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As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, an ecologist uses a net to collect a sample of aquatic invertebrates for ennumeration and identification.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, an ecologist uses a net to collect a sample of aquatic invertebrates for ennumeration and identification.
Biofilms take up pesticides in streams. Here, a hydrologic technician collects a sample of biofilm that has colonized an unglazed ceramic tile over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
Biofilms take up pesticides in streams. Here, a hydrologic technician collects a sample of biofilm that has colonized an unglazed ceramic tile over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
Biofilms take up pesticides in streams. Here, a hydrologic technician collects a sample of biofilm that has colonized an unglazed ceramic tile over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
Biofilms take up pesticides in streams. Here, a hydrologic technician collects a sample of biofilm that has colonized an unglazed ceramic tile over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
Biofilms take up pesticides in streams. Here, a hydrologic technician hold ups an unglazed ceramic tile that has been colonized by biofilm over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
Biofilms take up pesticides in streams. Here, a hydrologic technician hold ups an unglazed ceramic tile that has been colonized by biofilm over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, two hydrologic technicians record characteristics of stream habitat.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, two hydrologic technicians record characteristics of stream habitat.
Sausal Creek in central Oakland, California, is an urban creek that has been extensively modified for flood control. The USGS Regional Stream Quality Assessment assessed the water quality and ecological integrity of small streams like Sausal Creek in five major regions of the country.
Sausal Creek in central Oakland, California, is an urban creek that has been extensively modified for flood control. The USGS Regional Stream Quality Assessment assessed the water quality and ecological integrity of small streams like Sausal Creek in five major regions of the country.
Sausal Creek in central Oakland, California, is an urban creek that has been extensively modified for flood control. The USGS Regional Stream Quality Assessment assessed the water quality and ecological integrity of small streams like Sausal Creek in five major regions of the country.
Sausal Creek in central Oakland, California, is an urban creek that has been extensively modified for flood control. The USGS Regional Stream Quality Assessment assessed the water quality and ecological integrity of small streams like Sausal Creek in five major regions of the country.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a hydrologist carefully folds a filter used to collect a sample for analysis of eDNA.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a hydrologist carefully folds a filter used to collect a sample for analysis of eDNA.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a hydrologic technician records characteristics of the habitat of a highly urbanized stream.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a hydrologic technician records characteristics of the habitat of a highly urbanized stream.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a geolomorphologist assesses stream banks.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a geolomorphologist assesses stream banks.
Concentrations of polycyclic aromatic hydrocarbons (PAHs) in settings near pavement sealed with coal-tar-based sealants were substantially higher than concentrations in settings where coal-tar sealant was not used.
Concentrations of polycyclic aromatic hydrocarbons (PAHs) in settings near pavement sealed with coal-tar-based sealants were substantially higher than concentrations in settings where coal-tar sealant was not used.
Coal-tar-based sealcoat is a potent source of PAHs and related chemicals. Worn particles of coal-tar-based sealcoat are transported by rain, wind, tires, and even our feet from pavement to other environmental settings. Sealcoat product (A), after it dries, gradually abrades to a powder and becomes part of the dust on the pavement (B).
Coal-tar-based sealcoat is a potent source of PAHs and related chemicals. Worn particles of coal-tar-based sealcoat are transported by rain, wind, tires, and even our feet from pavement to other environmental settings. Sealcoat product (A), after it dries, gradually abrades to a powder and becomes part of the dust on the pavement (B).
Hydrologic Technician Denis Scanlon removes a Pankow sampler from Lincoln Creek, in Milwaukee, Wisconsin, as USGS Hydrologist Dave Saad assists. High waters make the job particularly challenging.
Hydrologic Technician Denis Scanlon removes a Pankow sampler from Lincoln Creek, in Milwaukee, Wisconsin, as USGS Hydrologist Dave Saad assists. High waters make the job particularly challenging.
Micro-samplers are sophisticated instruments that collect small "sips" of water at frequent intervals. The samples, collected every few hours, provide a picture of how rapidly water quality can change over time. These samples were analyzed for a suite of hundreds of pesticides. In 2013, the USGS Regional Stream Quality Assessment (
Micro-samplers are sophisticated instruments that collect small "sips" of water at frequent intervals. The samples, collected every few hours, provide a picture of how rapidly water quality can change over time. These samples were analyzed for a suite of hundreds of pesticides. In 2013, the USGS Regional Stream Quality Assessment (
Micro-samplers are sophisticated instruments that collect small "sips" of water at designated intervals. Installing one during high water conditions is a tricky business. The samples, collected every few hours, provide a picture of how rapidly water quality can change over time. These samples were analyzed for a suite of hundreds of pesticides.&nbs
Micro-samplers are sophisticated instruments that collect small "sips" of water at designated intervals. Installing one during high water conditions is a tricky business. The samples, collected every few hours, provide a picture of how rapidly water quality can change over time. These samples were analyzed for a suite of hundreds of pesticides.&nbs
A driveway in an upscale residential community in the Lake in the Hills, Ill, is coated with coal-tar-based sealcoat. The driveway has a basketball hoop and a skateboard ramp.
