Sunday, November 25, 2012

We adopted a stream–and it’s pretty sick….

The saga continues!  Last winter, our family attended a stream monitoring session in Accotink creek.  After that experience, we decided that we too wanted to volunteer and adopt our own stream.  I took the stream monitoring training sponsored by the Northern Virginia Soil and Water Conservation District, and we were assigned a stream in Eudora Park in Fairfax County, VA.  Our first stream count was a little disappointing – we only found 21 invertebrates.  But hope springs eternal, and we looked forward to the Fall count!


The Fall count happened today, and it was a real bummer.  Our stream is not looking good.  All we found were 4 fly larvae and one oligochaete worm.  In a healthy stream, we should have found at least 200 invertebrates over 3 or 4 samples.  We were a little confused, because our stream sits in the center of a beautiful wooded park that’s used by many people for recreation.  So what’s going wrong with our stream?  We can’t say for sure, but here are a few problems that are common in developed areas such as ours:

1)  Erosion – Often, in developed areas, we try to channel water to specific waterways, rather than allowing the water to flow through smaller streams, floodplains, wetlands, or other soil on its way to the larger tributaries.  We bury smaller streams to allow development and move the path of the stormwater.  Additionally, hard surfaces (roofs, roads, sidewalks)  keep the ground from absorbing water.  By shunting stormwater to just a few streams, we really increase the speed and power of water as it moves through these streams.  If you see a stream bank that looks like this,   you’ve got a seriously eroded stream.

2)  Pollution and sedimentation – Pollution in streams comes from several sources:

  • sedimentation from the erosion (see the picture, above)
  • phosphorous and nitrogen from overuse of lawn fertilizers
  • oils and other toxins that run directly off roads, roofs, and driveways and into waterways (no slowing down and cleaning through wetlands or other soils)
  • large trash carelessly discarded or stuffed down storm drains (see the plastic bags stuck in the tree roots in the photo above)

Our walk back home after our stream monitoring session was a quiet one.  Needless to say, we were disappointed and sad to see the condition of our stream.  This is a great illustration of why we greenmomsters need to get involved, change the status quo, and protect our children’s environment.  Is there hope?  Yes!  Our local Soil and Water Conservation District is working hard to restore and stabilize eroded stream banks.  Additionally, folks are organizing to save the streams that are still healthy.  Northern VA was host to such an effort recently when a group of concerned citizens saved “Tyson’s Last Forest” from a popular highway project.  It can be done!

We’ll keep you posted regarding our stream (we may be assigned a new stream).   See you in the spring!

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