus concentration was 0.14 mg/L during 1999 through 2012. The total phosphorus load during 1999 through 2012 was 328 tons. On an average annual basis, the Cheney Reservoir Task Force runoff goal of 0.40 mg/L for total phosphorus was exceeded in 2002, the year with the largest yearly mean turbidity, and the long-term goal (0.10 mg/L) was exceeded in every year except 2011 and 2012, the years with the smallest mean streamflows. The total phosphorus base flow goal of 0.05 mg/L was exceeded every year. Given that base flow goals for total suspended solids, nitrate, and total phosphorus were exceeded every year despite hydrologic conditions, the established base flow goals are either unattainable or substantially more best management practices will need to be implemented to attain them. On an annual average basis, no discernible patterns were evident in total suspended sediment, nitrate, and total phosphorus concentrations or loads over time, in large part because of hydrologic variability. However, more rigorous statistical analyses are required to evaluate temporal trends. A more rigorous analysis of temporal trends will allow evaluation of watershed investments in best management practices.

Kansas↗

USGS2009

Emissions from coal fires and their impact on the environment

Self-ignited, naturally occurring coal fires and fires resulting from human activities persist for decades in underground coal mines, coal waste piles, and unmined coal beds. These uncontrolled coal fires occur in all coal-bearing parts of the world (Stracher, 2007) and pose multiple threats to the global environment because they emit greenhouse gases - carbon dioxide (CO 2 ), and methane (CH 4 ) - as well as mercury (Hg), carbon monoxide (CO), and other toxic substances (fig. 1). The contribution of coal fires to the global pool of atmospheric CO 2 is little known but potentially significant. For China, the world's largest coal producer, it is estimated that anywhere between 10 million and 200 million metric tons (Mt) of coal reserves (about 0.5 to 10 percent of production) is consumed annually by coal fires or made inaccessible owing to fires that hinder mining operations (Rosema and others, 1999; Voigt and others, 2004). At this proportion of production, coal amounts lost to coal fires worldwide would be two to three times that for China. Assuming this coal has mercury concentrations similar to those in U.S. coals, a preliminary estimate of annual Hg emissions from coal fires worldwide is comparable in magnitude to the 48 tons of annual Hg emissions from all U.S. coal-fired power-generating stations combined (U.S. Environmental Protection Agency, 2002). In the United States, the combined cost of coal-fire remediation projects, completed, budgeted, or projected by the U.S. Department of the Interior's Office of Surface Mining Reclamation and Enforcement (OSM), exceeds $1 billion, with about 90% of that in two States - Pennsylvania and West Virginia (Office of Surface Mining Enforcement and Reclamation, 2008; fig. 2). Altogether, 15 States have combined cumulative OSM coal-fire project costs exceeding $1 million, with the greatest overall expense occurring in States where underground coal fires are predominant over surface fires, reflecting the greater cost of extinguishing underground fires (fig. 2) (see 'Controlling Coal Fires'). In this fact sheet we review how coal fires occur, how they can be detected by airborne and remote surveys, and, most importantly, the impact coal-fire emissions may have on the environment and human health. In addition, we describe recent efforts by the U.S. Geological Survey (USGS) and collaborators to measure fluxes of CO 2 , CO, CH 4 , and Hg, using groundbased portable detectors, and combining these approaches with airborne thermal imaging and CO 2 measurements. The goal of this research is to develop approaches that can be extrapolated to large fires and to extrapolate results for individual fires in order to estimate the contribution of coal fires as a category of global emissions.

Fact Sheet↗

USGS2011

Crims Island-Restoration and monitoring of juvenile salmon rearing habitat in the Columbia River Estuary, Oregon, 2004-10

