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USGS2009

Data from theodolite measurements of creep rates on San Francisco Bay region faults, California

Introduction Our purpose is to annually update our creep-data archive on San Francisco Bay region active faults for use by the scientific research community. Earlier data (1979-2001) were reported in Galehouse (2002) and were analyzed and described in detail in a summary report (Galehouse and Lienkaemper, 2003). A complete analysis of our earlier results obtained on the Hayward Fault was presented in Lienkaemper, Galehouse and Simpson (2001) and updated in Lienkaemper and others (2012). Lienkaemper and others (2014) provide a new overview and analysis of fault creep along all sections of the northern San Andreas Fault system, from which they estimate by how much fault creep reduces the seismic hazard for each fault section. From 1979 until his retirement from the project in 2001, Jon Galehouse of San Francisco State University (SFSU) and many student research assistants measured creep (aseismic slip) rates on these faults. The creep measurement project, which was initiated by Galehouse, continued through the Geosciences Department at SFSU from 2001-2006 under the direction of Karen Grove and John Caskey (Grove and Caskey, 2005) and since 2006 under Caskey (2007). Forrest McFarland has managed most of the technical and logistical project operations, as well as data processing and compilation since 2001. Data from 2001-2007 are found in McFarland and others (2007). From 2009 onward, we have released the raw data annually using this report (OF2009-1119) as a permanent publication link, while publishing more detailed analyses of these data in the scientific literature, such as Lienkaemper and others (2014). We maintain a project Web site (http://funnel.sfsu.edu/creep/) that includes the following information: project description, project personnel, creep characteristics and measurement, map of creep-measurement sites, creep-measurement site information, and links to data plots for each measurement site. Our most current, annually updated results are, therefore, accessible to the scientific community and to the general public. Information about the project can currently be requested by the public by an email link ( fltcreep@sfsu.edu) found on our project Web site.

California↗

USGS1978

A simple-harmonic model for depicting the annual cycle of seasonal temperatures of streams

Due to economic or operational constraints, stream-temperature records cannot always be collected at all sites where information is desired or at frequencies dictated by continuous or near-continuous surveillance requirements. For streams where only periodic measurements are made during the year, and that are not appreciably affected by regulation or by thermal loading , a simple harmonic function may adequately depict the annual seasonal cycle of stream temperature at any given site. Resultant harmonic coefficients obtained from available stream-temperature records may be used in the following ways: (1) To interpolate between discrete measurements by solving the harmonic function at specified times, thereby filling in estimates of stream-temperature values; (2) to characterize areal or regional patterns of natural stream-temperature values; (2) to characterize areal or regional patterns of natural stream-temperature conditions; and (3) to detect and to assess any significant at a site brought about by streamflow regulation or basin development. Moreover, less-than-daily or sampling frequencies at a given site may give estimates of annual variation of stream temperatures that are statistically comparable to estimates obtained from a daily or continuous sampling scheme. The latter procedure may result in potential savings of resources in network operations, with negligible loss in information on annual stream-temperature variations. (Woodard -USGS)

Open-File Report↗

USGS1938

Fifty-ninth annual report of the Director of the Geological Survey

Basically important in the general program of conservation and development were the results of the Geological Survey's work during the fiscal year 1938. Investigations of the Nation's mineral and water supplies were conducted with all possible vigor and dispatch, thousands of square miles were surveyed for topographic maps, and technical supervision was given to prospecting, mining, and producing operations on public and Indian lands. This work was accomplished through the use of the regularly appropriated funds, the co-operative funds from States, counties, and municipalities, the funds transferred from other departments of the Government for types of work within the Survey's field, and the emergency funds derived chiefly from the Public Works Administration and devoted largely to mapping of various types and to studies of floods. The aggregate expenditures amounted to $5,248,000, which was 265,000 less than the amount expended during the preceding year.

Annual Report↗

USGS2011

Summary of juvenile salmonid passage and survival at McNary Dam-Acoustic survival studies, 2006-09

