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USGS2006

Effects of roads and well pads on erosion in the Largo Canyon watershed, New Mexico, 2001-02

Largo Canyon, located in the San Juan Basin of northwestern New Mexico, is one of the longest dry washes in the world. Oil and gas production in the San Juan Basin, which began in the 1940's, required the development of an extensive network of dirt roads to service the oil and gas wells in the Navajo Reservoir area. Presently, there are about eight wells per square mile, and the density of oil and gas wells is expected to increase. Potential environmental effects on landscape stability that may result from the additional roads and well pads have not been documented. In 2001, the U.S. Geological Survey began a study in cooperation with the Bureau of Land Management to evaluate the effects of roads and well pads associated with oil and gas operations on the erosion potential of Bureau of Land Management lands in the Largo Canyon watershed. The effects of roads and well pads on erosion were quantified by installing sediment dams (dams) and by surveying transects across roads and well pads. Data from 26 dams were used in the analysis. Dams were installed at 43 sites: 21 on hillsides upslope from roads or pads to measure erosion from hillslopes, 11 at the downslope edges of roads to measure erosion from roads, and 11 at the downslope edges of well pads to measure erosion from well pads. Pairs of survey transects were established at nine well pads and two road locations. Sediment-accumulation data for 26 dams, recorded at 17 measurement intervals, indicate that average erosion rates at the dams significantly correlate to size of the contributing area. The average erosion rate normalized by drainage area was 0.001 foot per year below roads, 0.003 foot per year on hillslopes, and 0.011 foot per year below well pads. Results of a two-sample t-test indicate that there was no significant difference in average erosion rates for dams located on hillslopes and below roads, whereas average erosion rates were significantly greater for dams below well pads than for dams on hillslopes and dams below roads. The average erosion rates estimated from the data collected during this study most likely represent minimum erosion rates. Sediment-accumulation data for measurement intervals and for dams that were breached during 2002, resulting from the large volume of runoff generated by high-intensity storms, were not used to compute erosion rates. For this reason, the higher range of erosion rates is underrepresented and the results of this study are biased toward the lower end of the range of erosion rates. Measurements along road transects generally indicate that sediment is eroded from the top of road berms and redeposited at the base of the berms and may be transported downslope along the road. Measurements along well-pad transects generally indicate that sediment eroded from hillslopes is transported over the surface of the well pad and down the well-pad edges. Based on field observations, roads aligned parallel to topographic contours facilitate erosional processes in two ways: (1) roads cut across and collect runoff from previously established drainages and (2) roads, where they are cut into hillsides or into the land surface, provide focal points for the initiation of erosion. Roads aligned across topographic contours can serve as conduits to channel runoff but do not constitute a large percentage of the road network.

Scientific Investigations Report↗

USGS2022

The gap between experts, farmers and non-farmers on perceived environmental vulnerability and the influence of values and beliefs

Science has played a mixed role in guiding conservation and sustainability-oriented decision-making by individuals, policymakers, institutions, and governments. Not all science-based conservation and sustainability initiatives that address issues facing humanity and ecosystems and global problems have gained public support. Conservation decisions and policy prescriptions are and may be based on perceptions about and experiences with the environment, local land use, and ecosystems that may not align with or be grounded in science or evidence from experts in the field. Values, beliefs, and perceptions associated with nature play a critical role in how individuals view biodiversity conservation, sustainability, and natural resource management . This study first examines the gap between experts (scientists and other field experts) and the public (farmers and non-farmers) about the state of water and land resources, wildlife and associated habitats, and aquatic biodiversity in the Smoky Hill River Watershed in western Kansas. Second, the study examines the role that values and beliefs play in shaping environmental perceptions for farmers and non-farmers. Analysis confirms that a gap between experts and farmers/non-farmers does exist, especially with respect to the state of the Ogallala Aquifer, playas, rivers and streams, lakes and reservoirs, native grasslands, wildlife habitats, farmland, native fish populations, and wildlife species. Ordered-logistic regression analyses, meanwhile, indicate that farmer and non-farmer perceptions about the state of the local environment are influenced by traditional and self-interested values, as well as environmental values and beliefs, but less so by religiosity and political ideology. Despite broad takeaways, results exhibited heterogeneity across the farmer and non-farmer subpopulations. If environmental professionals cannot align ecological data, stakeholders’ values/perceptions, and policies, then the existing body of technical research and management on sustainability in natural and social sciences may be of little value.

