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USGS2024

Quality of groundwater used for domestic supply in the eastern Sacramento Valley and adjacent foothills, California

Summary More than 2 million Californians rely on groundwater from privately owned domestic wells for drinking-water supply. This report summarizes a water-quality survey of domestic and small-system drinking-water supply wells in the eastern Sacramento Valley and adjacent foothills where more than 25,000 residents are estimated to use privately owned domestic wells. Study results show that inorganic and organic constituents in groundwater were present above regulatory (maximum contaminant level, MCL) benchmarks for public drinking-water quality in 8 and 3 percent, respectively, of the aquifer area used for domestic drinking-water supply (herein, “domestic groundwater resources”; fig. 1). The only inorganic constituent detected above regulatory benchmarks was arsenic. The only organic constituent exceeding regulatory benchmarks was the fumigant 1,2,3-trichloropropane (1,2,3-TCP). Three additional organic constituents—the disinfection by-product chloroform, the gasoline oxygenate methyl tert -butyl ether (MTBE), and the solvent tetrachloroethene (PCE)—were detected at low concentrations below one-tenth of regulatory benchmarks in 34, 10, and 10 percent of domestic groundwater resources, respectively. Total dissolved solids (TDS), iron, and manganese exceeded non-regulatory aesthetic guidelines for drinking water in 5, 10, and 26 percent of domestic groundwater resources, respectively. Per- and polyfluoroalkyl substances (PFASs) were detected in 29 percent of domestic groundwater resources,with 5 percent exceeding the recently enacted (April 2024) U.S. Environmental Protection Agency MCLs. Total coliform and enterococci bacteria were detected in 13 and 8 percent of domestic groundwater resources, respectively. Redox sensitive constituents in this study included arsenic, manganese, nitrate, and iron. In the lower elevation portions of the eastern Sacramento Valley study area, reducing conditions in groundwater aquifers promote elevated arsenic, iron, and manganese, and conversely lower concentrations of nitrate. The presence of the volatile organic compound (VOC) 1,2,3-TCP was related to its past history in select agricultural land uses (on orchards or vineyards) in the Sacramento Valley; however, unlike in the San Joaquin Valley where orchards and vineyards are more common, its detection frequency was low (only detected in one well in this study). Chloroform was frequently detected in this study at low levels. Chloroform is a disinfection byproduct commonly found in domestic wells treated by shock chlorination. The solvent PCE is among the most frequently detected VOCs in groundwater, which is primarily related to its long history of use and its persistence in groundwater in oxic conditions. The gasoline oxygenate MTBE was a contaminant introduced to groundwater through atmospheric exchange when it was used as a fuel additive to decrease smog inducing emissions from vehicles. Its occurrence in groundwater at low levels is expected and makes it a potentially useful tracer of relatively recent recharge water being withdrawn from wells. The PFASs are anthropogenic chemicals with hundreds of uses, and they have been incorporated into many different products, processes, and applications worldwide. Like MTBE, the occurrence of PFASs in groundwater may be in part due to atmospheric exchange, but there are several other pathways that contribute PFASs to the environment.

California↗

USGS1987

Ground-water levels in water years 1984-86 and estimated ground-water pumpage in water years 1984-85, Carson Valley, Douglas County, Nevada

Tabulations of groundwater level measurements made during the water years 1984-86 and summaries of estimated pumpage for water years 1984 and 1985 in Carson valley, Douglas County, Nevada, are included in this report. The data are being collected to provide a record of long-term groundwater changes and pumpage estimates that can be incorporated in a groundwater model change at a later date. (USGS)

Open-File Report↗

USGS1988

Statistical summaries of streamflow records in Oklahoma and parts of Arkansas, Missouri, and Texas through 1984

Statistical summaries of streamflow records through 1984 for gaging stations in Oklahoma and parts of adjacent states are presented in this report. Records are presented for 148 stations with at least 10 years of unregulated or regulated streamflow. Streamflow at 70 of the stations is regulated for certain perdiods. Data for these periods were analyzed separately to account for changes in streamflow due to regulating structures. For each gaging station, a brief description of the location, drainage area and period of record is given. For those stations with a regulated streamflow record, a brief regulation history is given also. This information is followed by tables of monthly and annual discharge statistics, low- and high-flow frequency statistics, peak-flow frequency statistics, and flow-duration statistics. Daily flow-duration hydrographs are included for most stations.