Passage and survival data were collected at McNary Dam between 2006 and 2009. These data have provided critical information for resource managers to implement structural and operational changes designed to improve the survival of juvenile salmonids as they migrate past the dam. Given the importance of these annual studies, the primary objectives of this report were to summarize the findings of these annual studies to ensure that passage and survival metrics are consistently calculated and reported across all years and to consolidate this information in a single document, thereby making it easier to reference. It is worth noting that this report does not contain all the information from all the annual reports. The intent of this report was to summarize the key findings from multiple years of research. The reader is encouraged to reference the annual reports if more detailed information is needed. Chapter 1 summarizes existing behavior, passage, and survival results for fish released 10 rkm upstream of McNary Dam and from the McNary Dam tailrace during 2006-09. Chapter 2 summarizes existing behavior, passage, and survival results for fish released in the mid-Columbia River and detected at McNary Dam during 2006-09. Results from 2006 indicated that higher spill discharge generally resulted in higher fish passage through spill, and in turn, higher fish survival through the entire dam. Within the spillway, passage effectiveness was highest for the south spill bays, adjacent to the powerhouse. Increased passage in this area, combined with detailed 3-dimensional approach paths, aided in the design and location of the temporary spillway weirs (TSWs) at McNary Dam prior to the 2007 migration of juvenile salmonids. During the 2007 study, the TSWs were tested under two spill treatments during the spring and summer: a "2006 Modified spill," and a "2007 test spill." In the spring, slightly higher discharge through spill bays 14-17 was the primary difference between the spill treatments tested. During the summer, spill treatments were characterized by a high (60 percent) and low (40 percent) percent flow of the total discharge going through the spillway. Flow through the TSWs represented about 7-8 percent of total project discharge in spring and about 10-11 percent of total project discharge in summer. Overall, the TSWs passed 24 percent of yearling Chinook salmon and 27 percent of subyearling Chinook salmon, but passed about 65 percent of juvenile steelhead. In spring, there was little evidence for an effect of spill treatment on either fish passage or survival, however, this was not surprising given there was a relatively small difference between spill treatments. For subyearling Chinook salmon during the summer study, high spill discharge resulted in higher fish passage through the spillway and lower fish passage through the powerhouse. Season wide survival (paired-release) for yearling and subyearling Chinook salmon was 0.98 and 0.92 (SE<0.04) through TSW 20, and 0.96 and 0.97 (SE<0.04) through TSW 22, respectively. Season-wide survival (single-release) for juvenile steelhead was 0.98 (SE=0.024) through TSW 20, and 0.90 (SE=0.02) through TSW 22. The extent to which location and structural design contributed to the differences observed between the two TSWs was uncertain. Nonetheless, the TSWs performed similarly to surface-oriented fish passage structures at other locations and appear to be a useful fish passage alternative at McNary Dam. The 2008 and 2009 studies confirmed previous results showing high survival for fish passing through the TSWs, especially juvenile steelhead. Although the number of all fish species passing through the TSWs was lower in 2008 and 2009 compared to 2007, fish passage efficiency for juvenile steelhead and subyearling Chinook salmon was higher in years with the TSWs, compared to 2006, before the TSWs were in place.

Washington;Oregon↗

USGS1906

Twenty-seventh annual report of the Director of the United States Geological Survey

During the last fiscal year the character of the work and the organization of the force remained substantially the same as described in the Twenty-sixth Annual Report. Accounts of the work performed in geology and paleontology, chemistry and physics, topography and geography, and hydrography, hydrology, and hydro-economics, as well as in the lines of publication and administration, will be found on later pages. Appropriations and allotments .--A plan of operations, including an itemized statement of the appropriations, amounting to $1,513,482.30, and the allotments thereof, was approved by the Secretary of the Interior on May 15, 1905. The work of the year conformed to this plan, copies of which are on file at the Department and the Survey. State cooperation .--Many of the States, following a well-established policy, cooperated with the National Survey in geologic, topographic, and hydrographic work; details are given on pages 12, 29, 72, and 74.

Annual Report↗

USGS1978

Implementation plan for Bolivian Mineral Exploration Fund

Bolivia ranks second among world producers of tin and antimony, and first in bismuth production. Mineral exports in 1975 were valued at $314.2 million, nearly 60 percent of the value of all exports, and petroleum product exports totalled nearly $157 million, or 30 percent of the total. Tin accounted for 58 percent of the total value of metallic mineral exports. The central government derived about 19 percent of its total tax revenues in 1975 from the mining sector. The mining sector consists of the large, medium, and small mining subsectors, a classification established by the government. Individual operations are referred to as large, medium, or small depending upon the subsector into which they are classified. All large mining enterprises are owned and operated by a government corporation, COMIBOL; the medium and small operations are privately owned. COMIBOL's exports in 1975 were valued at $171.8 million or 70 percent of the total mineral exports; the medium mines accounted for $55.5 million or 23 percent, and the small mines for $17.5 million or 7 percent of the total. The combination of high operating costs, low productivity, inadequate ore reserves, and insufficient risk capital for exploration and development has led to the realization that there is an urgent need to improve the situation for mining in Bolivia. Proposals are being studied to revise the tax code, a program is underway to evaluate selected mineral deposits for possible exploration and development, and programs are under consideration to encourage minerals exploration. A minerals exploration plan is proposed which would offer technical and financial aid to various segments in the minerals field. A program, estimated to cost between $2 million and $2.5 million annually, and to be operated by a new agency in the Ministry of Mining and Metallurgy, is outlined.

