Article

Jonathan O'Donnell - Ecologist

Jon on the Aggie River
Jon O'Donnell is an ecologist for the Arctic Inventory and Monitoring Network. Here he is pictured on the Agashashok River in Noatak National Preserve.

Jonathan O'Donnell
Ecologist
Arctic Inventory and Monitoring Network
240 W 5th Avenue
Anchorage, AK 99501
jaodonnell@nps.gov
907-644-3696

Education
Ph.D. University of Alaska Fairbanks, Biological Sciences, 2010
Dissertation title: The effects of permafrost degradation on soil carbon dynamics in Alaska’s boreal region.
M.S. University of Alaska Fairbanks, Biology, 2005
Thesis: Nitrogen retention in the riparian zone of watersheds underlain by discontinuous permafrost
B.S. Elizabethtown College, Environmental Science, 2000

Professional Experience
2012 – Present Ecologist: National Park Service, Arctic Network
2011 – 2012 Mendenhall Postdoctoral Fellow: U.S. Geological Survey, Boulder, Colorado
2007 – 2010 Research Assistant (Ph.D. Student): Institute of Northern Engineering, University of Alaska Fairbanks
2005 - 2006 Research Technician: Institute of Arctic Biology, University of Alaska Fairbanks
2002 - 2004 Research Assistant (M.S. Student): Institute of Arctic Biology, University of Alaska Fairbanks
2001 Assistant Researcher: USGS Upper Midwest Environmental Science Center, La Crosse, Wisconsin

Awards and Recognition
2021 Director's Award for Natural Resource Research
2018 Farver-Apgar Biology Alumni Award, Department of Biology, Elizabethtown College

Media
What is causing the rusting of northern Alaska streams? Anchorage Daily News, February 10, 2024
Why Are Alaska's Rivers Turning Orange? Scientific American, January 2024
OPINION: The degradation of a wild and scenic river in Alaska's Brooks Range, Anchorage Daily News, November 15, 2022

Projects
The rusting of Arctic rivers: Freshwater ecosystems respond to rapidly uptaking metals. Funded by USGS-NPS Water Quality Partnership Program. (active; FY23-25)

Collaborative research: Linking permafrost soil inundation to carbon and mercury uptake in aquatic food webs of the Arctic. Funded by National Science Foundation, Arctic Natural Sciences (active; 2022-2025).

Tracing mercury through lake food webs in Alaska’s national parks. Funded by USGS NRPP (active; FY20-23).

Beaver range expansion in the Arctic: implications for water quality, aquatic ecosystems, and subsistence fisheries. Funded by the USGS Changing Arctic Ecosystems Initiative (active; FY20-24)

Development, optimization, and application of molecular tools for assessing the range expansion of Cryptosporidium and Giardia in Arctic Alaska relative to climate change. Funded by the USGS Changing Arctic Ecosystems Initiative (active; FY20-24)

Collaborative research: Sea-level rise, coastal wetland expansion, and proglacial lake contributions to abrupt increases in northern atmospheric methane during the last deglaciation. Funded by the National Science Foundation, Paleo Perspectives on Climate Change (active; 2019-2022)

Collaborative research: Constraining the fate and function of permafrost nutrients with direct multi-scale observations: Stream networks as indicators of watershed processes. Funded by the National Science Foundation, Arctic Natural Sciences Program (active; 2019-2022).

Beaver range expansion into arctic tundra: Quantifying effects on stream water quality in Alaska’s arctic national parks. Funded by USGS-NPS Water Quality Partnership Program. (completed; FY19-21)

Testing the ‘standstill hypothesis” versus the ‘Arctic tundra fire hypothesis’ using the longest known sedimentary records from Seward Peninsula, Alaska. Funded by the National Park Service Shared Beringia Heritage Program. (completed; FY18-20)

Resilient landscapes and fire regimes: Meaning, metrics, and management. Funded by the Joint Fire Sciences Program (completed; FY16-18).

Hydro-ecological responses to permafrost degradation in Arctic streams Funded by the USGS Changing Arctic Ecosystems Initiative (completed; FY15-19)

Publications
Shogren, A. J., J. P. Zarnetske, B. W. Abbott, A. L. Grose, A. F. Rec, J. Nipko, C. Song, J. A. O’Donnell, and W. B. Bowden. 2024. Hydrology controls dissolved organic carbon and nitrogen export and post-storm recovery in two Arctic headwaters. JGR Biogeosciences 129(2): e2023JG007583.