Arkansas, Missouri, Oklahoma, Texas↗

USGS1996

Level II scour analysis for Bridge 37 (BARTTH00080037) on Town Highway 8, crossing Willoughby River, Barton, Vermont

This report provides the results of a detailed Level II analysis of scour potential at structure BARTTH00080037 on town highway 8 crossing the Willoughby River, Barton, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S. Department of Transportation, 1993). Results of a Level I scour investigation also are included in Appendix E of this report. A Level I investigation provides a qualitative geomorphic characterization of the study site. Information on the bridge, gleaned from Vermont Agency of Transportation (VTAOT) files, was compiled prior to conducting Level I and Level II analyses and is found in Appendix D. The site is in the New England Upland section of the New England physiographic province of north-central Vermont in the town of Barton. The 60.4-mi 2 drainage area is in a predominantly rural and forested basin. In the vicinity of the study site, the banks have sparse to moderate woody vegetation coverage. In the study area, the Willoughby River is probably incised, has a sinuous channel with a slope of approximately 0.009 ft/ft, an average channel top width of 108 ft and an average channel depth of 6 ft. The predominant channel bed material is cobble (D 50 is 95.1 mm or 0.312 ft). The geomorphic assessment at the time of the Level I and Level II site visit on October 20, 1994, indicated that the reach was stable. The town highway 8 crossing of the Willoughby River is a 96-ft-long, two-lane bridge consisting of one 94-foot steel-beam span (Vermont Agency of Transportation, written communication, August 4, 1994). The bridge is supported by vertical, concrete abutments with wingwalls. The channel is skewed approximately 15 degrees to the opening while the opening-skew-to-roadway is 10 degrees. No scour was reported in the channel or along abutments or wingwalls during the Level I assessment. Type-2 stone fill (less than 24 inches diameter) was reported at each abutment and all four wingwalls. Additional details describing conditions at the site are included in the Level II Summary and Appendices D and E. Scour depths and rock rip-rap sizes were computed using the general guidelines described in Hydraulic Engineering Circular 18 (Richardson and others, 1993). Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. Data in appendix D (Vermont Agency of Transportation, written communication, August 4, 1994) indicate that the right abutment may be founded on or near marble bedrock which may limit scour depths. Bedrock was not detected by borings in the vicinity of the left abutment. The scour analysis results are presented in tables 1 and 2 and a graph of the scour depths is presented in figure 8. Contraction scour for all modelled flows was 0 ft. Abutment scour ranged from 7.3 to 10.7 ft and the worst-case abutment scour occurred at the 500-year discharge. Additional information on scour depths and depths to armoring are included in the section titled “Scour Results”. Scoured-streambed elevations, based on the calculated scour depths, are presented in tables 1 and 2. A cross-section of the scour computed at the bridge is presented in figure 8. Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1993, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.

Vermont↗

USGS2023

Grassland management priorities for the North Central Region

Executive Summary Understanding how climate change and variability will impact grassland ecosystems is crucial for successful grassland management in the 21st century. In 2020, the U.S. Geological Survey North Central Climate Adaptation Science Center (USGS NC CASC) began a project to establish a baseline of information to best serve grassland managers (that is, those who develop grassland management plans or implement those plans on the ground) at Federal, State, and Tribal agen-cies and nongovernmental organizations to help meet regional grassland management goals. This project “A Synthesis of Climate Impacts, Stakeholder Needs, and Adaptation in Northern Great Plains Grassland Ecosystems” (hereafter, the Grasslands Synthesis Project), had two primary goals: (1) to synthesize management goals and challenges for grassland managers across the region and (2) to assess the state-of-the-science and identify knowledge gaps for addressing the goals and challenges within the context of climate change. The findings from the Grasslands Syn-thesis Project are described in two volumes. This report serves several purposes, including providing (1) a synthesis of regional grassland management goals and challenges, (2) identification of information needs relevant to grassland management in a changing climate, and (3) summaries of grassland management issues by ecoregion and management organization or agency.