Open-File Report↗

USGS1995

Statistical summaries of surface-water hydrologic data collected in the Suwannee River Water Management District, Florida, 1906-93

Since 1906, hydrologic data have been collected systematically on streams and lakes in the Suwannee River Water Management District (SRWMD) by the U.S. Geological Survey (USGS), the SRWMD, and other agencies. Records of stream discharge and stream and lake stage in the SRWMD (fig. 1), collected largely in cooperation with the SRWMD since 1975, have been published for many years in the USGS annual report series "Water Resources Data for Florida." Streamflow and stream and lake elevation statistics are given in this report for sites shown in figure 1. All 27 daily streamflow stations shown are (or were) operated by the USGS in cooperation with the SRWMD; all 18 lake stage stations shown are now (1994) operated by the SRWMD, but were operated until the late 1970’s by the USGS in cooperation with the SRWMD. All unregulated stream stations which have three or more years of continuous record are included in this report. All unregulated lake stations having at least three years of intermittent lake elevation readings are also included. There are many other sites in the SRWMD for which shorter records or miscellaneous measurements are available but are not included because statistical summaries for such stations require interpretive analysis beyond the scope of this report. Basic hydrologic data have long been recognized as fundamental to the analysis of magnitude and frequency of floods, availability of water supplies, potential for reservoir storage, and permitting of waste discharges. Also, in recent times, scientists and water managers have become more aware of the complex relations between flows and water levels and the terrestrial and aquatic plant and animal life in wetland ecosystems. In 1994, the SRWMD and the USGS began a long-term program of cooperative studies designed to better understand minimum and maximum flow and water levels needed to manage the surface and ground water resources of the District and maintain or improve the various ecosystems therein. Information presented in this report, together with frequency analysis of station data, flow regionalization, studies of the relation of salinity to flow in the lower Suwannee River, definition of ground-water surface-water interactions, surface- and ground-water quality studies, and studies of interaction between surface-water bodies and wetlands, will provide the basis for the SRWMD to establish minimum flow and level requirements for streams and lakes in the SRWMD area. This report is a necessary first step in the longterm program of study because it contains basic stream discharge and stream and lake elevation statistics, most of which are not contained in the annual report "Water Resources Data for Florida." These statistics, most of which were generated using a U.S. Geological Survey computer program, ADAPS, Automatic Data Processing System, characterize normal flows and levels and departures from normal due to floods and droughts or seasonal climatic variations. Specifically, the report presents for the period of record of each stream or lake gaging station, as appropriate: Minimum, maximum, and mean of monthly mean stream elevations and discharges in graphical and tabular form. For streams, annual mean discharge, highest and lowest annual mean discharge, highest and lowest daily mean discharge, minimum annual seven-day mean discharge, instantaneous peak discharge and elevation, instantaneous minimum discharge, and basin yield. Duration of annual daily mean stream elevation and discharge. Duration of daily values are shown in both graphical and tabular form. Duration of daily mean stream elevations and discharge, by months, in tables. Minimum and maximum 1-,3-,7-,14-,30-, 60-, 90-,120-, and 183-consecutive day stream elevations and discharges (with rankings) for each year of record. Mean monthly lake elevations and statistics by month, including number of monthly values, mean, variance, standard deviation, skewness, and coefficient of variation. For convenience, a GLOSSARY of commonly used terms related to the collection and reporting of surface-water elevations and discharge is included before the Introduction section of this report. The authors wish to acknowledge Natalie Rackley, formerly of the U.S. Geological Survey, and T.W. Grubbs, U.S. Geological Survey, for their computer assistance in the compilation of station records, and Jim Tomberlin, U.S. Geological Survey, for the mapping of stream and lake gaging stations.