Under the 2004 Biological Opinion for operation of the Federal Columbia River Power System released by the National Marine Fisheries Service, the U.S. Army Corps of Engineers (USACE), the Bonneville Power Administration (BPA), and the Bureau of Reclamation (Reclamation) were directed to restore more than 4,047 hectares (10,000 acres) of tidal marsh in the Columbia River estuary by 2010. Restoration of Crims Island near Longview, Washington, restored 38.1 hectares of marsh and swamp in the tidal freshwater portion of the lower Columbia River. The goal of the restoration was to improve habitat for juveniles of Endangered Species Act (ESA)-listed salmon stocks and ESA-listed Columbian white-tailed deer. The U.S. Geological Survey (USGS) monitored and evaluated the fisheries and aquatic resources at Crims Island in 2004 prior to restoration (pre-restoration), which began in August 2004, and then post-restoration from 2006 to 2009. This report summarizes pre- and post-restoration monitoring data used by the USGS to evaluate project success. We evaluated project success by examining the interaction between juvenile salmon and a suite of broader ecological measures including sediments, plants, and invertebrates and their response to large-scale habitat alteration. The restoration action at Crims Island from August 2004 to September 2005 was to excavate a 0.6-meter layer of soil and dig channels in the interior of the island to remove reed canary grass and increase habitat area and tidal exchange. The excavation created 34.4 hectares of tidal emergent marsh where none previously existed and 3.7 hectares of intertidal and subtidal channels. Cattle that had grazed the island for more than 50 years were relocated. Soil excavated from the site was deposited in upland areas next to the tidal marsh to establish an upland forest. Excavation deepened and widened an existing T-shaped channel to increase tidal flow to the interior of the island. The western arm of the existing 'T-channel' was extended westward and connected to Bradbury Slough to create a second outlet to the main river. New intertidal channels were constructed from the existing 'T-channel' and tidal mudflats became inundated at high tide to increase rearing habitat for juvenile salmonids. The restoration action resulted in a 95-percent increase in available juvenile salmon rearing habitat. We collected juvenile salmon and other fishes at Crims Island and a nearby reference site using beach seines and fyke nets annually from March through August during all years. Benthic invertebrates were collected with sediment corers and drift invertebrates were collected with neuston nets. Juvenile salmon stomach contents were sampled using lavage. Vegetation and sediments characteristics were surveyed and we conducted a topographic/bathymetric survey using a RTK (real time kinematic) GPS (global positioning system). The fish assemblage at Crims Island, composed primarily of threespine stickleback (Gasterosteus aculeatus), non-native banded killifish (Fundulus diaphanus), peamouth chub (Mylocheilus caurinus), subyearling Chinook salmon (Oncorhynchus tshawytscha) (hereinafter referred to as subyearlings), and small numbers of juvenile chum salmon (Oncorhynchus keta), did not differ appreciably pre- and post-restoration. Subyearlings were the primary salmonid collected and were seasonally abundant from April through May during all years. The abundance of juvenile salmon declined seasonally as water temperature exceeded 20 degrees C in the Reference site by mid-June; however, subyearlings persisted at the Mainstem site and in subtidal channels of the Restoration site through the summer in water temperatures exceeding 22 degrees C. Residence times of subyearlings in Crims Island backwaters generally were short consisting of one or two tidal cycles. Median residence time was longer in the Restoration site than in the Reference site pre- and post-restoration. Small (mean = 55.7 millimeters) subyea

Scientific Investigations Report↗

USGS1976

Organic carbon and nitrogen concentrations and annual organic carbon load of six selected rivers of the United States

The organic carbon load during 1969-70 of each of the six rivers in this study is substantial. The 3.4-billion-kilogram (3.7-million-ton) and 47-million-kilogram (52-thousandton) annual organic carbon loads of the Mississippi River and the Brazos River (Tex.), respectively, were approximately equally distributed between dissolved and suspended phases, whereas the 725-million-kilogram (79.8-million-ton) organic load of the Missouri River was primarily in the suspended phase. The major portion of the 6.4-million-kilogram (7.3 thousand-ton) and the 19-million-kilogram (21-thousand-ton) organic carbon loads of the Sopchoppy River (Fla.) and the Neuse River (N.C.), respectively, was in the dissolved phase. DOC (dissolved organic carbon) concentrations in most rivers were usually less than 8 milligrams per litre. SOC (suspended organic carbon) concentrations fluctuated markedly with discharge, ranging between 1 and 14 percent, by weight, in sediment of most rivers. DOC concentrations were found to be independent of discharge, whereas SOC and SIC (suspended inorganic carbon) concentrations were positively correlated with discharge. Seasonal fluctuations in DOC and SOC were exhibited by the Missouri, Neuse, Ohio, and Brazos Rivers, but both SOC and DOC concentrations were relatively constant throughout the year in the Mississippi and Sopchoppy Rivers. The carbon-nitrogen ratio in the sediment phase of all river waters averaged less than 8 1 as compared with 12:1 or greater for most soils. This high nitrogen content shows a nitrogen enrichment of the stream sediment over that in adjacent soils, which suggests that different decomposition and humification processes are operating in streams than in the soils. The abundance of organic material in the dissolved and suspended phase of all river waters in this study indicate a large capacity factor for various types of organic reactivity within all streams and the quantitative importance of organic constituents in relation to the water quality of rivers and streams.