Shannon, K. C., N. R. Christman, B. C. Crump, M. P. Carey, J. Koch, L. L. Lapham, J. A. O'Donnell, B. A. Poulin, K. D. Tape, J. A. Clark, and F. S. Colwell. 2023. Comparing sediment microbial communities of Arctic beaver ponds ato tundra lakes and streams. JGR Biogeosciences 128(8): e2023JG007408.

Blaskey, D., J. C. Koch, M. N. Gooseff, A. J. Newman, Y. Cheng, J. A. O'Donnell, and K. N. Musselman. 2023. Increasing Alaskan river discharge during the cold season is driven by recent warming. Environmental Research Letters 18(2): 024042.

Clark, J. A., K. D. Tape, L. Baskaran, C. Elder, C. Miller, K. Miner, J. A. O'Donnell, and B. M. Jones. 2023. Do beaver ponds increase methane emissions along Arctic tundra streams? Environmental Research Letters 18: 075004.

O’Donnell, J., M. Carey, B. Poulin, K. Tape, and J. Koch. 2022. How Beavers Are Changing Arctic Landscapes and Earth’s Climate. Frontiers for Young Minds 10:719051.

Koch, J. C. Y. Sjoberg, J. O’Donnell, M. Carey, P. F. Sullivan and A. Terskaia. 2022. Sensitivity of headwater streamflow to thawing permafrost and vegetation change in a warming Arctic. Environmental Research Letters.

Shogren, A. J., J. P. Zarnetske, B. W. Abbott, S. Bratsman, B. Brown, M. P. Carey, R. Fulweber, H. E. Greaves, E. Haines, F. Iannucci, J. C. Koch, A. Medvedeff, J. A. O’Donnell, L. Patch, B. A. Poulin T. J. Williamson, and W. B. Bowden. 2022. Multi-year, spatially extensive, watershed-scale synoptic stream chemistry and water quality conditions for six permafrost-underlain Arctic watersheds. Earth Systems Science Data 14:95-116.

Olefeldt, D., M. Hovemyr, M. A. Kuhn, D. Bastviken, T. J. Bohn, … J. A. O’Donnell, …, et al. 2021. The boreal-Arctic wetland and lake dataset (BAWLD). Earth System Science Data 13(11): 5127-5149.

Vachula, R. S., K. J. Wang, J. A. O’Donnell, and Y. Huang. 2021. New approaches to study interactions among climate, environment, and humans in Arctic Alaska. Alaska Park Science 20(1): 2-9.

Abbott, B. W., A. V. Rocha, A. Shogren, J. P. Zarnetske, F. Iannucci, W. B. Bowden, S. P. Bratsman, L. Patch, R. Watts, R. Fulweber, R. J. Frei, A. M. Huebner, S. M. Ludwig, G. T. Carling, and J. A. O’Donnell. 2021. Tundra wildfire triggers sustained lateral nutrient loss in Alaskan Arctic. Global Change Biology

Loisel, J., A. V. Gallego-Sala, M. J. Amesbury, ... J. A. O'Donnell, ... et al. 2021. Expert assessment of future vulnerability of the global peatland carbon sink. Nature Climate Change 11: 70-77.

Sjöberg, Y., A. Jan, S. L. Painter, E. T. Coon, M. P. Carey, J. A. O'Donnell, and J. C. Koch. 2021. Permafrost promotes shallow groundwater flow and warmer headwater streams. Water Resources Research 57(2): e2020WR027463.

Wologo, E., S. Shakil, S. Zolkos, S. Textor, S. Ewing, … J. A. O’Donnell, et al. 2020. Stream dissolved organic matter in permafrost regions shows surprising compositional similarities but negative priming and nutrient effects. Global Biogeochemical Cycles: e2020GB006719.

Sulman, B. N., J. Harden, Y. He, C. Treat, C. Koven, … J. A. O’Donnell, … et al. 2020. Land use and land cover affect the depth distribution of soil carbon: Insights from a large database of soil profiles. Frontiers in Environmental Science.

