Recent reports of the demise of Dancing Sands Spring are an exaggeration and premature.
Although the flow rates for the popular natural spring near the Lake Wingra shoreline have declined from a high of 55 gallons per minute (gpm) in 2007 to a low of 13 gallons per minute in 2009 (the most recent year for which spring flow data are available) the spring on the campus of the UW-Madison Arboretum was still flowing when visited this morning.
It is understandable that one would might not see the sand boils at first glance because of the water cress that sometimes clogs the spring channel–in fact, I had to push the invasive weed out-of-the-way to see to the bottom of the channel. The sand boils are so characteristic of the spring that their absence would indicate that the spring has stopped flowing. But that’s not the case, at least now.
Also, another reason for thinking that something has happened to the spring is that the channel has a different appearance this summer. This is because the beaver dam just downstream has raised the normal water level in the channel from its usual two to three-inch depth to a depth of more than one foot.
We will continue to check the spring this season because the possibility that continued building and excavation in the watershed will alter groundwater flow and either reduce or eliminate the groundwater discharge to Dancing Sands, or other nearby springs.