Florida↗

USGS2006

Water-quality characteristics of Montana streams in a statewide monitoring network, 1999-2003

A statewide monitoring network of 38 sites was operated during 1999-2003 in cooperation with the Montana Department of Environmental Quality to provide a broad geographic base of water-quality information on Montana streams. The purpose of this report is to summarize and describe the water-quality characteristics for those sites. Samples were collected at U.S. Geological Survey streamflow-gaging stations in the Missouri, Yellowstone, and Columbia River basins for stream properties, nutrients, suspended sediment, major ions, and selected trace elements. Mean annual streamflows were below normal during the period, which likely influenced water quality. Continuous water-temperature monitors were operated at 26 sites. The median of daily mean water temperatures for the June-August summer period ranged from 12.5 degC at Kootenai River below Libby Dam to 23.0 degC at Poplar River near Poplar and Tongue River at Miles City. In general, sites in the Missouri River basin commonly had the highest water temperatures. Median daily mean summer water temperatures at four sites (Jefferson River near Three Forks, Missouri River at Toston, Judith River near Winifred, and Poplar River near Poplar) classified as supporting or marginally supporting cold-water biota exceeded the general guideline of 19.4 degC for cold-water biota. Median daily mean temperatures at sites in the network classified as supporting warm-water biota did not exceed the guideline of 26.7 degC for warm-water biota, although several sites exceeded the warm-water guideline on several days during the summer. More...

Scientific Investigations Report↗

USGS1984

Statistical summaries of streamflow data in Oregon; Volume 1, eastern Oregon

Statistical summaries of streamflow data at 335 streamgaging sites are presented in this two volume report to aid in appraising the hydrology of river basins in Oregon. Records for 31 gaging stations were compiled into separate periods owing to changes in regulation during the period of data collection. The periods before and after regulation are presented for comparison. A brief station description is given describing the physical and operational features for each gaging station. Following the station description are tables of monthly and annual flow statistics, flood frequency data, low-flow and high-flow frequency data, and flow-duration information. (USGS)

Oregon↗

USGS2003

Effect of the Paradox Valley Unit on the dissolved-solids load of the Dolores River near Bedrock, Colorado, 1988-2001

Discharge of brine with an average dissolved-solids concentration of about 256,000 milligrams per liter from alluvium in Paradox Valley, a collapsed salt anticline, substantially increases the dissolved-solids load of the Dolores River. In 1996, the Bureau of Reclamation began operation of the Paradox Valley Unit, a series of brine-withdrawal wells completed in alluvium along the Dolores River and a deep-injection well for the brine, to decrease flow of brine into the river. This report presents the findings of a study to determine the effectiveness of the Paradox Valley Unit from 1988 through September 2001. Differences in dissolved-solids load of the Dolores River between two gaging stations, one upstream and one downstream from the Paradox Valley Unit, indicate that an average dissolved-solids load of about 313 tons per day (an annual average of about 115,000 tons) was contributed by brine inflow to the Dolores River before operation of the Paradox Valley Unit began in July 1996. By September 30, 2001, the dissolved-solids load contributed by brine had declined to an average of about 29 tons per day? a decrease of about 90 percent. This decrease might have been facilitated by a decrease in precipitation and streamflow into the Paradox Valley during the last few years of the assessed period.

Colorado↗

USGS2018

Pacific Northwest Aquatic Monitoring Partnership 2017 Annual Report

The Pacific Northwest Aquatic Monitoring Partnership (PNAMP) continued to promote the integration of monitoring resources and development of tools to support monitoring in 2017. Improved coordination and integration of goals, objectives, and activities among Pacific Northwest monitoring programs is essential to improving the quality and consistency of monitoring in the region. PNAMP operates through inter-organizational teams to make progress on a variety of projects identified to support partner needs and PNAMP goals. These teams are largely ad hoc and formed for the specific purpose of achieving the objectives of the identified projects. For each project, the PNAMP Coordination Team identified interested Steering Committee (SC) members and subject matter experts to form the working teams that provide guidance and leadership. In addition, the teams acted as an intermediate between the larger group of interested participants and the SC, thus maintaining the concept of better SC/participant exchange. The PNAMP Coordination Team continued to facilitate dialog among experts to move forward with ongoing and new projects. In addition, the Coordination Team continued their efforts to track in-kind contributions of time from participants at meetings, workshops, and other PNAMP hosted events; in 2017 this estimate amounted to 2,039 hours by 67 organizations.

Report↗

USGS2021

Evaluation of a two-season banding program to estimate and model migratory bird survival