O’Donnell, T. Douglas, A. Barker, and L. Guo. 2020. Changing biogeochemical cycles of organic carbon, nitrogen, phosphorus, and trace elements in Arctic Rivers. pages 315-348 in D. Yang and D. L. Kane, eds, Arctic Hydrology, Permafrost and Ecosystems. Springer Nature, Switzerland.

Kropp, H., M. M. Loranty, S. M. Natali, A. L. Kholodov, A. V. Rocha, … J. A. O’Donnell … et al. 2020. Shallow soils are warmer under trees and tall shrubs across Arctic and Boreal ecosystems. Environmental Research Letters.

Estop-Aragonés, C., D. Olefeldt, B. W. Abbott, J. P. Chanton, C. I. Czimczik, … J. A. O’Donnell, … et al. 2020. Assessing the potential for mobilization of old soil carbon after permafrost thaw: A synthesis of 14C measurements from the northern permafrost region. Global Biogeochemical Cycles 34(9): e2020GB006672.

O’Donnell, J. A., M. P. Carey, J. Koch, and C. E. Zimmerman. 2020. Permafrost carbon in stream food webs of Arctic Alaska. Alaska Park Science 19(1): 76-79.

Wang, K. J., J. A. O'Donnell, W. M. Longo, L. Amaral-Zettler, G. Li, Y. Yao, and Y. Huang. 2019. Group I alkenones and Isochrysidales in the world's largest maar lakes and their potential paleoclimate applications. Organic Geochemistry

O'Donnell, J. A., M. P Carey, J. C. Koch, X. Xu, B. A. Poulin, J. Walker, and C. E. Zimmerman. 2019. Permafrost hydrology drives the assimilation of old carbon by stream food webs in the Arctic. Ecosystems

Larsen A, O’Donnell JA, Swanson DK, Schmidt JS. 2017. Physical and chemical characteristics of lakes across heterogeneous landscapes in Arctic and Subarctic Alaska. Journal of Geophysical Research Biogeosciences 122: 989-1008, doi:10.1002/2016JG003729.

O’Donnell JA, Aiken GR, Swanson DK, Panda S, Baltensperger A, and Butler KD. 2016. Dissolved organic matter composition of Arctic rivers: linking permafrost and parent material to riverine carbon. Global Biogeochemical Cycles, doi:10.1002/2016GB005482.

O’Donnell JA, Aiken GR, Butler KD, Guillemette F, Podgorski DC, and Spencer RGM. 2016. DOM composition and transformation in boreal forest soils: the effects of temperature and organic-horizon decomposition state. Journal of Geophysical Research Biogeosciences, 121, 2727-2744, doi:10.1002/2016JG003431.

Jones, MC, Harden JW, O’Donnell JA, Manies KL, Jorgenson MT, and Ewing SA. 2016. Rapid carbon losses and slow recovery following permafrost thaw inds boreal peatlands. Global Change Biology, doi:10.1111/gcb.13403.

Schädel C, Bader MKF, Schuur EAG, Bracho R, Capek P, De-Baets S, Diakova K, Ernakovich J, Hartley IP, Iverson C, Kane E, Knoblauch C, Lupascu M, Natali S, Norby RJ, O’Donnell JA, Chowdhury TR, Santruckova H, Shaver G, Sloan VL, Treat C, Turetsky MR, Waldrop M, and Wickland KP. 2016. Potential carbon emissions dominated by carbon dioxide from thawed permafrost soils. Nature Climate Change, doi:10.1038/nclimate3054

Jiang Y, Zhuang Q, Sitch S, O’Donnell JA, Sokolov A, Kicklighter D, Melillo J. 2016. Importance of soil thermal regime in terrestrial ecosystem carbon dynamics in the circumpolar north. Global and Planetary Change 142, 28-40, doi:10.1016/j.gloplacha.2016.04.011.

Treat C, Jones M, Camill P, Garneau M, Galego-Sala A, Harden J, Hugelius G, Klein E, Kokfelt U, Kuhry P, Loisel J, Mathigssen P, O’Donnell JA, Oksanen P, Ronkainen T, Sannel B, Talbot J, Tarnocai C, Valiranta M. 2016. Effects of permafrost aggradation on peat properties as determined from a pan-arctic synthesis of plant macrofossils. Journal of Geophysical Research Biogeosciences, doi:10.1002/2015JG003061.

