Geology topics

Matthew W. Johnston

Publications and source records attributed to Matthew W. Johnston.

17 recordsLinked to original sources

USGS2016

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, water year 2015

Significant Findings An analysis of total-dissolved-gas (TDG) and water-temperature data collected at eight fixed monitoring stations on the lower Columbia River in Oregon and Washington in water year 2015 indicated the following: All but 1 of the 85 TDG sensor laboratory checks that were performed after field deployment were within ±0.5-percent saturation of a primary standard. After 3–4 weeks of deployment in the river, 79 of 89 TDG sensor field checks were within ±1.0-percent saturation of a secondary standard. Nine of the field checks greater than ±1.0-percent saturation occurred at the John Day Dam tailwater station and resulted in periods of deleted TDG data at the station. All 90 barometric pressure field checks were within ±1 millimeter of mercury of a primary stand-ard, and all 90 water-temperature field checks were within ±0.2 degrees Celsius of a secondary standard. TDG data were considered complete if received in real time and within 1-percent saturation of the expected value on the basis of calibration data, replicate quality-control measurements, and comparison to river conditions at adjacent stations. For the eight monitoring stations, data completeness ranged from 71.9 to 99.8 percent. All quality-assurance values exceed the criteria established by the U.S. Army Corps of Engineers TDG monitoring plan. Criteria for data completeness (95-percent) were met at seven of the eight monitoring stations. Deleted data at the John Day tailwater station resulted in data completeness below criteria.

Oregon, Washington↗

USGS2015

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, water year 2014

Significant Findings An analysis of total-dissolved-gas (TDG) and water-temperature data collected at eight fixed monitoring stations on the lower Columbia River in Oregon and Washington in water year 2014 indicated the following: All 81 TDG sensor laboratory checks that were performed after field deployment were within plus or minus (±) 0.5-percent saturation of a primary standard. After 3-4 weeks of deployment in the river, 68 of 75 TDG sensor field checks were within ±1.0-percent saturation of a secondary standard. Six of the field checks greater than ±1.0-percent saturation occurred at the John Day tailwater station, and three of these six checks resulted in periods of deleted data at the station. All 77 barometric pressure field checks were within ±1 millimeter of mercury of a primary standard, and all 74 water-temperature field checks were within ±0.2 degrees Celsius of a secondary standard. TDG data were considered complete if they were received in real time and were within 1-percent saturation of the expected value on the basis of calibration data, replicate quality-control measurements, and comparison to river conditions at adjacent stations. For the eight monitoring stations, data completeness ranged from 78.2 to 100 percent. All quality-assurance values exceed the criteria established by the U.S. Army Corps of Engineers TDG monitoring plan. Criteria for data completeness (95 percent) were met at six of the eight monitoring stations. Deleted data at the John Day tailwater station and missed transmissions at the Camas station resulted in data completeness below criteria.

Oregon, Washington↗

USGS2014

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, water year 2013: quality-assurance data and comparison to water-quality standards

Significant Findings An analysis of total-dissolved-gas (TDG) and water-temperature data collected at eight fixed monitoring stations on the lower Columbia River in Oregon and Washington in water year 2013 indicated the following: During the spill season of April–August 2013, the averages of the 12 highest hourly TDG values in a day were periodically greater than 115-percent saturation for the forebay stations (John Day navigation lock, The Dalles forebay, and Bonneville forebay) and the Camas station. The 12 highest average daily values of TDG were also periodically greater than 120-percent saturation at Cascade Island. TDG values at the other tailwater stations (John Day Dam tailwater, The Dalles tailwater, and Warrendale) did not exceed 120-percent saturation. During parts of July, August, and September 2013, hourly water temperatures were greater than 20 degrees Celsius at all eight monitoring stations on the lower Columbia River. All of the 98 TDG sensor laboratory checks that were performed after field deployment were within ±0.5-percent saturation of a primary standard. After 3–4 weeks of deployment in the river, all but 1 of 85 TDG sensor field checks were within ±1.0-percent saturation of a secondary standard. All but 1 of 87 barometric pressure field checks were within ±1 millimeter of mercury of a primary standard, and all 86 water-temperature field checks were within ±0.2 degrees Celsius of a secondary standard. For the eight monitoring stations, a total of 99.2 percent of the TDG data were received in real time and were within 1-percent saturation of the expected value on the basis of calibration data, replicate quality-control measurements, and comparison to river conditions at adjacent sites. Data completeness for the monitoring stations ranged from 97.7 to 100 percent. All quality-assurance and data completeness values exceed the criteria established by the U.S. Army Corps of Engineers TDG monitoring plan.