The management of North American waterfowl is predicated on long-term, continental scale banding implemented prior to the hunting season (i.e., July–September) and subsequent reporting of bands recovered by hunters. However, single-season banding and encounter operations have a number of characteristics that limit their application to estimating demographic rates and evaluating hypothesized limiting factors throughout the annual cycle. We designed and implemented a 2-season banding program for American black ducks ( Anas rubripes ), mallards ( A . platyrhynchos ), and hybrids in eastern North America to evaluate potential application to annual life cycle conservation and sport harvest management. We assessed model fit and compared estimates of annual survival among data types (i.e., pre-hunting season only [July–September], post-hunting season only [January–March], and 2-season [pre- and post-hunting season]) to evaluate model assumptions and potential application to population modeling and management. There was generally high agreement between estimates of annual survival derived using 2-season and pre-season only data for all age and sex cohorts. Estimates of annual survival derived from post-season banding data only were consistently higher for adult females and juveniles of both sexes. We found patterns of seasonal survival varied by species, age, and to a lesser extent, sex. Hunter recovered birds exhibited similar spatial distributions regardless of banding season suggesting banded samples were from the same population. In contrast, Goodness-Of-Fit tests suggest this assumption was statistically violated in some regions and years. We conclude that estimates of seasonal and annual survival for black ducks and mallards based on the 2-season banding program are valid and accurate based on model fit statistics, similarity in survival estimates across data and models, and similarities in the distribution of recoveries. The 2-season program provides greater precision and insight into the survival process and will improve the ability of researchers and managers to test competing hypotheses regarding population regulation resulting in more effective management.

Ecological Applications↗

USGS2006

Ground-Water Levels in Huron County, Michigan, 2004-05

In 1990, the U.S. Geological Survey (USGS) completed a study of the hydrogeology of Huron County, Michigan (Sweat, 1991). In 1993, Huron County and the USGS entered into a continuing agreement to measure water levels at selected wells throughout Huron County. As part of the agreement, USGS has operated four continuous water-level recorders, installed from 1988 to 1991 on wells in Bingham, Fairhaven, Grant, and Lake Townships (fig. 1) and summarized the data collected in an annual or bi-annual report. The agreement was altered in 2003, and beginning January 1, 2004, only the wells in Fairhaven and Lake Townships retained continuous waterlevel recorders, while the wells in Grant and Bingham Townships reverted primarily to periodic or quarterly measurement status. USGS also has provided training for County or Huron Conservation District personnel to measure the water level, on a quarterly basis, in 25 wells. USGS personnel regularly accompany County or Huron Conservation District personnel to provide a quality assurance/quality control check of all measurements being made. Water-level data collected from the 25 periodically or quarterly-measured wells is summarized in an annual or bi-annual report. In 1998, the USGS also completed a temporal and spatial analysis of the monitoring well network in Huron County (Holtschlag and Sweat, 1998). The altitude of Lake Huron and precipitation are good indicators of general climatic conditions and, therefore, provide an environmental context for ground-water levels in Huron County. Figure 2 shows the mean-monthly water-level altitude of Lake Huron, averaged from measurements made by the U.S. Army Corps of Engineers at sites near Essexville or Harbor Beach, or both (National Oceanic and Atmospheric Administration, 2003-05), and monthly precipitation measured in Bad Axe (National Oceanic and Atmospheric Administration, 2003-05). In March 2003, a new low-water level for the period from 1991 through 2005 was measured in Lake Huron. There was almost no net change in the water level of Lake Huron from January 2004 through December 2005. In 2004, annual precipitation measured in Port Hope was about 3.7 inches above normal, but precipitation measured in Bad Axe was about 1.4 inches below normal. About 14.5 inches of precipitation was measured in Bad Axe during the 2004 summer growing season (May through August), which is about the same as was measured in Port Hope during the same period. Provisional precipitation totals for 2005 were 30.7 inches for January through November in Port Hope, and about 31.7 inches for the year in Bad Axe. About 10.6 inches of precipitation was measured in Bad Axe during the 2005 summer growing season, which is about 0.2 inches more than was recorded at Port Hope during the same period. Two wells equipped with continuous-data recorders are completed in the Saginaw and Marshall aquifers in Fairhaven and Lake Townships, respectively. From January 2004 through December 2005, the net rise in the water level in the Fairhaven Township well was 0.71 ft, and the net rise in the Lake Township well was 0.98 ft. The Fairhaven Township well is drilled adjacent to Saginaw Bay (Lake Huron), and, as previously noted, there was almost no net change in the water level in Saginaw Bay over the same period. Hydrographs showing water levels are presented for the two wells equipped with continuous-data recorders. Continuous-data recorders were discontinued in the Grant and Bingham Township wells at the end of 2003 due to budget constraints. The decision of which two wells to discontinue was based on an analysis of the intrinsic value to Huron County of data from each well. The Grant Township well was selected for periodic or quarterly measurement at that time because it is completed in the glacial aquifer, which is little used for drinking water purposes or absent in much of Huron County. The Bingham Township well, which is completed in the Marshall aquifer, was selected for periodic or quarterly measurement because water levels in the well are often perturbed as a result of pumpage from nearby production wells and do not reflect baseline conditions within the aquifer. Twenty five wells were measured on a periodic or quarterly basis in 2004-05. These wells are completed in the glacial, Saginaw, and Marshall aquifers, and the Coldwater confining unit. Although each quarterly measurement only provides a “snapshot” water level (measured in feet below land surface), the data adequately define the generalized water-level trend in the aquifer near the well. Water levels in 15 quarterlymeasured wells had a net rise ranging from 0.20 to 1.31 ft for the period from January 2004 to December 2005, while water levels in 10 of the wells had a net decline ranging from 0.07 to 0.99 ft over the same period (fig. 3; table 1). Period-of-record (the time period when water levels have been measured by U.S. Geological Survey or their cooperators) minimum depths to water (high-water levels) were measured in March 2004 in two quarterly-measured wells completed in the Marshall aquifer in Lake and Hume Townships. Period-of-record maximum depths to water were measured in September 2005 in three wells completed in the Marshall aquifer near Bad Axe. Water levels in those three wells recovered about 3 to 5 ft between September and December 2005. No period-of-record minimum or maximum depths to water were measured for the period from January 2004 through December 2005 in wells completed in either the glacial and Saginaw aquifers, or the Coldwater confining unit. Hydrographs showing water levels measured in each well are presented for the 25 wells measured on a quarterly basis. Water-level trends measured for the period from January 2004 through December 2005 in other wells in Lower Michigan have similarities to those measured in Huron County wells. Several external factors influence water-level trends including proximity to nearby production wells, amount and timing of precipitation events, evapotranspiration and type of prevalent ground cover, proximity of aquifer to the surface, and hydraulic characteristics of overlying geologic materials.

