Skip to main content
U.S. flag

An official website of the United States government

Matthew Miller

Matt Miller is a Research Hydrologist with the Earth Systems Modeling Branch of the Integrated Modeling and Prediction Division in Boulder, Colorado.

His current research focuses on developing new approaches for interpreting large data sets to quantify the relationships between water quality, hydrology, land use, and climate at watershed, regional, and national scales.  Matt develops and applies modeling tools that improve process understanding of integrated terrestrial-aquatic systems to improve understanding of water availability.  Current projects include projecting the baseflow component of streamflow in the Upper Colorado River Basin, estimating future nutrient loading to estuaries in the southeastern United States, identifying sources of nitrogen to streams in Brazilian watersheds, and using water quality data to better understand groundwater discharge to streams in the Delaware River Basin.

 

Education and Certifications

  • Ph.D., Civil and Environmental Engineering, University of Colorado, Boulder (2008)

  • M.S., Civil and Environmental Engineering, University of Colorado, Boulder (2004)

  • B.S., Zoology, University of Wisconsin, Madison (2000)

Science and Products

link
Mountains and pine trees covered with a thick layer of snow.

Integrated Water Availability Assessments: Upper Colorado River Basin

Integrated Water Availability Assessments examine water supply, use, and availability. Snow from the Upper Colorado River Basin contributes 92% of the natural streamflow to the entire Colorado River Basin. The UCOL IWAAs will improve our understanding of the water budget, status and trends in water quality and ecological conditions, and ecosystem response to changes in climate and human water use.
By
Water Resources
link

Integrated Water Availability Assessments: Upper Colorado River Basin

Integrated Water Availability Assessments examine water supply, use, and availability. Snow from the Upper Colorado River Basin contributes 92% of the natural streamflow to the entire Colorado River Basin. The UCOL IWAAs will improve our understanding of the water budget, status and trends in water quality and ecological conditions, and ecosystem response to changes in climate and human water use.
Learn More
link
Image: Susquehanna River - Conowingo Dam

Targeted management of a small number of catchments may help reduce nitrogen loading to Chesapeake Bay

Largest projected reductions associated with decreasing agricultural fertilizer application
By
Core Science Systems, Chesapeake Bay Activities
link

Targeted management of a small number of catchments may help reduce nitrogen loading to Chesapeake Bay

Largest projected reductions associated with decreasing agricultural fertilizer application
Learn More
link
Salt Wash in the San Rafael Swell with white surface salts

Salinity

Studies of Sources and Transport of Dissolved Solids (Salt) in the Colorado River Basin using the Spatially Referenced Regressions on Watershed Attributes (SPARROW) Model The Upper Colorado River Basin (UCRB) encompasses about 112,000 mi2 and discharges more than 6 million tons of dissolved solids (salt) annually to the lower Colorado River Basin. It has been estimated that between 32 and 45...
By
Utah Water Science Center
link

Salinity

Studies of Sources and Transport of Dissolved Solids (Salt) in the Colorado River Basin using the Spatially Referenced Regressions on Watershed Attributes (SPARROW) Model The Upper Colorado River Basin (UCRB) encompasses about 112,000 mi2 and discharges more than 6 million tons of dissolved solids (salt) annually to the lower Colorado River Basin. It has been estimated that between 32 and 45...
Learn More
link
Colored map showing Colorado River Basin watersheds

Baseflow

The Colorado River has been identified as the most overallocated river in the world. Considering predicted future imbalances between water supply and demand and the growing recognition that base flow (a proxy for groundwater discharge to streams) is critical for sustaining flow in streams and rivers, there is a need to develop methods to better quantify present-day base flow across large regions...
By
Utah Water Science Center
link

Baseflow

The Colorado River has been identified as the most overallocated river in the world. Considering predicted future imbalances between water supply and demand and the growing recognition that base flow (a proxy for groundwater discharge to streams) is critical for sustaining flow in streams and rivers, there is a need to develop methods to better quantify present-day base flow across large regions...
Learn More
link
Locations of USGS streamgages in the Potomac River, Smith Creek, and Difficult Run Basins in the Chesapeake Bay watershed.

