Data

Additional Resources

Articles, Readings, and Websites

Media

  • CREWS Tracer Test Video

Video transcript: "Hi. This is Rob Payn. I'm a hydrologist at Montana State University. We are about to do a tracer test in this stream. This is Louse Creek in the Judith River Watershed, and we are really interested in how streams process things like nitrate, so we watch the stream chemistry upstream and downstream and see how nitrate is changing over the reach. For our calculations it’s really important we know how long it takes a parcel of water to go from our upstream station to our downstream station. So I’m about to…Let’s get these buckets in the frame here. I’m about to take a couple buckets of salt water. I’ve put about one and a half kilograms of feed salt in each of these buckets and some stream water. Mixed it up and dissolved it. And I’m about to dump that water into the stream and we will measure the electrical conductivity of the water which will go up when the water gets saltier. And that way we will know how long it takes this salt to get to the downstream end of the reach."

  • CREWS SUNA Video

Video transcript: "Hi, my name is Rob Payn. I’m a hydrologist at Montana State University. This is a SUNA – or a Submersible Ultraviolet Nitrate Analyzer. We put these in streams like this one in the Judith River Watershed. We put them in for many days to many weeks or even many months. And we use them to track how the nitrate changes over the day. Because of different processes like photosynthesis in the stream from algae or evapotransporation limiting how much water gets into the stream during different times of day. That creates a variation in nitrate over the day, and we are hoping we can extract information about measuring that nitrate to understand how those processes work."