Michigan↗

USGS2008

Ground-water levels in Huron County, Michigan, 2002-03

In 1990, the U.S. Geological Survey (USGS) completed a study of the hydrogeology of Huron County, Michigan (Sweat, 1991). In 1993, Huron County and the USGS entered into a continuing agreement to collect water-level altitudes (hereafter referred to as water levels) at selected wells throughout Huron County. As part of the agreement, USGS has operated four continuous water-level recorders, installed from 1988 to 1991 on wells in Bingham, Fairhaven, Grant, and Lake Townships (fig. 1) and summarized the data collected in an annual or bi-annual report. The agreement was altered in 2003, and beginning January 1, 2004, only the wells in Fairhaven and Lake Townships will have continuous water-level recorders, while the wells in Grant and Bingham Townships will revert to quarterly measurement status. USGS has also provided training for County or Huron Conservation District personnel to measure the water level, on a quarterly basis, in 23 wells. USGS personnel regularly accompany County or Huron Conservation District personnel to provide a quality assurance/quality control check of all measurements being made. Water-level data collected from the 23 quarterly-measured wells is also summarized in the annual or bi-annual report. In 1998, the USGS also completed a temporal and spatial analysis of the monitoring well network in Huron County (Holtschlag and Sweat, 1998). The altitude of Lake Huron and precipitation are good indicators of general climatic conditions and, therefore, provide an environmental context for groundwater levels in Huron County. Figure 2 shows the mean-monthly water-level altitude of Lake Huron, averaged from measurements made by the U.S. Army Corps of Engineers at sites near Essexville and Harbor Beach, and monthly precipitation measured in Bad Axe (National Oceanic and Atmospheric Administration [NOAA], 2002-04; Danny Costello, NOAA hydrologist, written commun., 2003-04). In March 2003, a new low-water level for the period of this study was measured in Lake Huron (National Oceanic and Atmospheric Administration, 2003; 2004). The net decline in the water level of Lake Huron from January 1, 2002 to December 31, 2003 was about 0.3 ft. Annual precipitation in 2002 was about 0.3 inches above normal, with much of it occurring during summer months. The provisional precipitation total for 2003 is about an inch below normal (NOAA, 2003, 2004; Danny Costello, NOAA hydrologist, written commun., 2003, 2004). Four wells equipped with continuous-data recorders are completed in the glacial, Saginaw, and Marshall aquifers. Water levels in three of the four wells equipped with continuous-data recorders experienced a net decline over the period from January 2002 to December 2003, while the level in well H9r, completed in the Saginaw aquifer in Fairhaven Township adjacent to Saginaw Bay (Lake Huron), rose about 1.3 ft over the same period. Interestingly, the water level in Saginaw Bay declined about 0.3 ft over the same period. A period-ofrecord maximum depth to water was recorded in September 2003 in well H25Ar, completed in the Marshall aquifer in Lake Township. Hydrographs showing altitude of the water surface are presented for each of four wells equipped with continuous-data recorders. Twenty three wells were measured on a quarterly basis in 2002-03. These wells are completed in the Saginaw and Marshall aquifers, and Coldwater confining unit. Although each quarterly measurement only provides a “snapshot” water level, the data adequately define the “generalized” water-level trend in the aquifer near the well. The water level in one quarterly-measured well completed in the Saginaw aquifer near Saginaw Bay, had a net rise for the period from January 2002 to December 2003, while levels in the other 22 quarterly-measured wells declined about 0.5 to 2.0 ft during the same period. A period-of-record minimum depth to water (high) was measured in 2002 in two quarterly-measured wells completed in the Saginaw aquifer, although the level in one of those wells had a net decline over the period from January 2002 through December 2003. Conversely, period-of-record maximum depths to water (low) were measured in 2002 in one well completed in the Saginaw aquifer and two wells completed in the Marshall aquifer; and in 2003, in 6 of 16 wells completed in the Marshall aquifer. Near period-ofrecord maximum depths to water were measured in 2003 in two additional wells completed in the Marshall aquifer. No period-of-record minimum or maximum depths to water were measured in 2002-03 in wells completed in the Coldwater confining unit. Hydrographs showing water levels measured in each well are presented for the 23 wells measured on a quarterly basis. Water-level trends measured in 2002-03 in other wells in Lower Michigan have similarities to those measured in Huron County wells. Several external factors appear to influence water-level trends including proximity to nearby production wells, amount and timing of precipitation events, evapotranspiration and type of prevalent ground cover, proximity of aquifer to the surface, and hydraulic characteristics of overlying geologic materials.

