Sunday, November 23, 2014

Eutrophic Beauty

The Patapsco River forms Baltimore Harbor a few miles downstream from here. It has become a bit of a joke because of its poor water quality. From the surface this section looks remote and nearly untouched and it reminds me of some streams I know in the mountains of North Carolina even though this spot is just a short drive from the city. As soon as I submerge a different view appears. Everything is covered in thick olive algae. Dense algal growth is pretty normal this time of year in our rivers, but this amount is excessive. Even the sand bars are encased by a frosting of brown algae. It didn’t seem like I would see much more than river scape on this trip. Eutrophication is the over fertilization of waterways. Excess nutrients that come from septic systems, leaky sewers, lawn fertilizers, car exhaust and farms enter our rivers and streams and make excess algae grow. Usually it is unicellular phytoplankton that bloom and turn the water turbid or green. Occasionally, as is the case here, the excess fertilizer results in more macro filamentous algae that coats the river bed. I float in the eddy just to the side of the main flow where a riffle spills into the larger pool and watch the play of the air bubble curtain that forms when the water tumbles over a foot tall falls. Everything dances to the beat of the current. Air bubbles dive to the bottom and drift back to the surface. Water pins the algae flat to the rock, and vortices in the current make the algae dance up into the water then mash it back flat to the rock again. Tufts of bright green algae stand in sharp contrast to the olive drab background and pulse with the current. Even degraded waters are beautiful. I was just about to give up looking for life other than algae when I saw a sculpin nestled between two furry cobbles. Its dorsal fin looked like an oak leaf wedged between rocks and undulated in the current. It’s body looked like a rock. Amazing. Even on a day where my expectations to witness fish was low, I get to see one of my favorites. The sculpin was black, orange and red mottled and sat motionless on the bottom the way sculpin do except for its dorsal fin that waved in the current. The fish finally skittered off into a new crevasse when I stayed too close for too long. Impacted doesn’t mean ugly, or wasted or throw away. It just means impacted, and the life that continues to thrive is inspiration to reduce the impacts that affect our rivers. The Patapsco is a beauty, eutrophication and all.

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