Oregon, Washington↗

USGS2013

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, water year 2012: Quality-assurance data and comparison to water-quality standards

Significant Findings Air is entrained in water as it is flows through the spillways of dams, which causes an increase in the concentration of total dissolved gas in the water downstream from the dams. The elevated concentrations of total dissolved gas can adversely affect fish and other freshwater aquatic life. An analysis of total-dissolved-gas and water-temperature data collected at eight monitoring stations on the lower Columbia River in Oregon and Washington in 2012 indicated the following: During parts of the spill season of April–August 2012, hourly values of total dissolved gas (TDG) were larger than 115-percent saturation for the forebay stations (John Day navigation lock, The Dalles forebay, and Bonneville forebay) and the Camas station. Hourly values of total dissolved gas were larger than 120-percent saturation for the tailwater stations (John Day Dam tailwater, The Dalles tailwater, Cascade Island, and Warrendale). During parts of August and September 2012, hourly water temperatures were greater than 20°C (degrees Celsius) at the eight stations on the lower Columbia River. According to the State of Oregon water-temperature standard, the 7-day average of the daily maximum temperature of the lower Columbia River should not exceed 20°C; Washington regulations state that the 1-day maximum should not exceed 20°C as a result of human activities. Of the 98 laboratory TDG checks that were performed on instruments after field deployment, all were within ± 0.7-percent saturation. All but 1 of the 83 field checks of TDG sensors with a secondary standard were within ± 1.0-percent saturation after 3–4 weeks of deployment in the river. All 88 of the field checks of barometric pressure were within ±1 millimeter of mercury of a primary standard, and all 85 water-temperature field checks were within ±0.2°C of a secondary standard. For the eight monitoring stations in water year 2012, a total of 97.0 percent of the TDG data were received in real time and were within 1-percent saturation of the expected value on the ba-sis of calibration data, replicate quality-control measurements in the river, and comparison to ambient river conditions at adjacent sites. Data received from the Cascade Island site were only 77.8 percent complete because the equipment was destroyed by high water. The other stations ranged from 98.9 to 100.0 percent complete.

Oregon, Washington↗

USGS2012

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, water year 2011: Quality-assurance data and comparison to water-quality standards

Significant Findings Air is entrained in water as it is flows through the spillways of dams, which causes an increase in the concentration of total dissolved gas in the water downstream from the dams. The elevated concentrations of total dissolved gas can adversely affect fish and other freshwater aquatic life. An analysis of total-dissolved-gas and water-temperature data collected at eight monitoring stations on the lower Columbia River in Oregon and Washington in 2011 indicated the following: During the spill season of April–August 2011, hourly values of total dissolved gas (TDG) were larger than 115-percent saturation for the forebay (John Day navigation lock, The Dalles forebay, and Bonneville forebay) and Camas stations. Hourly values of total dissolved gas were larger than 120-percent saturation for the tailwater stations (John Day Dam tailwater, The Dalles tailwater, Cascade Island, and Warrendale). During parts of August and September 2011, hourly water temperatures were greater than 20°C (degrees Celsius) at the eight stations on the lower Columbia River. According to the State of Oregon water-temperature standard, the 7-day average maximum temperature of the lower Columbia River should not exceed 20°C; Washington regulations state that the 1-day maximum should not exceed 20°C as a result of human activities. Of the 79 laboratory TDG checks that were performed on instruments after field deployment, all were within ± 0.5-percent saturation and only 2 checks were out of calibration by more than 2 mm of Hg. All but 4 of the 66 field checks of TDG sensors with a secondary standard were within ± 1.0-percent saturation after 3–4 weeks of deployment in the river. All 67 of the field checks of barometric pressure were within ±1 millimeter of mercury of a primary standard, and all 66 water-temperature field checks were within ±0.2°C of a secondary standard. For the eight monitoring stations in water year 2011, a total of 93.5 percent of the TDG data were received in real time and were within 1-percent saturation of the expected value on the basis of calibration data, replicate quality-control measurements in the river, and comparison to ambient river conditions at adjacent sites. Data received from the Cascade Island site were only 34.9% complete because the equipment was destroyed by high water. The other stations ranged from 99.6 to 100 percent complete.

