I never thought I’d spend so much time in a river as part of a marine science research project, but here I am and I’m having a blast!

The Newport EPA has been going on research cruises to monitor water quality in the streams and the bay of Tillamook 1-2 times per month for a year now. Two weeks ago, I got to participate in the last cruise of the study. We divided into two teams, the “bay team” and the “tributary team.” Each team took measurements of dissolved oxygen, temperature, depth, salinity, and chlorophyll on-site using a multi-parameter data sonde. We also took water samples to analyze in the lab for carbonate chemistry, nutrients, dissolved organic carbon, and dissolved inorganic carbon; each measurement requires a different type of container for the sample. To make all of this easier, the EPA has converted a trailer into a mini-lab for field sampling. We have cabinets, countertops and lots of equipment all organized and easy to access!

By monitoring many different water quality parameters at locations throughout the rivers and the bay, we’re hoping to get a holistic view of the water chemistry in this system and to identify the drivers of any changes observed in the health of the system.

The trailer rigged for water sampling on the go.

Filling a cooler with a variety of water samples. Not pictured are the DOC samples, which are placed on dry ice so that they freeze immediately.

Another part of the picture is looking at how in-stream processing changes the water chemistry, specifically the amounts of carbon and oxygen. If we can get an idea of this, then we can know which changes in water quality are due to in-stream processing versus inputs such as agricultural runoff as the river runs from the forests to the bay.

Most in-stream processing is driven by periphyton, the algae growing on the rocks at the bottom of the river. To measure these changes, we removed all the rocks from a small (about 1 square foot) area in the river and placed them in a sealed container. We measured the initial dissolved oxygen in the water, let it sit in the river for four hours, and then measured the oxygen again.

Setting up the containers to measure in-stream processing. There were 4 containers with rocks and 2 controls with only streamwater at each of the two locations.

Jody Stecher, left, and me, right, measuring the oxygen in the container after removing it from the river.

We also wanted to see how one parcel of water changes as it moves downstream. At our upstream location, we released a bag of oranges into the water. Since they float in the water, they move at about the same rate as the water, so we were hoping to take measurements when they reached the downstream location. However, after about 4 hours of waiting, we decided to let this part of the experiment go. Lesson learned: there are a lot of orange leaves in the river that look like oranges when that’s what you’re hoping to see!

Waiting for the oranges to come.

After taking so many measurements and samples in a relatively short period of time, we have quite a bit of lab work and analysis coming up! Some samples will be sent to other facilities for analysis, and some will be analyzed here. I’m excited to start making sense of these data and bring together the many parts of this project to understand the system as a whole.