Journal of Environmental Management↗

USGS2019

Integrated hydrologic modeling of the Salinas River, California, for sustainable water management

The Salinas River is the largest river in California’s Central Coast region. Groundwater resources of the Salinas River basin are used to meet water supply needs, including crop irrigation and municipal water supply. Two large multipurpose reservoirs also supply irrigation and municipal water uses. Historical imbalances between supply and demand have resulted in sinking groundwater levels, seawater intrusion, regulatory actions on pumping, adjudication, and requirements for minimum in-stream fish flows. Present needs include finding replacement water supplies and improving watershed management to comply with legal mandates, adapt to future climate variability and landuse conversions, and improve environmental conditions. The Salinas Valley Integrated Hydrologic Model (SVIHM) was developed to help water managers evaluate and adjust to projected impacts on water supplies and demands in the Salinas Valley watershed caused by changes in land use, population, and climate. The SVIHM includes four modeling components: (1) the Basin Characterization Model (BCM), (2) the Hydrologic Simulation Program – FORTRAN (HSPF), (3) MODFLOW - One Water Hydrologic Model (MF-OWHM), and (4) the Surface Water Operations (SWO) package. The BCM and HSPF components compose the Salinas Valley Watershed Model (SVWM). The 4,530 square-mile (mi2) SVWM domain encompasses the entire Salinas River watershed, as well as coastal drainages adjacent to the Salinas River outflow, and includes two separate and connected HSPF model domains, the 2,540 mi2 upper Salinas River and the 1,990 mi2 lower Salinas River models. SVWM (1) simulates the water budget for the entire Salinas River basin containing both the SVIHM domain as well as the mountainous terrain of the tributary headwater areas not included in the SVIHM; and (2) was used to develop the 148 boundary inflows for the SVIHM. Simulated evapotranspiration (ET) is the largest component of the water budget after precipitation, with a 71-year average basin-wide ET of 13.9 in/yr, compared to the basin-wide average precipitation of 18.4 in/yr. Simulated ET ranges from 15 to 29 in/yr along the western side of the SVWM to less than 10 in/yr throughout the valley floor and in the southeast part of the Salinas River watershed. The simulated total 71-year average inflow to the SVIHM was 890 ft3/sec (about 640,000 acre-feet per year), with the highest average inflow of 270 ft3/sec simulated for the Nacimiento River; whereas, the simulated 71-year average streamflow at the mouth of the Salinas River was only about 190 ft3/sec, indicating that most of the streamflow generated in the Salinas River basin is lost to channel seepage. The lack of sustained baseflow causes streamflow to be highly sensitive to the temporal variability in precipitation, especially during the drier periods, and this increases the importance of developing adequate reservoir management, flow augmentation, and conjunctive water use scenarios for potential future drought periods and potentially increased temporal variability in precipitation.

California↗

USGS2004

Water Resources Data for Oregon, Water Year 2003

The annual Oregon hydrologic data report is one of a series of annual reports that document hydrologic data gathered from the U.S. Geological Survey's surface- and ground-water data-collection networks in each State, Puerto Rico, and the Trust Territories. These records of streamflow, ground-water levels, and quality of water provide the hydrologic information needed by State, local and Federal agencies, and the private sector for developing and managing our Nation's land and water resources. This report includes records on both surface and ground water in Oregon and contains discharge records for 199 stream-gaging stations, 25 partial-record or miscellaneous streamflow stations, and 8 crest-stage partial-record streamflow stations; stage-only records for 6 gaging stations; stage and content records for 26 lakes and reservoirs; and water-quality records collected at 127 streamflow-gaging stations, 2 atmospheric deposition stations, and 11 ground-water sites.

Water Data Report↗

USGS2005

Water resources data for Oregon, water year 2004

The annual Oregon water data report is one of a series of annual reports that document hydrologic data gathered from the U.S. Geological Survey's surface- and ground-water data-collection networks in each State, Puerto Rico, and the Trust Territories. These records of streamflow, ground-water levels, and quality of water provide the hydrologic information needed by State, local, Tribal, and Federal agencies and the private sector for developing and managing our Nation's land and water resources. This report contains water year 2004 data for both surface and ground water, including discharge records for 209 streamflow-gaging stations, 42 partial-record or miscellaneous streamflow stations, and 9 crest-stage partial-record streamflow stations; stage-only records for 6 gaging stations; stage and content records for 15 lakes and reservoirs; water-level records from 12 long-term observation wells; and water-quality records collected at 133 streamflow-gaging stations and 1 atmospheric deposition station.