A driveway in an upscale residential community in the Lake in the Hills, Ill, is coated with coal-tar-based sealcoat. The driveway has a basketball hoop and a skateboard ramp.
Many homeowners have their driveway sealcoat to protect and beautify the underlying asphalt. Coal-tar-based sealcoat, predominantly used east of the Continental Divide, is a potent source of polycyclic aromatic hydrocarbons (PAHs). Read more about coal-tar-based sealcoat and PAHs here.
Many homeowners have their driveway sealcoat to protect and beautify the underlying asphalt. Coal-tar-based sealcoat, predominantly used east of the Continental Divide, is a potent source of polycyclic aromatic hydrocarbons (PAHs). Read more about coal-tar-based sealcoat and PAHs here.
Sealcoat particles abraded from a parking lot with coal-tar-based sealcoat collect by the curbside. Also shown is a storm drain, half coated with sealcoat, down which the loose particles will be washed by runoff.
Sealcoat particles abraded from a parking lot with coal-tar-based sealcoat collect by the curbside. Also shown is a storm drain, half coated with sealcoat, down which the loose particles will be washed by runoff.
Driveways in an upscale residential subdivision in Lake in the Hills, Ill., are coated with black coal-tar-based sealcoat, contrasting with the white cement sidewalk.
Driveways in an upscale residential subdivision in Lake in the Hills, Ill., are coated with black coal-tar-based sealcoat, contrasting with the white cement sidewalk.
Sealcoat, marketed to protect and beautify the underlying asphalt, sharply contrasts here with the light gray of unsealcoated asphalt pavement. Read more about coal-tar-based sealcoat and PAHs here.
Sealcoat, marketed to protect and beautify the underlying asphalt, sharply contrasts here with the light gray of unsealcoated asphalt pavement. Read more about coal-tar-based sealcoat and PAHs here.
The abrasive action of car tires and snow plows causes sealcoat to wear off. Here, light-colored patches indicate where the sealcoat has worn off and the underlying asphalt shows through.
The abrasive action of car tires and snow plows causes sealcoat to wear off. Here, light-colored patches indicate where the sealcoat has worn off and the underlying asphalt shows through.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, an ecologist uses a net to collect a sample of aquatic invertebrates for ennumeration and identification.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, an ecologist uses a net to collect a sample of aquatic invertebrates for ennumeration and identification.
Biofilms take up pesticides in streams. Here, a hydrologic technician collects a sample of biofilm that has colonized an unglazed ceramic tile over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
Biofilms take up pesticides in streams. Here, a hydrologic technician collects a sample of biofilm that has colonized an unglazed ceramic tile over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
Biofilms take up pesticides in streams. Here, a hydrologic technician collects a sample of biofilm that has colonized an unglazed ceramic tile over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
Biofilms take up pesticides in streams. Here, a hydrologic technician collects a sample of biofilm that has colonized an unglazed ceramic tile over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
Biofilms take up pesticides in streams. Here, a hydrologic technician hold ups an unglazed ceramic tile that has been colonized by biofilm over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
Biofilms take up pesticides in streams. Here, a hydrologic technician hold ups an unglazed ceramic tile that has been colonized by biofilm over 60-90 days. Learn more about biofilms as integrative samplers of pesticides here.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, two hydrologic technicians record characteristics of stream habitat.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, two hydrologic technicians record characteristics of stream habitat.
Sausal Creek in central Oakland, California, is an urban creek that has been extensively modified for flood control. The USGS Regional Stream Quality Assessment assessed the water quality and ecological integrity of small streams like Sausal Creek in five major regions of the country.
Sausal Creek in central Oakland, California, is an urban creek that has been extensively modified for flood control. The USGS Regional Stream Quality Assessment assessed the water quality and ecological integrity of small streams like Sausal Creek in five major regions of the country.
Sausal Creek in central Oakland, California, is an urban creek that has been extensively modified for flood control. The USGS Regional Stream Quality Assessment assessed the water quality and ecological integrity of small streams like Sausal Creek in five major regions of the country.
Sausal Creek in central Oakland, California, is an urban creek that has been extensively modified for flood control. The USGS Regional Stream Quality Assessment assessed the water quality and ecological integrity of small streams like Sausal Creek in five major regions of the country.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a hydrologist carefully folds a filter used to collect a sample for analysis of eDNA.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a hydrologist carefully folds a filter used to collect a sample for analysis of eDNA.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a hydrologic technician records characteristics of the habitat of a highly urbanized stream.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a hydrologic technician records characteristics of the habitat of a highly urbanized stream.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a geolomorphologist assesses stream banks.
As part of the Regional Stream Quality Assessments (RSQA), hydrologists, ecologists, and technicians did ecological surveys of aquatic biota and stream habitat. Here, a geolomorphologist assesses stream banks.