Tape KD, Christie K, Carroll G, and O’Donnell JA. 2016. Novel wildlife in the Arctic: the influence of changing riparian ecosystems and shrub habitat expansion on snowshoe hares. Global Change Biology, 22, 208-219, doi:10.1111/gcb.13058.

Ewing SA, O’Donnell JA, Aiken GR, Butler KD, Butman D, Windham-Myers L, and Kanevskiy MZ. 2015. Long-term anoxia and release of ancient, labile carbon upon thaw of Pleistocene permafrost. Geophysical Research Letters, 42, 10730-10738, doi:10.1002/2015GL0066296.

Jiang Y, Rocha AV, O’Donnell JA, Drysdale JA, Rastetter EB, Shaver GR, and Zhuang Q. 2015. Contrasting soil thermal responses to fire in Alaskan tundra and boreal forest. Journal of Geophysical Research-Earth Surface, 120, 363-378, doi:10.1002/2014JF003180.

Ewing SA, Paces JB, O’Donnell JA, Jorgenson MT, Kanevskiy MZ, Aiken GR, Shur Y, Harden JW, Striegl R. 2015. Uranium isotopes and dissolved organic carbon in loess permafrost: modeling the age of ancient ice. Geochimica et Comochimica Acta, doi:10.1016/j.gca.2014.11.008.

O’Donnell JA, Aiken GR, Walvoord MA, Raymond PA, Butler KD, Dornblaser MM, and Heckman K. 2014. Using dissolved organic matter composition and age to detect permafrost thaw in boreal streams of interior Alaska. Journal of Geophysical Research – Biogeosciences, 119, doi:10.1002/2014JG002695.

Hugelius G, Strauss J, Zubrzycki S, Harden JW, Schuur EAG, Ping CL, Schirrmeister L, Grosse G, Michaelson GJ, Koven C, O’Donnell JA, Elberling B, Mishra U, Camill P, Yu Z, Palmtag J, Kuhry P. 2014. Estimated stocks of circumpolar permafrost carbon with quantified uncertainty ranges and identified data gaps. Biogeosciences, 11: 6573-6593, doi:10.5194/bg-11-6573-2014.

Euskirchen E, Turetsky MR, O’Donnell JA, Danaan R. 2014. Snow, permafrost, ice cover, and climate change. In Handbook of Global Environmental Pollution, Volume 1: Global Environmental Change. Edited by Bill Freedman. New York: Springer, pp. 199-214. ISBN 978-94-007-5785-1

Kanevskiy M, Jorgenson MT, Shur Y, O’Donnell JA, Harden JW, Zhuang Q, and Fortier D. 2014. Cryostratigraphy and permafrost evolution in lacustrine lowlands of West-Central Alaska. Permafrost and Periglacial Processes, 25: 14-34. doi:10.1002/ppp.1800.

Hugelius, G, JG Bockheim, P Camill, B Elberling, G Grosse, JW Harden, K Johnson, T Jorgenson, CD Koven, P Kuhry, G Michaelson, U Mishra, J Palmtag, C-L Ping, JA O’Donnell, L Schirrmeister, EAG Schuur, Y Sheng, LC Smith, J Strauss, and Z Yu. 2013. A new data set for estimating organic carbon storage to 3 m depth in soils of the northern circumpolar permafrost region. Earth Systems Science Data 5: 393-402, doi:10.5194/essd-5-393-2013.

Jorgenson MT, Harden JW, Kanevskiy MZ, O’Donnell JA, Wickland KP, Ewing SA, Manies KL, Zhuang Q, Shur Y, Striegl R, and Koch J. 2013. Reorganization of vegetation, hydrology, and soil carbon changes after permafrost degradation across heterogenous boreal landscapes. Environmental Research Letters, 8, 035017, doi:10.1088/1748-9326/83/035017.

Schuur EAG, Abbott BW, Bowden WB, Brovkin V, Camill P, Canadell JP, Chanton JP, Chapin FS III, Christensen TR, Ciais P, Crill PM, Crosby BT, Czimczik CI, Grosse G, Harden J, Hayes DJ, Hugelius G, Jastrow JD, Jones JB, Kleinen T, Koven CD, Krinner G, Kuhry P, Lawrence DM, McGuire AD, Natali SM, O’Donnell JA, Ping CL, Riley WJ, Rinke A, Romanovsky VE, Sannel ABK, Schädel C, Schaefer K, Sky J, Subin ZM, Tarnocai C, Turetsky MR, Waldrop M, Walter-Anthony KM, Wickland KP, Wilson CJ, and Zimov SA. 2013. Expert assessment of vulnerability of permafrost carbon to climate change. Climatic Change, doi:10.1007/s10584-013-0730-7.

