Thursday, May 11, 2017

Watershed Stories

Today we had a new guest: Sage Passi, Watershed Education Specialist with Ramsey Washington Metro Watershed District.  We wondered, "what is a watershed?" We learned it is an area of land that drains into a body of water, just like our school is part of a watershed area that drains into Lake Phalen. It can include buildings, roads, and planted areas - what ever is on that land area. She led us in exploring maps that helped us understand how our watershed has changed over the years, with more impervious surfaces (where water does NOT flow through) in place of pervious surfaces (where water DOES flow through.) For example, we looked at an old map of the area around our school that showed fewer houses and streets and more farm fields and natural areas. Now there are more roofs, roads, and driveways. This means we have more run-off of stormwater when it rains, and that can carry more pollutants to our water bodies, like Lake Phalen.

What kind of pollutants? Trash was the first one we thought of, but other pollutants matter too. Like: oil or gravel that might wash off roads, pet waste (like dog poop), road salt, and even leaves and grass. Some of those things like dog poop, leaves, and grass might not matter if there was just a tiny amount, but when it rains, the stormwater can carry that stuff all to one place: like Lake Phalen where the nitrogen and phosphorus in those things can make algae grow, make lakes green, and make it unhealthy by reducing the oxygen that fish and other water life need to live. That's why every bit matters, because our land is all connected to our water...

Sage brought us outside to practice testing the quality of the water.  Here's some of the pictures below. Thanks Sage!

pH testing

Testing for Dissolved Oxygen

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