High-frequency nitrate-concentration data

High-frequency nitrate-concentration data can be used to inform the development of best management practices to reduce nitrogen loading to Chesapeake Bay. Although nitrogen loads entering Chesapeake Bay have decreased in recent decades, they exceed levels that are compatible with a healthy ecosystem as a result of urbanization, agriculture, and other human activities in the bay watershed, and...
By
Chesapeake Bay Activities
link

High-frequency nitrate-concentration data

High-frequency nitrate-concentration data can be used to inform the development of best management practices to reduce nitrogen loading to Chesapeake Bay. Although nitrogen loads entering Chesapeake Bay have decreased in recent decades, they exceed levels that are compatible with a healthy ecosystem as a result of urbanization, agriculture, and other human activities in the bay watershed, and...
Learn More

SPARROW model input datasets and predictions of total dissolved loads in streams of the Upper Colorado River Basin watershed

This data release contains bootstrap values of mean-annual total dissolved solids (TDS) loads predicted by a SPARROW model for individual stream reaches in the Upper Colorado River Basin watershed in the predict.txt file. Also included are the input variables required to execute the model, including dissolved solids sources, landscape characteristics, and calibration data from water quality monito

Mean seasonal time-step estimates of daily streamflow and daily baseflow, and loads of total nitrogen, total phosphorus, and total suspended solids at surface-water stations in the southeastern United States, 2001-14

This metadata record describes mean seasonal time-step estimates of daily streamflow and daily baseflow, and total and baseflow estimates of loads of total nitrogen, total phosphorus, and total suspended solids at surface-water stations in the southeastern United States for the period 2001-14. Streamflow and load estimates described in this data release were obtained using the Fluxmaster approach

Monthly estimates of natural baseflow for 15,866 stream reaches, defined by the National Hydrography Dataset Plus Version 2.0 (NHDPlusV2), in the Delaware River Basin for the period 1950-2015

This metadata record describes monthly estimates of natural baseflow for 15,866 stream reaches, defined by the National Hydrography Dataset Plus Version 2.0 (NHDPlusV2), in the Delaware River Basin for the period 1950-2015. A statistical machine learning technique - random forest modeling (Liaw and Wiener, 2018; R Core Team, 2020) - was applied to estimate natural flows using about 150 potential p

Daily-timestep and monthly-timestep estimates of baseflow at 49 reference stream gages located within 25 miles of the Delaware River basin watershed boundary for the years 1950 through 2015

This USGS data release contains daily-timestep and monthly-timestep estimates of baseflow at 49 reference stream gages located within 25 miles of the Delaware River basin watershed boundary. Estimates are provided for the available period of record of streamflow data at each site between 1950 and 2015. A two-parameter recursive digital filter was used to estimate baseflow at the selected stream ga
By
New Jersey Water Science Center

Natural Monthly Flow Estimates for the Conterminous United States, 1950-2015

This metadata record describes monthly estimates of natural stream flows for greater than 2.5 million stream reaches, defined by the National Hydrography Dataset (NHD) Version 2.0, in the conterminous United States for the period 1950-2015. A statistical machine learning technique - random forest modeling - was applied to estimate natural flows using 200 potential predictor variables. The dataset
By
National Water Quality Program
Map showing the IWAAs and NGWOS study areas in the Upper Colorado River Basin
link
Photo of the Colorado River near Moab, Utah
link
Filter Total Items: 41

A review of current capabilities and science gaps in water supply data, modeling, and trends for water availability assessments in the Upper Colorado River Basin

The Colorado River is a critical water resource in the southwestern United States, supplying drinking water for 40 million people in the region and water for irrigation of 2.2 million hectares of land. Extended drought in the Upper Colorado River Basin (UCOL) and the prospect of a warmer climate in the future pose water availability challenges for those charged with managing the river. Limited wat
By
Ecosystems, Water Resources, Arizona Water Science Center, Southwest Biological Science Center, Utah Water Science Center

Nitrogen in the Chesapeake Bay watershed—A century of change, 1950–2050

ForewordSustaining the quality of the Nation’s water resources and the health of our diverse ecosystems depends on the availability of sound water-resources data and information to develop effective, science-based policies. Effective management of water resources also brings more certainty and efficiency to important economic sectors. Taken together, these actions lead to immediate and long-term e
By
Water Resources, Chesapeake Bay Activities, Maryland-Delaware-D.C. Water Science Center, New York Water Science Center, Pennsylvania Water Science Center, South Atlantic Water Science Center (SAWSC), Utah Water Science Center, Virginia and West Virginia Water Science Center

How will baseflow respond to climate change in the Upper Colorado River Basin?