O’Donnell JA, Aiken GR, Walvoord MA, Butler KD. 2012. Dissolved organic matter composition of winter stream flow in the Yukon River basin: implications of permafrost thaw and increased groundwater discharge. Global Biogeochemical Cycles, 26, GB0E06, doi:10.1029/2012GB004341.

Harden JW, Koven CD, Ping CL, Hugelius G, McGuire AD, Camill P, Jorgenson MT, Kuhry P, Michaelson GJ, O’Donnell JA, Schuur EAG, Tarnocai C, Johnson K, Grosse G. 2012. Field information links permafrost carbon to physical vulnerabilities of thawing. Geophysical Research Letters, doi:10.1029/2012GL051958.

Jiang Y, Zhuang Q, O’Donnell JA. 2012. Modeling thermal dynamics of active layer soils and near-surface permafrost using a fully coupled water and heat transport model. Journal of Geophysical Research-Atmospheres 117, D11110, doi:10.1029/2012JD017512.

Kanevskiy M, Shur Y, Connor B, Dillon M, Stephani E, O’Donnell JA. 2012. Study of the ice-rich syngenetic permafrost for road construction (interior Alaska). In: Proceedings of the Tenth International Conference on Permafrost, June 25-29, 2012 Salekhard, Russia. The Northern Publisher, Salekhard, Russia. Vol. 1: International contributions, Hinkel KM (ed): 191-196.

Harden JW, Manies KL, O’Donnell JA, Johnson K, Frolking S, Fan Z. 2012. Spatiotemporal studies of black spruce forest soils and implications for C fate. Journal of Geophysical Research-Biogeosciences 117, G01012, doi:10.1029/2011JG001826.

O’Donnell JA, Jorgenson MT, Harden JW, McGuire AD, Kanevskiy MZ, Wickland KP. 2012. The effects of permafrost thaw on soil hydrologic, thermal and carbon dynamics in an Alaskan peatland. Ecosystems 15: 213-229, doi:10.1007/s10021-011-9504-0.

Johnson KD, Harden JW, McGuire AD, Bliss NB, Bockheim JG, Clark M, Nettleton-Hollingsworth T, Kane ES, Mack M, O’Donnell JA, Ping C-L, Schuur EAG, Turetsky MR, Valentine DW. 2011. Soil carbon distribution in Alaska in relation to soil-forming factors. Geoderma 167-168: 71-84.

Fan Z, Neff JC, Harden JW, Zhang T, Veldhuis H, Czimczik CI, Winston GC, O’Donnell JA. 2011. Water and heat transport in boreal soils: implications for soil response to climate change. Science of the Total Environment 409: 1836-1842.

O’Donnell JA, Harden JW, McGuire AD, Kanevskiy MZ, Jorgenson MT, Xu X. 2011. The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: implications for post-thaw carbon loss. Global Change Biology 17: 1461-1474, doi:10.1111/j.1365-2486.2010.02358.x.

O’Donnell JA, Harden JW, McGuire AD, Romanovsky VE. 2011. Exploring the sensitivity of soil carbon dynamics to climate change, fire disturbance and permafrost thaw in a black spruce ecosystem. Biogeosciences 8: 1367-1382.

Jorgenson MT, Romanovsky VE, Harden JW, Shur Y, O’Donnell JA, Schuur EAG, Kanevskiy M, and Marchenko S. 2010. Resilience and vulnerability of permafrost to climate change. Canadian Journal of Forest Research 40: 1219-1236.

O’Donnell JA, Aiken GR, Kane ES, Jones JB. 2010. Source water controls on DOC character and origin in streams of the Yukon River basin, Alaska. Journal of Geophysical Research – Biogeosciences 115: G03025, doi:10.1029/2009J001153.

O’Donnell JA, Romanovsky VE, Harden JW, McGuire AD. 2009. The effect of soil moisture content on the thermal conductivity of soil organic horizons in black spruce ecosystems of interior Alaska. Soil Science 174: 646-651.


