Where are the Springs in Spring Harbor?
One has to look closely now to see remnants of the large and bountiful springs that have, for many centuries, drawn humans to live by the shores of Lake Mendota in the Spring Harbor area. Many springs were once located along the shores here, including two very large springs in Merrill Springs Park and Spring Harbor Park. A couple of decades ago both parks had large, beautiful springs, with clear, cold, bubbling water. Fish were commonly seen in the streams fed by the springs.
There are many ideas on why the springs disappeared. Most commonly, the demise of the springs is blamed on urban sprawl and interception of ground-water recharge because of storm sewers. However, the loss of springs at Spring Harbor and Merrill Springs Parks corresponded with the installation of a water-supply well in Indian Hills by the city of Madison in 1960.
Historical data collected by the U.S. Geological survey in 1958 showed that the Spring Harbor Spring flowed at about 75 gallons per minute (GPM) and the Merrill Spring flowed at about 100 GPM. Water temperatures were about 51-54° F. This means that one could hold a gallon jug at an imaginary outlet in the spring and it would fill in less than a second! In 1967, one measurement at Merrils Spring was recorded to have a flow of 140 GPM; however, soon after the city well was installed neighbors started noticing daily luctuations in spring flow, probably corresponding to pumping at the public well. By 1970, Merrill Springs periodically dried up, and a spring survey from 1975-1977 at Merrill Springs resulted in 6 out of 8 measurements having no flow.
Results from a ground-water study by the U.S. Geological Survey in 1992 showed direct effects from pumping at the city well on ground-water levels below the old location of Merrill Spring. The pumping rate at the city well averaged about 2,300 GPM (2.5 million gallons per day) in 1992.
In the mid-1990s, the pump at the city well broke down and both springs started flowing again within a few days. Thus, it appears that our springs are not dead but only sleeping, waiting to surface again when less water is pumped from the city well.
A couple of decades ago we unknowingly lost one of the most prized natural resources on Lake Mendota, so prized that Native Americans had villages in our neighborhood for thousands of years, at the expense of having abundant clean running water come out of our tap. But, maybe the springs aren't gone for good, and maybe it is possible to realize the environmental value of the springs in comparison to the benefits gained from having a high-capacity well nearby. Maybe it is possible to have at least part of the natural beauty and environmental benefits associated with the springs restored.
Acknowledgements: Thanks to Jim Krohelski at the U.S. Geological Survey, Middleton , Wis. , for providing data for this article. Written by Faith Fitzpatrick; May 14, 2003.