Monday, May 16, 2016

Storming and Norming lead to Underperforming

Just from my brief exposure so far, I have concluded that the management of stormwater runoff is typical of our engineered environment in that much effort is put into the design and construction of a device, after which ensues a lifetime of neglect. It's not due to lack of regulation or even oversight, but a lack of attention by owners and a failure of governance. A well constructed stormwater pond can degrade due to erosion, poor control of vegetation, or flowpath blockages and remain that way for years, all the while earning its full TMDL credit, though performing only half as well as it should. The local authorities are loath to penalize or even notify violators of their maintenance obligations out of fear of having a negative economic impact on business. State and federal enforcers are just as remiss.

Now that Environmental Site Design has downscaled the control of stormwater to smaller devices spread throughout a new development site, it will be interesting to see whether things will be better maintained due to aesthetics and scale. Education will be key. Fortunately, the Design Manual spells out the maintenance requirements for each device type.

Here's the type of problems that degrade a stormwater pond. The photo here is from a place I frequent that has not been maintained much for about 5 years. Trees grow on embankments where the roots compromise the dam's ability to hold water. Banks are eroded into the pond, reducing the vegetation inside, causing pooling of water, and reducing the overall pond capacity. Cut trees are left inside the pond, putting more nitrogen into the watershed as they decay. I hope to catalogue many stormwater devices such as this in Calvert County over the coming months and use this in presentations to those who need to know. They will be posted on my newest tab on this blogger site.

Featured Post

Git 'er Done

By Mark Rain T o get them all done in time to avert ecological armageddon, the thirteen prescriptions for healing the planet offered by...