River gauges provide insight to streamflows as boaters look toward spring

BILLINGS – If you are new to rafting, canoeing, kayaking or stand-up paddle boarding, there’s a website that can provide you with some important information.

The U.S. Geological Survey has water gauges placed in rivers across the state of Montana. By logging on to the Montana streamflow website, you can see whether the Clark Fork, Missouri, Big Hole or Yellowstone rivers are flowing high or low. All told, there are 237 stream gauges on rivers across the state.

Some long-flowing rivers like the Yellowstone and Missouri have several gauges. For example, the Yellowstone’s flows can be measured near Gardiner, Livingston, Billings, Forsyth, Miles City, Glendive and Sidney.

An interesting observance in the spring is when ice jams clog a river. At some of the gauges you will see the water climb like a set of stairs almost straight up. When the dam breaks, the river level abruptly drops.

The USGS streamflow website is fairly easy to navigate. Once you log in to waterdata.usgs.gov/mt/nwis/current?type=flow you will find the list of the gauges. They are divided by basins: Upper Missouri River Basin, Lower Missouri River Basin, Yellowstone River Basin and Upper Columbia River Basin.

Next to each gauge site you can scan across and see the height of the water at the gauge, which is informative when it’s flood season. Rivers have a flood stage, so when the river hits that height it will flood.

Shown next on the home page is the current water flow, which is measured in cubic feet per second, or cfs. Next to that column is another that shows the long-term median flow for that same date, which is interesting for comparisons. The last line is the water temperature. Not all gauges have this feature.

If you click on the blue numbers to the left of the stream, you will be taken to a table that shows you what the flow has been on that stream for the past week. Below that is another table that provides more numbers for comparison, such as the median and mean for that date, as well as the maximum flow on that day.

Above this information is a separate box where you can search out streamflows for that gauge on different dates. If you wanted to see how high the Yellowstone River was flowing during June 6-13, 2011 – a year of record-setting flows – you would see the graph climb from around 50,000 cfs to 75,000 cfs in that one week. The normal flow for that time frame, the graph shows, ranges from around 42,000 cfs to 50,000 cfs.

All of this information can help boaters decide where to float. Low streamflows may mean smaller rivers like the Stillwater or Smith are hard to navigate in a raft but would be OK in a kayak or canoe. High, cold water can be a good reason to stay off a river until it’s not so scary, unless you are a whitewater rafter or kayaker. Then, high water is something you might seek out.

All of this talk about a streamflow website may sound nerdy, but it is a great source of information if you like to spend time on rivers.