Oregon, Washington↗

USGS2011

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, water year 2010: Quality-assurance data and comparison to water-quality standards

Significant Findings When water is released through the spillways of dams, air is entrained in the water, increasing the downstream concentration of dissolved gases. Excess dissolved-gas concentrations can have adverse effects on freshwater aquatic life. The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, collected dissolved-gas and water-temperature data at eight monitoring stations on the lower Columbia River in Oregon and Washington in 2010. Significant findings from the data include: During the spill season of April through August 2010, hourly values of total dissolved gas (TDG) were occasionally larger than 115-percent saturation for the forebay stations (John Day navigation lock, The Dalles forebay, Bonneville forebay, and Camas). Hourly values of total dissolved gas were occasionally larger than 120-percent saturation for four tailwater stations (John Day Dam tailwater, The Dalles tailwater, Cascade Island, and Warrendale). From late July to late August or early September 2010, hourly water temperatures were greater than 20°C (degrees Celsius) at the eight stations on the lower Columbia River. According to the State of Oregon temperature standard, the 7-day average maximum temperature of the lower Columbia River should not exceed 20°C Washington regulations state that the 1-day maximum should not exceed 20°C as a result of human activities. All 105 laboratory checks of the TDG sensors (without the membrane attached) with a certified pressure gage were within ± (plus or minus) 0.5 percent saturation after 3 to 4 weeks of deployment in the river. All but 1 of the 85 in situ field checks of TDG sensors with a secondary standard were within ± 2.0-percent saturation after 3-4 weeks of deployment in the river. All 88 of the field checks of barometric pressure were within ± 1 millimeter of mercury of a primary standard, and all 87 water-temperature field checks were within ± 0.2 ° C of a secondary standard. For the eight monitoring stations in water year 2010, a total of 99.7 percent of the TDG data were received in real time and were within 1-percent saturation of the expected value on the basis of calibration data, replicate quality-control measurements in the river, and comparison to ambient river conditions at adjacent stations. Data received from the individual stations ranged from 98.4 to 100.0 percent complete.

Oregon, Washington↗

USGS2011

Water-quality in the North Santiam River Basin, Oregon— Comparison of water-quality data for water year 2007 with the preceding period of record

Water-quality data have been collected in the North Santiam River basin since 1998. During water year 2007, eight monitoring stations were operated throughout the basin. Streamflow data were collected at all but one of these sites. This report presents a comparison of the water-quality and streamflow data collected at each monitoring station from monitor installation through water year 2006 with the data for water year 2007. Data were compiled monthly and annually to identify extreme values by season and for entire periods of study.

Oregon↗

USGS2011

Modeling hydrodynamics, water temperature, and water quality in the Klamath River upstream of Keno Dam, Oregon, 2006-09

A hydrodynamic, water temperature, and water-quality model was constructed for a 20-mile reach of the Klamath River downstream of Upper Klamath Lake, from Link River to Keno Dam, for calendar years 2006-09. The two-dimensional, laterally averaged model CE-QUAL-W2 was used to simulate water velocity, ice cover, water temperature, specific conductance, dissolved and suspended solids, dissolved oxygen, total nitrogen, ammonia, nitrate, total phosphorus, orthophosphate, dissolved and particulate organic matter, and three algal groups. The Link-Keno model successfully simulated the most important spatial and temporal patterns in the measured data for this 4-year time period. The model calibration process provided critical insights into water-quality processes and the nature of those inputs and processes that drive water quality in this reach. The model was used not only to reproduce and better understand water-quality conditions that occurred in 2006-09, but also to test several load-reduction scenarios that have implications for future water-resources management in the river basin. The model construction and calibration process provided results concerning water quality and transport in the Link-Keno reach of the Klamath River, ranging from interesting circulation patterns in the Lake Ewauna area to the nature and importance of organic matter and algae. These insights and results include: * Modeled segment-average water velocities ranged from near 0.0 to 3.0 ft/s in 2006 through 2009. Travel time through the model reach was about 4 days at 2,000 ft 3 /s and 12 days at 700 ft3/s flow. Flow direction was aligned with the upstream-downstream channel axis for most of the Link-Keno reach, except for Lake Ewauna. Wind effects were pronounced at Lake Ewauna during low-flow conditions, often with circulation in the form of a gyre that rotated in a clockwise direction when winds were towards the southeast and in a counterclockwise direction when winds were towards the northwest. * Water temperatures ranged from near freezing in winter to near 30 degrees C at some locations and periods in summer; seasonal water temperature patterns were similar at the inflow and outflow. Although vertical temperature stratification was not present at most times and locations, weak stratification could persist for periods up to 1-2 weeks, especially in the downstream parts of the reach. Thermal stratification was important in controlling vertical variations in water quality. * The specific conductance, and thus density, of tributaries within the reach usually was higher than that of the river itself, so that inflows tended to sink below the river surface. This was especially notable for inflows from the Klamath Straits Drain, which tended to sink to the bottom of the Klamath River at its confluence and not mix vertically for several miles downstream. * The model was able to capture most of the seasonal changes in the algal population by modeling that population with three algal groups: blue-green algae, diatoms, and other algae. The blooms of blue-green algae, consisting mostly of Aphanizomenon flos aquae that entered from Upper Klamath Lake, were dominant, dwarfing the populations of the other two algae groups in summer. A large part of the blue-green algae population that entered this reach from upstream tended to settle out, die, and decompose, especially in the upper part of the Link-Keno reach. Diatoms reached a maximum in spring and other algae in midsummer. * Organic matter, occurring in both dissolved and particulate forms, was critical to the water quality of this reach of the Klamath River, and was strongly tied to nutrient and dissolved-oxygen dynamics. Dissolved and particulate organic matter were subdivided into labile (quickly decaying) and refractory (slowing decaying) groups for modeling purposes. The particulate matter in summer, consisting largely of dead blue-green algae, decayed quickly. Consequently, this particulate matt