Water Supply Paper↗

USGS1966

Channel and hillslope processes in a semiarid area, New Mexico

Ephemeral washes having drainage areas from a few acres to 5 square miles are shown by actual measurement to be accumulating sediment on the streambed. This aggradation is not apparent to the eye but is clearly shown in 7 years of annual remeasurement. A similar aggradation was in progress in the same area some 3000 years ago as evidenced by an alluvial terrace later dissected by the present channel system. At that time as well as at present, aggradation occurred even in tributary areas draining a few acres. Colluvial accumulations merge with channel deposits and blanket the valleys and tributary basins even up to a few hundred feet of the drainage divides. The present study concerned the amounts of sediment produced by different erosion processes in various physiographic positions in the drainage basins. Measurements show that by far the largest sediment source is sheet erosion operating on the small percentage of basin area near the basin divides. Mass movement, gully head extension, and channel enlargement are presently small contributors of sediment compared with sheet erosion on unrilled slopes. As in previous studies, not all of the erosion products could be accounted for by accumulations on colluvial slopes and on beds of channels. The discrepancies are attributed primarily to sediment carried completely out of the basins studied and presumably deposited somewhere downstream. Aggradation of alluvial valleys of 5 square miles area and smaller both in the present epicycle, and in prehistorical but post-glacial times in this locality, cannot be attributed to gullying or rill extension in the headwater tributaries but to sheet erosion of the most upstream margins of the basins. Studies of rainfall characteristics of the 7 years of measurement compared with previous years in the 100-year record do not provide a clear-out difference which would account for the presently observed aggradation of channels. Longer period of measurement of erosion and sedimentation will be necessary to identify what precipitation parameters govern whether the channels aggrade or degrade.

Professional Paper↗

USGS2013

Equations for estimating bankfull channel geometry and discharge for streams in Massachusetts

Regression equations were developed for estimating bankfull geometry—width, mean depth, cross-sectional area—and discharge for streams in Massachusetts. The equations provide water-resource and conservation managers with methods for estimating bankfull characteristics at specific stream sites in Massachusetts. This information can be used for the adminstration of the Commonwealth of Massachusetts Rivers Protection Act of 1996, which establishes a protected riverfront area extending from the mean annual high-water line corresponding to the elevation of bankfull discharge along each side of a perennial stream. Additionally, information on bankfull channel geometry and discharge are important to Federal, State, and local government agencies and private organizations involved in stream assessment and restoration projects. Regression equations are based on data from stream surveys at 33 sites (32 streamgages and 1 crest-stage gage operated by the U.S. Geological Survey) in and near Massachusetts. Drainage areas of the 33 sites ranged from 0.60 to 329 square miles (mi2). At 27 of the 33 sites, field data were collected and analyses were done to determine bankfull channel geometry and discharge as part of the present study. For 6 of the 33 sites, data on bankfull channel geometry and discharge were compiled from other studies done by the U.S. Geological Survey, Natural Resources Conservation Service of the U.S. Department of Agriculture, and the Vermont Department of Environmental Conservation. Similar techniques were used for field data collection and analysis for bankfull channel geometry and discharge at all 33 sites. Recurrence intervals of the bankfull discharge, which represent the frequency with which a stream fills its channel, averaged 1.53 years (median value 1.34 years) at the 33 sites. Simple regression equations were developed for bankfull width, mean depth, cross-sectional area, and discharge using drainage area, which is the most significant explanatory variable in estimating these bankfull characteristics. The use of drainage area as an explanatory variable is also the most commonly published method for estimating these bankfull characteristics. Regional curves (graphic plots) of bankfull channel geometry and discharge by drainage area are presented. The regional curves are based on the simple regression equations and can be used to estimate bankfull characteristics from drainage area. Multiple regression analysis, which includes basin characteristics in addition to drainage area, also was used to develop equations. Variability in bankfull width, mean depth, cross-sectional area, and discharge was more fully explained by the multiple regression equations that include mean-basin slope and drainage area than was explained by equations based on drainage area alone. The Massachusetts regional curves and equations developed in this study are similar, in terms of values of slopes and intercepts, to those developed for other parts of the northeastern United States. Limitations associated with site selection and development of the equations resulted in some constraints for the application of equations and regional curves presented in this report. The curves and equations are applicable to stream sites that have (1) less than about 25 percent of their drainage basin area occupied by urban land use (commercial, industrial, transportation, and high-density residential), (2) little to no streamflow regulation, especially from flood-control structures, (3) drainage basin areas greater than 0.60 mi2 and less than 329 mi2, and (4) a mean basin slope greater than 2.2 percent and less than 23.9 percent. The equations may not be applicable where streams flow through extensive wetlands. The equations also may not apply in areas of Cape Cod and the Islands and the area of southeastern Massachusetts close to Cape Cod with extensive areas of coarse-grained glacial deposits where none of the study sites are located. Regardless of the setting, the regression equations are not intended for use as the sole method of estimating bankfull characteristics; however, they may supplement field identification of the bankfull channel when used in conjunction with field verified bankfull indicators, flood-frequency analysis, or other supporting evidence.

