Streams are part of the global water cycle. A healthy stream is shaded and meanders, providing food and habitat for plant and animal life and cools our feet in Summer.
When streams move too quickly, the stream bed is scoured, removing nutrients and habitat that its life depends upon. By moving slowly, water more readily recharges ground water that we continuously draw from.
There’s another facet to slow moving streams that has been gaining attention – the hyporheic ( hi-po-ree-ik) zone. That’s the area under a stream where ground water and stream water meet. It’s unique to either and serves to moderate water temperatures: making it cooler in Summer and warmer in Winter. Here the water is also oxygenated. Microbial activity breaks down pollution. All of this is extremely important for water quality. When water moves too quickly these benefits are mostly lost.
We normally don’t see this area but scientists and other water enthusiasts who study water are working to get the information out. Here’s a short video for an overview:
Slow the Water Down
Even though we can’t see underneath a stream, we can have a positive impact. Slow the water down.
- Where water runs, make it walk.
- Where water walks, make it crawl.
- Where water crawls, help it to enter the ground.
In this way, we can all play a part in recharging groundwater and keeping streams healthy.
One Rock/Log Dam
One way to slow water is to go outside when it rains and see where water is running. Maybe it crosses your driveway and washes it out in a heavy rain or perhaps it just flows down a hill and enters a wetland or other area. Using rocks or logs, create a single layer dam in its path. It doesn’t have to be tall but should span the width of the flow and a little bit wider. That’s enough to slow the water. If you have a lot of water running make several of these dams along the flow. This is a simple but effective way to help recharge groundwater.
Photo Credits
“New River (Mouth of Wilson, Virginia, USA)” by James St. John. Used under CC BY 2.0. Cropped from original.
“Rock Dam” by Lorraine Skala