Southeast Alaska Network freshwater water quality monitoring program: 2017 annual report

Sergeant, Christopher; Johnson, William

Freshwater water quality is an indicator of aquatic and terrestrial ecosystem health and one of the priority Vital Signs in the National Park Service’s Southeast Alaska Network (SEAN), which includes Glacier Bay National Park and Preserve, Klondike Gold Rush National Historical Park, and Sitka National Historical Park. Data collected under this program inform several management-relevant topics: • Monitoring the frequency and magnitude of low dissolved oxygen events (hypoxia) in the Indian River in Sitka • Measuring the natural quality of wilderness lands in Glacier Bay • Describing effects of a changing climate on the physical and chemical properties of park waters • Assessing whether state and federal water quality standards are met This eighth annual report is intended to be a concise data summary and regular product for park staff, managers, superintendents, and other interested parties. All annual reports and data products are publicly available at the SEAN website (http://science.nature.nps.gov/im/units/sean/FQ_Main.aspx), but website structure of NPS Inventory and Monitoring Programs will be changing over the next year and data products will be shifting to the NPS Data Store (https://irma.nps.gov/DataStore/Reference/Profile/2182282). In 2017, hourly water temperature, specific conductance, dissolved oxygen, and pH data were collected in the Salmon River (Glacier Bay) from April 28 through November 1, and in the Indian River (Sitka) from April 21 through November 14. The same parameters plus turbidity were collected in the Taiya River (Klondike Gold Rush) from April 12 through November 9. No observations signaled a change to the fundamental water quality patterns of the three rivers. Daily mean temperature for the Salmon River ranged from 4.0 to 11.0°C (peaking on August 14), while the Indian River ranged from 4.5 to 10.2°C (peaking on August 14, as well). Daily mean temperature for the glacially influenced Taiya River ranged from -0.1 to 6.9°C and peaked on August 18. Taiya River hourly turbidity measurements ranged from 1.0 to 1,045 NTU and were synchronized with high flow events. Patterns in the medians and distributions of specific conductance, dissolved oxygen, and pH were generally similar to previously observed ranges for all three rivers. The critically low dissolved oxygen levels in the Indian River observed during summer 2013 have not been observed in subsequent years.

Southeast Alaska Network freshwater water quality monitoring program: 2017 annual report

Series

Other versions

Collections