Water Data Report↗

USGS2003

Water Resources Data for Oregon, Water Year 2002

The annual Oregon hydrologic data report is one of a series of annual reports that document hydrologic data gathered from the U.S. Geological Survey's surface- and ground-water data-collection networks in each State, Puerto Rico, and the Trust Territories. These records of streamflow, ground-water levels, and quality of water provide the hydrologic information needed by State, local and Federal agencies, and the private sector for developing and managing our Nation's land and water resources. This report includes records on both surface and ground water in the State and contains discharge records for 181 stream-gaging stations, 47 partial-record or miscellaneous streamflow stations, and 8 crest-stage partial-record streamflow stations; stage-only records for 6 gaging stations; stage and content records for 26 lakes and reservoirs; and water-quality records for 127 streamflow-gaging stations, 2 atmospheric deposition stations, and 11 ground-water sites.

Water Data Report↗

USGS2017

Dam removal: Listening in

Dam removal is widely used as an approach for river restoration in the United States. The increase in dam removals—particularly large dams—and associated dam-removal studies over the last few decades motivated a working group at the USGS John Wesley Powell Center for Analysis and Synthesis to review and synthesize available studies of dam removals and their findings. Based on dam removals thus far, some general conclusions have emerged: (1) physical responses are typically fast, with the rate of sediment erosion largely dependent on sediment characteristics and dam-removal strategy; (2) ecological responses to dam removal differ among the affected upstream, downstream, and reservoir reaches; (3) dam removal tends to quickly reestablish connectivity, restoring the movement of material and organisms between upstream and downstream river reaches; (4) geographic context, river history, and land use significantly influence river restoration trajectories and recovery potential because they control broader physical and ecological processes and conditions; and (5) quantitative modeling capability is improving, particularly for physical and broad-scale ecological effects, and gives managers information needed to understand and predict long-term effects of dam removal on riverine ecosystems. Although these studies collectively enhance our understanding of how riverine ecosystems respond to dam removal, knowledge gaps remain because most studies have been short (< 5 years) and do not adequately represent the diversity of dam types, watershed conditions, and dam-removal methods in the U.S.

Water Resources Research↗

USGS2022

Integrative monitoring strategy for marine and freshwater harmful algal blooms and toxins across the freshwater-to-marine continuum

Many coastal states throughout the USA have observed negative effects in marine and estuarine environments caused by cyanotoxins produced in inland waterbodies that were transported downstream or produced in the estuaries. Estuaries and other downstream receiving waters now face the dual risk of impacts from harmful algal blooms (HABs) that occur in the coastal ocean as well as those originating in inland watersheds. Despite this risk, most HAB monitoring efforts do not account for hydrological connections in their monitoring strategies and designs. Monitoring efforts in California have revealed the persistent detection of cyanotoxins across the freshwater-to-marine continuum. These studies underscore the importance of inland waters as conduits for the transfer of cyanotoxins to the marine environment and highlight the importance of approaches that can monitor across hydrologically connected waterbodies. A HAB monitoring strategy is presented for the freshwater-to-marine continuum to inform HAB management and mitigation efforts and address the physical and hydrologic challenges encountered when monitoring in these systems. Three main recommendations are presented based on published studies, new datasets, and existing monitoring programs. First, HAB monitoring would benefit from coordinated and cohesive efforts across hydrologically interconnected waterbodies and across organizational and political boundaries and jurisdictions. Second, a combination of sampling modalities would provide the most effective monitoring for HAB toxin dynamics and transport across hydrologically connected waterbodies, from headwater sources to downstream receiving waterbodies. Third, routine monitoring is needed for toxin mixtures at the land–sea interface including algal toxins of marine origins as well as cyanotoxins that are sourced from inland freshwater or produced in estuaries. Case studies from California are presented to illustrate the implementation of these recommendations, but these recommendations can also be applied to inland states or regions where the downstream receiving waterbody is a freshwater lake, reservoir, or river.

