State Parks & Forests

Safety

The Dangers of Paddling High Water

Most people know better than to go paddling in flood conditions. But paddling is a lot of fun and it’s tempting to see what it’s like with some extra water. Because there is so much variation in rivers and what happens during high water, it’s worth taking some time to consider the potential dangers.

The best advice to anyone is don't go out into floodwaters . There are more dangers than most people can imagine. First of all, a river that usually moves at a slow to moderate pace can become a raging torrent with pushy and unpredictable currents, big waves, and/or large debris. With few exceptions, a small boat is helpless in such conditions and its occupants, even wearing life jackets, are literally risking their lives.

In normal, moderate conditions, any moving water can capsize a canoe or kayak that accidentally leans upstream, something that happens easily and often without warning. The faster and more turbulent the water, the more quickly this can happen. In addition, most recreational streams contain obstacles and in flood conditions many more are washed in. These are generally difficult to deal with when the water is running high and fast.

At high water, normally placid streams take on many of the traits of whitewater rivers. See the American Whitewater Association’s Safety Code [exit DNR] about river hazards.

The examples discussed below reflect conditions created by heavy rains in the summer of 2007 and late spring of 2008. The resulting flows were abnormally high for those times of year, but they are not at all unusual during and after spring snowmelt. High flows during spring may be more dangerous than in summer because of :

  • More debris in the river,
  • More undercutting of riverbanks
  • much colder water. Cold water presents a significant risk of hypothermia and immediate incapacitation due to sudden immersion in water below 50 degrees.

Paddling in high water would be exciting—until you were slammed against a bluff, got stuck under an undercut rock, or became trapped under a downed tree across the river (called a strainer [exit DNR]). Strainers are the greatest hazard on Wisconsin’s smaller rivers; far too few paddlers either recognize their danger or have the skills to maneuver away from them. Strainers allow water to pass, but their submerged branches hold onto things like boats and people. Death by drowning comes quickly.

Extreme Example: Kickapoo River

The Kickapoo River in southwestern Wisconsin is well-known as a beginner’s river - safe, shallow, and relatively slow with normal summer flows of around 100-200 cubic feet per second (cfs), measured at the LaFarge dam. On August 19, 2007, the flow shot up to 15 to 30 times this level, about 3,000 cfs, raising the river 10 feet above its normal level. On June 8, 2008, the flow hit an unbelievable 20,000 cfs - 12 feet above normal and 4 feet above flood stage.

Unlike some other rivers, the Kickapoo rises quickly when it rains, and it also drops quickly. In the days after August 19 the flow dropped to around 600 cfs, thanks to several days without rain. Similarly, less than a week after the record flow of June 8, 2008, the river had dropped to 1,000 cfs and four feet above normal.

But flow rates cannot safely be forecast. On August 24 and 25, 2007, the Kickapoo rose again to over 1,600 cfs, which is unsafe for anyone - further evidence of the unpredictability of this popular paddling site. So paddlers need to be aware that river levels can change dramatically even in the absence of heavy rains. The Kickapoo is a bit unusual in how quickly it rises and falls, but it is typical in being unpredictable in the days after storms.

Other Wisconsin Rivers

Other waterways present the same risks, with the differences primarily being the level of scale.

  • The Wisconsin River may look benign at high water levels, but don’t be fooled. It runs fast with unpredictable currents that can easily spin a boat and cause it to wobble, with the risk of tipping upstream and being rolled over by the rushing water.
  • Smaller streams like the Mecan River generally have more obstacles, which become far more challenging than normal and very dangerous in high water. Overhanging branches, common on this and other small streams, often block the main channel. In high water when the current is running fast, it can be very difficult to find a safe route past these obstacles, which work like nets to catch and capsize boats.
  • The Sugar River flows through mostly bottomlands with an average summer flow of 250 cfs at Brodhead. On August 23, 2007, it peaked at more than 5,000 cfs, 9 feet above normal. Before the June 8, 2008 storm, it was already fairly high, running at 600 cfs; the rains boosted its flow to nearly 4,000 cfs. It rose 6 feet above its level a few days earlier, to 3 feet above flood stage.

    Because it flows through such a broad floodplain, the Sugar tends to spread out more than it speeds up. However, it still carries a lot of debris that accumulates in bends, where paddlers also get stuck. No matter where they are, downed trees and logs (strainers) are deadly hazards. The Sugar also constricts where there is a defined riverbank, and when it’s carrying 20 times as much water as usual, those places become extremely dangerous due to the faster current, tight turns, and greater likelihood of debris there.
  • The Yahara River is similar, with an average flow of around 285 cfs at Fulton. On August 20, 2007, it peaked at about 2,800 cfs, more than 5 feet above normal. On June 9, 2008 it hit 2,500 cfs, dropped to 1,200 cfs and then rose again to nearly 3,000 cfs. Like many Wisconsin rivers, the Yahara is generally fairly wide but constricts abruptly in places, resulting in sudden surges, collections of floating debris and turbulent currents.

After the Flood

Complacency kills. When flood waters recede, it’s tempting to think that the danger is past. Floodwaters pick up all kinds of debris; they also uproot trees by knocking them down and undercutting their roots. All this stuff gets deposited when the river goes down, and it creates impassable obstacles. The most dangerous are the many strainers that appear after a flood. On July 28, 2007, a group of young paddlers got stuck in a tree that had fallen over the Red River west of Shawano. They were lucky that the river was low and moving slowly, because most of them had no idea how to cope with the obstacle. In a faster current the situation could have been disastrous.

Beginning paddlers, such as those on the Red, can be victims of ignorance. Experienced paddlers, on the other hand, are at greatest risk of death from complacency. They can overestimate their skills at the same time as they underestimate the hazards of a river that has recently flooded. For example, although the Kickapoo empties quickly, at 1,000 cfs it’s still pushy and a lot of the debris - including entire trees - has grounded and can present significant obstacles. The same is true for all other rivers, no matter how large or small. Generally, the larger the river is, the more likely it is to have open channels - and conversely, the smaller the river the more likely it is to be choked with debris.

Suggestions for Safe Paddling

Anyone considering venturing out onto a river should become familiar with how it behaves at different water levels. There are many anecdotal guides to Wisconsin rivers, and most of them leave much to the imagination. The U.S. Geological Survey [exit DNR] provides flow and water level data for many paddleable streams.

Talk to other paddlers. There are several paddling clubs in and near Wisconsin, and most of them have Web sites and discussion groups:

Most of all, if you have any doubt about a river or your ability to have a safe trip, wait until conditions improve. Go biking, hiking, kite-flying—just give the river time to settle down. It will.

David E. Birren

Last Revised: Friday June 20 2008