Massachusetts↗

USGS2013

Hydrologic drought of water year 2011 compared to four major drought periods of the 20th century in Oklahoma

Water year 2011 (October 1, 2010, through September 30, 2011) was a year of hydrologic drought (based on streamflow) in Oklahoma and the second-driest year to date (based on precipitation) since 1925. Drought conditions worsened substantially in the summer, with the highest monthly average temperature record for all States being broken by Oklahoma in July (89.1 degrees Fahrenheit), June being the second hottest and August being the hottest on record for those months for the State since 1895. Drought conditions continued into the fall, with all of the State continuing to be in severe to exceptional drought through the end of September. In addition to effects on streamflow and reservoirs, the 2011 drought increased damage from wildfires, led to declarations of states of emergency, water-use restrictions, and outdoor burning bans; caused at least $2 billion of losses in the agricultural sector and higher prices for food and other agricultural products; caused losses of tourism and wildlife; reduced hydropower generation; and lowered groundwater levels in State aquifers. The U.S. Geological Survey, in cooperation with the Oklahoma Water Resources Board, conducted an investigation to compare the severity of the 2011 drought with four previous major hydrologic drought periods during the 20th century – water years 1929–41, 1952–56, 1961–72, and 1976–81. The period of water years 1925–2011 was selected as the period of record because few continuous record streamflow-gaging stations existed before 1925, and gaps in time existed where no streamflow-gaging stations were operated before 1925. In water year 2011, statewide annual precipitation was the 2d lowest, statewide annual streamflow was 16th lowest, and statewide annual runoff was 42d lowest of those 87 years of record. Annual area-averaged precipitation totals by the nine National Weather Service climate divisions from water year 2011 were compared to those during four previous major hydrologic drought periods to show how precipitation deficits in Oklahoma varied by region. The nine climate divisions in Oklahoma had precipitation in water year 2011 ranging from 43 to 76 percent of normal annual precipitation, with the Northeast Climate Division having the closest to normal precipitation and the Southwest Climate Division having the greatest percentage of annual deficit. Based on precipitation amounts, water year 2011 ranked as the second driest of the 1925–2011 period, being exceeded only in one year of the 1952 to 1956 drought period. Regional streamflow patterns for water year 2011 indicate that streamflow in the Arkansas-White-Red water resources region, which includes all of Oklahoma, was relatively large, being only the 26th lowest since 1930, primarily because of normal or above-normal streamflow in the northern part of the region. Twelve long-term streamflow-gaging stations with periods of record ranging from 67 to 83 years were selected to show how streamflow deficits varied by region in Oklahoma. Statewide, streamflow in water year 2011 was greater than streamflows measured in years during the drought periods of 1929–41, 1952–56, 1961–72, and 1976–81. The hydrologic drought worsened going from the northeast toward the southwest in Oklahoma, ranging from 140 percent (above normal streamflow) in the northeast, to 13 percent of normal streamflow in southwestern Oklahoma. The relatively low streamflow in 2011 resulted in 83.3 percent of the statewide conservation storage being available at the end of the water year in major reservoirs, similar to conservation storage in the preceding severe drought year of 2006. The ranking of streamflow as the 16th smallest for the 1925–2011 period, despite precipitation being ranked the 2d smallest, may have been caused, in part, by the relatively large streamflow in northeastern Oklahoma during water year 2011.

