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At least 37 records · Page 2Linked to original sources
USGS2021

Growth of the wildland-urban interface within and around U.S. National Forests and Grasslands, 1990-2010

The wildland-urban interface (WUI), where housing is in close proximity to or intermingled with wildland vegetation, is widespread throughout the United States, but it is unclear how this type of housing development affects public lands. We used a national dataset to examine WUI distribution and growth (1990–2010) in proximity to National Forests and created a typology to characterize each National Forest’s combination of WUI area and housing growth. We found that National Forests are hotspots for WUI growth, with a 38% increase in WUI area and 46% growth in WUI houses from 1990 to 2010, in excess of WUI growth for the conterminous U.S. Growth within National Forests was higher than the surrounding area. Diffuse intermix WUI, where houses are intermingled with wildland vegetation, is common within National Forests, but WUI houses around National Forests were primarily in denser interface WUI areas, which lack substantial wildland vegetation. WUI was more prevalent within and around National Forests in the East, while National Forests in the West experienced higher rates of WUI growth. National Forests with the most challenging WUI issues—extensive WUI area and rapid growth in intermix and interface—were found primarily in the South and interior West. Given the diversity of WUI landscapes, effectively responding to current and future WUI challenges will require both engagement with individual homeowners dispersed throughout National Forests, as well as increased emphasis on mitigating denser interface development around National Forests. At a time when wildfire risks are expected to intensify due to climate change, and 75% of privately owned land within and around National Forests is not yet WUI, understanding WUI growth patterns in proximity to public lands is vital for land management and human well-being.

Landscape and Urban Planning↗
USGS2022

Discovery and potential ramifications of reduced iron-bearing nanoparticles — Magnetite, wüstite, and zero-valent iron — In wildland–urban interface fire ashes

The increase in fires at the wildland–urban interface has raised concerns about the potential environmental impact of ash remaining after burning. Here, we examined the concentrations and speciation of iron-bearing nanoparticles in wildland–urban interface ash. Total iron concentrations in ash varied between 4 and 66 mg g −1 . Synchrotron X-ray absorption near-edge structure (XANES) spectroscopy of bulk ash samples was used to quantify the relative abundance of major Fe phases, which were corroborated by transmission electron microscopy measurements. Maghemite (γ-(Fe 3+ ) 2 O 3 ) and magnetite (γ-Fe 2+ (Fe 3+ ) 2 O 4 ) were detected in most ashes and accounted for 0–90 and 0–81% of the spectral weight, respectively. Ferrihydrite (amorphous Fe( III )–hydroxide, (Fe 3+ ) 5 HO 8 ·4H 2 O), goethite (α-Fe 3+ OOH), and hematite (α-Fe 3+ 2 O 3 ) were identified less frequently in ashes than maghemite and magnetite and accounted for 0–65, 0–54, and 0–50% of spectral weight, respectively. Other iron phases identified in ashes include wüstite (Fe 2+ O), zerovalent iron, FeS, FeCl 2 , FeCl 3 , FeSO 4 , Fe 2 (SO 4 ) 3 , and Fe(NO 3 ) 3 . Our findings demonstrate the impact of fires at the wildland–urban interface on iron speciation; that is, fires can convert iron oxides ( e.g. , maghemite, hematite, and goethite) to reduced iron phases such as magnetite, wüstite, and zerovalent iron. Magnetite concentrations ( e.g. , up to 25 mg g −1 ) decreased from black to gray to white ashes. Based on transmission electron microscopy (TEM) analyses, most of the magnetite nanoparticles were less than 500 nm in size, although larger particles were identified. Magnetite nanoparticles have been linked to neurodegenerative diseases as well as climate change. This study provides important information for understanding the potential environmental impacts of fires at the wildland–urban interface, which are currently poorly understood.

