Brian S. Caruso

• Ph.D. Water Resources/Environmental Engineering
• Supervisory Hydrologist/Chief, Division of Water Resources, Region 6 at U.S. Fish and Wildlife Service

Addressing uncertainty in sediment predictions due to land use/land cover (LULC) change could better inform the selection of sediment management options for reservoir sustainability. We used the Nam Kong catchment of the Mekong River Basin in Southern Laos, with two hydropower dams in series, to understand the implications of LULC change uncertaint...

The U.S. Geological Survey, in cooperation with the U.S. Fish and Wildlife Service (FWS), began a study in 2019 to complete the compilation and quality assurance of water-resource threats and needs data for the 117 National Wildlife Refuges (NWRs) in the FWS Legacy Mountain-Prairie Region (LMPR) and to characterize the water-resource threats and ne...

We performed two‐dimensional (2D) hydrodynamic modeling to aid recovery of the endangered razorback sucker (Xyrauchen texanus) by reconnecting the Green River with its historic bottomland floodplain wetlands at Ouray National Wildlife Refuge, Utah. Reconnection allows spring flood flows to overtop the river levee every two to three years, and passi...

Zhovty Vody city, located in south-central Ukraine, has long been an important center for the Ukrainian uranium and iron industries. Uranium and iron mining and processing activities during the Cold War resulted in poorly managed sources of radionuclides and heavy metals. Widespread groundwater and surface water contamination has occurred, which cr...

Quantitative understanding of potential changes in streamflow and sediment load is complicated by uncertainty related to land use change projections which is characterized by a high uncertainty in terms of demand (quantity) and location of changes (spatial distribution). We simulate the Sesan, Srepok, and Sekong Rivers (3S), the most important trib...

Uncertainty in land use change is often overlooked and typically not included in climate change impact studies. This study investigated the uncertainty in flow and sediment projections using the Soil and Water Assessment Tool (SWAT) associated with future land use, future climate scenarios and model parameterization. We use the Sesan, Srepok, and S...

This study models climate change impacts on the natural flow regime of braided rivers and inflows to hydropower lakes in a New Zealand mountain basin. Flow metrics include the magnitude, frequency, timing, and duration of unaltered flows. The TopNet hydrologic model was used to simulate impacts in the Upper Waitaki Basin of the South Island for the...

Reliable projections of discharge and sediment are essential for future water and sediment management plans under climate change, but these are subject to numerous uncertainties. This study assessed the uncertainty in flow and sediment projections using the Soil and Water Assessment Tool (SWAT) associated with three Global Climate Models (GCMs), th...

Future climate change is expected to have wide ranging impacts on the hydrology of mountain rivers because of changes in the magnitudes and timing of rain and snow, as well as the significant spatial variability of topography and other catchment characteristics. In New Zealand, hydropower generation in mountain basins is the primary source of elect...

Wintertime precipitation sample data from 55 Snowpack sites and 17 National Atmospheric Deposition Program (NADP)/National Trends Network Wetfall sites in the Rocky Mountain region were examined to identify long-term trends in chemical concentration, deposition, and precipitation using Regional and Seasonal Kendall tests. The Natural Resources Cons...

A hydrologic connectivity index (HCI) was developed to aid the US Clean Water Act Section 404 jurisdictional evaluation of headwater streams in montane watersheds, using the Cement Creek Watershed in the San Juan Mountains, Colorado as a case study. Jurisdictional determinations are required for many intermittent and ephemeral streams, where signif...

The development of three-dimensional reconstructions of channel morphology has historically been limited by the high costs of geospatial data collection and software modelling. Advances in image processing, sensor technology and portable remote-sensing platforms, however, now offer the opportunity to derive survey quality terrain models at signific...

In this study, sulfate-reducing bioreactors (SRBRs) efficiently treated acid mine drainage (AMD) for a contiguous period of 5 months. The AMD was sourced from an active coal mine on the South Island of New Zealand and typically had a pH < 3, 1700 mg/L of sulfate, 50 mg/L of Fe, 18 mg/L of Al, 15 mg/L of Mn, 4 mg/L of Zn, and lower concentrations of...

