The rains of recent weeks have set records. Their runoff has washed into the Yahara watershed, carrying consequences and surprises like so much flotsam and jetsam. I went looking for them last Sunday along the north shore of Lake Monona and up the middle stretches of the Yahara River.
Almost everywhere I looked on, around and under the water's swollen surface, I saw evidence of the catastrophic torrents.
The first sign was at Olbrich Park, where I launched my kayak onto Lake Monona. Whenever I've put in here before, I've scrambled down over the rocks that stabilize the shoreline, stood on the lakebed in knee-deep water, lifted my boat from the shore down onto the water and then settled into the cockpit. But the water was so high on Sunday that it covered the rocks and lapped at the lawn. I set my kayak on the water, stepped off the grass and into the boat.
A handful of dead fish were floating on the surface nearby, perhaps the result of stress from the surge in nutrients and pollutants carried into the watershed by the recent runoff. There was also the usual detritus: the occasional plastic bottle with its cap screwed on tight, pieces of Styrofoam here and there, an empty potato-chips bag, a gull's feather.
But then, a slab of planking from someone's dock, floating just below the surface. Not something you see every day on the lake.
Along Lake Monona's north shore, higher water overwhelmed the lake weeds that often grow to the surface, and submerged more of the overhanging tree limbs at the foot of the Lakeland Avenue bluff. At least there was more coarse, woody habitat for fish.
Farther west, Yahara Place Park was on the verge of submergence. Here, the central Yahara River was bringing far more water than usual into Lake Monona. Its discharge in the previous week had twice exceeded 400 cubic feet per second, according to U.S. Geological Survey records, and for most of the last seven days it had ranged between 200 and 300 - as compared to the last three Augusts, when the median discharge varied between 40 and 100.
The difference was visible in the increased violence with which the Yahara's current was disturbing Lake Monona's surface. It wasn't the Mississippi emptying into the Gulf, but the dynamics here at the Yahara's outflow were more dramatic than usual.
Venturing up the Yahara, I found a river that was flowing high and wide. The bridges that span it appeared lower. There was still plenty of clearance for me to pass under them in a kayak, but the difference was noticeable. The U.S.G.S. gauge at the East Main Street bridge confirmed this: The water depth here was approaching eight feet.
The three-year median depth for this gauge hovers around three feet throughout the month of August. Under those circumstances (assuming I had the balance), I might be able to stand up in my kayak while floating under the Yahara bridges. If I tried that now, I'd bang my head on most of them.
I'd heard a rumor that the pedestrian-bicycle underpass at the East Washington Avenue bridge was flooded and might be navigable. This proved unfounded, but not by much. Yet further upstream, the river had crested the Yahara's east bank at Tenney Park - again, not by much, but enough that I could paddle my kayak over the rocks that stabilize the riverbank. I was now floating an inch or two above grass. This was disorienting to the verge of inducing dizziness.
From a vantage point below the Tenney lock and dam, I watched Lake Mendota spill its waters down the Yahara. Record rains result in roaring releases here: Lake Mendota catches runoff from about 200 square miles of surrounding landscape, and had swollen to a level about 20 inches above its 27-year median for August. Discharging the water downstream was, in part, an effort to spare the big pond's low-lying lakeshore property owners from flooding.
Downstream at Lake Monona, yet another U.S.G.S. gauge was reading two feet above its August median. Maneuvering my kayak west along the north shore toward Monona Terrace, I passed docks that had been submerged or had their decks removed - in some cases by property owners who had stacked the decking onshore, in other cases by waves - leaving skeletal pier frames.
From a kayak not far off its north shoreline, Lake Monona appeared to bulge toward the south horizon like a pregnant tide in some vast inland sea. As memorable views go, it was a panorama as ominous as it was spectacular. But somewhere over that far horizon, residents of Belle Isle had been sandbagging their properties against the high water that was encroaching on their lawns. From their perspective, the view toward the north must have appeared menacing indeed.
Deluges by the numbers
According to data compiled by Scott Lindstrom of the UW-Madison's Space Science and Engineering Center, 11.38 inches of rain fell between Aug. 9 and 22, exceeding the previous 14-day mark of 10.23 inches recorded between Sept. 6 and 19, 1938. The seven-day record, set in September 1915, was also broken, and we flirted with the 30-day record of 15.36 inches that rained on Madison between May 17 and June 15, 2000.