Michigan↗

USGS2006

Ground-water levels in Huron County, Michigan, 2004-05

Michigan↗

USGS2019

Using the STARS model to evaluate the effects of the proposed action for the reinitiation of consultation on the coordinated long-term operation of the Central Valley and State Water Project

In 2016, the U.S. Bureau of Reclamation (USBR) and California Department of Water Resources requested a reinitiation of consultation under Section 7 of the Endangered Species Act on the coordinated long-term operations of the Central Valley and State Water Projects. This resulted in a Biological Assessment released by USBR in 2019. In its analysis of the Biological Assessment for its Biological Opinion on the proposed action, the National Marine Fisheries Service (NMFS) requested assistance from the U.S. Geological Survey to describe the effect of the proposed action on juvenile Chinook salmon ( Oncorhynchus tshawytscha ) populations migrating through the Sacramento-San Joaquin River Delta (henceforth called “the Delta”). Therefore, in this report we analyzed an 82-year time series of simulated river flows and Delta Cross Channel (DCC) gate operations under two scenarios constructed for the Biological Assessment: the proposed-action (PA) scenario and the continuing-operations scenario (COS). To evaluate the proposed action, we used the STARS model ( S urvival, T ravel time, A nd R outing S imulation model), a stochastic, individual-based simulation model designed to predict survival of a cohort of fish that experiences variable daily river flows as the fish migrate through the Delta. The STARS model uses parameter estimates from a Bayesian mark-recapture model that jointly estimates travel time and survival in eight discrete reaches of the Delta and migration routing at two key river junctions. By applying the STARS model to the two 82-year scenarios, we found that the proposed action had negative effects on survival, travel time, and routing in October–December but positive effects in April–June. In October–December, there was a high probability that survival in the PA scenario was less than that in the COS, and that travel time and routing to the Interior Delta for the PA scenario was greater than that for the COS. The magnitude of the difference in survival between scenarios was larger in some years than in others. For example, we quantified that survival under the PA scenario was 10 percent lower than under the COS in 25 percent of the water years from October through December. During this period, inflow to the Delta tended to be lower under the PA scenario, and the DCC gate was open more frequently under the PA scenario than during the COS. Lower inflow reduces survival, and more frequent operation of the DCC gate 1) increases the proportion of fish entering the Interior Delta, where survival is low, and thus 2) reduces survival in the Sacramento River in reaches downstream of the DCC. In contrast, during the period April–June, survival was higher, travel times were lower, and routing to the Interior Delta was lower under the PA scenario relative to the COS, although the magnitude of the increase in survival was relatively small in most years (less than a 3-percent difference in survival). This difference between scenarios was driven by higher river flows in some years under the PA scenario relative to the COS. Overall, the differences in survival, travel time, and routing distance between the two operational scenarios were primarily driven by the timing and magnitude of the annual high river flows.