Baseflow is critical to sustaining streamflow in the Upper Colorado River Basin. Therefore, effective water resources management requires estimates of baseflow response to climatic changes. This study provides the first estimates of projected baseflow changes from historical (1984 – 2012) to thirty-year periods centered around 2030, 2050, and 2080 under warm/wet, median, and hot/dry climatic condi
By
Water Resources, Climate Research and Development Program, Geosciences and Environmental Change Science Center, Utah Water Science Center

Influence of redox gradients on nitrate transport from the landscape to groundwater and streams

Increases in nitrogen applications to the land surface since the 1950s have led to a cascade of negative environmental impacts, including degradation of drinking water supplies, nutrient enrichment of aquatic ecosystems and contributions to global climate change. In this study, groundwater, streambed porewater, and stream sampling were used to establish trends in nitrate concentrations and how red
By
Water Resources, Colorado Water Science Center, Oregon Water Science Center

Ungaged inflow and loss patterns in urban and agricultural sub‐reaches of the Logan River Observatory

Streams in semi‐arid urban and agricultural environments are often heavily diverted for anthropogenic purposes. However, they simultaneously receive substantial inflows from a variety of ungaged sources including stormwater returns, tile drainage, and irrigation runoff that help sustain flow during dry periods. Due to the inability to identify sources or directly gage many of these inflows, there
By
Water Resources

Changing climate drives future streamflow declines and challenges in meeting water demand across the southwestern United States

Society and the environment in the arid southwestern United States depend on reliable water availability, yet current water use outpaces supply. Water demand is projected to grow in the future and climate change is expected to reduce supply. To adapt, water managers need robust estimates of future regional water supply to support management decisions. To address this need, we estimate future strea
By
Water Resources, Climate Research and Development Program, Land Change Science Program, Geosciences and Environmental Change Science Center, Utah Water Science Center

Temporal and spatial variations in river specific conductivity: Implications for understanding sources of river water and hydrograph separations

Specific conductivity (SC) is commonly used to estimate the proportion of baseflow (i.e., waters from within catchments such as groundwater, interflow, or bank return flows) contributing to rivers. Reach-scale SC comparisons are also useful for identifying where multiple water stores contribute to baseflow. Daily SC values of adjacent gauges in Australian (the Barwon, Glenelg, and Campaspe Rivers)
By
Water Resources

Application of the RSPARROW modeling tool to estimate total nitrogen sources to streams and evaluate source reduction management scenarios in the Grande River Basin, Brazil

Large-domain hydrological models are increasingly needed to support water-resource assessment and management in large river basins. Here, we describe results for the first Brazilian application of the SPAtially Referenced Regression On Watershed attributes (SPARROW) model using a new open-source modeling and interactive decision support system tool (RSPARROW) to quantify the origin, flux, and fate
By
Water Resources

Relating hydroclimatic change to streamflow, baseflow, and hydrologic partitioning in the Upper Rio Grande Basin, 1980 to 2015

Understanding how changing climatic conditions affect streamflow volume and timing is critical for effective water management. In the Rio Grande Basin of the southwest U.S., decreasing snowpack, increasing minimum temperatures, and decreasing streamflow have been observed in recent decades, but the effects of hydroclimatic changes on baseflow, or groundwater discharge to streams, have not been inv
By
Water Resources, Colorado Water Science Center, New Mexico Water Science Center, Utah Water Science Center

Response of nitrogen loading to the Chesapeake Bay to source reduction and land use change scenarios: A SPARROW‐informed analysis

In response to concerns regarding the health of streams and receiving waters, the United States Environmental Protection Agency established a total maximum daily load for nitrogen in the Chesapeake Bay watershed for which practices must be in place by 2025 resulting in an expected 25% reduction in load from 2009 levels. The response of total nitrogen (TN) loads delivered to the Bay to nine source
By
Water Resources, Chesapeake Bay Activities, Maryland-Delaware-D.C. Water Science Center, Pennsylvania Water Science Center

Salinity yield modeling of the Upper Colorado River Basin using 30-meter resolution soil maps and random forests

Salinity loading in the Upper Colorado River Basin (UCRB) costs local economies upwards of $300 million US dollars annually. Salinity source models have generally included coarse spatial data to represent non‐agriculture sources. We developed new predictive soil property and cover maps at 30 m resolution to improve source representation in salinity modeling. Salinity loading erosion risk indices w
By
Ecosystems, Water Resources, Climate Research and Development Program, Land Change Science Program, California Water Science Center, Southwest Biological Science Center, Utah Water Science Center

Monitoring the Riverine Pulse: Applying high-frequency nitrate data to advance integrative understanding of biogeochemical and hydrological processes

Widespread deployment of sensors that measure river nitrate (NO3-) concentrations has led to many recent publications in water resources journals including review papers focused on data quality assurance, improved load calculations, and better nutrient management. The principal objective of this paper is to review and synthesize studies of high-frequency NO3- data that have aimed to improve unders
By
Water Resources