California, Oregon↗

USGS2012

Availability and distribution of low flow in Anahola Stream, Kauaʻi, Hawaiʻi

Anahola Stream is a perennial stream in northeast Kauaʻi, Hawaiʻi, that supports agricultural, domestic, and cultural uses within its drainage basin. Beginning in the late 19th century, Anahola streamflow was diverted by Makee Sugar Company at altitudes of 840 feet (upper intake) and 280 feet (lower intake) for irrigating sugarcane in the Keālia area. When sugarcane cultivation in the Keālia area ceased in 1988, part of the Makee Sugar Company’s surface-water collection system (Makee diversion system) in the Anahola drainage basin was abandoned. In an effort to better manage available surface-water resources, the State of Hawaiʻi Department of Hawaiian Home Lands is considering using the existing ditches in the Anahola Stream drainage basin to provide irrigation water for Native Hawaiian farmers in the area. To provide information needed for successful management of the surface-water resources, the U.S. Geological Survey investigated the availability and distribution of natural low flow in Anahola Stream and also collected low-flow data in Goldfish Stream, a stream that discharges into Kaneha Reservoir, which served as a major collection point for the Makee diversion system. Biological surveys of Anahola Stream were conducted as part of a study to determine the distribution of native and nonnative aquatic stream fauna. Results of the biological surveys indicated the presence of the following native aquatic species in Anahola Stream: ʻoʻopu ʻakupa (Sandwich Island sleeper) and ʻoʻopu naniha (Tear-drop goby) in the lower stream reaches surveyed; and ʻoʻopu nākea (Pacific river goby), ʻoʻopu nōpili (Stimpson’s goby), and ʻōpae kalaʻole (Mountain shrimp) in the middle and upper stream reaches surveyed. Nonnative aquatic species were found in all of the surveyed stream reaches along Anahola Stream. The availability and distribution of natural low flow were determined using a combination of discharge measurements made from February 2011 to May 2012 at low-flow partial-record and seepage-run stations established at locations of interest along study-area streams. Upstream of the upper intake, the estimated natural (undiverted) median flow in Anahola Stream is 2.7 million gallons per day, and the flow is expected to be greater than or equal to 0.97 million gallons per day 95 percent of the time. About 0.7 mile upstream of the lower intake and downstream from the confluence with Keaʻoʻopu Stream, the estimated natural (undiverted) median flow in Anahola Stream is 6.3 million gallons per day, and the flow is expected to be greater than or equal to 2.7 million gallons per day 95 percent of the time. In Goldfish Stream, about 0.4 mile upstream from the point of discharge into Kaneha Reservoir, the estimated natural median flow is 0.54 million gallons per day, and the flow is expected to be greater than or equal to 0.23 million gallons per day 95 percent of the time. The discharge estimates are representative of low-flow conditions in the study-area streams, and they are applicable to the base period (water years 1961–2011) over which they have been computed. The distribution of natural low flow in Anahola Stream was characterized through data collected during wet- and dry-season seepage runs. Seepage-run results show that Anahola Stream was generally a gaining stream under natural low-flow conditions. During the wet-season seepage run, Anahola Stream at the station located upstream of tributary Kaʻalula Stream had more than five times the flow that was measured upstream from the upper intake. The estimated total gain (including tributary inflow) in the 6.1-mile seepage-run reach was 6.97 million gallons per day; about 42 percent of that gain was groundwater discharge to the main channel of Anahola Stream. During the dry-season seepage run, about 34 percent of the estimated total gain of 3.93 million gallons per day in the same seepage-run reach was groundwater discharge to the main channel of Anahola Stream. A 15-percent seepage loss was estimated in a 0.3-mile reach downstream from the confluence of Anahola and Keaʻoʻopu Streams. The report summarizes scenarios that describe (1) surface-water availability under regulated conditions of Anahola Stream if the upper and lower intakes are restored in the future; and (2) amount of flow available for agricultural use at the upper intake under a variety of potential instream-flow standards that may be established by the State of Hawaiʻi for the protection of instream uses.

Hawai'i↗

USGS2016

Roost site selection by ring-billed and herring gulls

Gulls ( Larus spp.) commonly roost in large numbers on inland and coastal waters, yet there is little information on how or where gulls choose sites for roosting. Roost site selection can lead to water quality degradation or aviation hazards when roosts are formed on water supply reservoirs or are close to airports. Harassment programs are frequently initiated to move or relocate roosting gulls but often have mixed results because gulls are reluctant to leave or keep returning. As such, knowledge of gull roost site selection and roosting ecology has applied and ecological importance. We used satellite telemetry and an information-theoretic approach to model seasonal roost selection of ring-billed ( L. delawarensis ) and herring gulls ( L. argentatus ) in Massachusetts, USA. Our results indicated that ring-billed gulls preferred freshwater roosts and will use a variety of rivers, lakes, and reservoirs. Herring gulls regularly roosted on fresh water but used salt water roosts more often than ring-billed gulls and also roosted on a variety of land habitats. Roost modeling showed that herring and ring-billed gulls selected inland fresh water roosts based on size of the water body and proximity to their last daytime location; they selected the largest roost closest to where they ended the day. Management strategies to reduce or eliminate roosting gulls could identify and try to eliminate other habitat variables (e.g., close-by foraging sites) that are attracting gulls before attempting to relocate or redistribute (e.g., through hazing programs) roosting birds.