This study analyzed stream characteristics in a mountain watershed in southwestern Colorado and developed a three-level hierarchical classification scheme using national datasets to demonstrate jurisdictional evaluation as “waters of the United States (U.S.)” under U.S. Clean Water Act Section 404 at the watershed scale. The National Hydrography Da...

The braided rivers and floodplains in the Upper Waitaki Basin (UWB) of the South Island of New Zealand are critical habitats for endangered and threatened fauna such as the black stilt. However, this habitat has degraded due to introduced predators, hydropower operations, and invasive weeds including Russell lupins. While conservation efforts have...

During the past decade, the advances in survey and sensor technology and three-dimensional morphologic analysis have been partially driven by the need for high resolution topography for physical and numerical fluvial modeling and have in return created new opportunities to investigate and model the structure and dynamics of fluvial systems. While t...

Wetlands in mountain environments provide critical ecosystem services but are increasingly threatened by agricultural land use intensification. This study evaluates agricultural nonpoint source nutrient pollution transport in a wetland–stream–lake complex in a mountain, tussock grassland catchment in the South Island, New Zealand. Flow and water-qu...

In mountain braided rivers, extreme flow variability, floods and high flow pulses are fundamental elements of natural flow regimes and drivers of floodplain processes, understanding of which is essential for management and restoration. This study evaluated flow dynamics and invasive vegetation characteristics and changes in the Ahuriri River, a fre...

The natural flow paradigm suggests that components of the natural streamflow regime and variability should be managed to maintain important ecosystem functions and services. Mountain rivers can exhibit extreme flow variability and provide critical aquatic habitat and ecosystem services but can be severely impacted by hydroelectric power (HEP) devel...

Statistical and deterministic modelling estimates of flood magnitudes and frequencies that can affect flood-plain ecology in the upper Ahuriri River catchment, a mountainous high country catchment in the New Zealand Southern Alps, were evaluated. Statistical analysis of 46 years of historical data showed that floods are best modelled by the general...

Nitrogen and phosphorus entering waterways from diffuse agricultural sources is a major problem in New Zealand and internationally.

This study evaluates the effects of floods and their hydraulic characteristics on invasive vegetation in the Ahuriri River floodplain, a braided gravel-bed river in the eastern high country of the South Island, New Zealand. Invasive vegetation alters the natural braiding tendency of rivers such as the Ahuriri and has severe negative impacts on thre...

During the past decade, advances in survey and sensor technology have generated new opportunities to investigate the structure and dynamics of fluvial systems. Key geomatic technologies include the Global Positioning System (GPS), digital photogrammetry, LiDAR, and terrestrial laser scanning (TLS). The application of such has resulted in a profound...

In the semi-arid western U.S., rivers and streams are becoming increasingly stressed and degraded, and wetlands lost, due to human development and associated management policies and actions that are generally ineffective for aquatic resources protection and restoration. There is often a significant disconnect between policy and management with scie...

The Tonle Sap is South East Asia's largest lake and Cambodia's most important fishery. The hydrology of the Tonle Sap is directly linked to water levels of the Mekong River, which will experience major alterations as a response to hydropower development, irrigation, and climate change. This paper proposes a landscape approach to understand the impa...

Caruso, Brian S. and Joshua Haynes, 2011. Biophysical-Regulatory Classification and Profiling of Streams Across Management Units and Ecoregions. Journal of the American Water Resources Association (JAWRA) 00(0):1-22. DOI: 10.1111/j.1752-1688.2010.00522.x Abstract: Aquatic resources management in the United States (U.S.) under Clean Water Act Sectio...

One of the world’s richest manganese (Mn) deposits and largest Mn mining areas lies in the foothills of the Caucasus Mountains, near the city of Chiatura in the Republic of Georgia. This study was an initial evaluation of the effects of Mn mining on water quality in the Chiatura region. Seven river and stream locations (three on the Kvirila River a...

Understanding the connectivity between wetlands and headwater intermittent and ephemeral streams with downstream navigable waters has become a critical focus for U.S. Clean Water Act protection. Recent Supreme Court decisions resulted in a new interpretation and federal agency guidance for how to assess jurisdiction over waters of the U.S. under Se...

