Thursday, 26 March 2009

Harnessing the Power of Nature





Green barrel, originally uploaded by VanWhelan.

One of the benefits to my (N.'s) job is getting to listen to discussions on current research in water management. The scope of that general topic is endlessly wide, and, while I don't find it all fascinating, every once in awhile something really strikes home with me. This week it was a discussion given by a civil engineer about the affects of the use of rain barrels in storm water management. 

This gentleman is part of a program that gave out specially designed rain barrels for free to residents within a certain watershed in order to determine if this was an effective way to prevent excess rainwater from entering the storm water system. Residents participated on a voluntary basis and the rain barrels were installed for them to ensure it was done correctly. The original idea was that the barrels would capture the fast flowing rain water, and then through a slow leak valve at the bottom it would empty into the ground.

What they determined was rather surprising: they actually had a problem with gardeners! You see, the barrels were designed to fill during rain events and then slowly leak out of a specially designed valve over the course of a couple days. This way the water didn't rush into a stream they were trying to restore and cause damage to the fragile ecosystem. It would also allow the water to be naturally infiltrated into the groundwater supply. So what's their beef with gardeners? Instead of releasing the water, gardeners would keep the water stored in the rain barrel for use in irrigation. Because of this, barrels were much more likely to overflow defeating their original purpose (in the eyes of the civil engineers at least). 

Honestly, I never thought about rain barrels as a way to manage storm water overflow. I looked at them as a way to capture a naturally occurring resource and use it at a later date. This doesn't mean that rain barrels can't serve both purposes. One gentleman said he and his wife were constantly battling over the rain barrel; his-wife the gardener-won.  As a compromise they purchased another. They are still capturing all of the rain which prevents pollutants from getting into our surface water and excessive erosion in our stream beds, but now they are reusing some for the garden and slowly infiltrating the rest to replenish ground water supplies.

Life is always about adaption and compromise.  Do you use a rain barrel? Rain garden? If so, how effective do you think they are?