Massachusetts↗

USGS1982

Soil conservation and the reduction of erosion and sedimentation in the Coon Creek basin, Wisconsin

The Coon Creek basin, in the Driftless Area of Wisconsin, has been strikingly transformed by soil conservation measures since the 1930's. Comparison of sheet and rill erosion by use of the Universal Soil Loss Equation, shows 1975 erosion rates on upland fields to be about one-fourth those of 1934. Average annual sedimentation accumulation in small reservoirs declined from about 5,000 megagrams per square kilometer in 1936-45 to about 50 megagrams per square kilometer in 1962-75. Analysis of deposition in tributary valleys suggests that annual rates declined from about 3,700 megagrams per square kilometer in the 1930 's to about 35-70 megagrams per square kilometer in recent years. These reductions in erosion and sedimentation are due principally to improvements in land management and, to a lesser degree, to changes in land use. (USGS)

Professional Paper↗

USGS2024

Restoring Pacific Lamprey in the Umpqua River Basin of Oregon: A workshop summary

The Umpqua River Basin in southwestern Oregon (Figure 1) is part of the lands inhabited by the Cow Creek Band of Umpqua Tribe of Indians and an area of active co-management authority. This Basin supports a unique fish fauna, including important populations of Pacific salmon ( Oncorhynchus spp.) and steelhead ( O. mykiss ), and other native fishes that are endemic to the region (Mims et al. 2018). Among these species, the Pacific Lamprey ( Entosphenus tridentatus ) is one of the most unique, representing an ancient lineage of jawless fishes that long predates the evolution of any other species of fish in the basin (Clemens et al. 2017, 2021a). The Pacific Lamprey also represents an important cultural and food resource that features prominently in the indigenous practices of the Cow Creek Band of Umpqua Tribe of Indians. This report provides a select summary of topics related to the conservation of Pacific Lamprey in the Umpqua River Basin. Many of the topics addressed herein were discussed in a workshop co-hosted by the Cow Creek Band of Umpqua Tribe of Indians and the U.S. Geological Survey in April of 2022. This workshop was focused on threats to Pacific Lamprey in fresh waters of the basin. The workshop highlighted science conducted over the past 15 years by local managers and researchers to understand and address these threats and provide new information relevant to the conservation and restoration of Pacific Lamprey. Attendees included staff from the Coquille Indian Tribe, Yakama Nation, Columbia River Inter-Tribal Fish Commission, Partnership for Umpqua Rivers, Rogue River Watershed Council, Curry Watersheds Council, PacifiCorp, Trout Unlimited, Jackson Soil and Water Conservation District, Oregon Department of Fish and Wildlife, Bureau of Land Management, U.S. Fish and Wildlife Service, and U.S. Forest Service. This report provides an overview of this workshop and recent science and provides an overview of potential future efforts that could inform restoration of Pacific Lamprey. This summary is organized into four sections that relate to the main topics of the workshop: 1) The physical habitat template (stream flow, instream wood, sediment, and water temperature), 2) movement barriers and reservoirs, 3) biological invasions, and 4) climate adaptation. These do not represent an exhaustive list of topics related to conservation of Pacific Lamprey in the Umpqua Basin.

Oregon↗

USGS1979

Investigations by the U.S. Geological Survey of soil and moisture conservation on public domain lands, 1941-1964