Oklahoma↗

USGS2003

Effectiveness of the New Hampshire stream-gaging network in providing regional streamflow information

The stream-gaging network in New Hampshire was analyzed for its effectiveness in providing regional information on peak-flood flow, mean-flow, and low-flow frequency. The data available for analysis were from stream-gaging stations in New Hampshire and selected stations in adjacent States. The principles of generalized-least-squares regression analysis were applied to develop regional regression equations that relate streamflow-frequency characteristics to watershed characteristics. Regression equations were developed for (1) the instantaneous peak flow with a 100-year recurrence interval, (2) the mean-annual flow, and (3) the 7-day, 10-year low flow. Active and discontinued stream-gaging stations with 10 or more years of flow data were used to develop the regression equations. Each stream-gaging station in the network was evaluated and ranked on the basis of how much the data from that station contributed to the cost-weighted sampling-error component of the regression equation. The potential effect of data from proposed and new stream-gaging stations on the sampling error also was evaluated. The stream-gaging network was evaluated for conditions in water year 2000 and for estimated conditions under various network strategies if an additional 5 years and 20 years of streamflow data were collected. The effectiveness of the stream-gaging network in providing regional streamflow information could be improved for all three flow characteristics with the collection of additional flow data, both temporally and spatially. With additional years of data collection, the greatest reduction in the average sampling error of the regional regression equations was found for the peak- and low-flow characteristics. In general, additional data collection at stream-gaging stations with unregulated flow, relatively short-term record (less than 20 years), and drainage areas smaller than 45 square miles contributed the largest cost-weighted reduction to the average sampling error of the regional estimating equations. The results of the network analyses can be used to prioritize the continued operation of active stations, the reactivation of discontinued stations, or the activation of new stations to maximize the regional information content provided by the stream-gaging network. Final decisions regarding altering the New Hampshire stream-gaging network would require the consideration of the many uses of the streamflow data serving local, State, and Federal interests.

Water-Resources Investigations Report↗

USGS2013

Changing patterns in the use, recycling, and material substitution of mercury in the United States

