What is CFS
This stands for Cubic Feet (per) Second. CFS equates to the volume of water moving downriver in a unit of measurement. The river’s width and depth, as well as elevation contours which aid the movement of the water are used to calculate an average volume. Since each river has unique measurements, they will have a personalized CFS.
What is gauge height
This is how deep the water is at a centralized metered location. The data reflects the point at the data collection area. This snapshot of data doesn’t reflect the entire river stretch – as there may be points along the way which may be deeper, or shallower.
Rivers are dynamic
As many of us have experienced, each river adventure is different – and have diverse features throughout its route. The flow of water throughout the year does change. There are many factors which lead to these changes: rainfall, drought, downed trees, dam releases, or flooding, just to name a few. Low water may lead to scraping the hull or walking your kayak. This will make the length of time on the water longer, and more paddling is needed to reach your destination. Higher water levels may result in faster current, flooding and energetic waters (rapids, riffles, etc.) and possible increase hazards (strainers, debris, downed trees). Launching and landing areas may be more difficult to navigate as your access points may be altered.
Are CFS all the same
Short answer is no. Let’s say one river has a value of 500 CFS. This is not universal understanding of all rivers. One river @500 CFS may equate to a gentile flow and hazard free environment. However, in another river this may represent a serious draught. An example: a country segment of the Milwaukee river may be currently running at 500 cfs, which is a pretty good paddle environment. However, if this value was for the Wisconsin River, this would feel like a trickle.
Why is knowing the CFS/gauge height important
As part of your paddle trip planning, there are many factors to consider. Understanding your route, distance, alternate take-outs and viewing the current CFS and gauge height paints a better picture of what to expect. One may research fellow paddler’s trip reports to recap an individual’s trip taken down river. Good trip reports will indicate CFS, gauge height, type of vessel, route (or path) taken, and the segment of the river. A trip report from someone who doesn’t enter this data only provides a snapshot image of their experience at that particular moment, and may not reflect what you will encounter.
Current data USGS and American whitewater are ideal for paddlers (links will open local Wisconsin rivers). Although, these two may not always provide any data for the river in which you wish to paddle.
USGS is a government run service, monitors some major river stretches in each state. The data collection area may be miles away from your access point. One should attempt to find your nearest data location. The site has the ability for the user to research past years’ worth of historical data. This is a great resource to see if that last rain storm helped out your river - or if it is in a dangerous flood stage.
AWW – works with USGS data provides a color scheme of red, yellow, green to depict if the river can be ‘ran’ (ease to paddle). This also shows level of difficulty for rapids. If the river reading is red, only experts with proper training, kayak, and rescue skills should attempt this section. This is mostly for the white water kayak paddlers - but the information can be utilized by any paddler.
Outfitters/guide companies are a great resource for paddlers! They know their local area and rivers, since they paddle them frequently. They will provide present data and knowledge about the river - if sections are good to paddle or if hazards are present. Let them paint the picture of the river trip for you, something the web sites can’t offer.
Putting this into perspective:
Take a look at this short video of the Milwaukee River. On this particular section of river a really good CFS is between 600 to 800, and anything above 6.3 is a decent height. This was taken just prior to a pretty good rain storm we had in the area, which lasted all night. Note the CFS and river height numbers in the lower right corner.
Right boat for the right water
Including both CFS and gauge height data into your trip, you can now plan if your kayak is suited for your adventure on the river. Knowing there may be something other than flat, and non-dynamic water (rapids, riffles, drops), one can make better choices when deciding if their kayak is suited for the water. Planning ahead provides the paddler with the knowledge to make smart choices, and if their paddle skills and craft are proper for the environment.