Seasonal and spatial variation of metal loads can be significant in mining-impacted mountain watersheds in the western US due to a number of complex physical and biogeochemical factors. Anthropogenic influences, such as seasonal water diversion for municipal supplies, can increase this variability further. This study evaluates the seasonal and spat...

The North Fork of Clear Creek (NFCC), Colorado, is an acid-mine-drainage-impacted stream typical of many mountain surface waters affected by historic metal mining in the western United States. The stream is devoid of fish primarily because of high metal concentrations in the water (e.g., copper and zinc) and has large amounts of settled iron oxyhyd...

Metals pollution in surface waters is a widespread problem in the U.S. and worldwide, particularly in mountainous watersheds in the western U.S. impacted by acid mine drainage from hardrock mines. Metals fate and transport modeling in streams and watersheds is sometimes needed for assessment and restoration of these surface waters. Although subst...

Metals pollution in surface waters from point and non-point sources (NPS) is a widespread problem in the United States and worldwide (Lofts et al., 2007; USEPA, 2007). In the western United States, metals associated with acid mine drainage (AMD) from hardrock mines in mountainous areas impact aquatic ecosystems and human health (USEPA, 1997a; Carus...

Acid mine drainage and metal loads from hardrock mines to surface waters is a significant problem in the western USA and many parts of the world. Mines often occur in mountain environments with fractured bedrock aquifers that serve as pathways for metals transport to streams. This study evaluates impacts from current and potential future groundwate...

  The effects of natural flow restoration on metals fate and transport in the Upper Tenmile Creek Watershed, Montana, were modeled using the Water Quality Analysis Simulation Program developed by the U.S. Environmental Protection Agency (USEPA). This 50-km2 watershed has over 150 historic abandoned mines, including mine waste rock and tailings, as...

This study demonstrates the integration of rehabilitation and flood management planning in a steep, boulder-bedded stream in a coastal urban catchment on the South Island of New Zealand. The Water of Leith, the primary stream flowing through the city of Dunedin, is used as a case study. The catchment is steep, with a short time of concentration and...

In 1991 the New Zealand Department of Conservation implemented Project River Recovery (PRR) to restore braided, gravel-bed riverine and wetland habitats in the Upper Waitaki Basin on the South Island. These are critical habitats for wading and shore birds, including threatened species, but have been degraded by hydroelectric power development. This...

Ecological restoration is increasingly becoming a primary component of broader environmental and water resources management programs throughout the world. The New Zealand Department of Conservation implemented Project River Recovery (PRR) in 1991 to restore unique braided gravel-bed river and wetland habitat in the Upper Waitaki Basin in New Zealan...

Simulation of metals transport was performed to help develop metals total maximum daily loads (TMDLs) and evaluate remediation alternatives in a mountain stream in Montana impacted by hundreds of abandoned hardrock metal mines. These types of watersheds are widespread in Montana and many other areas of the western United States. Impacts from abando...

Simulation of metals transport was performed to help develop metals total maximum daily loads (TMDLs) and evaluate remediation alter-natives in a mountain stream in Montana impacted by hundreds of abandoned hardrock metal mines. These types of,watersheds are widespread in Montana and many other areas of the western United States. Impacts from aband...

The U.S. Environmental Protection Agency (USEPA) Water Quality Analysis Simulation Program (WASP5) was used to model the transport and sediment/water interactions of metals under low flow, steady state conditions in Tenmile Creek, a mountain stream supplying drinking water to the City of Helena, Montana, impacted by numerous abandoned hard rock min...

Water quality simulation was performed to evaluate the effects of restoration alternatives on metals transport in a mountainous watershed in Montana, U.S.A. impacted by hundreds of abandoned hardrock mines. The Water Quality Analysis Simulation Program (WASP5), developed by the U.S. Environmental Protection Agency (U.S. EPA), was used to assist in...

Metals transport modeling was performed to help develop metals total maximum daily loads (TMDLs) and evaluate the effects of restoration alternatives on metals transport in a mountain watershed in Montana impacted by hundreds of abandoned hardrock metal mines. These types of watersheds are widespread in Montana and many other areas of the western U...