Environmental concerns have led to numerous regulations that have dramatically decreased the reported production and use of mercury in the United States since the 1980s. Government legislation and subsequent industry actions have led to increased collection of mercury-containing materials and the recovery of mercury through recycling. Mercury emissions have been reduced and effective alternatives to mercury products have been developed for many applications. This study updates and quantifies the changes in demand, supply, use, and material flow for mercury in various sectors in the United States that have taken place since 1996. Nearly all primary mercury produced in the United States is derived as a byproduct of processing of gold and silver ore in Nevada. Since 2001, annual production of mercury from gold and silver mining in Nevada has decreased by 22 percent overall because ore from greater depths containing low grade mercury is recovered, and mercury emissions from this source have decreased by 95 percent as a result of increased regulation and improved collection and suppression technology. The distribution of consumption of mercury in the United States has changed as a result of regulation (elimination of large-scale mercury use in the paint and battery sectors), reduction by consumers (decommissioning of mercury-cell chloralkali manufacturing capacity), and technological advances (improvements in dental, lighting, and wiring sectors). Mercury use in the chloralkali sector, the leading end-use sector in the United States in 1996, has declined by 98 percent from 136 metric tons (t) in 1996 to about 0.3 t in 2010 because of increased processing and recycling efficiencies and plant closures or conversion to other technologies. As plants were closed, mercury recovered from the infrastructure of decommissioned plants has been exported, making the United States a net exporter of mercury, even though no mercury has been produced as the primary product from mines in the United States since 1992. In 1996, the three leading end-use sectors for mercury in the United States were chloralkali manufacturing (accounting for 38 percent of consumption), electrical and electronic instrumentation (13 percent of consumption), and instruments and measuring devices (11 percent of consumption). In 2010, the three leading end-use sectors were dental amalgam (accounting for between 35 and 57 percent of consumption), electrical and electronic instrumentation (29 percent of consumption), and batteries (8 percent of consumption). Mercury use in lighting is increasing because incandescent lights are being phased out in favor of mercury-containing compact fluorescent bulbs, but the demand for mercury per unit produced is small. Dental amalgam constituted the largest amount of mercury in use in the United States. One study reported about 290 t of mercury in dental amalgam was estimated to be contained in human mouths, an estimated 30 t of mercury amalgam was treated as waste, 28.5 t of mercury amalgam was released to the environment, 6 t of amalgam was recycled, and 3.5 t was treated and stored in landfills in 2009. Mercury contained in products recovered by State, municipal, or industry collection activities is recycled, but the estimated overall recycling rate is less than 10 percent. Increasingly, the U.S. mercury recycling industry has been processing a significant amount of mercury-containing material derived from foreign gold mining operations or decommissioned mercury-cell chloralkali plants. Regulation of mercury export and storage is expected to result in surplus mercury inventories in the United States. The Mercury Export Ban Act of 2008 limits elemental mercury exports for unregulated uses such as artisanal gold mining after January 1, 2013, and requires development of adequate long-term storage facilities in the United States for elemental mercury. During the past 4 years, producers and recyclers of elemental mercury have been exporting large quantities of mercury in anticipation of this regulation, but the U.S. inventory of mercury in 2010 was estimated to have exceeded 7,000 t from Government stockpiles and industry stocks. Costs attributed to long-term storage may affect the competitiveness of mercury recycling.

Scientific Investigations Report↗

USGS2012

Evaluation of the effects of Middleton's stormwater-management activities on streamflow and water-quality characteristics of Pheasant Branch, Dane County, Wisconsin 1975-2008

Few long-term data sets are available for evaluating the effects of urban stormwater-management practices. Over 30 years of data are available for evaluating the effectiveness of such practices by the city of Middleton, Wis. Analysis of streamflow and water-quality data collected on Pheasant Branch, demonstrates the relation between the changes in the watershed to the structural and nonstructural best management practices put in place during 1975-2008. A comparison of the data from Pheasant Branch with streamflow and water-quality data (suspended sediment and total phosphorus) collected at other nearby streams was made to assist in the determination of the possible causes of the changes in Pheasant Branch. Based on 34 years of streamflow data collected at the Pheasant Branch at Middleton streamflow-gaging station, flood peak discharges increased 37 percent for the 2-year flood and 83 percent for the 100-year flood. A comparison of data for the same period from an adjacent rural stream, Black Earth at Black Earth had a 43 percent increase in the 2-year flood peak discharge and a 140-percent increase in the 100-year flood peak discharge. Because the flood peak discharges on Pheasant Branch have not increased as much as Black Earth Creek it appears that the stormwater management practices have been successful in mitigating the effects of urbanization. Generally urbanization results in increased flood peak discharges. The overall increase in flood peak discharges seen in both streams probably is the result of the substantial increase in precipitation during the study period. Average annual runoff in Pheasant Branch has also been increasing due to increasing average annual precipitation and urbanization. The stormwater-management practices in Middleton have been successful in decreasing the suspended-sediment and total phosphorus loads to Lake Mendota from the Pheasant Branch watershed. These loads decreased in spite of increased annual runoff and flood peaks, which are often expected to produce higher sediment and phosphorus loads. The biggest decreases in sediment and phosphorus loads occurred after 2001 when a large detention pond, the Confluence Pond, began operation. Since 2001, the annual suspended-sediment load has decreased from 2,650 tons per year to 1,450 tons per year for a 45-percent decrease. The annual total phosphorus load has decreased from 12,200 pounds per year to 6,300 pounds per year for a 48-percent decrease. A comparison of Pheasant Branch at Middleton with two other streams, Spring Harbor Storm Sewer and Yahara River at Windsor, that drain into Lake Mendota shows that suspended-sediment and total phosphorus load decreases were greatest at Pheasant Branch at Middleton. Prior to the construction of the Confluence Pond, annual suspended-sediment yield and total phosphorus yield from Pheasant Branch watershed was the largest of the three watersheds. After 2001, suspended-sediment yield was greatest at Spring Harbor Storm Sewer, and lowest at Yahara at Windsor; annual total phosphorus yield was greater at Yahara River at Windsor than that of Pheasant Branch. The stormwater-quality plan for Middleton shows that the city has met the present State of Wisconsin Administrative Code chap. NR216/NR151 requirements of reducing total suspended solids by 20 percent for the developed area in Middleton. In addition, the city already has met the 40-percent reduction in total suspended solids required by 2013. Snow and ice melt runoff from road surfaces and parking lots following winter storms can effect water quality because the runoff contains varying amounts of road salt. To evaluate the effect of road deicing on stream water quality in Pheasant Branch, specific conductance and chloride were monitored during two winter seasons. The maximum estimated concentration of chloride during the monitoring period was 931 milligrams per liter, which exceeded the U.S. Environmental Protection Agency acute criterion of 860 milligrams per liter. Chloride concentrations exceeded the U.S. Environmental Protection Agency chronic criterion of 230 milligrams per liter for at least 10 days during February and March 2007 and for 45 days during the 2007-8 winter seasons. The total sodium chloride load for the monitoring period was 1,720 tons and the largest sodium chloride load occurred in March and April of each year.

