WALLINGFORD — While driving north on Route 15, you may have noticed what looks like a shack on the side of the highway between exits 63 and 64.
The simple concrete structure is one of 70 stream gauges the United States Geological Survey has in place across Connecticut. Every month, the USGS sends a team of two people to the location to collect samples from the nearby Quinnipiac River.
“Our job is to collect the data,” said Jonathan Morrison, USGS chief of New England Water-Quality Networks and Water Availability Studies. “We analyze the data and produce scientific reports and they take the science we use and use that to help provide information for management decisions. Our job is purely science.”
On site, the team can monitor data on the height of the river, as well as water quality, temperature, dissolved oxygen and turbidity.
“Dissolved oxygen is important for fish and the temperature ranges that the river goes through is important for understanding the habitat for fish,” Morrison said. “Turbidity is measuring how cloudy the river is. It’s a surrogate for how much sediment is going down the river.”
Morrison said his team is working on a project to determine how much phosphorus the sediment contains.
“We can see what the concentration of phosphorus is in the river at the time,” Morrison said. “Phosphorus is the primary nutrient of concern in fresh water systems. It limits the amount of growth that happens.”
The state is looking to reduce the amount of phosphorus in the river. The mineral isn’t toxic, but can cause algae blooms that lower oxygen levels and endanger wildlife. Federal and state guidelines are requiring several municipalities along the river to invest millions in wastewater treatment plant upgrades to reduce phosphorus.
Brittney Jones, a hydrologic technician, said water quality can be continuously measured from the stream gauge, which sends information to a computer database.
During the last week of April, the team stopped at the Wallingford stream gauge and set up a tag line across the river for more testing.
“We’re going to go out and take a width and depth indicator sample,” Morrison said. “It allows us to relate the sample that we are taking to the flow that is going by.”
While Jones wrapped one end of the string used to measure the width of the river around a tree, Guy Holzer, another hydrologic technician, took the spool and made his way across the river, attaching it to the other side.
Once the string was secure, Holzer began taking samples for organic carbon and E. coli bacteria.
“I just love working outside, except for days like today,” Holzer said as rain started to fall. “I really enjoy the job. I believe in the job.”
While Holzer was in the middle of the river, Jones took a dissolved oxygen measurement.
“It is going to measure the water temperature, dissolved oxygen and will see how close to 100 percent saturation it is,” Morrison said. “It’s usually fairly oxygenated in this area.”
Holzer than began collecting 10 water samples. The process took about half an hour as Holzer went back and forth from the river to the shore handing off the samples to his colleagues.
Once the sampling is finished, Jones begins registering the data into her tablet computer. She then heads into the river herself to get additional readings. The group then returns to their truck, which also doubles as a mobile lab, and they get to work labeling and testing the samples they have collected.
“A big part of the job that is important is the quality of the data that we collect,” Holzer said.
After finishing at the Wallingford stream gauge, they head to North Haven where they’ll conduct another round of the same tests.
Read more articles like this and help support local journalism by subscribing to the Record Journal.
Unlimited Digital Access just 99¢
Read more articles like this by subscribing to the Record Journal.
Unlimited Digital Access for just 99¢