The passage of the Taylor Grazing Act in 1934 marked the end of an era in the land policies in the United States in that disposal of the public lands by homesteading was terminated except under rigidly prescribed procedures, and the remaining public lands covering about 175 million acres in the western conterminous states were brought under regulatory authority for grazing use. In 1934 the lands were mostly in a severe state of deterioration as a result of overgrazing and drought. In addition to reducing numbers of livestock using the lands, successive programs of conservation practices were established of which the Soil and Moisture Conservation Program of the Department of the Interior is of particular interest here. The services of the Geological Survey, in an investigational and advisory capacity were enlisted in this program. The work of the Geological Survey has consisted of the collection of hydrologic data, investigations of range-water supplies to facilitate management and provide information for design of structures and land-treatment measures. Appraisal of the effects of treatment practices has also been an important activity. Conservation on the public domain involves mainly growing vegetation for forage and reducing erosion. The two elements are intimately related--accomplishment in one is usually reflected by an improvement in the other. Erosion is a serious problem on most of the public domain, but particularly in the Colorado River and Rio Grande basins where, despite low annual water yields, the public domain and similar lands on the Indian reservations contribute the major part of the sediment measured at the downstream gaging stations. In parts of the Missouri River basin also, erosion is obviously very active but the sediment yield contributed by the public domain cannot be as readily isolated. The reasons for the erosion are generally evident--the erodibility of the rock and soils and the sparsity of vegetation as a result of low precipitation, unfavorable soils, or past land use. How much is due to the land use is still controversial, resulting in many questions relative to planning corrective measures. The problem facing the early administrators of the Taylor Grazing Act to bring about proper use and conservation of the public domain was a difficult one because of the lack of records on actual grazing use in animal-unit months of the qualified allottees and the lack of data on treatment practices in an arid area. Reduction of grazing was imperative in some localities, but generally, it could not be brought about as rapidly as it should have been. Numbers of animal units in the grazing districts were reduced from about 3.6 million in 1941 to about 3.2 million in 1964, whereas the areas included in districts was increased about 3 percent. Reductions are still being made in certain areas where deterioration is evident. One of the earliest activities connected with management of the range was the development of water supplies to facilitate the distribution of grazing. The investigations needed for such development formed a large part of the early work in the Soil and Moisture program of the Geological Survey and has continued to be a major activity to the present time. Most of the work has involved investigations of sites for wells but has included also the investigation of proposed spring developments and collection of hydrologic data for use in reservoir design. Well-site investigations have been of two general types: (1) the investigation of a site selected by the land administration agency, and (2) an areal investigation covering entire grazing districts or units thereof. In each type of investigation, a study is made of the geology and the recharge conditions. Reports are prepared giving estimates of the depth of drilling required, the depth to water, the yield, and the quality of the water, together with other information on drilling conditions and developing. Springs are a significant so

Open-File Report↗

USGS2013

Sediment transport in the San Francisco Bay Coastal System: An overview

The papers in this special issue feature state-of-the-art approaches to understanding the physical processes related to sediment transport and geomorphology of complex coastal-estuarine systems. Here we focus on the San Francisco Bay Coastal System, extending from the lower San Joaquin-Sacramento Delta, through the Bay, and along the adjacent outer Pacific Coast. San Francisco Bay is an urbanized estuary that is impacted by numerous anthropogenic activities common to many large estuaries, including a mining legacy, channel dredging, aggregate mining, reservoirs, freshwater diversion, watershed modifications, urban run-off, ship traffic, exotic species introductions, land reclamation, and wetland restoration. The Golden Gate strait is the sole inlet connecting the Bay to the Pacific Ocean, and serves as the conduit for a tidal flow of ~ 8 x 109 m 3 /day, in addition to the transport of mud, sand, biogenic material, nutrients, and pollutants. Despite this physical, biological and chemical connection, resource management and prior research have often treated the Delta, Bay and adjacent ocean as separate entities, compartmentalized by artificial geographic or political boundaries. The body of work herein presents a comprehensive analysis of system-wide behavior, extending a rich heritage of sediment transport research that dates back to the groundbreaking hydraulic mining-impact research of G.K. Gilbert in the early 20th century.

California↗

USGS2020

Sediment export and impacts associated with river delta channelization compound estuary vulnerability to sea-level rise, Skagit River Delta, Washington, USA

Improved understanding of the budget and retention of sediment in river deltas is becoming increasingly important to mitigate and plan for impacts expected with sea level rise. In this study, analyses of historical bathymetric change, sediment core stratigraphy, and modeling are used to evaluate the sediment budget and environmental response of the largest river delta in the U.S. Pacific Northwest to western land-use change beginning in ~1850. An estimated 142±28 M m 3 of sediment accumulated offshore of the emergent Skagit River delta in Washington State between 1890 and 2014 and ~68% of which was found in sand deposits. The fraction of sediment retained in sand reservoirs represents 83% of the expected fluvial sand delivery over this time suggesting their potential utility to evaluate the relative contribution of different land uses to sediment runoff through time. A significantly higher ratio of sand retention to delivery during the period 1890–1939 coincided with extensive watershed denudation (clear-cut logging) and channel dredging, relative to the period 1940–2014, which was characterized by improved forest practices and sediment management to protect endangered species but also more extensive river channelization. Retention in the delta foreset of 78% of the sand delivered by the river between 1890 and 1939 was associated with extensive sediment bypassing and delta progradation that is shown to be 5–10x higher than rates over the Holocene. Comparable offshore sand retention over time and higher nearshore retention subsequent to 1940 after normalizing for the assumed reduction in sediment runoff with improved forest practices, suggests that channelization has continued to influence sediment export at a magnitude equivalent to the effects of early logging. Adverse impacts of the bypassing sediment regime to natural hazards risk and ecosystem management concerns are discussed, including the role of the lost sediment as a resource to mitigate subsiding coastal lands vulnerable to flood impacts. The sediment budget and coastal change analyses provide a framework for evaluating opportunities to achieve greater resilience across several sectors of coastal land use important in low-lying deltas worldwide.