The temporal and spatial patterns of summer extreme low flows and effects on stream ecosystems were evaluated throughout the Otago Region of the South Island of New Zealand during a severe drought in 1998–1999. Flows, water quality, and aquatic biology were monitored bimonthly at 12 locations as part of a long-term regional monitoring programme and...

New Zealand is known throughout the world as a “clean and green” country with pristine coastal, mountain, and rural landscapes. In the few urban areas of the country, however, many rivers and streams have been extensively modified through channelization for flood control, impacted by stormwater and nonpoint source pollution, and kept separate from...

Management of agricultural diffuse pollution requires targeting or prioritising critical source areas at various spatial scales within watersheds. This study develops, evaluates and illustrates a risk-based approach for assessment and targeting of source areas at catchment, subarea and individual farm scales. Catchment water quality data are used i...

During severe drought and low flows in the Otago Region of the South Island of New Zealand, increased bacterial contamination of rivers occurred in agricultural/pastoral catchments due to greater stock use of waterways and the lack of dilution and flushing flows. Concentrations and loadings of nitrogen and phosphorus generally decreased due to the...

Spatial and temporal variability of stream total phosphorus (TP) concentrations and loadings was evaluated over a year in a high‐country agricultural catchment. One storm event was also sampled at the inflow to a lake. An upland tributary had the highest median concentration (0.064 mg 1), but the maximum (0.614 mg 1) occurred at the inflow during t...

This study illustrates an integrated watershed-based approach for assessment of phosphorus (P) in the Lake Hayes catchment in the South Island of New Zealand. Spatial and temporal variability of total (TP) and dissolved reactive P (DRP) concentrations and loadings were evaluated at key locations including inflow to, within, and outflow from the lak...

The role of the central government in New Zealand is generally limited to research and policy development, and regional councils are responsible for most monitoring and management of the problem. The role of the federal government in the United States includes research and monitoring, policy development, and regulation. States also have a significa...

Low flows in 21 rivers in the Otago region of the South Island of New Zealand were estimated using several different frequency analysis methods and compared to assist in setting minimum flows for protection of instream uses. Theoretical frequency distributions, including the log-normal, Weibull, and Extreme Value Type 1 distributions, and the Gring...

The effects of landslides on contaminant sources and transport during storms in steep pastoral hill country were evaluated for a small, first-order hillslope in the Lake Tutira catchment, New Zealand. Nitrate (NO3- - N) concentrations were significantly higher in soil water than in subsurface water in the saturated zone, in surface runoff, and in a...

A screening-level assessment of dissolved zinc from inactive and abandoned metal mines in the Cement Creek Basin was performed. The basin is part of the Upper Animas River Basin in the San Juan Mountains of southwestern Colorado. Stream discharge and dissolved zinc concentrations were measured at 49 stations below nonpoint sources including tailing...

This study evaluated the attributes and uncertainty of non-point source pollution data derived from synoptic surveys in a catchment affected by inactive metal mines in order to help to identify and select appropriate methods for data analysis/reporting and information use. Dissolved zinc data from the Upper Animas River Basin, Colorado, USA, were t...

This study evaluated the attributes and uncertainty of non-point source pollution data derived from synoptic surveys in a catchment affected by inactive metal mines in order to help to identify and select appropriate methods for data analysis/reporting and information use. Dissolved zinc data from the Upper Animas River Basin, Colorado, USA, were t...

A screening-level assessment of dissolved zinc from inactive and abandoned metal mines in the Cement Creek Basin was performed. The basin is part of the Upper Animas River Basin in the San Juan Mountains of southwestern Colorado. Stream discharge and dissolved zinc concentrations were measured at 49 stations below nonpoint sources including tailing...

A watershed-based approach for screening-level assessment of nonpoint source pollution from inactive and abandoned metal mines was developed and illustrated. The methodology was designed to use limited stream discharge and chemical data from synoptic surveys to derive key information required for targeting impaired waterbodies and critical source a...

Thesis (Ph. D.)--Colorado State University, 1995. Includes bibliographical references.