Environmental Science Nano↗
USGS2001

User interface for ground-water modeling: Arcview extension

Numerical simulation for ground-water modeling often involves handling large input and output data sets. A geographic information system (GIS) provides an integrated platform to manage, analyze, and display disparate data and can greatly facilitate modeling efforts in data compilation, model calibration, and display of model parameters and results. Furthermore, GIS can be used to generate information for decision making through spatial overlay and processing of model results. Arc View is the most widely used Windows-based GIS software that provides a robust user-friendly interface to facilitate data handling and display. An extension is an add-on program to Arc View that provides additional specialized functions. An Arc View interface for the ground-water flow and transport models MODFLOW and MT3D was built as an extension for facilitating modeling. The extension includes preprocessing of spatially distributed (point, line, and polygon) data for model input and postprocessing of model output. An object database is used for linking user dialogs and model input files. The Arc View interface utilizes the capabilities of the 3D Analyst extension. Models can be automatically calibrated through the Arc View interface by external linking to such programs as PEST. The efficient pre- and postprocessing capabilities and calibration link were demonstrated for ground-water modeling in southwest Kansas.

Journal of Hydrologic Engineering↗
USGS2012

Phast4Windows: A 3D graphical user interface for the reactive-transport simulator PHAST

Phast4Windows is a Windows® program for developing and running groundwater-flow and reactive-transport models with the PHAST simulator. This graphical user interface allows definition of grid-independent spatial distributions of model properties—the porous media properties, the initial head and chemistry conditions, boundary conditions, and locations of wells, rivers, drains, and accounting zones—and other parameters necessary for a simulation. Spatial data can be defined without reference to a grid by drawing, by point-by-point definitions, or by importing files, including ArcInfo® shape and raster files. All definitions can be inspected, edited, deleted, moved, copied, and switched from hidden to visible through the data tree of the interface. Model features are visualized in the main panel of the interface, so that it is possible to zoom, pan, and rotate features in three dimensions (3D). PHAST simulates single phase, constant density, saturated groundwater flow under confined or unconfined conditions. Reactions among multiple solutes include mineral equilibria, cation exchange, surface complexation, solid solutions, and general kinetic reactions. The interface can be used to develop and run simple or complex models, and is ideal for use in the classroom, for analysis of laboratory column experiments, and for development of field-scale simulations of geochemical processes and contaminant transport.

Groundwater↗
USGS2000

2nd interface between ecology and land development in California

The 2nd Interface Between Ecology and Land Development Conference was held in association with Earth Day 1997, five years after the first Interface Conference. Rapid population growth in California has intensified the inevitable conflict between land development and preservation of natural ecosystems. Sustainable development requires wise use of diminishing natural resources and, where possible, restoration of damaged landscapes. These Earth Week Celebrations brought together resource managers, scientists, politicians, environmental consultants, and concerned citizens in an effort to improve the communication necessary to maintain our natural biodiversity, ecosystem processes and general quality of life. As discussed by our keynote speaker, Michael Soule, the best predictor of habitat loss is population growth and nowhere is this better illustrated than in California. As urban perimeters expand, the interface between wildlands and urban areas increases. Few problems are more vexing than how to manage the fire prone ecosystems indigenous to California at this urban interface. Today resource managers face increasing challenges of dealing with this problem and the lead-off section of the proceedings considers both the theoretical basis for making decisions related to prescribed burning and the practical application. Habitat fragmentation is an inevitable consequence of development patterns with significant impacts on animal and plant populations. Managers must be increasingly resourceful in dealing with problems of fragmentation and the often inevitable consequences, including susceptibility to invasive oganisms. One approach to dealing with fragmentation problems is through careful landplanning. California is the national leader in the integration of conservation and economics. On Earth Day 1991, Governor Pete Wilson presented an environmental agenda that promised to create between land owners and environmentalists, agreements that would guarantee the protection of -endangered species and out of this grew the pioneering initiative, known as the Natural Communities Conservation Planning (NCCP) program. California's vast expanse of seemingly endless resources has traditionally been viewed as justification for abusive land use practices. The modem day recognition that resources are finite has led to greater concern, not only for conserving what is left, but for restoring abused landscapes. Ecological restoration is a new science devoted to returning disturbed environments to a semblance of their 'pristine' state. Based on principles of 'revegetation,' restoration goes far beyond simple replanting, rather the ambition of ecological restoration is to return landscapes to functioning ecosystems and is the focus of the last section.