Oregon↗

USGS2010

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, water year 2009: Quality-assurance data and comparison to water-quality standards

Significant Findings When water is released through the spillways of dams, air is entrained in the water, increasing the downstream concentration of dissolved gases. Excess dissolved-gas concentrations can have adverse effects on freshwater aquatic life. The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, collected dissolved-gas and water-temperature data at eight monitoring stations on the lower Columbia River in Oregon and Washington in 2009. Significant findings from the data include: During the spill season of April through August 2009, hourly values of total dissolved gas (TDG) were occasionally larger than 115-percent saturation for the forebay stations (John Day navigation lock, The Dalles forebay, Bonneville forebay, and Camas). Hourly values of total dissolved gas were occasionally larger than 120-percent saturation for two tailwater stations (John Day Dam tailwater and Cascade Island). From mid- to late July to mid-September 2009, water temperatures were greater than 20°C (degrees Celsius) at seven stations on the lower Columbia River. According to the State of Oregon temperature standard, the 7-day average maximum temperature of the lower Columbia River should not exceed 20°C; Washington regulations state that the 1-day maximum should not exceed 20°C as a result of human activities. All 96 laboratory checks of the TDG sensors with a certified pressure gage were within 0.4 percent saturation after 3 to 4 weeks of deployment in the river. All but 2 of the 73 in situ field checks of TDG sensors with a secondary standard were within ± (plus or minus) 1.0-percent saturation after 3-4 weeks of deployment in the river. All 74 of the field checks of barometric pressure were within ±2.0 millimeters of mercury of a secondary standard, and all 65 water-temperature field checks were within ±0.2°C. For the eight monitoring stations in water year 2009, a total of 99.2 percent of the TDG data were received in real time by the USGS satellite downlink and were within 1-percent saturation of the expected value on the basis of calibration data, replicate quality-control measurements in the river, and comparison to ambient river conditions at adjacent sites. Data received from the individual stations ranged from 97.0 to 100.0 percent complete.

Oregon, Washington↗

USGS2008

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, 2008: Quality-assurance data and comparison to water-quality standards