Washington↗

USGS2000

Mercury bioaccumulation in fish in a region affected by historic gold mining: The South Yuba River, Deer Creek, and Bear River watersheds, California, 1999

Mercury that was used historically for gold recovery in mining areas of the Sierra Nevada continues to enter local and downstream water bodies, including the Sacramento Delta and the San Francisco Bay of northern California. Methylmercury is of particular concern because it is the most prevalent form of mercury in fish and is a potent neurotoxin that bioaccumulates at successive trophic levels within food webs. In April 1999, the U.S. Geological Survey, in cooperation with several other agencies the Forest Service (U.S. Department of Agriculture), the Bureau of Land Management, the U.S. Environmental Protection Agency, the California State Water Resources Control Board, and the Nevada County Resource Conservation District began a pilot investigation to characterize the occurrence and distribution of mercury in water, sediment, and biota in the South Yuba River, Deer Creek, and Bear River watersheds of California. Biological samples consisted of semi-aquatic and aquatic insects, amphibians, bird eggs, and fish. Fish were collected from 5 reservoirs and 14 stream sites during August through October 1999 to assess the distribution of mercury in these watersheds. Fish that were collected from reservoirs included top trophic level predators (black basses, Micropterus spp.) intermediate trophic level predators [sunfish (blue gill, Lepomis macrochirus; green sunfish, Lepomis cyanellus; and black crappie, Poxomis nigromaculatus)] and benthic omnivores (channel catfish, Ictularus punctatus). At stream sites, the species collected were upper trophic level salmonids (brown trout, Salmo trutta) and upper-to-intermediate trophic level salmonids (rainbow trout, Oncorhynchus mykiss). Boneless and skinless fillet portions from 161 fish were analyzed for total mercury; 131 samples were individual fish, and the remaining 30 fish were combined into 10 composite samples of three fish each of the same species and size class. Mercury concentrations in samples of black basses (Micropterus spp.), including largemouth, smallmouth, and spotted bass, ranged from 0.20 to 1.5 parts per million (ppm), wet basis. Mercury concentrations in sunfish ranged from less than 0.10 to 0.41 ppm (wet). Channel catfish had mercury concentrations from 0.16 to 0.75 ppm (wet). The range of mercury concentrations observed in rainbow trout was from 0.06 to 0.38 ppm (wet), and in brown trout was from 0.02 to 0.43 ppm (wet). Mercury concentrations in trout were greater than 0.3 ppm in samples from three of 14 stream sites. Mercury at elevated concentrations may pose a health risk to piscivorous wildlife and to humans who eat fish on a regular basis. Data presented in this report may be useful to local, state, and federal agencies responsible for assessing the potential risks associated with elevated levels of mercury in fish in the South Yuba River, Deer Creek, and Bear River watersheds.

California↗

USGS2017

Loads and yields of deicing compounds and total phosphorus in the Cambridge drinking-water source area, Massachusetts, water years 2009–15