Open-File Report↗
USGS2020

Use of time domain electromagnetic soundings and borehole electromagnetic induction logs to delineate the freshwater/saltwater interface on southwestern Long Island, New York, 2015–17

The U.S. Geological Survey, in cooperation with the New York State Department of Environmental Conservation, used surface and borehole geophysical methods to delineate the freshwater/saltwater interface in coastal plain aquifers along the southwestern part of Long Island, New York. Over pumping of groundwater in the early 20th century combined with freshwater/saltwater interfaces at the coastline created saltwater intrusion in the upper glacial, Jameco, Magothy, and Lloyd aquifers. This study documents, for the first time, extensive saltwater intrusion of the Lloyd aquifer along the southwestern coast of Long Island, N.Y. Several public-supply wells in the southern parts of Nassau, Queens, and Kings Counties have been adversely affected by saltwater intrusion causing supply wells to be shutdown and abandoned. Due to the ongoing groundwater pumping in southern Nassau County, the freshwater/saltwater interface requires delineation and monitoring for any inland movement. In 2015–17, the U.S. Geological Survey collected time domain electromagnetic soundings at 12 locations and borehole electromagnetic induction conductivity logs at 9 wells within the study area to delineate several saltwater intrusion wedges. The upper glacial, Jameco, and Magothy aquifers were grouped into one aquifer complex within the study area to simplify interpretations. The coastal plain sediments increase in thickness from west to east and north to south because of their regional dip toward the southeast. Three separate wedges, shallow, intermediate, and deep, of saltwater intrusion were delineated in the upper glacial, Jameco, and Magothy aquifer complex. In addition, analysis of geophysical logs collected in an open borehole of a test well in southern Queens County in 1989 revealed the Lloyd aquifer was nearly completely intruded by saltwater with an estimated chloride concentration of 15,000 milligrams per liter. The geophysical logs from this well provides, for the first time, definitive proof of saltwater intrusion of the Lloyd aquifer on Long Island’s south shore, suggesting the freshwater/saltwater interface was at the coastline and not miles offshore as theorized by previous studies.

New York↗
USGS2021

Chemical and structural degradation of CH3NH3PbI3 propagate from PEDOT:PSS interface in the presence of humidity

Understanding interfacial reactions that occur between the active layer and charge-transport layers can extend the stability of perovskite solar cells. In this study, the exposure of methylammonium lead iodide (CH 3 NH 3 PbI 3 ) thin films prepared on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)-coated glass to 70% relative humidity (R.H.) leads to a perovskite crystal structure change from tetragonal to cubic within 2 days. Interface-sensitive photoluminescence measurements indicate that the structural change originates at the PEDOT:PSS/perovskite interface. During exposure to 30% R.H., the same structural change occurs over a much longer time scale (>200 days), and a reflection consistent with the presence of (CH 3 ) 2 NH 2 PbI 3 is detected to coexist with the cubic phase by X-ray diffraction pattern. The authors propose that chemical interactions at the PEDOT:PSS/perovskite interface, facilitated by humidity, promote the formation of dimethylammonium, (CH 3 ) 2 NH 2 + . The partial A-site substitution of CH 3 NH 3 + for (CH 3 ) 2 NH 2 + to produce a cubic (CH 3 NH 3 ) 1− x [(CH 3 ) 2 NH 2 ] x PbI 3 phase explains the structural change from tetragonal to cubic during short-term humidity exposure. When (CH 3 ) 2 NH 2 + content exceeds its solubility limit in the perovskite during longer humidity exposures, a (CH 3 ) 2 NH 2 + -rich, hexagonal phase of (CH 3 NH 3 ) 1− x [(CH 3 ) 2 NH 2 ] x PbI 3 emerges. These interfacial interactions may have consequences for device stability and performance beyond CH 3 NH 3 PbI 3 model systems and merit close attention from the perovskite research community.

Advanced Materials Interfaces↗
USGS2019

Quantitative guidance for efficient vertical flow measurements at the sediment-water interface using temperature-depth profiles

