Water Quality at the University of Rochester

Katherine M. L. Garner

University of Rochester
OPT 307/407


The goal of this project was to investigate the content of the water from and around the University of Rochester. I took eight samples from various locations in hopes of investigating the differences within these samples. Once the samples were collected, drops of the water were placed on a silica wafer on a sample stub and allowed to dry. These samples were then sputtercoated with approximatley 6 nm of gold in order to render them conductive. They were then viewed using the Institute of Optics at the University of Rochesterís Zeiss-Leo DSM982 scanning electron microscope (SEM). Images were taken using the backscattered electrons detector (BSD), the In-Lens detector, and the secondary electron detector. Compositional analysis was completed using the x-ray spectrometer and x-ray mapping was utilized to image the samples based on composition. After the images were collect some were colorized to highlight regions of importance or compositional differences.


Bottled Water
Melted Ice Cubes
Toilet Bowl Water
Bathroom Tap Water
Soda Fountain Water
Water Bottle Refill Station
Genesee River Water

Bottled Water

This brand of bottled water is advertised as water from public water sources that has been purified through a proprietary seven-step purification process." The bottler attempts to remove all salts, chlorides, and other taste-altering substances in order to bottle completely pure water. The "Water Quality and Information" tab of their homepage provides a sample water quality analysis from 2010.

Aquafina GrainsAquafina Grains X-ray

Figure 1: SE2 image of grains found in the bottled water sample along with X-ray spectrometry analysis indicating a composition of iron, chromium, and nickel. These are most likely contaminants from sample preparation.

Aquafina SaltAquafina Salt X-ray

Figure 2: SE2 close-up of another grain found in the bottled watersample. X-ray analysis suggests it is a NaCl dirt and salt compound with some potassium, carbon, oxygen, and silica. Once again, it is likely a contaminant from sample preparation.

Melted Ice Cubes

As the weather turns warmer, more and more Rochester students can be found purchasing iced drinks from the on campus vendors. A sample of the ice they use in these drinks was taken and allowed to partially melt. This melt water was used for this sample.

Melted Ice GrainsMelted Ice Grains X-ray

Figure 3: SE2 image of a grain found in the melted ice cube water sample. The x-ray analysis suggests this grain is a composition of organic material (there is carbon and oxygen present) and salt compounds (sodium, chlorine, potassium, and calcium). There is also a small amount of sulfur present. This is likely some sort of piece of dirt that came in contact with salt compounds either in the ice or while drying.

Melted Ice DisruptionMelted Ice Disruption X-ray

Figure 4: SE2 image of a dendritic salt formation overlaying cracks in the silica substrate. X-ray analysis suggests that the formation is a sodium chloride drying pattern.

Toilet Bowl Water

This sample was taken from one of the toilet bowls in the women's bathroom outside of the IT Center. The sample showed three recurring specimens. Radial salt drying patterns, silica shards, and grains of dirt and salt compounds.

Toilet Bowl Water Salt PatternToilet Bowl Water Salt Pattern X-ray

Figure 5: SE2 image of dried salt. X-ray analysis indicates it is a sodium chloride formation.

Toilet Bowl Water Map
Toilet Bowl Water Na MapToilet Bowl Water Cl MapToilet Bowl Water Si Map

Figure 6: X-ray analysis of a dried salt formation. The top is an image of the formation, the bottom left is a map of x-rays emitted from sodium atoms, the bottom middle indicates the location of chlorine atoms, and the bottom right indicates the location of silica atoms.

Bathroom Tap Water

This tap water was collected from the second floor women's bathroom in Hutchinson Hall.

Bathroom Tap Water Hair and SaltBathroom Tap Water Hair and Salt Colorized

Figure 7: BSD and Photoshop colorization of salt dried on a thread found in the Bathroom Tap Water sample. The thread is most likely a contaminant from the sample preparation, and the salts either precipitated out from the water or were detergents from the thread.

Bathroom Tap Water Hair and Salt C MapBathroom Tap Water Hair and Salt O MapBathroom Tap Water Hair and Salt Cl MapBathroom Tap Water Hair and Salt Na MapBathroom Tap Water Hair and Salt K MapBathroom Tap Water Hair and Salt Mg MapBathroom Tap Water Hair and Salt Si Map

Figure 8: X-ray analysis of the thread and salt. Top left: carbon; top middle: oxygen; top right: chlorine; middle left: sodium; middle middle: potassium; middle right: magnesium; bottom middle: silica.

Soda Fountain Water

Soda fountains often have a small tab over one of the beverage options labeled 'water.' This sample came from The Commons' soda fountain water tab.

