Wetlands

Last night I went to a chapter meeting of the Master Naturalists to listen to a hydro-geologist speak about wetlands.  He explained that a hydro-geologist studies water in the aquifers while a hydrologist studies surface waters.  He was an interesting speaker and I learned quite a bit about water flows.  Sometimes lakes will contribute to the aquifer underneath.  Sometimes the aquifer contributes water to the lake. You can experience this when swimming or wading.  When you come into a cold spot that indicates water coming in from an aquifer.  Most lakes, he says, both give into an aquifer and receive water from an aquifer.  All of this depends on the geology beneath the lake.  Surface water can be days, weeks and months old.  Aquifers hold water that is decades to centuries in age. The lowest aquifers hold some very cold water than can be a millennium old.  Our speaker used the current situation in White Bear lake to illustrate his points.  White Bear gives water to an aquifer and receives water from the same aquifer.  Even though the area is not in a drought the water in the lake remains low because the cities of Centerville, White Bear, Lino Lakes and surrounding communities pump water out of the aquifer on one side of White Bear Lake.  Both St. Paul and Minneapolis do not pump water out of the aquifer for community use.  They use surface water straight out of the Mississippi.  This hydro-geologist says St. Paul has the best system.  With the chain of lakes on the east side of the city, St. Paul has a 28 day supply with wells available as a back up. Minneapolis has a 4 or 5 day supply.  Drinking surface water is a better choice because it is the more sustainable choice.  Pumping the aquifers dry will not last.  And watering lawns?  He thinks the practice should be outlawed.  I agree with him on that one.  I really enjoyed this engaging, thought provoking lecture.  I am already fairly careful about my water consumption.  But after hearing this talk tonight, I am motivated to conserve even more.  Water is a precious resource.  I don't want our water all used up on silly things.