Significant Findings When water is released through the spillways of dams, air is entrained in the water, increasing the downstream concentration of dissolved gases. Excess dissolved-gas concentrations can have adverse effects on freshwater aquatic life. The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, collected dissolved-gas and water-temperature data at eight monitoring stations on the lower Columbia River in Oregon and Washington in 2008. Significant findings from the data include: During the spill season of April through August 2008, hourly values of total-dissolved-gas (TDG) concentration were occasionally larger than 115-percent saturation for the forebay stations (John Day navigation lock, The Dalles forebay, Bonneville forebay, and Camas). Hourly values of TDG concentration were occasionally larger than 120-percent saturation for tailwater stations (John Day tailwater, The Dalles tailwater, and Cascade Island). From late July to September 2008, water temperatures were greater than 20°C (degrees Celsius) at seven stations on the lower Columbia River. According to the State of Oregon temperature standard, the 7-day average maximum temperature of the lower Columbia River should not exceed 20°C; Washington regulations state that the 1-day maximum should not exceed 20°C as a result of human activities. Each of the in situ field checks of TDG sensors with a secondary standard was within ±(plus or minus) 1-percent saturation after 3 to 4 weeks of deployment in the river. All field checks of barometric pressure were within ±2.0 millimeters of mercury of a secondary standard, and water-temperature field checks were all within ±0.2°C. For the eight monitoring stations in water year 2008, an average of 99.6 percent of the TDG data were received in real time by the USGS satellite downlink and were within 1-percent saturation of the expected value on the basis of calibration data, replicate quality-control measurements in the river, and comparison to ambient river conditions at adjacent stations. Data received from the individual stations ranged from 98.8 to 100.0 percent complete.

Oregon, Washington↗

USGS2007

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, 2007: Quality-assurance data and comparison to water-quality standards

Lower Columbia River↗

USGS2006

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, 2006: Quality-assurance data and comparison to water-quality standards

Significant Findings When water is released through the spillways of dams, air is entrained in the water, increasing the downstream concentration of dissolved gases. Excess dissolved-gas concentrations can have ad-verse effects on freshwater aquatic life. The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, collected dissolved-gas concentration and water-temperature data at eight stations on the lower Columbia River in 2006. Significant findings from the data include: Variances to the Oregon and Washington water-quality standards for total dissolved gas were exceeded at all of the monitoring stations: Cascade Island (67 days), Camas (60 days), Bonneville forebay (51 days), The Dalles forebay (36 days), John Day tailwater (35 days), John Day navigation lock (20 days), The Dalles tailwater (8 days), and Warrendale (4 days). From early July to the end of August 2006, water temperatures were above 20°C (degrees Celsius) at each of the eight lower Columbia River stations. According to the Oregon temperature standard, the 7-day average maximum temperature of the lower Columbia River should not exceed 20°C; Washington regulations state that the 1-day maximum should not exceed 20°C due to human activities. Most field checks of total-dissolved-gas sensors with a secondary standard were within ± (plus or minus) 1% saturation. All of the field checks of barometric pressure were within ±1 millimeter of mercury of a secondary standard, and water temperature field checks were all within ±0.2°C. For the eight monitoring stations in water year 2006, an average of 99.1% of the total-dissolved-gas data were received in real time by the USGS satellite downlink and were within 1% saturation of the expected value on the basis of calibration data, replicate quality-control measurements in the river, and comparison to ambient river conditions at adjacent stations.

Oregon, Washington↗

USGS2006

Field comparison of optical and Clark cell dissolved oxygen sensors in the Tualatin River, Oregon, 2005

Explore the source record for details and available documents.

Open-File Report↗

USGS2005

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, 2005: quality-assurance data and comparison to water-quality standards

Significant Findings When water is released through the spillways of dams, air is entrained in the water, increasing the downstream concentration of dissolved gases. Excess dissolved-gas concentrations can have adverse effects on freshwater aquatic life. The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, collected dissolved-gas and water-temperature data at eight sites on the lower Columbia River in 2005. Significant findings from the data include: Variances to the Oregon and Washington water-quality standards for total dissolved gas were exceeded at five of the monitoring sites: Camas (11 days), John Day tailwater (3 days), The Dalles forebay (3 days), Bonneville forebay (3 days), and John Day navigation lock (1 day). From mid-July to early September, water temperatures were above 20°C (degrees Celsius) at each of the eight lower Columbia River sites. According to the Oregon temperature standard, the 7-day average maximum temperature of the lower Columbia River should not exceed 20°C; Washington regulations state that the 1-day maximum should not exceed 20°C due to human activities. Most field checks of total-dissolved-gas sensors with a secondary standard were within ± (plus or minus) 1% saturation. Most of the field checks of barometric pressure were within ±1 millimeter of mercury of a secondary standard, and water temperature field checks were all within ±0.2°C. For the eight monitoring sites in water year 2005, an average of 98.2% of the total-dissolved-gas data were received in real time by the USGS satellite downlink and were within 1% saturation of the expected value, based on calibration data, replicate quality-control measurements in the river, and comparison to ambient river conditions at adjacent sites.

