Is Dougherty Lake a "lake" ?

 

Dougherty "Lake" is a Retention Pond

Alright, but what's the difference between a Detention pond and a Retention pond?  

A detention pond is a reservoir created to temporarily hold storm water runoff.  Detention ponds have no outlets or spillways and rely on natural processes such as evaporation for water removal.

A retention pond is a permanent pool of water in its design, constructed for the purpose of reducing downstream flooding. Retention ponds are designed with features like an outlet or spillway that regulates how much water can leave the pond at one time.

 

The Nature of Dougherty "Lake"

Dougherty Lake is a Retention Pond.  It will never be a pristine mountain lake.  It is the natural low point for about 250 acres north of Beaver Dam Rd including our subdivision.  As a result it receives every bit of storm water through MSD sewers in that area.  This includes all the fertilizer runoff from lawns and all debris (plastic bags and cups, and "you name it").   Of course all sorts of seeds and branches flow into the lake.  It can also be the final resting place for some of the wildlife you see.

On the bottom of the lake you will find probably a foot or more of pure muck & mud.  There are electrical lines and the pneumatic tubes which feed the bubblers.  

You do not want to go into the lake.

The debris also contributes to the lost fishing line in the lake.
"If you go too deep your line the lake will keep"

Any non-trivial amount of rain can change the characteristics of the lake.  During a deluge, a great deal of the water gets replaced.  The water coming through just the one 50 inch culvert can shoot out like a fire hose.

The lake is chemically treated, but as safely as we can with the most conservative techniques.  It takes a lot of effort to keep the retention pond from being an awful mess.  One deluge can cause big issues.  Without treatment the lake would look and smell like a sewage treatment plant within months.


Everyone should care about keeping trash out of the sewers

Trash (plastic bags, plastic bottles, stuff that blows off Waste Management trucks...) doesn't just look bad.  It causes havoc with the lake.  It kills wildlife.  It can clog the sewers.  It clogs the overflow grate (which costs everyone money to clean).

Same goes for grass clippings, branches, and those ankle breaking sweet gum balls.  They cause havoc too.  They end up decaying in the lake (adding to the muck) and feeding algae. 


Why we should all care - what can happen

Many people might not have been here in December of 2015.  

We had an "unexpected event" that caused rapid flooding.
A period of rain brought a significant number of large pieces of debris that covered the overflow grate. 





Even if you live east of the lake, this could have been very bad for the subdivision.



Disclaimer

https://www.youtube.com/watch?v=YMDrTMnm1IE
 


 

  

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