Water is a major concern for the city of Philadelphia, and how we conserve and protect our water supply will only increase in importance in the future. Philadelphia maintains a Combined Sewer Overflow (CSO) system throughout the city to deal with all the household sewers and street drains. A CSO system works very well during normal days, but in periods of heavy rain the system can be overloaded and discharge raw sewage into our rivers.
It’s critically important that we reduce the amount of water entering our sewer systems as much as possible. In fact, all new buildings constructed in Philadelphia are now required to produce a rainwater management plan that addresses runoff and water conservation. At Greensgrow this issue is even more apparent because our entire farm sits on a slab of concrete, with very little natural drainage. We put a lot of thought into how to reduce and recycle our water and runoff.
When we grew lettuce hydroponically, we employed a closed-loop water system with very little wasted water compared to traditional farming. Because the water is continuously cycled, none is lost to drainage. Today at Greensgrow you will notice green roofs around the farm, drip irrigation in the high tunnels, trees and plantings around the property all which conserve water. Green roofs use plants to trap much of the rainfall that occurs during a storm, significantly reducing run-off around the property. In addition to the many border plantings that absorb rainwater, these roofs are contributing to the growing proportion of green space at Greensgrow that can absorb rainwater. For structures like our greenhouse that cannot support a green roof, we are experimenting with rainbarrels to capture some of the rain that falls on the greenhouse. Rainbarrels are very simple devices that store extra water until it is needed on those dry hot summer days that make Philadelphians hide indoors.
As more and more news stories document the growing water shortages in various parts of the country, pay attention to how you use water at home and come check out some simple solutions that we have on display at the farm. Water is a precious resource and it will take all of us to protect it for future generations.