Upward discharge to surface water bodies can be quantified using analytical models based on temperature-depth (T-z) profiles. The use of sediment T-z profiles is attractive as discharge estimates can be obtained using point-in-time data that are collected inexpensively and rapidly. Previous studies have identified that T-z methods can only be applied at times of the year when there is significant difference between the streambed-water interface and deeper sediment temperatures (e.g., winter and summer). However, surface water temperatures also vary diurnally, and the influence of these variations on discharge estimates from T-z methods is poorly understood. For this study, synthetic T-z profiles were generated numerically using measured streambed interface temperature data to assess the influence of diurnal temperature variations on discharge estimation and provide insight into the suitable application of T-z methods. Results show that the time of day of data collection can have a substantial influence on vertical flux estimates using T-z methods. For low groundwater discharge fluxes (e.g. 0.1 m d-1), daily transience in streambed temperatures led to relatively large errors in estimated flow magnitude and direction. For higher discharge fluxes (1.5 m d-1), the influence of transient streambed temperatures on discharge estimates was strongly reduced. Discharge estimates from point-in-time T-z profiles were most accurate when the uppermost point in the T-z profile was near the bed interface daily mean (two time periods daily). Where temperature time series data are available, daily averaged T-z profiles can produce accurate discharge estimates across a wide range of discharge rates. Seasonality in shallow groundwater temperature generally had a negligible influence on vertical flow estimates. These findings can be used to plan field campaigns and provide guidance on the optimal application of T-z methods to quantify vertical groundwater discharge to surface water bodies.

Hydrological Processes↗
USGS2017

Managing the livestock– Wildlife interface on rangelands

On rangelands the livestock–wildlife interface is mostly characterized by management actions aimed at controlling problems associated with competition, disease, and depredation. Wildlife communities (especially the large vertebrate species) are typically incompatible with agricultural development because the opportunity costs of wildlife conservation are unaffordable except in arid and semi-arid regions. Ecological factors including the provision of supplementary food and water for livestock, together with the persecution of large predators, result in livestock replacing wildlife at biomass densities far exceeding those of indigenous ungulates. Diseases are difficult to eradicate from free-ranging wildlife populations and so veterinary controls usually focus on separating commercial livestock herds from wildlife. Persecution of large carnivores due to their depredation of livestock has caused the virtual eradication of apex predators from most rangelands. However, recent research points to a broad range of solutions to reduce conflict at the livestock–wildlife interface. Conserving wildlife bolsters the adaptive capacity of a rangeland by providing stakeholders with options for dealing with environmental change. This is contingent upon local communities being empowered to benefit directly from their wildlife resources within a management framework that integrates land-use sectors at the landscape scale. As rangelands undergo irreversible changes caused by species invasions and climate forcings, the future perspective favors a proactive shift in attitude towards the livestock–wildlife interface, from problem control to asset management.

Book chapter↗
USGS1990

Fire hazards at the urban-wildland interface: what the public expects

Urban-wildland issues have become among the most contentious and problematic issues for forest managers. Using data drawn from surveys conducted by the authors and others, this article discusses how public knowledge and perceptions of fire policies and fire hazards change over time, the kinds of policy responses homeowners prefer as a way of preventing fire hazards at the urban-wildland interface, and how citizens view their own obligations as participants in interface issues. These data show that public attitudes toward fire have changed significantly over the past two decades and that educating the public about fire and the managers' use of fire can have positive effects on behavior. Yet, modifying the individual's behavior in regard to interface fire risks must also deal with important issues of individual incentives, the distribution of costs, and unanticipated policy impacts.

Environmental Management↗
USGS2020

High-resolution mapping of the freshwater-brine interface using deterministic and Bayesian inversion of airborne electromagnetic data at Paradox Valley, USA

Salt loads in the Colorado River Basin are a primary water quality concern. Natural groundwater brine discharge to the Dolores River where it passes through the collapsed salt anticline of the Paradox Valley in western Colorado is a significant source of salt to the Colorado River. An airborne electromagnetic survey of Paradox Valley has provided insights into the 3D distribution of brine in the surficial aquifer. A combination of stochastic and deterministic resistivity inversions were used to interpret the top of the freshwater-brine interface and to qualitatively describe the vertical salinity gradients across the interface. Low-resistivity regions indicative of brine occur near the land surface where brine discharges to the Dolores River and increase in depth several kilometers up-gradient along the axis of the valley. The most conductive parts of the brine plume are found in the areas below and adjacent to the river, suggesting that the brine becomes shallower and more concentrated as it reaches its natural discharge location. A significant freshwater lens overlying the brine west of the Dolores River is spatially correlated to the intermittent West Paradox Creek and agricultural irrigation. Below this lens, the transition from freshwater to brine appears to occur abruptly over a few meters and correlates to available well information. However, away from these regions and particularly with distance from the river, the freshwater-brine interface appears to be more diffuse.

