Algae study to continue

RBC | Members of the White River Algae Technical Advisory Group (TAG), met Feb. 13 to discuss the 2019 plans to ascertain what is driving the algae growth in the White River to improve the overall health of the watershed. Callie Hendrickson, executive director of the White River and Douglas Creek Conservation Districts facilitated the meeting.

USGS provided a review of 2018 studies and planned 2019 activities. Ken Leib, Western Colorado Office Chief, stated their goal is to document and understand benthic algal occurrence, characteristics and controls at multiple locations within the White River (WR) study area and described the study design and approach. Cory Williams, Western Colorado Studies Chief, reviewed the historical analysis, water quality trends, algae sampling and isotope sampling. Key takeaways are as follows. Historical streamflow analysis showed a decreasing trend in flow patterns since 1900 while available high-resolution water temperature data indicates increasing daily mean temperatures during May-September between two more recent time periods (1979-84 and 2007-17). Little to no change has been shown in the mean, annual concentration of kjeldahl nitrogen while total phosphorous showed a substantial increase in concentration and flux between 1999 and 2017. Concentrations in phosphorous increased during snowmelt-runoff (high flow) and decrease during fall and winter months. Several types of algae were present at each study site and Cladophora was found at all 19 USGS study sites. Water samples were collected and analyzed for nitrate concentrations at six locations but, concentrations were too low for isotope analysis. Isotopic analysis is an aspect of the study intended to aid in identification of sources of nitrate in the watershed. Sampling and nitrate analysis are ongoing and USGS is exploring alternative sampling approaches to meet target concentration ranges. Historical analysis and literature review, physical and chemical characterization/data collection, algae sampling and isotope sampling will all be continued in 2019.

Tyler Adams, project manager, and Susan Nall, section supervisor, with the Army Corps of Engineers (ACE) reviewed permitted activity in the recent past. They described their regulatory authorities and explained how to know when a project is regulated and when it may qualify for exemptions. Available permits vary from Nation Wide Permits (NWP) to Regional General Permits (RGP) to Individual Permits (IP). Permitting history in the Upper White River total 53 permits (NWPs=38, RGPs=14, IP=1), about 866,939 acres, from 2008-2018.

Matt Weaver, 5 Rivers Inc. gave a presentation on a local project proposal that is currently in the application process with the ACE. The proposal is to enhance fish habitat in the White River. The plan is to create 18 pools in which Weaver will remove material from the pool area and add it to the bank to leave everything functioning as a pool-bar sequence. Weaver and the landowners are communicating with the Colorado Parks and Wildlife to avoid disrupting crucial times such as spawning season, etc. One USGS study site is encompassed in the project area. The landowners/managers are willing to work with the TAG and USGS to do their best not to affect the ongoing study.

Several discussion items were identified at the last TAG meeting as potential changes to the USGS 2019 Scope of Work (SOW). Items such as monitoring growth of the algae using pictures, isotopic analysis, water temperature monitoring, taxonomy, capturing the impacts of stream structure changes, water clarity (turbidity) and quantitative mapping were reviewed to make decisions on how the TAG would like to move forward.

After this discussion, the TAG reached a consensus that the White River Conservation District should move forward with the original agreement with USGS to continue the 2019 SOW for the White River Algae project. That SOW includes the workplan elements: Scouring flows and analysis and Pre, peak-, post-algae and water quality sampling events.

See http://www.whiterivercd.com/white-river-algae-working-group.html for Power Point Presentations and meeting notes.

Special to the Herald Times

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