Wisconsin↗

USGS1995

Precipitation depth-duration and frequency characteristics for Antelope Valley, Mojave Desert, California

Methods to evaluate changes in the volume of storm runoff from drainage basins that are likely to be urbanized are needed by land-use planning agencies to establish criteria for the design of flood-control systems. To document the changes in runoff volume of basins that may be urbanized, nine small basins that are considered representative of varying hydrologic conditions in Antelope Valley, California, were selected for detailed study. Precipitation and stream-gaging stations were established and data were collected for the period 1990-93. The data collected at these U.S. Geological Survey stations were supplemented by data collected at 35 Long-term precipitation stations operated by the National Oceanic and Atmospheric Administration and the Los Angeles County Department of Public Works. These data will be used to calibrate and verify rainfall-runoff models for the nine basins. Results of the model runs will then be used as a guide for estimating basin runoff characteristics throughout Antelope Valley. Annual precipitation in Antelope Valley ranges from more than 20 inches in the mountains to less than 4 inches on the valley floor. Most precipitation in the valley falls during the months of December through March, but cyclonic storms in the fall and convectional storms in the summer sometimes occur. The duration of most storms ranges from 1 to 8 days, but most of the precipitation usually occurs within the first 2 days. Many parts of the valley have been affected by storms with precipitation depths that equal or exceed 0.60 inch per hour. The storms of January 1943 and March 1983 were the most intense storms of record, with recurrence intervals greater than 100 years in some parts of the valley. Depth-duration ratios were calculated by disaggregating daily total precipitation data for intervals of 1, 2, 3, 4, 6, 12, and 18 hours for storms that occurred during 1990-93. The hourly total precipitation data were then disaggregated at 5-minute intervals. A comparison of the depth-duration data collected during 1990-93 at the Geological Survey stations with the data collected at the other stations indicated that the 1990-93 data are not representative of historical storms. Therefore, depth-duration ratios developed using these data should be considered preliminary for use in disaggregating the historical hourly data for Antelope Valley. Annual maximum 24-hour precipitation records were used to calculate precipitation depth-frequency relations for 23 stations in the valley using the log Pearson type III distribution. These calculations indicate that the storms of January 1943 and March 1983 were the most intense of record in the valley with recurrence intervals greater than 100 years.