Non-USGS Publications**

Miller, M.P., D.M. McKnight, R. M. Cory, M. Williams, R. L. Runkel (2006) Hyporheic exchange and fulvic acid redox reactions in an alpine stream/wetland ecosystem, Colorado Front Range. Environmental Science and Technology, 40, 5943-5949
Gardner, E.M, D.M. McKnight, W.M. Lewis, M.P. Miller (2008) Effects of nutrient enrichment on phytoplankton in an alpine lake, Colorado, U.S.A. Arctic, Antarctic, and Alpine Research, 40(1), 55-64.
Tipping, E., H.T. Corbishley, J.F. Koprivnjak, D.J. Lapworth, M.P. Miller, C.D. Vincent, J. Hamilton Taylor (2009) Quantification of natural DOM from UV absorption at two wavelengths. Environmental Chemistry, 6, 472-476.
Miller, M.P., D.M. McKnight, J. Cullis, A. Greene, K. Vietti, D. Liptzin (2009) Factors controlling streambed coverage of Didymosphenia geminata in two regulated streams in the Colorado Front Range. Hydrobiologia, 630, 207-218.
Miller, M.P., D.M. McKnight, S.C. Chapra, M.W. Williams (2009) A model of degradation and production of three pools of dissolved organic matter in an alpine lake. Limnology and Oceanography, 54(6), 2213-2227.
Miller, M.P., D.M. McKnight, S.C. Chapra (2009) Production of microbially derived fulvic acid from photolysis of quinone-containing extracellular products of phytoplankton. Aquatic Sciences, 71, 170-178.
Flanagan, C.M., D.M. McKnight, D. Liptzin, M.W. Williams, M.P. Miller (2009) Response of the phytoplankton community in an alpine lake to drought conditions: Colorado Rocky Mountain Front Range, U.S.A. Arctic, Antarctic, and Alpine Research, 41(2), 191-203.
Fellman, J.B., M.P. Miller, R.M. Cory, D.V. D’Amore, D. White (2009) Characterizing dissolved organic matter using PARAFAC modeling of fluorescence spectroscopy: A comparison of two models. Environmental Science and Technology, 43, 6228-6234.
Mladenov, N., Y. Zheng, M.P. Miller, D.R. Nemergut, T. Legg, B. Simone, C. Hageman, M. M. Rahman, K. M. Ahmed, D.M. McKnight (2010) Dissolved organic matter sources and consequences for iron and arsenic mobilization in Bangladesh aquifers. Environmental Science and Technology, 44, 123-128.
Miller, M.P., B.E. Simone, D.M. McKnight, R.M. Cory, M.W. Williams, E.W. Boyer (2010) New light on a dark subject: Comment. Aquatic Sciences, 72: 269-275.
Miller, M.P., D.M. McKnight (2010) Comparison of seasonal changes in fluorescent dissolved organic matter among aquatic lake and stream sites in the Green Lakes Valley. Journal of Geophysical Research-Biogeosciences, 115, GOOF12, doi:10.1029/2009JG000985.
Cory, R.M., M.P. Miller, D.M. McKnight, J. Guerard, P. Miller (2010) Effect of instrument-specific response on the analysis of fulvic acid fluorescence spectra. Limnology and Oceanography Methods, 8, 67-78.
Brasher, A.M.D., C.M. Albano, R.N. Close, Q.H. Cannon, and M.P. Miller (2010) Macroinvertebrate communities and habitat characteristics in the northern and southern Colorado Plateau networks: Natural Resources Technical Report, NPS/NCPN/NRTR-2010/320, 107pp.
Brasher, A.M.D., T. Jones, A. Farahi, M.P. Miller, K. Kozar (2011) Pacific Islands Stream Monitoring Protocol: Fish, Shrimp, Snails, and Habitat Characterization. Natural Resources Technical Report, NPS/PACN/NRR-2011/468, 357pp.
Gabor, R., A. Baker, D.M. McKnight, M.P. Miller (2014) Fluorescence indices and their interpretation. In Coble, P.G, Lead, J., Baker, A., Reynolds, D.M, and Spencer, R.G.M., eds., Aquatic Organic Matter Fluorescence Cambridge University Press.
Georgek, J.L., D.K. Solomon, V.M. Heilweil, M.P. Miller (2018) Using tracer-derived groundwater transit times to assess storage within a high-elevation watershed of the Upper Colorado River Basin. Hydrogeol. J., 26, 467-480, doi:10.1007/s10040-017-1655-4.
Bowman, W.D., D.R. Nemergut, D.M. McKnight, M.P. Miller, M.W. Williams (2014) A slide down a slippery slope-alpine ecosystem responses to nitrogen deposition. Plant Ecology and Diversity, 8, 727-738, doi:10.1080/17550874.2014.984786

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

link

Targeted management of a small number of catchments may help reduce nitrogen loading to Chesapeake Bay

A new USGS study uses the SPARROW (SPAtially Referenced Regression On Watershed attributes) model to assess how nitrogen loading to the Chesapeake Bay...

Read Article

Science and Products