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USGS2017

Designing a high-frequency nutrient and biogeochemical monitoring network for the Sacramento–San Joaquin Delta, northern California

Executive Summary This report is the third in a series of three reports that provide information about how high-frequency (HF) nutrient monitoring may be used to assess nutrient inputs and dynamics in the Sacramento–San Joaquin Delta, California (Delta). The purpose of this report is to provide the background, principles, and considerations for designing an HF nutrient-monitoring network for the Delta to address high-priority, nutrient-management questions. The report starts with discussion of the high-priority management questions to be addressed, continues through discussion of the questions and considerations that place demands and constraints on network design, discusses the principles applicable to network design, and concludes with the presentation of three example nutrient-monitoring network designs for the Delta. For three example network designs, we assess how they would address high-priority questions that have been identified by the Delta Regional Monitoring Program (Delta Regional Monitoring Program Technical Advisory Committee, 2015). This report, along with the other two reports of this series (Kraus and others, 2017; Downing and others, 2017), was drafted in cooperation with the Delta Regional Monitoring Program to help scientists, managers, and planners understand how HF data improve our understanding of nutrient sources and sinks, drivers, and effects in the Delta. The first report in the series (Kraus and others, 2017) provides an introduction to the reasons for and fundamental concepts behind using HF monitoring measurements, including a brief summary of nutrient status and trends in the Delta and an extensive literature review showing how and where other research and monitoring programs have used HF monitoring to improve our understanding of nutrient cycling. The report covers the various technologies available for HF nutrient monitoring and presents the different ways HF monitoring instrumentation may be used for both fixed station and spatial assessments. Finally, it presents numerous examples of how HF measurements are currently (2017) being used in the Delta to examine how nutrients and nutrient cycling are related to aquatic habitat conditions. The second report in the series (Downing and others, 2017) summarizes information about HF nutrient and associated biogeochemical monitoring in the north Delta. The report synthesizes data available from the nutrient and water quality monitoring network currently (2017) operated by the U.S. Geological Survey in this ecologically important region of the Delta. In the report, we present and discuss the available data at various timescales—first at the monthly, seasonal, and inter-annual timescales; and, second, for comparison, at the tidal and event timescales. As expected, we determined that there is substantial variability in nitrate concentrations at short timescales, such as within a few hours, but also significant variability at longer timescales such as months or years. This high variability affects calculation of fluxes and loads, indicating that HF monitoring is necessary for understanding and assessing flux-based processes and outcomes in Delta tidal environments.

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USGS2017

An introduction to high-frequency nutrient and biogeochemical monitoring for the Sacramento–San Joaquin Delta, northern California

Executive Summary This report is the first in a series of three reports that provide information about high-frequency (HF) nutrient and biogeochemical monitoring in the Sacramento–San Joaquin Delta of northern California (Delta). This first report provides an introduction to the reasons for and fundamental concepts behind collecting HF measurements, and describes the benefits associated with a real-time, continuous, HF, multi-parameter water quality monitoring station network that is co-located with flow stations. It then provides examples of how HF nutrient measurements have improved our understating of nutrient sources and cycling in aquatic systems worldwide, followed by specific examples from the Delta. These examples describe the ways in which HF instrumentation may be used for both fixed-station and spatial assessments. The overall intent of this document is to describe how HF measurements currently (2017) are being used in the Delta to examine the relationship between nutrient concentrations, nutrient cycling, and aquatic habitat conditions. The second report in the series (Downing and others, 2017) summarizes information about HF nutrient and associated biogeochemical monitoring in the northern Delta. The report synthesizes data available from the nutrient and water quality monitoring network currently operated by the U.S. Geological Survey in this ecologically important region of the Delta. In the report, we present and discuss the available data at various timescales—first, at the monthly, seasonal, and inter-annual timescales; and, second, for comparison, at the tidal and event (for example, storms, reservoir releases, phytoplankton blooms) timescales. As expected, we determined that there is substantial variability in nitrate concentrations at short timescales within hours, but also significant variability at longer timescales such as months or years. This multi-scale, high variability affects calculation of fluxes and loads, indicating that HF monitoring is necessary for understanding and assessing flux-based processes and outcomes in tidal environments, such as the Delta. The third report in the series (Bergamaschi and others, 2017) provides information about how to design HF nutrient and biogeochemical monitoring for assessment of nutrient inputs and dynamics in the Delta. The report provides background, principles, and considerations for designing an HF nutrient-monitoring network for the Sacramento–San Joaquin Delta to address high-priority, nutrient-management questions. The report starts with high-priority management questions to be addressed, continues with questions and considerations that place demands and constraints on network design, discusses the principles applicable to network design, and concludes with the presentation of three example nutrient‑monitoring network designs for the Delta. For the three example networks, we assess how they would address high-priority questions identified by the Delta Regional Monitoring Program (Delta Regional Monitoring Program Technical Advisory Committee, 2015).

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