Water-Resources Investigations Report↗

USGS2014

Hydrographic survey of Chaktomuk, the confluence of the Mekong, Tonlé Sap, and Bassac Rivers near Phnom Penh, Cambodia, 2012

The U.S. Geological Survey, in cooperation with the U.S. Department of State, Mekong River Commission, Phnom Penh Autonomous Port, and the Cambodian Ministry of Water Resources and Meteorology, completed a hydrographic survey of Chaktomuk, which is the confluence of the Mekong, Tonlé Sap (also spelled Tônlé Sab), and Bassac Rivers near Phnom Penh, Cambodia. The hydrographic survey used a high-resolution multibeam echosounder mapping system to map the riverbed during April 21–May 2, 2012. The multibeam echosounder mapping system was made up of several components: A RESON Seabat™ 7125 multibeam echosounder, an inertial measurement unit and navigation unit, data collection computers, and a Real-Time Kinematic (RTK) Global Navigation Satellite System (GNSS) base station. The survey area was divided into six survey subreaches and each subreach was surveyed within 3 days along survey lines oriented parallel to the flow direction. Complete coverage of the riverbed was the operational objective; however, to obtain broad spatial coverage, gaps between parallel swaths were permitted, especially in wide, shallow areas where multibeam swath widths were narrow. The survey was referenced to two existing bench marks with known geographic coordinates by establishing a GNSS base station on the bench marks each day and using real-time corrections from the base station to correct boat navigation data. The World Geodetic System of 1984 (WGS 84) ellipsoid was used during data collection to reference height, and data were adjusted to the local datum, Ha Tien 1960, during postprocessing. The quality of hydrographic surveys was described by an uncertainty estimate called total propagated uncertainty (TPU). Calculations of TPU were completed for the hydrographic survey data resulting in the maximum TPU of 0.33 meters. The mean and median TPUs were 0.18 meters, and 99.9 percent of TPU values were less than 0.25 meters. Detailed hydrographic maps of Mekong, Tonlé Sap, and Bassac Rivers showing the riverbed elevations surveyed April 21–May 2, 2012, referenced to Ha Tien 1960 were produced. The surveyed area included a 2-km stretch of the Mekong River between the confluence with the Tonlé Sap and Bassac Rivers, and extended 4 km upstream and 3.6 km downstream from the 2,000-m confluence stretch of the Mekong River. In addition, 0.7 km of the Bassac River downstream and 3.5 km of the Tonlé Sap River (from the confluence to Chroy Changvar Bridge) upstream from their confluence with the Mekong River were surveyed. Riverbed features (such as dunes, shoals, and the effects of sediment mining, which were observed during data collection) are visible on the hydrographic maps. All surveys were completed at low annual water levels as referenced to nearby Mekong River Commission streamflow-gaging stations. Riverbed elevations surveyed ranged from 24.08 m below to 1.54 m above Ha Tien 1960.

Phnom Penh↗

USGS2000

The lasting effects of tank maneuvers on desert soils and intershrub flora

Mojave Desert soils and intershrub flora sustained lasting disturbances during military training maneuvers initiated by General George Patton, Jr. in the 1940s, and during Operation Desert Strike in 1964. At six sites, mean desert pavement clast size was significantly smaller by 15% to 50% in single tank tracks compared to undisturbed surfaces. The finer-grained tracks yielded significantly higher surface reflectance values at two of three sites. At one site, Patton era tank tracks cross centuries-old "intaglios" and there was no significant difference in clast size between the disturbances. Full recovery of pavement surfaces may require a change in climate since pavements formed in Pleistocene times under climatic conditions that no longer exist. Tank tracks of both ages exhibited significant levels of soil compaction, as indicated by penetrometer resistance values that were 51% to 120% greater than those in undisturbed soils to 0.3 m depth. Soil bulk density in tracks was 4% to 6% higher than in undisturbed soils. Soil compaction lowered infiltration rates in tank tracks by 24% to 55% in comparison to undisturbed soils. Compaction has prevented the intershrub flora from recovering in tank tracks. Annual and herbaceous perennial plant density was higher by 13% to 56% in tank tracks than in undisturbed soils, but compaction has restricted the growth of individual plants. This was reflected in plant cover values, which were 3% to 16% lower in tank tracks than in undisturbed soils. Soil compaction also altered the species composition. Species with long taproots, such as Chaenactis fremontii, were reduced in density and cover in tank tracks, whereas grass species with shallow, fibrous root systems had large density increases in tracks. Another important element of the intershrub flora, cryptobiotic crust, exhibited a low rate of recovery from the impact of tank travel at one site. The cover of the most well-developed component of the crusts, growing on delicate soil pedicels in undisturbed soils, was reduced by 50% in tank tracks because of destruction and compaction of the uppermost soil layers.

Arizona;California;Nevada↗