Turbid releases from Glen Canyon Dam, Arizona, following rainfall-runoff events of September 2013

Richard A. Wildman; William Vernieu

doi:10.1080/10402381.2017.1293756

Home/Archive/USGS

USGS · 70187972

Turbid releases from Glen Canyon Dam, Arizona, following rainfall-runoff events of September 2013

Richard A. Wildman·William Vernieu

View original source ↗Export metadata ↓

Abstract

Glen Canyon Dam is a large dam on the Colorado River in Arizona. In September 2013, it released turbid water following intense thunderstorms in the surrounding area. Turbidity was >15 nephelometric turbidity units (NTU) for multiple days and >30 NTU at its peak. These unprecedented turbid releases impaired downstream fishing activity and motivated a rapid-response field excursion. At 5 locations upstream from the dam, temperature, specific conductance, dissolved oxygen, chlorophyll a , and turbidity were measured in vertical profiles. Local streamflow and rainfall records were retrieved, and turbidity and specific conductance data in dam releases were evaluated. Profiling was conducted to determine possible sources of turbidity from 3 tributaries nearest the dam, Navajo, Antelope, and Wahweap creeks, which entered Lake Powell as interflows during this study. We discuss 4 key conditions that must have been met for tributaries to influence turbidity of dam releases: tributary flows must have reached the dam, tributary flows must have been laden with sediment, inflow currents must have been near the depth of dam withdrawals, and the settling velocity of particles must have been slow. We isolate 2 key uncertainties that reservoir managers should resolve in future similar studies: the reach of tributary water into the reservoir thalweg and the distribution of particle size of suspended sediment. These uncertainties leave the source of the turbidity ambiguous, although an important role for Wahweap Creek is possible. The unique combination of limnological factors we describe implies that turbid releases at Glen Canyon Dam will continue to be rare.

Explore related subjects

Lake and Reservoir Management Article

Source-reported bounding extent: 36.92958567631005° to 37.00063338417457° latitude; -111.49578094482422° to -111.37184143066406° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Richard A. Wildman, William Vernieu. 2017-03-24. Turbid releases from Glen Canyon Dam, Arizona, following rainfall-runoff events of September 2013. https://doi.org/10.1080/10402381.2017.1293756

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

USGS2025

Water quality-based risk assessment for zebra mussel establishment: A case study of single- and multiple-factor methods in northern temperate lakes

Most previous research has used an individual water quality parameter, such as calcium, to predict likelihood of zebra mussel establishment in lakes; we employed two multiple-factor methods, our own susceptibility index for zebra mussels in lakes (SIZL) and aragonite saturation state, to evaluate the risk of mussel establishment. Thirty sites in Voyageurs National Park (VNP) were sampled in 2023 for water quality conditions, including those that play a key role in mussel survivability. These results were combined with existing data sets to determine which lakes, and which locations within the larger lakes, are at greatest risk for zebra mussel establishment. Results for VNP indicate that physical lake characteristics and water quality conditions (both single- and multiple-factor methods) put the large, interconnected lakes in VNP at greater risk of zebra mussel establishment than the smaller interior lakes. All sampled interior lakes had alkalinity and calcium concentrations below thresholds conducive to zebra mussel establishment, although Mukooda and O’Leary lakes were identified as the most at-risk interior lakes. The area in the large lakes most at risk was Sullivan Bay in Kabetogama Lake, where water quality conditions were found to be conducive to zebra mussel establishment. Results from this study could be used by resource managers to focus additional inspections, decontaminations, and regulations to protect the most at-risk lakes. These multiple-factor methods may be useful in determining the risk of zebra mussel infestation in other water bodies.

Minnesota↗

USGS2025

Geochemical assessment of the suitability of converting a coal-fired power plant reservoir to a drinking-water reservoir

There is an increasing need for additional water storage in the United States, especially in arid regions. Alternatives like decommissioned power plant raw-water reservoirs would be cheaper to use than creating new reservoirs; however, the biogeochemical pollution risk of these reservoirs is not well understood. The San Juan Generating Station power plant and the associated reservoir will be used as a sediment-settling basin to store drinking water. To evaluate whether the reservoir is appropriate for this use, inorganic and organic constituents of concern were measured in reservoir sediment cores, pore water, and reservoir water in 2020. Forty-six percent of sediment arsenic concentrations measured in core subsamples (8 to 12 mg/kg) were slightly above the New Mexico residential cancer threshold for soil of 7.07 mg/kg. One sediment sample contained elevated total barium concentrations (6020 mg/kg). The organic compounds analyzed were either below detection limits or below regulatory thresholds. Reservoir water had one sample with arsenic greater than the drinking water standard (10 µg/L). Overall, the reservoir sediment inorganic and organic analyte concentrations are within acceptable ranges. The few samples that have elevated concentrations are not of a sufficient magnitude that dilution and/or treatment processes would preclude the use of the reservoir for water storage. Our findings show potential for use of former coal power station raw-water reservoirs as drinking-water reservoirs after plant closure.

New Mexico↗

USGS2024

An evaluation of cyanobacterial occurrence and bloom development in Adirondack lakes

Cyanobacterial harmful algal blooms (cyanoHABs) have occurred in many low nutrient (oligotrophic) lakes in the northeastern United States. The Adirondack Park in New York is a large, mountainous region with many low nutrient lakes. There is a gap in understanding regarding whether cyanoHAB reporting data are truly reflective of the susceptibility of lakes to develop bloom conditions. We evaluated lakes with and without documented cyanoHABs for cyanotoxin synthetase gene quantification, phytoplankton community composition, and akinete abundance to identify conditions associated with the observation of cyanoHABs. We analyzed: (1) contributions of cyanobacteria to the overall phytoplankton community; (2) differences in cyanobacterial communities and the presence of cyanotoxin synthetase genes; and (3) lake physical and geomorphological attributes as drivers of differences in cyanobacteria occurrence. Two sample types (water and sediment) were collected from two sample locations (nearshore and open water) in five lakes in 2021. We found cyanobacteria in all lakes and sample locations. Phytoplankton biovolume and cyanotoxin synthetase genes differed among lakes and by cyanoHAB history. Samples from lakes with documented blooms were associated with marginally higher total phosphorus. Non-metric multidimensional scaling was used to identify which environmental factors influenced community structure. Our study demonstrates the importance of multifaceted approaches to detect cyanobacteria that may only be apparent during ephemeral bloom events and the similarities among lakes with and without a history of bloom reports. This work contributes to a better understanding of cyanoHAB occurrence in Adirondack lakes, and conditions that may cause low nutrient lakes to be susceptible to cyanoHABs.

New York↗