Oregon, Washington↗

USGS2003

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, 2003: Quality-assurance data and comparison to water-quality standards

Significant Findings When water is released through the spillways of dams, air is entrained in the water, increasing the concentration of total dissolved gas. Excess dissolved-gas concentrations can have adverse effects on freshwater aquatic life. The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, collected total- dissolved-gas and water-temperature data at seven sites on the lower Columbia River in 2003. Significant findings from the data include: For the seven monitoring sites in water year 2003, an average of 98.9% of the total-dissolved-gas data were received in real time by the USGS satellite downlink and were within 1% saturation of the expected value, based on calibration data, replicate quality-control measurements in the river, and comparison to ambient river conditions at adjacent sites. Most field checks of total-dissolved-gas sensors with a secondary standard were within plus or minus 1% saturation. Field checks of barometric pressure and water temperature were usually within plus or minus 1 millimeter of mercury and plus or minus 0.1 degree Celsius, respectively. The variances to the States of Oregon and Washington water-quality standards for total dissolved gas were exceeded at six of the seven monitoring sites. The sites at Camas and Bonneville forebay had the most days exceeding the variance of 115% saturation. The forebay exceedances may have been the result of the cumulative effects of supersaturated water moving downstream through the lower Columbia River. Apparently, the levels of total dissolved gas did not decrease rapidly enough downstream from the dams before reaching the next site. From mid-July to mid-September, water temperatures were usually above 20 degrees Celsius at each of the seven lower Columbia River sites. According to the Oregon water-quality standard, when the temperature of the lower Columbia River exceeds 20 degrees Celsius, no measurable temperature increase resulting from anthropogenic activities is allowed. Transient increases of about 1 degree Celsius were noted at the John Day forebay site, due to localized solar heating.

Oregon, Washington↗

USGS2002

Total dissolved gas and water temperature in the lower Columbia River, Oregon and Washington, 2002: Quality-assurance data and comparison to water-quality standards

Significant Findings The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, collected total-dissolved-gas and water-temperature data at eight sites near dams on the lower Columbia River in 2002. When water is released through the spillways of dams, air is entrained in the water, increasing the concentration of total dissolved gas to levels that can have adverse effects on freshwater aquatic life. Significant findings include: For the eight monitoring sites in water year 2002, an average of 99.6% of the total-dissolved gas data were received in real time by the USGS satellite downlink and were within 1% saturation of the expected value, based on calibration data and ambient river conditions at adjacent sites. Most field checks of total-dissolved-gas sensors with a secondary standard were within 1% saturation. Field checks of barometric pressure and water temperature were usually within 1 millimeter of mercury and 0.05 degrees Celsius, respectively. In June and July 2002, spills exceeded 140,000 cubic feet per second at the John Day, The Dalles, and Bonneville Dams. These spills resulted in levels of total dissolved gas that exceeded 120% saturation downstream of the dams. The variance to the State of Oregon water-quality standard for total dissolved gas of 110% saturation was exceeded at seven of the eight monitoring sites. The sites at Camas and Bonneville are considered forebay sites and had the most days exceeding the variance of 115% saturation. The forebay exceedances may have been the result of the cumulative effects of significant spill throughout the lower Columbia River. Apparently, the levels of total dissolved gas did not dissipate rapidly enough downstream of the dams before reaching the next site. From mid-July to mid-September, water temperatures were usually above 20 degrees Celsius at each of the seven lower Columbia River sites in operation. According to the Oregon water-quality standard, when the temperature of the lower Columbia River exceeds 20 degrees Celsius, no measurable temperature increase resulting from anthropogenic activities is allowed.

Oregon, Washington↗

USGS2001

Data-collection methods, quality-assurance data, and site considerations for total dissolved gas monitoring, lower Columbia River, Oregon and Washington, 2000

Excessive total dissolved gas pressure can cause gas-bubble trauma in fish downstream from dams on the Columbia River. In cooperation with the U.S. Army Corps of Engineers, the U.S. Geological Survey collected data on total dissolved gas pressure, barometric pressure, water temperature, and probe depth at eight stations on the lower Columbia River from the John Day forebay (river mile 215.6) to Camas (river mile 121.7) in water year 2000 (October 1, 1999, to September 30, 2000). These data are in the databases of the U.S. Geological Survey and the U.S. Army Corps of Engineers. Methods of data collection, review, and processing, and quality-assurance data are presented in this report.

Oregon, Washington↗