Colorado, Kansas, Montana, Nebraska, Noth Dakota, ↗

USGS1989

Riparian ecosystem creation and restoration: a literature summary

Riparian ecosystems generally compose a minor proportion of surrounding areas, but typically are more structurally diverse and more productive in plant and animal biomass than adjacent upland areas. Riparian areas supply food, cover, and water (especially important in the arid West) for a large diversity of animals, and serve as migration routes and forest connectors between habitats for a variety of wildlife, particularly ungulates and birds. Because riparian ecosystems often are relatively small areas and occur in conjunction with waterways, they are vulnerable to severe alteration. Riparian ecosystems throughout the U.S. have been heavily impacted by man's activities. Riparian ecosystem creation and restoration have been used as mitigation for project impacts from highway, bridge, and pipeline construction; water development; flood control channel modifications; industrial and residential development; agriculture; irrigation; livestock grazing; mining; and accidental habitat loss. Creation of a riparian ecosystem in| a more mesic upland area (e.g., ‘grassland or cropland) adjacent to a river requires appropriate water supply and grading the topography to suitable elevations to support plantings of riparian vegetation. Restoration involves returning the ecosystem to pre disturbance conditions and typically implies revegetation. Removing exotic vegetation or restoring water supplies to pre disturbance level also may be involved. Enhancement of riparian ecosystems commonly refers to improving existing conditions to increase habitat value, usually by increasing plant or community diversity to increase value for wildlife. Managing a riparian ecosystem typically involves enhancement techniques. However, creation and restoration projects often involve use of techniques considered more management-oriented (e.g., fencing to prevent cattle grazing until planted vegetation of a created or restored wetland is established). Protection of an existing riparian ecosystem from impact should be of utmost importance during planning and construction phases of development projects. If loss or damage is unavoidable, wetland creation or restoration can be used as mitigation. Compared to other wetland types (e.g., coastal wetlands), projects and techniques involving creation or restoration of riparian ecosystems are not well documented. For example, only 8% of the records in the WCR Data Base contained information on riparian ecosystems, whereas 31% of the records contained information on coastal emergent or forested ecosystems. To provide a source of currently available literature, riparian information from 92 records (primarily published papers or reports) in the U.S. Fish and Wildlife Service's (FWS) Wetland Creation-Restoration (WCR) Data Base (Schneller-McDonald et al. 1988) was used to develop a literature summary of creation and restoration of riparian ecosystems. The summary provides an overview of the status of riparian ecosystems in the U.S., a discussion of several riparian functions, and a review of some techniques used for planning, implementing, monitoring, and measuring project success of creation-restoration efforts. Case studies of various creation or restoration projects are used to demonstrate these techniques and to report some results of their use. Several well-documented case studies are discussed in detail to illustrate more extensive efforts to plan, implement, or monitor riparian ecosystem creation-restoration projects. For the purpose of this report, riparian ecosystems are defined as landscapes adjacent to drainageways of floodplains that exhibit vegetation, soil, and hydrologic mosaics along topographic and moisture gradients that are distinct from the predominant landscape surface types. Major plant communities are described under palustrine system in Cowardin et al. (1979). Literature from the WCR Data Base was used to provide a summary of riparian ecosystem creation-restoration literature. Thus, information concerning natural systems is not included unless discussed in these articles. This focus allows the reader to compare relative information available on riparian ecosystem creation-restoration efforts. However, this focus also results in limited information in some sections of the report (e.g., Status of Riparian Ecosystems in the U.S.). Individuals involved in riparian ecosystem creation-restoration efforts are encouraged to thoroughly examine available literature on natural and altered systems. Brinson et al. (1981) provide a comprehensive review and synthesis of the ecology and status of riparian ecosystems. Over 500 articles are cited in their 124-page report. Chapters include the following topics: status of riparian ecosystems in the U.S., ecological functions and properties of riparian ecosystems (e.g., geomorphology, primary productivity, nutrient cycling, hydrology), importance of riparian ecosystems to fish and wildlife, and considerations in valuation (ecologic and economic) of riparian ecosystems. Brinson et al. (1981) also discuss management of riparian ecosystems. Riparian ecosystem management literature was not included in the WCR Data Base, unless the article also discussed creation or restoration.

Report↗

USGS1993

National Research Program of the Water Resources Division, U. S. Geological Survey, Fiscal Year 1992

This report, one in a series of annual reports, provides current information about the National Research Program (NRP) of the U.S. Geological Survey's Water Resources Division (WRD) during fiscal year 1992. Organized by NRP's six research disciplines, the volume contains a summary of the problem, objective, approach, and progress for each project that was active during fiscal year 1992. It also contains bibliographic information that, because of the long-term nature of the program, covers a 5-year period. The bibliographic information does not include abstracts or informal reports. Rather it contains those reports that are readily available in the form of journal articles, U.S. Geological Survey (USGS) publications, book chapters, or books.

Open-File Report↗

USGS1981

Digital seismograms of aftershocks of the Imperial Valley, California, earthquake of October 15, 1979

This report presents the digital seismograms collected for the aftershocksof the Imperial Valley, California earthquake (M L = 6.6) that occurred onL October 15, 1979. A short summary follows that describes the field procedures, instrumentation, and routine computer analysis that was used to produce the ground motion time histories. Boore and Fletcher (1981) may be referenced for selected fault plane solutions, spectra and moments. Requests for digital time histories on magnetic tape may be made to the Branch of Ground Motion and Faulting, Menlo Park, California.

California↗

USGS1952

Flood of August 1950 in the Waimea area, Kauai, Hawaii

On August 15-18, 1950, Waimea River on the island of Kauai, T. H., had one of the severest floods in its history as a result of torrential rains, caused by a storm associated with the only typhoon ever recorded in the proximity of the Hawaiian Archipelego. At one rainfall station in the basin, 50 inches of rain was recorded during a 72- hour period. Kawaikoi Stream, in the headwaters of Waimea River basin, reached a maximum discharge of 7, 980 second-feet, or 1,950 second-feet per square mile. A rubble wall along the right bank of Waimea River just below the mouth of Makaweli River, constructed to contain the flow, was overtopped and the entire town of Waimea was flooded. The water was about a foot over the top of the wall at most places. No lives were lost, but damage to property was about $200, 000. This report presents detailed records of stages and discharges at four gaging stations in the basin during the flood period August 15-18 in the Waimea River basin, a summary of flood discharges at gaging stations on the principal streams on the island of Kauai, a description of the physical features of the drainage basin, a description of the two types of storms that prevail on the Hawaiian Islands, and a section on the meteorology of the storm of August 15-18. Figure 46 is a map of the island of Kauai, which shows the location of the gaging stations referred to in this report, the location of .rain gages in the area where rainfall was the greatest, and lines of equal rainfall for the period August 14-19, 1950.

Hawaii↗

USGS1969