USGS scientist measuring pH and other water properties on the banks of Fourmile Creek, Iowa, before collecting a sediment sample for laboratory biodegradation experiments on potential wastewater indicators, such as caffeine, nicotine, and cotinine.

Glass serum vials (bottles in the foreground and in the box) are used to construct microcosms for laboratory biodegradation experiments on potential wastewater indicators, such as caffeine, nicotine, and cotinine. The syringe is use for injecting chemicals for testing and withdrawing samples for analysis. Radioactive labeled chemicals (vial on right) are used so reaction products can be identified.

Aquariums where male fathead minnows were exposed to the effluent from a wastewater treatment plant. USGS scientists and their colleagues found that exposure to the wastewater from a sewage treatment plant caused endocrine disruption in the minnows.

Biosolids are the sludge generated by the treatment of sewage at wastewater treatment plants (WWTPs). WWTPs produce a variety of biosolids products for agricultural, landscape, and home use. Depicted in the diagram is an activated sludge tank at a wastewater treatment plant (upper left) and a holding area for biosolids (lower right). (The two photos are not from the same facility.)

Concentrations of rare earth elements in wastewater discharged to Boulder Creek, Colorado, compared with upstream and downstream samples. Concentrations are normalized to the North American Shale Composite, and shown on a logarithmic scale. The graph shows that the discharge from wastewater treatment plants can be enriched with gadolinium (Gd).

Average frequency of detection of emerging contaminants by compound class in 10 wastewater discharges from across the Nation. Numbers in parentheses indicate the number of compounds in each class.

Cyanobacterial accumulation at Binder Lake, IA, dominated by the blue green algae Microcystis sp. with a dead fish. USGS scientists studied the effects of harmful algal blooms on lake water quality found that blooms of blue-green algae (cyanobacteria) in Midwestern lakes produced mixtures of cyanotoxins and taste-and-odor causing compounds, which co-occurred in lake water samples.

Marion Reservoir, KS, with a posted advisory warning the public not to come into contact with the cyanobacteria bloom present in the lake (circa 2006). USGS scientists investigated the effects of harmful algal blooms like this one on lake water quality in several Midwestern lakes.

Dripping algae leaves an impact — A USGS scientist collecting a sample of algae for analysis during a study of the effects of harmful algal blooms on lake water quality. The divots left from the algae dripping from the sampler shows how thick these accumulations can be. Microcystis sp. dominated this accumulation at Binder Lake, Iowa.

USGS scientists use a variety of microbiological and chemical methods to evaluate the microbiological quality of water. In this photo, a USGS scientist prepares to analyze bacterial DNA extracted from water samples.

A conceptual diagram of the setup of the subsurface tracer test. A solution of bromide (conservative tracer), 17ß-estradiol, 4-nonylphenol, and sulfamethoxazole was injected into the subsurface. A series of corresponding water samples were collected from the multilevel sampler down gradient of the injection well.

USGS scientist determining if enough dissolved oxygen is present for biodegradation of hormones in Fourmile Creek, Iowa. A team of scientists demonstrated there is a significant potential for the biodegradation of three hormones, estrone, 17ß-estradiol, and testosterone, in the bottom sediments of streams that received wastewater from sewage treatment plants.