Last month I made a post about the gulf dead zone - an area in the Gulf of Mexico that contains very little sea life, due to input of nutrients from the Mississippi River. According to information I have read in the past, the main contributors of these nutrients are agricultural areas in the vast Mississippi River watershed. However, I also found an EPA study that indicates that sewage discharges (even treated ones) may be a larger factor. I'm not sure which is the leading cause, but it is safe to say that stormwater/sewage overflows as well as runoff from landscaping in Pittsburgh and other cities in this large watershed contribute at least a small bit to this.
Recently I found a New York Times blog entry indicating that the Gulf Dead Zone was particularly large and problematic this year.
In any event, 'slow water' practices that encourage water to soak into the ground or flow through streams and wetlands are one of the best ways to reduce the amount of these nutrients in runoff. Ironically the nutrients themselves are great for plants - it's only a problem when too much of these vital nutrients enter waterways where they don't belong. Projects like the possible 4-Mile Run Daylighting project in Pittsburgh help reduce this problem in two ways: by reducing the number of stormwater sewage discharges into the rivers, and by allowing wetland and creekside plants to filter nutrients out of the water. Constructed wetlands are also great when placed between treated sewage discharges and rivers, because sewage treatment plants can't remove all of the nutrients from the river.
This summer has been a hot one so far, but there are signs that its peak has passed. At least one maple tree thinks it is time to start turning red:
I think this maple tree may be a bit premature. However, in exactly 1 week, my time in Pittsburgh is ending for now and I will be driving back to Vermont where I will continue working on outreach for the Pittsburgh Park Conservancy while attending classes at UVM. I intend to keep this blog going, with posts relating to Vermont, to Pittsburgh, and to anywhere else where I learn neat things about runoff management and water flow. I want to thank everyone in Pittsburgh I have talked to for their input and support. If anyone has any thoughts on this blog, please do leave a post or email me. At some point, a similar blog may be created specifically for the 4-Mile Run watershed. This blog, however, will hopefully follow me wherever I go.