The source water area for the drinking-water supply of the city of Cambridge, Massachusetts, encompasses major transportation corridors, as well as large areas of light industrial, commercial, and residential land use. Because of the large amount of roadway in the drinking-water source area, the Cambridge water supply is affected by the usage of deicing compounds and by other constituents that are flushed from such impervious areas. The U.S. Geological Survey (USGS) has monitored surface-water quality in the Cambridge Reservoir and Stony Brook Reservoir Basins, which compose the drinking-water source area, since 1997 (water year 1998) through continuous monitoring and the collection of stream-flow samples. In a study conducted by the USGS, in cooperation with the City of Cambridge Water Department, concentrations and loads of calcium (Ca), chloride (Cl), magnesium (Mg), sodium (Na), and sulfate (SO 4 ) were estimated from continuous records of specific conductance and streamflow for streams and tributaries at 10 continuous water-quality monitoring stations. These data were used to characterize current (2015) water-quality conditions, estimate loads and yields, and describe trends in Cl and Na in the tributaries and main-stem streams in the Cambridge Reservoir and Stony Brook Reservoir Basins. These data also were used to describe how stream-water quality is related to various basin characteristics and provide information to guide future management of the drinking-water source area. Water samples from 2009–15 were analyzed for physical properties and concentrations of Ca, Cl, Mg, Na, potassium (K), SO 4 , and total phosphorus (TP). Values of physical properties and constituent concentrations varied widely, particularly in composite samples of stormflow from tributaries that have high percentages of constructed impervious areas. Median concentrations of Ca, Cl, Mg, Na, and K in samples collected from the tributaries in the Cambridge Reservoir Basin (27.2, 273, 4.7, 154.5, and 2.8 milligrams per liter (mg/L), respectively) were higher than those for the Stony Brook Reservoir Basin (22.2, 128, 4.3, 77.1, and 2.5, respectively). Differences between tributary samples for concentrations of Cl and Na were related to the percentage of developed land and constructed impervious area in the drinking-water source area. Median concentrations of SO 4 in samples collected from the tributaries in the Cambridge Reservoir Basin (10.7 mg/L) were lower than those for the Stony Brook Reservoir Basin (18.0 mg/L). Concentrations of dissolved Cl and Na in samples and those concentrations estimated from continuous records of specific conductance (particularly during base flow) often were greater than the U.S. Environmental Protection Agency (EPA) secondary drinking-water standard for Cl (250 mg/L), the chronic aquatic-life guideline for Cl (230 mg/L), and the Massachusetts Department of Environmental Protection drinking-water guideline for Na (20 mg/L). Concentrations of TP (range from 0.008 to 0.69 mg/L in all subbasins) in tributary samples did not differ substantially between the Cambridge Reservoir and Stony Brook Reservoir Basins. About one-half of the concentrations of TP in samples collected during water years 2013–15 exceeded the EPA proposed reference concentration of 0.024 mg/L. For most tributaries, about 70 percent of the annual loads of Ca, Cl, Mg, Na, and SO 4 were associated with base flow. Concentrations of major ions were negatively correlated with streamflow, indicating that these constituents were diluted during stormflow and tend to increase during the summer when streamflow is low. In contrast, between 57 and 92 percent of the annual load for TP was transported during stormflows. Mean annual yields of Ca, Cl, Mg, Na, and SO 4 in the drinking-water source area were 13, 75, 2.6, 40, and 6.9 metric tons per square kilometer, respectively, for water years 2009–15. The mean annual yield of TP in the drinking-water source area for water years 2013–15 was 0.012 metric tons per square kilometer. Yields for major ions and TP were highest in tributary subbasins adjacent to Interstate 95. Temporal trends in mean annual concentrations for Cl and Na were not significant for water years 1998‒2015 (period of record by the USGS) for the outlet of the Cambridge Reservoir and for the main stem of Stony Brook downstream from the reservoir. Median values of base-flow concentrations of TP at three stations were higher for samples collected during base-flow conditions during water years 2005–7 than for samples collected during water years 2013–15. However, the results were not significant for statistical tests between concentrations in samples collected during storms for the same periods, indicating that the quality of stormwater remains similar.

Massachusetts↗

USGS2014

Associations between water physicochemistry and Prymnesium parvum presence, abundance, and toxicity in west Texas reservoirs

Toxic blooms of golden alga ( Prymnesium parvum ) have caused substantial ecological and economic harm in freshwater and marine systems throughout the world. In North America, toxic blooms have impacted freshwater systems including large reservoirs. Management of water chemistry is one proposed option for golden alga control in these systems. The main objective of this study was to assess physicochemical characteristics of water that influence golden alga presence, abundance, and toxicity in the Upper Colorado River basin (UCR) in Texas. The UCR contains reservoirs that have experienced repeated blooms and other reservoirs where golden alga is present but has not been toxic. We quantified golden alga abundance (hemocytometer counts), ichthyotoxicity (bioassay), and water chemistry (surface grab samples) at three impacted reservoirs on the Colorado River; two reference reservoirs on the Concho River; and three sites at the confluence of these rivers. Sampling occurred monthly from January 2010 to July 2011. Impacted sites were characterized by higher specific conductance, calcium and magnesium hardness, and fluoride than reference and confluence sites. At impacted sites, golden alga abundance and toxicity were positively associated with salinity-related variables and blooms peaked at ~10°C and generally did not occur above 20°C. Overall, these findings suggest management of land and water use to reduce hardness or salinity could produce unfavorable conditions for golden alga.

Journal of the American Water Resources Associatio↗