O’Donnell JA, Turetsky MR, Harden JW, Manies KL, Pruett LE, Shetler G, Neff JC. 2009. The interactive effects of fire, soil climate, and moss on CO2 fluxes in black spruce ecosystems of interior Alaska. Ecosystems doi: 10.1007/s1002-1-008-9206-4.

Kane ES, Betts EF, Burgin AJ, Clilverd HM, Crenshaw CL, Fellman JB, Myers-Smith IH, O’Donnell JA, Sobota DJ, Van Verseveld WJ, Jones JB. 2008. Precipitation control over nitrogen retention across watersheds: a synthesis of Long-Term Ecological Research. Ecohydrology 1: 105-117.

O’Donnell JA, Jones JB. 2006. Nitrogen retention in the riparian zone of watersheds underlain by discontinuous permafrost. Freshwater Biology 51: 854 – 864.

Bartsch MR, Newton TJ, Allran JW, O’Donnell JA, Richardson WB. 2003. Effects of pore-water ammonia on in situ survival and growth of juvenile mussels (Lampsilis cardium) in the St. Croix Riverway, Wisconsin, USA. Environmental Toxicology and Chemistry 22: 2561-2568.


Newton TJ, Allran JW, O’Donnell JA, Bartsch MR, Richardson WB. 2003. Effects of ammonia on juvenile unionid mussels (Lampsilis cardium) in laboratory sediment toxicity tests. Environmental Toxicology and Chemistry 22: 2554-2560.

O’Donnell JA, and Miller SD. 2017 (in review). Lake communities and ecosystems monitoring protocol for the Arctic Network, Alaska. Natural Resource Report. NPS/ARCN/NRR-2017/XXX. National Park Service. Fort Collins, Colorado.

O’Donnell JA, and Miller SD. 2017 (in review). Stream communities and ecosystems monitoring protocol for the Arctic Network, Alaska. Natural Resource Report. NPS/ARCN/NRR-2017/XXX. National Park Service. Fort Collins, Colorado.

O’Donnell JA, Zimmerman CE, Carey MP, Kock JC. 2017. Potential effects of permafrost thaw on Arctic river ecosystems. Alaska Park Science 16:47-50.

O’Donnell JA, Aiken GR, Butler KD, Douglas TA. 2015. Chemical composition of large lakes in Alaska’s Arctic Network: 2013-2014. Natural Resource Data Series. NPS/ARCN/NRDS – 2015/985. National Park Service, Fort Collins, Colorado.

O’Donnell JA, Aiken GR, Butler KD, Trainor TP, Douglas TA. 2015. Chemical composition of rivers in Alaska’s Arctic Network, 2013-2014. Natural Resource Data Series. NPS/ARCN/NRDS – 2015/809. National Park Service. Fort Collins, Colorado. Published Report-2222958.

O’Donnell JA, Harden JW, Manies KL, Jorgenson MT, Kanevskiy MZ. 2013. Soil data from fire and permafrost-thaw chronosequences in upland Picea mariana stands near Hess Creek and Tok, Alaska. US Geological Survey Open-File Report 2013-1045, p. 22.

O’Donnell JA, Harden JW, Manies KL, Jorgenson MT. 2012. Soil data for a collapse-scar bog chronosequence in Koyukuk Flats National Wildlife Refuge, Alaska. US Geological Survey Open-File Report 2012-1230, p.14.

O’Donnell JA, Harden JW, Manies KL. 2011. Soil physical, chemical, and gas flux characterization from Picea mariana stands near Erickson Creek, Alaska. U.S. Geological Survey Open File Report 2011-1153, p.18.

Shur Y, Kanevskiy M, Dillon M, Stephani E, O’Donnell JA. 2010. Geotechnical investigations for the Dalton Highway innovation project as a case study of the ice-rich syngenetic permafrost. Report # FHWA-AK-RD-10-06, prepared for AK DOT & PF, AUTC assigned project # 207122. Institute of Northern Engineering, University of Alaska Fairbanks.

Newton TJ, Bartsch MR, Allran JW, O’Donnell JA, Richardson WB. 2003. Effects of ammonia on unionid mussels: A threat to their biodiversity in the St. Croix National Scenic Riverway. Technical Report submitted to the National Park Service.

Last updated: April 1, 2024