05/29/2015
To our Tenants, Friends, Neighbors, and Customers of Arbor Trails:
Why are you watering after a storm?
Predictably, we receive many inquiries after a storm event as to why the irrigation system is running when the ground is wet? No, we are not crazy nor are we oblivious to the drought conditions in and around Austin. Rather, this has to do with how the project treats storm water runoff. The wet pond you see at the center of our project, in addition to looking nice, also serves as the repository for the storm water runoff for the development - as well as for part of MoPac expressway. Following a rain event, the pond level rises. The amount the pond level "rises" is the "new" storm water that has been introduced to the pond by the various storm water inlets in and around the Shops at Arbor Trails. If there is more water received than the wet pond can handle, that water overflows into the other "dry" basin adjacent and contiguous to the wet pond where it is held pending the cessation of rainfall. By our permits and by law, the pond is required to hold this storm water for at least 12 hours following the end of the rain event. On the other hand, the storm water received must be released (drawn down) within 72 hours after the rain event - assuming, of course, no more rain is received during that time.
So now that the rain has stopped and the pond(s) full, where does the water go? How is it drawn down? What does this have to do with you watering the lawn after the rain?
This is where the irrigation system comes into play. Our particular form of storm water treatment is called a retention-irrigation system. This means we are required to "capture" a specific amount of storm water runoff (retain it on site - hence the "retention" aspect) after which we are to discharge. The way it is discharged is through an irrigation system that pumps the storm water onto our land. The "filtering" of the storm water occurs in the suspension of solids in the pond, via the filtration of solids in the soil after irrigating and by the uptake of various nutrients by vegetation located on our site. In typical dry and hot Austin weather, this is a welcome event to help with the irrigation of the center. When there are successive rain events, it appears as though we are unnecessarily wasting water. Rest assured we are not, nor are we using potable water. Rather, we are complying with our permits issued by the Texas Commission on Environmental Quality (TCEQ) and the City of Austin. For further information, please feel free to contact management. Thank you for your interest and your patronage to the Shops at Arbor Trails!
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