Colorado↗
USGS2021

Benthic and planktonic inorganic nutrient processing rates at the interface between a river and lake

The interface between lotic and lentic ecosystems is often a zone of intense metabolic activity, as primary production in streams and rivers can be light limited whereas nutrients often limit primary production in lake ecosystems. Our objective was to model the influence that rivermouths (the lotic-lentic interface) could have on the loads of soluble reactive phosphorus (SRP) and dissolved inorganic nitrogen (N) passing from the tributary to the nearshore zone of a lake. To achieve this objective, we modeled the combined role of water column nutrient transformation rates with sediment nutrient flux rates. For sensitivity analysis, we picked plausible parameter ranges based on values previously measured in the Fox rivermouth (a tributary to Lake Michigan). Sensitivity analysis of the model demonstrated that overall the importance of water column processing rates increases with increasing nutrient concentration and discharge. We then applied the model to the Fox rivermouth, simulating the change in nutrients on four dates where all of the necessary parameters had been estimated. This modeling suggests that the Fox rivermouth is often a net sink for SRP and source for ammonia (NH 4 ), with water column processing driving SRP removal and both water column and sediment flux driving NH 4 dynamics. Removal of SRP in the water column means conversion to particulate and/or organic P, and those P pools are generally considered to be less bioavailable than SRP, so it may be that rivermouths disconnect upstream sources of nutrients from nearshore food webs. These results demonstrate that the interface zone between lotic and lentic systems has the potential to substantially alter the load and character of nutrients as river waters pass through rivermouths to adjacent nearshore areas.

Biogeochemistry↗
USGS2011

Investigating the complex interface where bedrock transforms to regolith

The interface where bedrock transforms to regolith is not planar but rather has a roughness that varies with the scale of observation. The complexity of this surface is manifested in both element-depth and fragment size-depth distributions and may sometimes be related to the longitudinal profiles of watershed streams. The fractal nature of the bedrock-regolith interface means that the interface has a “thickness” which is >20 m in two ridgetop examples from Pennsylvania and Puerto Rico. Such weathering thicknesses, modeled as a function of one-dimensional fluid flow, are affected by the balance between rates of weathering and erosion. One-dimensional models are consistent with weathering advance rates that vary with equilibrium solubility and porefluid velocities (and not reaction kinetics). However, fluid flow is not strictly downward and one-dimensional. Permeability of regolith changes as particle size and bulk density changes with depth. Thus, both downward and lateral flow occurs especially at reaction fronts where reactions change permeability. The rate of weathering advance is, therefore, affected by the 3-dimensional distribution of reaction zones that affect permeability across the watershed. Quantitative models of such phenomena over a range of spatial and temporal scales are needed.

Applied Geochemistry↗
USGS2023

A research agenda for the science of actionable knowledge: Drawing from a review of the most misguided to the most enlightened claims in the science-policy interface literature

Linking science with action affords a prime opportunity to leverage greater societal impact from research and increase the use of evidence in decision-making. Success in these areas depends critically upon processes of producing and mobilizing knowledge, as well as supporting and making decisions. For decades, scholars have idealized and described these social processes in different ways, resulting in numerous assumptions that now variously guide engagements at the interface of science and society. We systematically catalog these assumptions based on prior research on the science-policy interface, and further distill them into a set of 26 claims. We then elicit expert perspectives (n = 16) about these claims to assess the extent to which they are accurate or merit further examination. Out of this process, we construct a research agenda to motivate future scientific research on actionable knowledge, prioritizing areas that experts identified as critical gaps in understanding of the science-society interface. The resulting agenda focuses on how to define success, support intermediaries, build trust, and evaluate the importance of consensus and its alternatives – all in the diverse contexts of science-society-decision-making interactions. We further raise questions about the centrality of knowledge in these interactions, discussing how a governance lens might be generative of efforts to support more equitable processes and outcomes. We offer these suggestions with hopes of furthering the science of actionable knowledge as a transdisciplinary area of inquiry.