Soda Fountain Crystal

Figure 9: This is an SE2 image of crystalline grains found in the water taken from the soda fountain.

Soda Fountain X-ray 1Soda Fountain X-ray 2

Figure 10: These are X-ray spectrometry analyses of other amorphous grains found in the sample. The analyses indicate that the grains are mostly dirt with salts incorpated. The grains are mostly composed of carbon and oxygen, but also have fluorine, sodium, and magnesium within them.

Water Bottle Refill Station

The University of Rochester recently installed several Elkay EZH2O bottle filling stations as part of its Go Green initiative. These stations, as seen at Elkay - Hydration Water Filling Station, have been placed on campus to provide students with a convenient and easy way to fill their reusable water bottles with filtered water. The sample used in this report was taken from the water bottle refill station outside of the IT Center when its filter status was 'green.'

Water Bottle Refill Station GrainWater Bottle Refil Station Grain

Figure 11: SE2 image and X-ray analysis of a grain found within the Water Bottle Refill Station water sample. The X-ray analysis suggests this is some organic material (carbon and oxygen is present) mixed with a couple different salts (sodium, magnesium, sulfur, chlorine, potassium, and calcium are all present in varying concentrations).

Water Bottle Refill Station DiatomWater Bottle Refill Station Drying Pattern

Figure 12: The figure on the left is a SE2 image of an unknown object found in the water from the Water Bottle Refill Station. It is possible that it is a freshwater diatom. The image on the right is an In-Lens image of the patterns left on the silica wafer after the sample dried.

Water Bottle Refill Station Aluminum ShardWater Bottle Refill Station Aluminum Shard X-ray

Figure 13: This is a SE2 image and X-ray analysis of what appears to be a shard of aluminium.

Genesee River Water

The Genesee River winds around the University of Rochester's campus and makes up approximately half of the campus' perimeter. The crew team practices in the river and countless people run, bike, and walk along side it throughout the seasons. While the sludge and silt at the bottom prevent the Genesee from being the deepest of rivers once it has approached campus, the Genesee runs deep within Rochester's popular culture. The focus of our most popular school song, and mentioned often in our Alma Mater, the Genesee is a defining characteristic of our campus. With the weather warming and with Dandelion Day behind them, many students are beginning to contemplate the safety of the swim from the River Campus to the 19th Ward and back, wondering the age old question of "what, exactly, is in the Genesee?"

Genesee River Water Diatom 1Genesee River Water Diatom 1 ZoomGenesee River Water Diatom 1 Colorized

Figure 14: SE2 image of a broken diatom found in the Genesee River water sample. The middle image is a close-up of the left section of the diatom and the right image is a colorized version.

Genesee River Water Salt 1Genesee River Water Salt 1 X-ray

Figure 15: In-Lens image of a salt found in the Genesee River water sample. X-ray analysis indicates it is comprised of carbon, a relatively large amount of oxygen, some sulfur, and calcium.

Genesee River Water Diatom 2Genesee River Water Circle DiatomGenesee River Water Diatom 3

Figure 16: The left and middle images are SE2 images of diatoms found in the sample, and the right is an In-Lens image of a section of a diatom with some salt or dirt attached to its end.

Genesee River Water SphereGenesee River Water Ball

Figure 17: The image on the left is an In-Lens image of what appears to be a spherical diatom. The image on the right is an SE2 image of an unknown spherical formation.

Genesee River Water Calcium Drops Low Accelerating VoltageGenesee River Water Calcium Drops X-rayGenesee River Water Calcium Drops

Figure 18: The image on the left is an In-Lens image of what appears to be calcium grains imaged at 10.00 keV. The center image is the X-ray spectra indicating that the features contain calcium. The image on the right was imaged at 20 keV. An unknown substance has formed splotch-like patterns visible only at higher accelerating voltages.

Genesee River Water ElipseGenesee River Water Elipse X-ray

Figure 19: SE2 image of an unknown found within the Genesee River sample. X-ray analysis indicates that the unknown contains carbon and oxygen, potentially indicating that the object is organic. Also present is sulfur and calcium.

Common Contaminants

While imaging these samples a few contaminants were noticed in many, if not all, of the samples. A few of these contaminants were imaged and are shown below.

Silica Soda Fountain

Figure 20: This is a shard of silica, possibly from the silica wafer the sample was dried on. However, it could also be a diatom, with the silica wafer behind it increasing the silica signal by so much that the telltale sign of oxygen was lost. It was found in the soda fountain water sample, but many more were seen in all of the samples.

Aquafina Slime

Figure 21: SE2 image of some sort of slime-like material that contaminated many of the sample stubs. This was found in the bottled water sample.