Concentrations of polycyclic aromatic hydrocarbons (PAHs) in settings near pavement sealed with coal-tar-based sealants were substantially higher than concentrations in settings where coal-tar sealant was not used.
Concentrations of polycyclic aromatic hydrocarbons (PAHs) in settings near pavement sealed with coal-tar-based sealants were substantially higher than concentrations in settings where coal-tar sealant was not used.
Coal-tar-based sealcoat is a potent source of PAHs and related chemicals. Worn particles of coal-tar-based sealcoat are transported by rain, wind, tires, and even our feet from pavement to other environmental settings. Sealcoat product (A), after it dries, gradually abrades to a powder and becomes part of the dust on the pavement (B).
Coal-tar-based sealcoat is a potent source of PAHs and related chemicals. Worn particles of coal-tar-based sealcoat are transported by rain, wind, tires, and even our feet from pavement to other environmental settings. Sealcoat product (A), after it dries, gradually abrades to a powder and becomes part of the dust on the pavement (B).
Hydrologic Technician Denis Scanlon removes a Pankow sampler from Lincoln Creek, in Milwaukee, Wisconsin, as USGS Hydrologist Dave Saad assists. High waters make the job particularly challenging.
Hydrologic Technician Denis Scanlon removes a Pankow sampler from Lincoln Creek, in Milwaukee, Wisconsin, as USGS Hydrologist Dave Saad assists. High waters make the job particularly challenging.
Micro-samplers are sophisticated instruments that collect small "sips" of water at frequent intervals. The samples, collected every few hours, provide a picture of how rapidly water quality can change over time. These samples were analyzed for a suite of hundreds of pesticides. In 2013, the USGS Regional Stream Quality Assessment (
Micro-samplers are sophisticated instruments that collect small "sips" of water at frequent intervals. The samples, collected every few hours, provide a picture of how rapidly water quality can change over time. These samples were analyzed for a suite of hundreds of pesticides. In 2013, the USGS Regional Stream Quality Assessment (
Micro-samplers are sophisticated instruments that collect small "sips" of water at designated intervals. Installing one during high water conditions is a tricky business. The samples, collected every few hours, provide a picture of how rapidly water quality can change over time. These samples were analyzed for a suite of hundreds of pesticides.&nbs
Micro-samplers are sophisticated instruments that collect small "sips" of water at designated intervals. Installing one during high water conditions is a tricky business. The samples, collected every few hours, provide a picture of how rapidly water quality can change over time. These samples were analyzed for a suite of hundreds of pesticides.&nbs
A driveway in an upscale residential community in the Lake in the Hills, Ill, is coated with coal-tar-based sealcoat. The driveway has a basketball hoop and a skateboard ramp.
A driveway in an upscale residential community in the Lake in the Hills, Ill, is coated with coal-tar-based sealcoat. The driveway has a basketball hoop and a skateboard ramp.
Many homeowners have their driveway sealcoat to protect and beautify the underlying asphalt. Coal-tar-based sealcoat, predominantly used east of the Continental Divide, is a potent source of polycyclic aromatic hydrocarbons (PAHs). Read more about coal-tar-based sealcoat and PAHs here.
Many homeowners have their driveway sealcoat to protect and beautify the underlying asphalt. Coal-tar-based sealcoat, predominantly used east of the Continental Divide, is a potent source of polycyclic aromatic hydrocarbons (PAHs). Read more about coal-tar-based sealcoat and PAHs here.
Sealcoat particles abraded from a parking lot with coal-tar-based sealcoat collect by the curbside. Also shown is a storm drain, half coated with sealcoat, down which the loose particles will be washed by runoff.
Sealcoat particles abraded from a parking lot with coal-tar-based sealcoat collect by the curbside. Also shown is a storm drain, half coated with sealcoat, down which the loose particles will be washed by runoff.
Driveways in an upscale residential subdivision in Lake in the Hills, Ill., are coated with black coal-tar-based sealcoat, contrasting with the white cement sidewalk.
Driveways in an upscale residential subdivision in Lake in the Hills, Ill., are coated with black coal-tar-based sealcoat, contrasting with the white cement sidewalk.
Sealcoat, marketed to protect and beautify the underlying asphalt, sharply contrasts here with the light gray of unsealcoated asphalt pavement. Read more about coal-tar-based sealcoat and PAHs here.
Sealcoat, marketed to protect and beautify the underlying asphalt, sharply contrasts here with the light gray of unsealcoated asphalt pavement. Read more about coal-tar-based sealcoat and PAHs here.
The abrasive action of car tires and snow plows causes sealcoat to wear off. Here, light-colored patches indicate where the sealcoat has worn off and the underlying asphalt shows through.
The abrasive action of car tires and snow plows causes sealcoat to wear off. Here, light-colored patches indicate where the sealcoat has worn off and the underlying asphalt shows through.