Environmental Science & Policy↗
USGS1999

210Pb and 210Po, manganese and iron cycling across the O2/H2S interface of a permanently anoxic fjord: Framvaren, Norway

Vertical profiles of dissolved and particulate 201 Po and 210 Pb were measured across the redox transition zone at Station F1 in Framvaren Fjord, Norway. In this fjord, a sharp decrease in pH above the O 2 /H 2 S interface facilitates the aerobic dissolution of MnO 2 . In contrast, Fe(II) concentrations begin to increase only at the O 2 /H 2 S interface depth. Activity profiles reveal that dissolved 210 Po and 210 Pb are sequestered efficiently by particulates in surface waters. As polonium-210 and lead-210 activities descend down into the aerobic manganese reduction (AMR) zone, they are remobilized during the reductive dissolution of the carrier phase oxyhydroxides. Both 210 Po and 210 Pb are highly enriched at the O 2 /H 2 S interface where an active community of microbes, such as anoxygenic phototrophs (e.g., Chromatium, Chlorobium sp.), thrives. The coincident peaks in 210 Po and 210 Pb and microbial biomass suggest a strong biological influence on the behavior of these radionuclides. There is a strong covariance between the vertical distribution of Mn and Pb, indicating that their redox cycling is closely coupled and is likely microbially mediated.

Framveran Fjord↗
USGS2009

Cycling of mercury across the sediment-water interface in seepage lakes: Chapter 13, Advances in Chemistry

The magnitude and direction of Hg fluxes across the sediment—water interface were estimated by groundwater, dry bulk sediment, sediment pore water, sediment trap, and water-column analyses in two northern Wisconsin seepage lakes. Little Rock Lake (Treatment Basin) received no groundwater discharge during the study period (1988—1990), and Follette Lake received continuous groundwater discharge. In Little Rock Lake, settling of particulate matter accounted for the major Hg delivery mechanism to the sediment—water interface. Upward diffusion of Hg from sediment pore waters below 2—4-cm sediment depth was apparently a minor source during summer stratification. Time-series comparisons suggested that the observed buildup of Hg in the hypolimnion of Little Rock Lake was attributable to dissolution and diffusion of Hg from recently fallen particulate matter close to the sediment—water interface. Groundwater inflow represented an important source of new Hg, and groundwater outflow accounted for significant removal of Hg from Pallette Lake. Equilibrium speciation calculations revealed that association of Hg with organic matter may control solubility in well-oxygenated waters, whereas in anoxic environments sulfur (polysulfide and bisulfide) complexation governs dissolved total Hg levels.

Wisconsin↗
USGS2009

Advancing techniques to constrain the geometry of the seismic rupture plane on subduction interfaces a priori: Higher-order functional fits

Ongoing developments in earthquake source inversions incorporate nonplanar fault geometries as inputs to the inversion process, improving previous approaches that relied solely on planar fault surfaces. This evolution motivates advancing the existing framework for constraining fault geometry, particularly in subduction zones where plate boundary surfaces that host highly hazardous earthquakes are clearly nonplanar. Here, we improve upon the existing framework for the constraint of the seismic rupture plane of subduction interfaces by incorporating active seismic and seafloor sediment thickness data with existing independent data sets and inverting for the most probable nonplanar subduction geometry. Constraining the rupture interface a priori with independent geological and seismological information reduces the uncertainty in the derived earthquake source inversion parameters over models that rely on simpler assumptions, such as the moment tensor inferred fault plane. Examples are shown for a number of wellconstrained global locations. We expand the coverage of previous analyses to a more uniform global data set and show that even in areas of sparse data this approach is able to accurately constrain the approximate subduction geometry, particularly when aided with the addition of data from local active seismic surveys. In addition, we show an example of the integration of many two-dimensional profiles into a threedimensional surface for the Sunda subduction zone and introduce the development of a new global threedimensional subduction interface model: Slab1.0. ?? 2009 by the American Geophysical Union.

Geochemistry, Geophysics, Geosystems↗
USGS2005

Graphical user interface for accessing water-quality data for the Devils Lake basin, North Dakota

Maintaining the quality of surface waters in the Devils Lake Basin in North Dakota is important for protecting the agricultural resources, fisheries, waterfowl and wildlife habitat, and recreational value of the basin. The U.S. Geological Survey, in cooperation with local, State, and Federal agencies, has collected and analyzed water-quality samples from streams and lakes in the basin since 1957, and the North Dakota Department of Health has collected and analyzed water-quality samples from lakes in the basin since 2001. Because water-quality data for the basin are important for numerous reasons, a graphical user interface was developed to access, view, and download the historical data for the basin. The interface is a web-based application that is available to the public and includes data through water year 2003. The interface will be updated periodically to include data for subsequent years.

Open-File Report↗