CitiesGoGreen - February 2009 - (Page 28) Our planning must accomodate the realities of the natural processes we rely upon. Green Infrastructure I want to deliberately distinguish Green Infrastructure from “greenspace,” which is a generic term describing land which is open, pervious and mostly undeveloped in terms of conventional or gray infrastructure. I believe Green Infrastructure is a better term than greenspace for planning purposes. I define Green Infrastructure as a strategically planned and managed network of wilderness, parks, greenways, conservation easements, and working lands with conservation value that: • Supports native species • Maintains natural ecological processes • Sustains air and water resources • Contributes to the health and quality of life for communities and people This definition makes clear that Green Infrastructure is superior to simple greenspace in that, to be considered Green Infrastructure the land has to be the subject of an affirmative action of the community such as strategic planning, regulation, land acquisition and stewardship. Together greenspace and Green Infrastructure provide significant support to the vitality and character of the human and wild communities. Aquifer recharge, wildlife habitat, recreation, flood protection and food security are a few of the ecosystem services provided by greenspace and that serve to sustain our way of life. It is reasonable to imagine that the quality of our way of life is predicated on the quantity, quality and location of these ecosystem services. It is also reasonable to assume that as development pressures convert greenspace, the overall capacity to provide these services decreases. It 28 is sobering then, to realize that we may never have any more nor any higher quality ecosystem services than that we have right now. Perhaps therefore our quality of life is at its zenith. How’s the water? To explore the value and vulnerability of ecosystem services, let’s look at drinking water. Alachua County’s, and most of Florida’s, drinking water is mined from subterranean aquifers. It’s as if a sponge underlies Florida’s cities, farms, homes and industry. Rain allowed to drain into the ground is stored in these aquifers until pumped out for drinking, agricultural and industrial uses. The metropolitan Gainesville area is served by Gainesville Regional Utility (GRU), which provides 26 million gallons of drinking water daily to its 65,000 households (400 gallons per day per household; 10 billion gallons annually). To protect the source, GRU and regional water managers purchased conservation easements on about 7,000 acres of timber property. But is it enough? Alachua County has an average groundwater recharge of 12 inches annually, so the protected drinking water Green Infrastructure contributes 7,000 acre-feet or 2.3 billion gallons of drinking water recharge annually. Based on our average consumption, those 7,000 acres meets only 23% of the need. A few things should be obvious from this story. First, we have a 19 million gallon per day deficit in the drinking water Green Infrastructure in Alachua County. Second, the surrounding, privately-owned and unprotected greenspace supplements the existing drinking water Green Infrastructure. Third, that greenspace is keeping the cost of our drinking water affordable. We know that rain runoff from open space tends to be less polluted than that from the built environment and therefore it is cheaper to treat and therefore less expensive for the customer. Obtaining, cleaning and delivering drinking water is energy intensive. As energy costs increase, the As energy costs increase, the value of having the land passively do our work for us becomes even more economically important. value of having the land passively do our work for us becomes even more economically important. But new developments encroach on the wellfield, threatening its support system. Last year the City of Gainesville approved an 1,800-acre development proposal next to the wellfield and will include 1,900 new residential units. By approving this development the City risks losing greenspace which supplements the Green Infrastructure and helps replenish the aquifer. It is clear that if we do not protect and enhance our capacity to provide clean water as we add consumers, the cost of treating and providing that water will increase. Still people come and still we have to provide them with housing and places to work and play. Our ecosphere is running out of clean water to support the additional shrimp. What is Green Infrastructure? A strategically planned and managed network of wilderness, parks, greenways, conservation easements, and working lands with conservation value that: • Supports native species • Maintains natural ecological processes • Sustains air and water resources • Contributes to the health and quality of life for communities and people February/March 2009 http://www.CitiesGoGreen.com
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